/* ============================================
   MYCLASS LK — GLASSMORPHISM DESIGN SYSTEM
   ============================================ */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

/* ============================================
   LIGHT MODE (Default) — Frosted Glass
   ============================================ */
:root {
    --primary: #4f46e5;
    --primary-light: #818cf8;
    --primary-dark: #3730a3;
    --primary-glow: rgba(99, 102, 241, 0.18);
    --success: #34d399;
    --success-light: rgba(52, 211, 153, 0.15);
    --warning: #fbbf24;
    --warning-light: rgba(251, 191, 36, 0.15);
    --danger: #f87171;
    --danger-light: rgba(248, 113, 113, 0.15);
    --bg: linear-gradient(135deg, #e0e7ff, #f0f4ff, #ede9fe);
    --bg-solid: #e8ecff;
    --surface: rgba(255, 255, 255, 0.55);
    --surface-hover: rgba(255, 255, 255, 0.7);
    --border: rgba(255, 255, 255, 0.7);
    --border-subtle: rgba(99, 102, 241, 0.12);
    --text: #1e1b4b;
    --text-secondary: #3730a3;
    --text-muted: #6366f1;
    --secondary: rgba(255, 255, 255, 0.4);
    --shadow-sm: 0 1px 3px rgba(99, 102, 241, 0.06);
    --shadow: 0 4px 16px rgba(99, 102, 241, 0.1);
    --shadow-lg: 0 8px 32px rgba(99, 102, 241, 0.12);
    --glass-blur: blur(20px);
    --glass-bg: rgba(255, 255, 255, 0.55);
    --glass-border: rgba(255, 255, 255, 0.7);
    --glass-shadow: 0 8px 32px rgba(99, 102, 241, 0.12);
    --input-bg: rgba(255, 255, 255, 0.7);
    --input-border: rgba(99, 102, 241, 0.25);
    --input-focus: rgba(99, 102, 241, 0.5);
    --input-focus-glow: 0 0 0 3px rgba(99, 102, 241, 0.15);
    --table-header-bg: rgba(255, 255, 255, 0.4);
    --table-header-text: #4b5563;
    --table-row-border: rgba(99, 102, 241, 0.08);
    --table-row-hover: rgba(255, 255, 255, 0.5);
    --nav-inactive: #4b5563;
    --nav-active-bg: rgba(99, 102, 241, 0.15);
    --nav-active-text: #4f46e5;
    --nav-hover-bg: rgba(99, 102, 241, 0.08);
    --btn-primary-bg: rgba(99, 102, 241, 0.85);
    --btn-primary-hover: rgba(79, 70, 229, 0.95);
    --btn-primary-border: rgba(99, 102, 241, 0.6);
    --modal-bg: rgba(255, 255, 255, 0.75);
    --modal-overlay: rgba(99, 102, 241, 0.15);
    --orb1: rgba(99, 102, 241, 0.2);
    --orb2: rgba(139, 92, 246, 0.15);
    --orb3: rgba(59, 130, 246, 0.12);
    --sidebar-bg: rgba(255, 255, 255, 0.45);
    --sidebar-border: rgba(255, 255, 255, 0.6);
    --header-bg: rgba(255, 255, 255, 0.5);
    --chat-mine-bg: rgba(99, 102, 241, 0.25);
    --chat-other-bg: rgba(255, 255, 255, 0.5);
    --radius: 16px;
    --radius-sm: 10px;
    --sidebar-width: 260px;
    --sidebar-collapsed: 68px;
    --transition: 0.25s cubic-bezier(.4,0,.2,1);
}

/* ============================================
   DARK MODE — Deep Glass
   ============================================ */
body.dark-mode {
    --primary: #818cf8;
    --primary-light: #a78bfa;
    --primary-dark: #6366f1;
    --primary-glow: rgba(129, 140, 248, 0.2);
    --success-light: rgba(52, 211, 153, 0.15);
    --warning-light: rgba(251, 191, 36, 0.12);
    --danger-light: rgba(248, 113, 113, 0.15);
    --bg: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
    --bg-solid: #0f0c29;
    --surface: rgba(255, 255, 255, 0.08);
    --surface-hover: rgba(255, 255, 255, 0.12);
    --border: rgba(255, 255, 255, 0.12);
    --border-subtle: rgba(255, 255, 255, 0.06);
    --text: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.85);
    --text-muted: rgba(255, 255, 255, 0.55);
    --secondary: rgba(255, 255, 255, 0.06);
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2);
    --shadow: 0 4px 16px rgba(0, 0, 0, 0.25);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
    --glass-blur: blur(20px);
    --glass-bg: rgba(255, 255, 255, 0.08);
    --glass-border: rgba(255, 255, 255, 0.15);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --input-bg: rgba(255, 255, 255, 0.08);
    --input-border: rgba(255, 255, 255, 0.15);
    --input-focus: rgba(129, 140, 248, 0.6);
    --input-focus-glow: 0 0 0 3px rgba(129, 140, 248, 0.2);
    --table-header-bg: rgba(255, 255, 255, 0.05);
    --table-header-text: rgba(255, 255, 255, 0.5);
    --table-row-border: rgba(255, 255, 255, 0.06);
    --table-row-hover: rgba(255, 255, 255, 0.05);
    --nav-inactive: rgba(255, 255, 255, 0.6);
    --nav-active-bg: rgba(255, 255, 255, 0.15);
    --nav-active-text: #ffffff;
    --nav-hover-bg: rgba(255, 255, 255, 0.08);
    --btn-primary-bg: rgba(129, 140, 248, 0.3);
    --btn-primary-hover: rgba(129, 140, 248, 0.5);
    --btn-primary-border: rgba(129, 140, 248, 0.6);
    --modal-bg: rgba(15, 12, 41, 0.7);
    --modal-overlay: rgba(0, 0, 0, 0.6);
    --orb1: rgba(79, 70, 229, 0.4);
    --orb2: rgba(139, 92, 246, 0.3);
    --orb3: rgba(59, 130, 246, 0.25);
    --sidebar-bg: rgba(255, 255, 255, 0.06);
    --sidebar-border: rgba(255, 255, 255, 0.1);
    --header-bg: rgba(255, 255, 255, 0.06);
    --chat-mine-bg: rgba(129, 140, 248, 0.3);
    --chat-other-bg: rgba(255, 255, 255, 0.08);
}

/* ============================================
   BASE & RESET
   ============================================ */
* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg);
    background-attachment: fixed;
    color: var(--text);
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }
button { cursor: pointer; border: none; font-family: inherit; }
input, select, textarea { font-family: inherit; }

/* ============================================
   ANIMATED GRADIENT ORBS
   ============================================ */
body::before,
body::after {
    content: '';
    position: fixed;
    border-radius: 50%;
    z-index: 0;
    pointer-events: none;
}
body::before {
    width: 500px; height: 500px;
    background: var(--orb1);
    top: -100px; left: -100px;
    filter: blur(100px);
    animation: floatOrb1 10s ease-in-out infinite alternate;
}
body::after {
    width: 450px; height: 450px;
    background: var(--orb2);
    bottom: -80px; right: -80px;
    filter: blur(100px);
    animation: floatOrb2 12s ease-in-out infinite alternate;
}

.app-wrapper::before {
    content: '';
    position: fixed;
    width: 400px; height: 400px;
    background: var(--orb3);
    top: 40%; right: 5%;
    border-radius: 50%;
    filter: blur(100px);
    z-index: 0;
    pointer-events: none;
    animation: floatOrb3 9s ease-in-out infinite alternate;
}

@keyframes floatOrb1 {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(60px, 80px) scale(1.1); }
}
@keyframes floatOrb2 {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(-70px, -60px) scale(1.15); }
}
@keyframes floatOrb3 {
    0% { transform: translate(0, 0) scale(1); }
    100% { transform: translate(-40px, 50px) scale(1.08); }
}

/* ============================================
   AUTH OVERLAY — Glass Login
   ============================================ */
.auth-overlay {
    position: fixed; inset: 0; z-index: 10000;
    background: var(--bg);
    display: flex;
    opacity: 0; pointer-events: none;
    transition: opacity 0.5s cubic-bezier(.4,0,.2,1);
    overflow: hidden;
}
.auth-overlay.active { opacity: 1; pointer-events: all; }

.login-left {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 1;
    padding: 60px 80px;
}
.login-form-wrap {
    width: 100%;
    max-width: 420px;
    animation: formSlideIn 0.9s cubic-bezier(.16,1,.3,1) forwards;
    opacity: 0;
}
@keyframes formSlideIn {
    from { transform: translateX(-40px); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

.login-welcome-title {
    font-family: 'Poppins', 'Inter', sans-serif;
    font-weight: 800;
    font-size: clamp(42px, 6vw, 64px);
    color: var(--text);
    margin-bottom: 36px;
    line-height: 1;
    letter-spacing: -1px;
}

.login-input-group {
    position: relative;
    margin-bottom: 16px;
    opacity: 0;
    animation: inputFadeUp 0.7s cubic-bezier(.16,1,.3,1) forwards;
}
.anim-stagger-1 { animation-delay: 0.3s; }
.anim-stagger-2 { animation-delay: 0.45s; }
.anim-stagger-3 { animation-delay: 0.6s; }

@keyframes inputFadeUp {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.login-input-icon {
    position: absolute; left: 20px; top: 50%; transform: translateY(-50%);
    color: var(--text-muted);
    display: flex; align-items: center; justify-content: center;
    transition: color 0.3s; z-index: 2;
}
.login-input-group:focus-within .login-input-icon { color: var(--primary); }

.login-input {
    width: 100%;
    padding: 18px 20px 18px 54px;
    font-family: 'Inter', sans-serif;
    font-size: 16px; font-weight: 400;
    color: var(--text);
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1.5px solid var(--glass-border);
    border-radius: 50px;
    outline: none;
    transition: all 0.35s cubic-bezier(.4,0,.2,1);
}
.login-input::placeholder { color: var(--text-muted); font-weight: 400; }
.login-input:focus {
    background: var(--surface-hover);
    border-color: var(--primary);
    box-shadow: var(--input-focus-glow);
}

.login-eye-btn {
    position: absolute; right: 18px; top: 50%; transform: translateY(-50%);
    background: none; border: none;
    color: var(--text-muted); cursor: pointer;
    padding: 4px; display: flex; align-items: center; justify-content: center;
    transition: color 0.3s; z-index: 2;
}
.login-eye-btn:hover { color: var(--primary); }

.login-btn {
    width: 100%; max-width: 280px;
    padding: 18px 28px; margin-top: 20px;
    font-family: 'Inter', sans-serif;
    font-size: 18px; font-weight: 700;
    color: #ffffff;
    background: var(--btn-primary-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border: 1.5px solid var(--btn-primary-border);
    border-radius: 50px; cursor: pointer;
    display: flex; align-items: center; justify-content: center; gap: 10px;
    position: relative; overflow: hidden;
    transition: all 0.35s cubic-bezier(.4,0,.2,1);
    opacity: 0; animation: inputFadeUp 0.7s cubic-bezier(.16,1,.3,1) forwards;
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.25);
}
.login-btn:hover {
    background: var(--btn-primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 12px 40px rgba(99, 102, 241, 0.35);
}
.login-btn:active {
    transform: translateY(0) scale(0.98);
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.2);
}
.login-btn::after {
    content: ''; position: absolute; width: 100%; height: 100%; top: 0; left: 0;
    background: radial-gradient(circle, rgba(255,255,255,0.15) 0%, transparent 60%);
    transform: scale(0); transition: transform 0.5s; border-radius: inherit;
}
.login-btn:active::after { transform: scale(2.5); transition: transform 0s; }

.login-right {
    flex: 1; display: flex; align-items: center; justify-content: center;
    position: relative; z-index: 1; padding: 40px;
}
.login-hero-image {
    width: 100%; max-width: 520px; aspect-ratio: 1 / 1;
    border-radius: 36px; overflow: hidden;
    box-shadow: var(--glass-shadow);
    animation: imageSlideIn 1s cubic-bezier(.16,1,.3,1) 0.2s forwards;
    opacity: 0;
}
@keyframes imageSlideIn {
    from { transform: translateX(50px) scale(0.95); opacity: 0; }
    to { transform: translateX(0) scale(1); opacity: 1; }
}
.login-hero-image img {
    width: 100%; height: 100%; object-fit: cover; display: block;
    transition: transform 0.6s cubic-bezier(.4,0,.2,1);
}
.login-hero-image:hover img { transform: scale(1.03); }

@media (max-width: 960px) {
    .auth-overlay { flex-direction: column; }
    .login-left { flex: none; padding: 40px 30px 20px; }
    .login-welcome-title { font-size: 42px; margin-bottom: 24px; }
    .login-right { flex: none; padding: 20px 30px 40px; order: -1; }
    .login-hero-image { max-width: 280px; border-radius: 28px; }
}
@media (max-width: 480px) {
    .login-left { padding: 24px 20px 16px; }
    .login-welcome-title { font-size: 36px; }
    .login-right { padding: 16px 20px; }
    .login-hero-image { max-width: 200px; border-radius: 24px; }
    .login-input { padding: 16px 18px 16px 48px; font-size: 15px; border-radius: 40px; }
    .login-btn { padding: 16px 24px; font-size: 16px; max-width: 100%; }
}

/* ============================================
   FORMS — Glass Inputs
   ============================================ */
.form-group { margin-bottom: 18px; }
.form-group label { display: block; font-size: 13px; font-weight: 600; color: var(--text-secondary); margin-bottom: 6px; }

.form-control {
    width: 100%; padding: 10px 14px; font-size: 14px;
    border: 1.5px solid var(--input-border);
    border-radius: var(--radius-sm);
    background: var(--input-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    color: var(--text);
    transition: border-color .2s, box-shadow .2s;
    outline: none;
}
.form-control::placeholder { color: var(--text-muted); }
.form-control:focus { border-color: var(--input-focus); box-shadow: var(--input-focus-glow); }
select.form-control { cursor: pointer; }
textarea.form-control { resize: vertical; min-height: 80px; }

/* ============================================
   BUTTONS — Glass Buttons
   ============================================ */
.btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 10px 20px; font-size: 14px; font-weight: 600;
    border-radius: var(--radius-sm);
    transition: all .25s cubic-bezier(.4,0,.2,1);
    border: 1.5px solid transparent;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}
.btn-primary {
    background: var(--btn-primary-bg); color: #fff; border-color: var(--btn-primary-border);
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.2);
}
.btn-primary:hover {
    background: var(--btn-primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.3);
}
.btn-secondary { background: var(--secondary); color: var(--text); border-color: var(--border); }
.btn-secondary:hover { background: var(--surface-hover); }
.btn-outline {
    background: rgba(255,255,255,0.06); color: var(--primary); border-color: var(--primary-glow);
    border-color: var(--input-border);
}
.btn-outline:hover { background: var(--primary-glow); }
.btn-danger {
    background: rgba(248,113,113,0.2); color: var(--danger); border-color: rgba(248,113,113,0.4);
}
.btn-danger:hover { background: rgba(248,113,113,0.35); transform: translateY(-1px); }
.btn-block { width: 100%; justify-content: center; }
.btn-lg { padding: 12px 24px; font-size: 15px; }
.btn-sm { padding: 6px 12px; font-size: 12px; }
.btn-icon-only { padding: 6px 10px; }
.btn:disabled { opacity: .4; cursor: not-allowed; }

.checkbox-grid { display: flex; flex-wrap: wrap; gap: 8px; }
.checkbox-label, .subject-checkbox-label {
    display: flex; align-items: center; gap: 6px;
    padding: 6px 12px; background: var(--secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm); cursor: pointer; font-size: 13px;
    transition: all .2s;
}
.checkbox-label:hover, .subject-checkbox-label:hover { background: var(--primary-glow); border-color: var(--primary); }

/* ============================================
   APP LAYOUT
   ============================================ */
.app-wrapper { display: flex; min-height: 100vh; position: relative; z-index: 1; }

/* ============================================
   SIDEBAR — Glass Panel
   ============================================ */
.sidebar {
    width: var(--sidebar-width);
    background: var(--sidebar-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border-right: 1px solid var(--sidebar-border);
    display: flex; flex-direction: column;
    position: fixed; top: 0; left: 0; bottom: 0;
    z-index: 100; transition: width var(--transition);
    overflow: hidden;
}
.sidebar.collapsed { width: var(--sidebar-collapsed); }
.sidebar.collapsed .link-name, .sidebar.collapsed .logo-name, .sidebar.collapsed .sidebar-profile-name { display: none; }
.sidebar.collapsed .sidebar-avatar { width: 36px; height: 36px; font-size: 12px; }

.sidebar-top { padding: 18px 16px 12px; border-bottom: 1px solid var(--border); }
.hamburger-btn {
    background: none; font-size: 22px; color: var(--text-muted);
    width: 36px; height: 36px; display: flex; align-items: center; justify-content: center;
    border-radius: var(--radius-sm); transition: .2s;
}
.hamburger-btn:hover { background: var(--nav-hover-bg); color: var(--primary); }

.logo-container { display: flex; align-items: center; gap: 12px; margin-top: 12px; }
.logo-container .icon { font-size: 28px; color: var(--primary); }
.logo-name { font-size: 18px; font-weight: 700; color: var(--text); }

.sidebar-profile { display: flex; align-items: center; gap: 12px; margin-top: 12px; }
.sidebar-avatar {
    width: 44px; height: 44px; border-radius: 12px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff; display: flex; justify-content: center; align-items: center;
    font-weight: 700; font-size: 15px; overflow: hidden; flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}
.sidebar-avatar img { width: 100%; height: 100%; object-fit: cover; }
.sidebar-profile-name { font-size: 14px; font-weight: 600; color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.nav-list { list-style: none; flex: 1; overflow-y: auto; padding: 12px 8px; }
.nav-link {
    display: flex; align-items: center; gap: 12px;
    padding: 10px 14px; font-size: 14px; font-weight: 500;
    color: var(--nav-inactive);
    border-radius: var(--radius-sm);
    transition: all .2s; margin-bottom: 2px;
    border-left: 3px solid transparent;
}
.nav-link .icon { font-size: 20px; min-width: 22px; text-align: center; }
.nav-link:hover { background: var(--nav-hover-bg); color: var(--primary); }
.nav-link.active {
    background: var(--nav-active-bg); color: var(--nav-active-text);
    font-weight: 600;
    border-left-color: var(--primary);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.15);
}
.nav-link.active .icon { color: var(--nav-active-text); }

.sidebar-bottom { padding: 12px 8px; border-top: 1px solid var(--border); }
.logout-btn { color: var(--danger) !important; }
.logout-btn:hover { background: var(--danger-light) !important; }

/* ============================================
   MAIN CONTENT
   ============================================ */
.main-content {
    flex: 1; margin-left: var(--sidebar-width); min-height: 100vh;
    transition: margin-left var(--transition);
    display: flex; flex-direction: column;
    position: relative; z-index: 1;
}
.sidebar.collapsed ~ .main-content { margin-left: var(--sidebar-collapsed); }

.top-header {
    display: flex; justify-content: space-between; align-items: center;
    padding: 16px 28px;
    background: var(--header-bg);
    backdrop-filter: var(--glass-blur);
    -webkit-backdrop-filter: var(--glass-blur);
    border-bottom: 1px solid var(--border);
    position: sticky; top: 0; z-index: 50;
}
.header-title h1 { font-size: 20px; font-weight: 700; }

.header-right { display: flex; align-items: center; gap: 14px; }
.header-search {
    display: flex; align-items: center; gap: 8px;
    background: var(--input-bg);
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm); padding: 7px 14px;
}
.header-search i { color: var(--text-muted); font-size: 18px; }
.header-search input { border: none; background: transparent; outline: none; font-size: 14px; color: var(--text); width: 140px; }
.header-search input::placeholder { color: var(--text-muted); }

.header-icon-btn {
    position: relative;
    background: var(--secondary); border: 1px solid var(--border);
    width: 38px; height: 38px; border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    font-size: 20px; color: var(--text-muted); transition: .2s;
}
.header-icon-btn:hover { background: var(--primary-glow); color: var(--primary); border-color: var(--primary-glow); }

.time-display { font-size: 13px; color: var(--text-muted); font-weight: 500; white-space: nowrap; }
.user-profile { display: flex; align-items: center; gap: 10px; }
.user-name-text { font-size: 14px; font-weight: 600; color: var(--text); }
.header-avatar {
    width: 38px; height: 38px; border-radius: var(--radius-sm); overflow: hidden;
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.2);
}
.header-avatar img { width: 100%; height: 100%; object-fit: cover; }

/* ============================================
   NOTIFICATION DROPDOWN
   ============================================ */
.notif-wrapper { position: relative; }
.notif-badge {
    position: absolute; top: -4px; right: -4px;
    width: 20px; height: 20px; border-radius: 50%;
    background: var(--danger); color: #fff;
    font-size: 10px; font-weight: 700;
    display: flex; align-items: center; justify-content: center; z-index: 2;
}

.notif-dropdown {
    position: absolute; top: calc(100% + 8px); right: 0; width: 360px;
    background: var(--glass-bg);
    backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    box-shadow: var(--glass-shadow);
    display: none; z-index: 1000;
    max-height: 420px; overflow: hidden;
}
.notif-dropdown.active { display: block; animation: fadeIn .15s; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(-4px); } to { opacity: 1; transform: translateY(0); } }

.notif-dropdown-header { display: flex; justify-content: space-between; align-items: center; padding: 14px 16px; border-bottom: 1px solid var(--border); }
.notif-dropdown-header h4 { font-size: 15px; font-weight: 700; }
.notif-dropdown-body { max-height: 340px; overflow-y: auto; padding: 4px 0; }
.notif-item { display: flex; align-items: flex-start; gap: 12px; padding: 12px 16px; transition: background .15s; cursor: pointer; }
.notif-item:hover { background: var(--surface-hover); }
.notif-item.unread { background: var(--primary-glow); }
.notif-icon { font-size: 20px; color: var(--primary); margin-top: 2px; }
.notif-content p { font-size: 13px; color: var(--text); line-height: 1.4; }
.notif-time { font-size: 11px; color: var(--text-muted); margin-top: 2px; }
.notif-empty { text-align: center; color: var(--text-muted); padding: 32px; font-size: 13px; }

/* ============================================
   VIEWS
   ============================================ */
.views-container { padding: 24px 28px; flex: 1; }
.view { display: none; animation: viewFade .3s; }
.view.active { display: block; }
@keyframes viewFade { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }

.view-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 24px; }
.view-header h2 { font-size: 20px; font-weight: 700; }
.header-actions { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

/* ============================================
   STAT CARDS — Glass Dashboard
   ============================================ */
.dashboard-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 18px; }
.stat-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 20px; display: flex; align-items: center; gap: 16px;
    transition: transform .2s, box-shadow .2s;
    box-shadow: var(--glass-shadow);
}
.stat-card:hover { transform: translateY(-3px); box-shadow: 0 12px 40px rgba(99,102,241,0.15); }
.stat-icon {
    width: 52px; height: 52px; border-radius: 14px;
    display: flex; align-items: center; justify-content: center;
    font-size: 24px; flex-shrink: 0;
    background: var(--primary-glow); color: var(--primary);
}
.stat-icon.income { background: var(--success-light); color: var(--success); }
.stat-icon.teacher-icon { background: var(--warning-light); color: var(--warning); }
.stat-icon.danger { background: var(--danger-light); color: var(--danger); }
.stat-details h3 { font-size: 13px; color: var(--text-muted); font-weight: 500; }
.stat-value { font-size: 22px; font-weight: 700; margin-top: 4px; }

/* ============================================
   TABLE CARD — Glass Tables
   ============================================ */
.table-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--glass-shadow);
}
.card-header { padding: 16px 20px; border-bottom: 1px solid var(--border); }
.card-header h2, .card-header h3 { font-size: 16px; font-weight: 700; }
.table-responsive { overflow-x: auto; }

.data-table { width: 100%; border-collapse: collapse; }
.data-table th {
    background: var(--table-header-bg); padding: 12px 16px;
    text-align: left; font-size: 12px;
    text-transform: uppercase; letter-spacing: .5px;
    color: var(--table-header-text); font-weight: 600;
}
.data-table td { padding: 12px 16px; border-bottom: 1px solid var(--table-row-border); font-size: 13px; color: var(--text-secondary); }
.data-table tr:last-child td { border-bottom: none; }
.data-table tr:hover td { background: var(--table-row-hover); }

.status-badge { display: inline-flex; padding: 4px 10px; border-radius: 20px; font-size: 11px; font-weight: 600; }
.status-badge.paid { background: var(--success-light); color: var(--success); }
.status-badge.unpaid { background: var(--danger-light); color: var(--danger); }

/* ============================================
   TEACHER DASHBOARD — Glass Stats
   ============================================ */
.teacher-dash-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.teacher-dash-title { font-size: 20px; font-weight: 700; }
.time-filter-wrapper { display: flex; align-items: center; gap: 10px; }
.time-filter-select {
    padding: 8px 14px;
    border: 1.5px solid var(--input-border); border-radius: var(--radius-sm);
    background: var(--input-bg);
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    color: var(--text); font-size: 13px; font-weight: 500;
    outline: none; cursor: pointer;
}

.teacher-stats-row { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 16px; margin-bottom: 24px; }

.t-stat-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); padding: 20px;
    display: flex; flex-direction: column; gap: 12px;
    transition: transform .2s;
    box-shadow: var(--glass-shadow);
}
.t-stat-card:hover { transform: translateY(-3px); box-shadow: 0 12px 40px rgba(99,102,241,0.15); }
.t-stat-icon-wrap { width: 40px; height: 40px; border-radius: 10px; display: flex; align-items: center; justify-content: center; font-size: 20px; color: #fff; }
.blue-bg { background: linear-gradient(135deg, #818cf8, #6366f1); }
.purple-bg { background: linear-gradient(135deg, #a78bfa, #7c3aed); }
.orange-bg { background: linear-gradient(135deg, #fbbf24, #f59e0b); }
.green-bg { background: linear-gradient(135deg, #34d399, #10b981); }
.t-stat-info { display: flex; flex-direction: column; }
.t-stat-label { font-size: 12px; color: var(--text-muted); font-weight: 500; text-transform: uppercase; letter-spacing: .5px; }
.t-stat-value { font-size: 24px; font-weight: 700; margin-top: 2px; }
.t-stat-subtitle { font-size: 12px; color: var(--text-muted); }
.t-stat-progress { height: 6px; background: var(--secondary); border-radius: 6px; overflow: hidden; }
.t-stat-bar { height: 100%; border-radius: 6px; transition: width .8s ease; }
.blue-bar { background: linear-gradient(90deg, #818cf8, #6366f1); }
.purple-bar { background: linear-gradient(90deg, #a78bfa, #7c3aed); }
.orange-bar { background: linear-gradient(90deg, #fbbf24, #f59e0b); }
.green-bar { background: linear-gradient(90deg, #34d399, #10b981); }

.teacher-charts-row { display: grid; grid-template-columns: 2fr 1fr; gap: 18px; margin-bottom: 24px; }
.chart-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); padding: 20px;
    box-shadow: var(--glass-shadow);
}
.chart-card-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px; }
.chart-card-header h3 { font-size: 15px; font-weight: 700; }
.chart-container { height: 260px; }
.chart-legend { font-size: 12px; color: var(--text-muted); display: flex; align-items: center; gap: 8px; }
.legend-dot { width: 8px; height: 8px; border-radius: 50%; display: inline-block; }
.blue-dot { background: #818cf8; }
.green-dot { background: #34d399; }

.donut-container { position: relative; height: 180px; display: flex; justify-content: center; }
.donut-center { position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); text-align: center; }
.donut-total { font-size: 14px; font-weight: 700; display: block; }
.donut-label { font-size: 10px; color: var(--text-muted); }

.revenue-rows { margin-top: 16px; }
.rev-row { display: flex; justify-content: space-between; align-items: center; padding: 10px 0; border-bottom: 1px solid var(--border); font-size: 13px; }
.rev-row:last-child { border-bottom: none; }
.rev-label { color: var(--text-muted); }
.rev-value { font-weight: 600; }
.rev-change { font-size: 11px; font-weight: 600; padding: 2px 8px; border-radius: 10px; }
.rev-change.positive { background: var(--success-light); color: var(--success); }
.rev-change.negative { background: var(--danger-light); color: var(--danger); }

.teacher-bottom-row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.bottom-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); padding: 20px;
    box-shadow: var(--glass-shadow);
}
.bottom-card-header { margin-bottom: 16px; }
.bottom-card-header h3 { font-size: 15px; font-weight: 700; }
.bottom-card-footer { margin-top: 16px; text-align: center; }
.view-all-link { font-size: 13px; color: var(--primary); font-weight: 600; display: inline-flex; align-items: center; gap: 4px; }
.view-all-link:hover { text-decoration: underline; }

.leaderboard-row { display: flex; align-items: center; gap: 12px; padding: 10px 0; border-bottom: 1px solid var(--border); }
.leaderboard-row:last-child { border-bottom: none; }
.leaderboard-rank { font-size: 14px; font-weight: 700; color: var(--primary); min-width: 24px; text-align: center; }
.leaderboard-info { flex: 1; }
.leaderboard-name { font-size: 13px; font-weight: 600; }
.leaderboard-count { font-size: 11px; color: var(--text-muted); }
.leaderboard-bar-wrap { width: 60px; height: 6px; background: var(--secondary); border-radius: 6px; overflow: hidden; }
.leaderboard-bar { height: 100%; border-radius: 6px; }
.lb-bar-green { background: var(--success); }
.lb-bar-orange { background: var(--warning); }
.lb-bar-red { background: var(--danger); }

.schedule-list { display: flex; flex-direction: column; gap: 8px; }
.schedule-item {
    display: flex; justify-content: space-between; align-items: center;
    padding: 12px 16px; background: var(--secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
}
.schedule-subject { font-size: 13px; font-weight: 600; }
.schedule-time { font-size: 12px; color: var(--text-muted); }
.schedule-empty { text-align: center; color: var(--text-muted); padding: 28px; font-size: 13px; }

/* ============================================
   ATTENDANCE SCHEDULE LIST
   ============================================ */
.attendance-schedule-list { padding: 12px 16px; display: flex; flex-direction: column; gap: 10px; }
.attendance-schedule-item {
    display: flex; justify-content: space-between; align-items: center;
    padding: 16px 20px;
    background: var(--secondary); border: 1px solid var(--border);
    border-radius: var(--radius); border-left: 4px solid var(--text-muted);
    transition: .2s;
}
.attendance-schedule-item.schedule-open { border-left-color: var(--success); background: rgba(52,211,153,.08); }
.attendance-schedule-item.schedule-locked { border-left-color: var(--danger); opacity: .7; }
.schedule-item-info { display: flex; flex-direction: column; gap: 4px; }
.schedule-item-info strong { font-size: 14px; }
.schedule-item-status { display: flex; align-items: center; gap: 6px; }

.attendance-toggle { display: flex; gap: 6px; }
.att-btn {
    padding: 6px 14px; border-radius: 6px; font-size: 12px; font-weight: 600;
    display: inline-flex; align-items: center; gap: 4px;
    background: var(--secondary); color: var(--text-muted);
    border: 1.5px solid var(--border); transition: .2s;
}
.att-btn.present.active { background: var(--success-light); color: var(--success); border-color: var(--success); }
.att-btn.absent.active { background: var(--danger-light); color: var(--danger); border-color: var(--danger); }

/* ============================================
   CHAT UI — Glass WhatsApp Style
   ============================================ */
.chat-container {
    display: flex; height: calc(100vh - 170px);
    border: 1px solid var(--glass-border); border-radius: var(--radius); overflow: hidden;
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    box-shadow: var(--glass-shadow);
}

.chat-sidebar { width: 300px; border-right: 1px solid var(--border); display: flex; flex-direction: column; background: transparent; }
.chat-sidebar-header { display: flex; justify-content: space-between; align-items: center; padding: 16px; border-bottom: 1px solid var(--border); }
.chat-sidebar-header h3 { font-size: 16px; font-weight: 700; }
.chat-group-list { flex: 1; overflow-y: auto; }

.chat-group-item { display: flex; align-items: center; gap: 12px; padding: 14px 16px; cursor: pointer; transition: background .15s; border-bottom: 1px solid var(--border); }
.chat-group-item:hover { background: var(--surface-hover); }
.chat-group-item.active { background: var(--primary-glow); border-left: 3px solid var(--primary); }

.chat-group-avatar {
    width: 44px; height: 44px; border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff; display: flex; align-items: center; justify-content: center;
    font-weight: 700; font-size: 18px; flex-shrink: 0;
}
.chat-group-info { flex: 1; min-width: 0; }
.chat-group-title { font-size: 14px; font-weight: 600; display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.chat-group-last { font-size: 12px; color: var(--text-muted); display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.chat-main { flex: 1; display: flex; flex-direction: column; }
.chat-main-header { display: flex; justify-content: space-between; align-items: center; padding: 14px 20px; border-bottom: 1px solid var(--border); }
.chat-main-title h3 { font-size: 16px; font-weight: 700; }
.chat-member-count { font-size: 12px; color: var(--text-muted); }
.chat-main-actions { display: flex; gap: 8px; }

.chat-messages { flex: 1; overflow-y: auto; padding: 20px; display: flex; flex-direction: column; gap: 8px; background: transparent; }
.chat-empty { display: flex; flex-direction: column; align-items: center; justify-content: center; height: 100%; color: var(--text-muted); gap: 12px; }

.chat-message { max-width: 70%; padding: 10px 14px; border-radius: 16px; font-size: 14px; line-height: 1.5; position: relative; word-wrap: break-word; }
.chat-msg-mine {
    align-self: flex-end;
    background: var(--chat-mine-bg);
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    color: var(--text); border-bottom-right-radius: 4px;
    border: 1px solid rgba(129,140,248,0.2);
}
.chat-msg-other {
    align-self: flex-start;
    background: var(--chat-other-bg);
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--border); border-bottom-left-radius: 4px;
}
.chat-msg-sender { font-size: 11px; font-weight: 700; color: var(--primary); display: block; margin-bottom: 2px; }
.chat-msg-text { display: block; }
.chat-msg-time { font-size: 10px; display: block; text-align: right; margin-top: 4px; opacity: .55; }
.chat-msg-image { max-width: 240px; max-height: 200px; border-radius: 8px; margin: 4px 0; display: block; }
.chat-msg-file { display: flex; align-items: center; gap: 6px; padding: 8px 12px; background: rgba(255,255,255,0.06); border-radius: 8px; font-size: 12px; margin: 4px 0; }
.chat-pin-btn { border: none; background: var(--secondary); padding: 2px 8px; border-radius: 4px; font-size: 10px; color: var(--primary); cursor: pointer; margin-top: 4px; }
.chat-pin-btn:hover { background: var(--primary-glow); }

.chat-input-bar {
    display: flex; align-items: center; gap: 8px; padding: 12px 16px;
    border-top: 1px solid var(--border); background: transparent;
}
.chat-attach-btn { cursor: pointer; font-size: 22px; color: var(--text-muted); padding: 4px; transition: .2s; display: flex; align-items: center; }
.chat-attach-btn:hover { color: var(--primary); }
.chat-input {
    flex: 1; padding: 10px 16px;
    border: 1.5px solid var(--input-border); border-radius: 24px;
    font-size: 14px; outline: none;
    background: var(--input-bg);
    backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
    color: var(--text);
}
.chat-input::placeholder { color: var(--text-muted); }
.chat-input:focus { border-color: var(--input-focus); background: var(--surface-hover); }
.chat-send-btn {
    width: 40px; height: 40px; border-radius: 50%;
    background: var(--btn-primary-bg); border: 1px solid var(--btn-primary-border);
    color: #fff; display: flex; align-items: center; justify-content: center;
    font-size: 18px; transition: .2s;
}
.chat-send-btn:hover { background: var(--btn-primary-hover); transform: scale(1.05); }

/* ============================================
   STUDY MATERIALS — Glass
   ============================================ */
.materials-list { display: flex; flex-direction: column; gap: 16px; }

.material-group {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); overflow: hidden;
    box-shadow: var(--glass-shadow);
}
.material-group-header {
    display: flex; align-items: center; gap: 8px; padding: 16px 20px;
    cursor: pointer; user-select: none; transition: background .15s;
}
.material-group-header:hover { background: var(--surface-hover); }
.material-group-header i { transition: transform .2s; color: var(--text-muted); }
.material-group.expanded .material-group-header i { transform: rotate(90deg); }
.material-count { font-size: 12px; color: var(--text-muted); margin-left: auto; }
.material-group-body { display: none; border-top: 1px solid var(--border); }
.material-group.expanded .material-group-body { display: block; }

.material-item { display: flex; align-items: center; gap: 14px; padding: 14px 20px; border-bottom: 1px solid var(--border); transition: background .15s; }
.material-item:last-child { border-bottom: none; }
.material-item:hover { background: var(--surface-hover); }
.material-item-icon { width: 42px; height: 42px; border-radius: 10px; display: flex; align-items: center; justify-content: center; font-size: 20px; color: var(--primary); background: var(--primary-glow); flex-shrink: 0; }
.material-item-info { flex: 1; min-width: 0; }
.material-item-title { font-size: 14px; font-weight: 600; display: block; }
.material-item-meta { font-size: 11px; color: var(--text-muted); margin-top: 2px; display: block; }
.material-note-content { font-size: 13px; color: var(--text-secondary); margin-top: 6px; line-height: 1.4; max-height: 60px; overflow: hidden; }
.material-item-actions { display: flex; gap: 8px; flex-shrink: 0; }

/* ============================================
   SUBJECT SELECTOR TREE
   ============================================ */
.subject-selector-tree {
    max-height: 400px; overflow-y: auto;
    border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 12px;
    background: var(--secondary);
}

.subject-group { margin-bottom: 4px; }
.subject-group-header { display: flex; align-items: center; gap: 6px; padding: 8px 10px; cursor: pointer; border-radius: var(--radius-sm); transition: background .15s; user-select: none; }
.subject-group-header:hover { background: var(--surface-hover); }
.subject-group-header i { transition: transform .2s; color: var(--text-muted); font-size: 16px; }
.subject-group.expanded > .subject-group-header i { transform: rotate(90deg); }
.subject-group-header strong { font-size: 13px; }
.subject-group-body { display: none; padding-left: 20px; margin-top: 4px; }
.subject-group.expanded > .subject-group-body { display: block; }

.subject-checkbox-label { font-size: 13px; padding: 5px 8px; margin-bottom: 2px; border-radius: 4px; }
.subject-checkbox-label input { margin-right: 6px; }
.depth-0 > .subject-group-header strong { font-size: 14px; color: var(--primary); }
.depth-1 > .subject-group-header strong { font-size: 13px; }
.depth-2 > .subject-group-header strong { font-size: 12px; color: var(--text-secondary); }

/* ============================================
   SUBJECT CARDS (My Subjects Page)
   ============================================ */
.subject-cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 18px;
}
.subject-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); padding: 20px;
    position: relative; transition: transform .2s, box-shadow .2s;
    border-top: 3px solid var(--primary);
    box-shadow: var(--glass-shadow);
}
.subject-card:hover { transform: translateY(-3px); box-shadow: 0 12px 40px rgba(99,102,241,0.18); }
.subject-card-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 8px; }
.subject-card-name { font-size: 15px; font-weight: 700; color: var(--text); line-height: 1.3; flex: 1; margin-right: 8px; }
.subject-card-delete { background: none; border: none; color: var(--text-muted); font-size: 18px; padding: 4px; border-radius: 6px; transition: all .2s; cursor: pointer; flex-shrink: 0; }
.subject-card-delete:hover { color: var(--danger); background: var(--danger-light); }
.subject-card-badge {
    display: inline-block; padding: 3px 10px;
    background: var(--primary-glow);
    color: var(--primary); font-size: 11px; font-weight: 600;
    border-radius: 20px; margin-bottom: 14px;
}
.subject-card-stats { display: flex; gap: 16px; }
.subject-card-stat { display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--text-secondary); }
.subject-card-stat i { font-size: 16px; color: var(--text-muted); }
.subject-empty-state { display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 60px 20px; text-align: center; }

/* ============================================
   WIZARD STEPS (Add Subject Modal)
   ============================================ */
.wizard-steps { display: flex; align-items: center; justify-content: center; gap: 0; margin-bottom: 28px; padding: 0 10px; }
.wizard-step { display: flex; flex-direction: column; align-items: center; gap: 4px; position: relative; }
.wizard-step-num {
    width: 32px; height: 32px; border-radius: 50%;
    background: var(--secondary); color: var(--text-muted);
    font-size: 13px; font-weight: 700;
    display: flex; align-items: center; justify-content: center;
    border: 2px solid var(--border); transition: all .3s;
}
.wizard-step.active .wizard-step-num { background: var(--primary); color: #fff; border-color: var(--primary); box-shadow: 0 2px 12px rgba(99,102,241,0.35); }
.wizard-step-label { font-size: 11px; color: var(--text-muted); font-weight: 500; white-space: nowrap; }
.wizard-step.active .wizard-step-label { color: var(--primary); font-weight: 600; }
.wizard-step-line { width: 40px; height: 2px; background: var(--border); margin: 0 6px; margin-bottom: 18px; border-radius: 2px; }
.wizard-panel { display: none; animation: viewFade .25s; }
.wizard-panel.active { display: block; }
.wizard-label { display: block; font-size: 14px; font-weight: 600; color: var(--text); margin-bottom: 14px; }

.grade-btn-group { display: flex; flex-wrap: wrap; gap: 10px; }
.grade-select-btn {
    padding: 12px 20px; border-radius: var(--radius-sm);
    font-size: 13px; font-weight: 600;
    background: var(--secondary); color: var(--text);
    border: 1.5px solid var(--border); cursor: pointer;
    transition: all .2s; flex: 1; min-width: 120px; text-align: center;
}
.grade-select-btn:hover { background: var(--primary-glow); border-color: var(--primary); color: var(--primary); }
.grade-select-btn.selected { background: var(--primary); color: #fff; border-color: var(--primary); box-shadow: 0 2px 12px rgba(99,102,241,0.3); }

.subject-pick-area { max-height: 320px; overflow-y: auto; border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 12px; background: var(--secondary); }
.subject-pick-area .subject-checkbox-label { margin-bottom: 4px; }

.add-sub-summary { border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 16px; max-height: 300px; overflow-y: auto; }
.summary-badge {
    display: inline-block; padding: 5px 14px;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: #fff; font-size: 12px; font-weight: 700; border-radius: 20px; margin-bottom: 14px;
}
.summary-item { display: flex; align-items: center; gap: 8px; padding: 8px 0; border-bottom: 1px solid var(--border); font-size: 13px; color: var(--text); }
.summary-item:last-child { border-bottom: none; }
.summary-item i { color: var(--primary); font-size: 16px; }

/* ============================================
   SETTINGS — Glass Cards
   ============================================ */
.settings-container { display: flex; flex-direction: column; gap: 20px; }
.settings-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); padding: 24px;
    box-shadow: var(--glass-shadow);
}
.settings-card h3 { font-size: 16px; font-weight: 700; margin-bottom: 16px; }
.settings-row { display: flex; align-items: center; gap: 16px; padding: 12px 0; }
.settings-label { display: flex; align-items: center; gap: 8px; font-size: 14px; font-weight: 500; min-width: 120px; }
.settings-label i { font-size: 20px; color: var(--text-muted); }

.theme-toggle-group { display: flex; gap: 8px; }
.theme-btn {
    padding: 8px 18px; border-radius: var(--radius-sm);
    font-size: 13px; font-weight: 600;
    display: inline-flex; align-items: center; gap: 6px;
    background: var(--secondary); color: var(--text-muted);
    border: 1.5px solid var(--border); transition: .2s;
}
.theme-btn.active { background: var(--primary); color: #fff; border-color: var(--primary); box-shadow: 0 2px 8px rgba(99,102,241,0.25); }
.theme-btn:hover:not(.active) { background: var(--surface-hover); color: var(--text); }

.photo-upload-row { flex-wrap: wrap; }
.photo-preview { width: 72px; height: 72px; border-radius: 16px; background: var(--secondary); display: flex; align-items: center; justify-content: center; overflow: hidden; font-size: 28px; color: var(--text-muted); border: 1px solid var(--border); }
.photo-preview img { width: 100%; height: 100%; object-fit: cover; }
.photo-upload-actions { display: flex; flex-direction: column; gap: 8px; }
.photo-hint { font-size: 11px; color: var(--text-muted); }

/* Settings Panel (overlay) */
.settings-panel-overlay { position: fixed; inset: 0; z-index: 500; background: var(--modal-overlay); backdrop-filter: blur(4px); -webkit-backdrop-filter: blur(4px); display: none; justify-content: flex-end; }
.settings-panel-overlay.active { display: flex; }
.settings-panel {
    width: 360px; height: 100%;
    background: var(--modal-bg);
    backdrop-filter: blur(30px); -webkit-backdrop-filter: blur(30px);
    border-left: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow); padding: 24px;
    animation: slideInRight .25s ease;
}
@keyframes slideInRight { from { transform: translateX(100%); } to { transform: translateX(0); } }
.settings-panel-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 24px; }
.settings-panel-header h3 { font-size: 18px; font-weight: 700; }
.close-btn {
    background: var(--secondary); width: 32px; height: 32px; border-radius: var(--radius-sm);
    display: flex; align-items: center; justify-content: center;
    font-size: 18px; color: var(--text-muted); transition: .2s;
    border: 1px solid var(--border);
}
.close-btn:hover { background: var(--danger-light); color: var(--danger); border-color: rgba(248,113,113,0.3); }

/* ============================================
   MODAL — Frosted Glass Modals
   ============================================ */
.modal-overlay {
    position: fixed; inset: 0; z-index: 1000;
    background: var(--modal-overlay);
    backdrop-filter: blur(6px); -webkit-backdrop-filter: blur(6px);
    display: none; justify-content: center; align-items: center;
}
.modal-overlay.active { display: flex; }
.modal {
    background: var(--modal-bg);
    backdrop-filter: blur(30px); -webkit-backdrop-filter: blur(30px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius); width: 100%; max-width: 480px; max-height: 85vh;
    overflow-y: auto;
    box-shadow: var(--glass-shadow);
    display: none; animation: modalIn .25s;
}
.modal.active { display: block; }
@keyframes modalIn { from { transform: scale(0.95) translateY(10px); opacity: 0; } to { transform: scale(1) translateY(0); opacity: 1; } }
.modal-header { display: flex; justify-content: space-between; align-items: center; padding: 18px 24px; border-bottom: 1px solid var(--border); }
.modal-header h3 { font-size: 17px; font-weight: 700; }
.modal-body { padding: 24px; }

/* ============================================
   RESPONSIVE — Tablets & Laptops
   ============================================ */
@media (max-width: 1024px) {
    .teacher-charts-row { grid-template-columns: 1fr; }
    .teacher-bottom-row { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .sidebar { width: var(--sidebar-collapsed); }
    .sidebar .link-name, .sidebar .logo-name, .sidebar .sidebar-profile-name { display: none; }
    .sidebar-avatar { width: 36px; height: 36px; font-size: 12px; }
    .main-content { margin-left: var(--sidebar-collapsed); }
    .top-header { padding: 10px 14px; flex-wrap: wrap; gap: 8px; }
    .header-title h1 { font-size: 16px; }
    .header-search { display: none; }
    .header-right { gap: 8px; }
    .time-display { display: none; }
    .user-name-text { display: none; }
    .header-avatar { width: 32px; height: 32px; }
    .header-icon-btn { width: 34px; height: 34px; font-size: 18px; }
    .views-container { padding: 14px; }
    .view-header { flex-direction: column; gap: 10px; align-items: flex-start; }
    .view-header h2 { font-size: 18px; }
    .header-actions { width: 100%; flex-wrap: wrap; }
    .header-actions .form-control { min-width: 0 !important; flex: 1; }
    .dashboard-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
    .stat-card { padding: 14px; gap: 12px; }
    .stat-icon { width: 44px; height: 44px; font-size: 20px; border-radius: 12px; }
    .stat-value { font-size: 18px; }
    .stat-details h3 { font-size: 12px; }
    .teacher-stats-row { grid-template-columns: 1fr 1fr; gap: 12px; }
    .t-stat-card { padding: 16px; }
    .t-stat-value { font-size: 20px; }
    .data-table th, .data-table td { padding: 10px 12px; font-size: 12px; }
    .table-card { border-radius: 12px; }
    .chat-container { height: calc(100vh - 130px); }
    .chat-sidebar { width: 72px; }
    .chat-group-info { display: none; }
    .chat-group-avatar { width: 38px; height: 38px; font-size: 15px; }
    .chat-group-item { padding: 12px; justify-content: center; }
    .chat-messages { padding: 14px; }
    .chat-message { max-width: 85%; font-size: 13px; padding: 8px 12px; }
    .chat-main-header { padding: 10px 14px; }
    .chat-input-bar { padding: 10px 12px; }
    .modal { max-width: calc(100% - 24px); margin: 12px; border-radius: 16px; }
    .modal-header { padding: 14px 18px; }
    .modal-header h3 { font-size: 15px; }
    .modal-body { padding: 18px; }
    .settings-panel { width: 100%; max-width: 320px; padding: 20px; }
    .notif-dropdown { width: calc(100vw - 24px); right: -60px; }
}

@media (max-width: 480px) {
    .sidebar { position: fixed; width: var(--sidebar-collapsed); z-index: 200; }
    .main-content { margin-left: var(--sidebar-collapsed); }
    .top-header { padding: 8px 12px; }
    .header-title h1 { font-size: 15px; }
    .views-container { padding: 10px; }
    .view-header h2 { font-size: 16px; }
    .dashboard-grid { grid-template-columns: 1fr; gap: 10px; }
    .stat-card { padding: 12px; }
    .stat-icon { width: 40px; height: 40px; font-size: 18px; border-radius: 10px; }
    .stat-value { font-size: 16px; }
    .teacher-stats-row { grid-template-columns: 1fr; gap: 10px; }
    .t-stat-card { padding: 14px; }
    .t-stat-value { font-size: 18px; }
    .teacher-dash-header { flex-direction: column; gap: 10px; align-items: flex-start; }
    .teacher-dash-title { font-size: 18px; }
    .time-filter-select { width: 100%; }
    .chart-container { height: 200px; }
    .chart-card { padding: 14px; }
    .donut-container { height: 150px; }
    .rev-row { flex-wrap: wrap; gap: 4px; padding: 8px 0; }
    .rev-change { margin-left: auto; }
    .data-table th, .data-table td { padding: 8px 10px; font-size: 11px; white-space: nowrap; }
    .table-responsive { -webkit-overflow-scrolling: touch; }
    .btn { padding: 8px 14px; font-size: 13px; }
    .btn-lg { padding: 10px 18px; font-size: 14px; }
    .header-actions .btn { padding: 7px 12px; font-size: 12px; }
    .form-group { margin-bottom: 14px; }
    .form-group label { font-size: 12px; }
    .form-control { padding: 9px 12px; font-size: 13px; }
    .chat-container { height: calc(100vh - 120px); flex-direction: column; }
    .chat-sidebar { width: 100%; height: auto; max-height: 100px; border-right: none; border-bottom: 1px solid var(--border); flex-direction: row; overflow-x: auto; overflow-y: hidden; }
    .chat-sidebar-header { display: none; }
    .chat-group-list { display: flex; flex-direction: row; gap: 4px; padding: 8px; }
    .chat-group-item { padding: 8px 10px; border-bottom: none; border-radius: var(--radius-sm); min-width: fit-content; }
    .chat-group-avatar { width: 34px; height: 34px; font-size: 14px; }
    .chat-main { min-height: 0; }
    .chat-messages { padding: 10px; gap: 6px; }
    .chat-message { max-width: 90%; font-size: 13px; border-radius: 14px; }
    .chat-input { padding: 8px 14px; font-size: 13px; }
    .chat-send-btn { width: 36px; height: 36px; font-size: 16px; }
    .modal-overlay { align-items: flex-end; }
    .modal { max-width: 100%; max-height: 90vh; margin: 0; border-radius: 20px 20px 0 0; animation: modalSlideUp .25s ease; }
    @keyframes modalSlideUp { from { transform: translateY(100%); opacity: 0; } to { transform: translateY(0); opacity: 1; } }
    .modal-header { padding: 14px 16px; }
    .modal-header h3 { font-size: 15px; }
    .modal-body { padding: 16px; }
    .settings-container { gap: 14px; }
    .settings-card { padding: 16px; }
    .settings-card h3 { font-size: 14px; margin-bottom: 12px; }
    .settings-row { flex-direction: column; align-items: flex-start; gap: 10px; }
    .settings-label { min-width: auto; }
    .theme-toggle-group { width: 100%; }
    .theme-btn { flex: 1; justify-content: center; }
    .settings-panel { width: 100%; max-width: 100%; }
    .notif-dropdown { width: calc(100vw - 16px); right: -40px; max-height: 360px; }
    .notif-item { padding: 10px 14px; }
    .attendance-schedule-item { flex-direction: column; align-items: flex-start; gap: 8px; padding: 14px 16px; }
    .attendance-toggle { width: 100%; }
    .att-btn { flex: 1; justify-content: center; }
    .material-item { flex-direction: column; align-items: flex-start; gap: 10px; padding: 12px 16px; }
    .material-item-actions { width: 100%; justify-content: flex-end; }
    .subject-selector-tree { max-height: 300px; }
    .subject-group-header { padding: 6px 8px; }
    .checkbox-grid { gap: 6px; }
    .checkbox-label, .subject-checkbox-label { font-size: 12px; padding: 5px 10px; }
    .leaderboard-row { gap: 8px; padding: 8px 0; }
    .leaderboard-name { font-size: 12px; }
    .leaderboard-bar-wrap { width: 40px; }
    .schedule-item { padding: 10px 12px; }
    .schedule-subject { font-size: 12px; }
    .schedule-time { font-size: 11px; }
    .photo-preview { width: 60px; height: 60px; border-radius: 14px; }
}

@media (max-width: 360px) {
    .sidebar { width: 52px; }
    .main-content { margin-left: 52px; }
    .views-container { padding: 8px; }
    .stat-card { padding: 10px; }
    .stat-icon { width: 36px; height: 36px; font-size: 16px; }
    .stat-value { font-size: 15px; }
    .login-left { padding: 20px 16px 10px; }
    .login-welcome-title { font-size: 30px; }
    .login-hero-image { max-width: 160px; border-radius: 20px; }
    .login-input { padding: 14px 16px 14px 44px; font-size: 14px; }
    .login-btn { padding: 14px 20px; font-size: 15px; }
}

/* ============================================
   YOUTUBE PLAYER & ZOOM BUTTON — Materials
   ============================================ */
.yt-player-wrap {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 16:9 ratio */
    border-radius: 12px;
    overflow: hidden;
    background: #000;
    box-shadow: 0 8px 32px rgba(0,0,0,0.3);
    margin: 12px 0;
}
.yt-player-wrap iframe {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    border: none;
    border-radius: 12px;
}

.zoom-join-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: #2D8CFF;
    color: white;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 14px;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    text-decoration: none;
}
.zoom-join-btn:hover {
    background: #1a7ae8;
    transform: translateY(-2px);
    box-shadow: 0 4px 16px rgba(45,140,255,0.4);
}

.zoom-link-btn {
    background: rgba(45, 140, 255, 0.12) !important;
    border-color: rgba(45, 140, 255, 0.3) !important;
    color: #2D8CFF !important;
}
.zoom-link-btn:hover {
    background: rgba(45, 140, 255, 0.22) !important;
    border-color: #2D8CFF !important;
}

.material-teacher-name {
    display: block;
    font-size: 13px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 2px;
}

/* ============================================
   SCROLLBAR — Glass Style
   ============================================ */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(129,140,248,0.25); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: rgba(129,140,248,0.4); }

/* ============================================
   LIVE CLASSES — Glass Cards Grid
   ============================================ */
.live-classes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 18px;
}

.live-class-card {
    background: var(--glass-bg);
    backdrop-filter: var(--glass-blur); -webkit-backdrop-filter: var(--glass-blur);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: var(--glass-shadow);
    transition: transform .2s, box-shadow .2s;
    border-top: 3px solid var(--primary);
    display: flex; flex-direction: column; gap: 12px;
}
.live-class-card:hover { transform: translateY(-3px); box-shadow: 0 12px 40px rgba(99,102,241,0.18); }

.live-class-card-header { display: flex; align-items: flex-start; gap: 14px; }

.live-class-icon-wrap {
    width: 46px; height: 46px; border-radius: 12px; flex-shrink: 0;
    background: linear-gradient(135deg, var(--primary), #818cf8);
    display: flex; align-items: center; justify-content: center;
    font-size: 22px; color: #fff;
    box-shadow: 0 4px 12px rgba(99,102,241,0.3);
}

.live-class-info { flex: 1; min-width: 0; }
.live-class-title { font-size: 15px; font-weight: 700; color: var(--text); line-height: 1.3; margin: 0 0 4px; }
.live-class-date { font-size: 12px; color: var(--text-muted); }

.live-class-actions { display: flex; gap: 6px; flex-shrink: 0; }

.live-class-notes {
    font-size: 13px; color: var(--text-secondary); line-height: 1.5;
    background: var(--secondary); border-radius: 8px;
    padding: 10px 14px; margin: 0;
    border-left: 3px solid var(--primary-glow);
}

.live-class-join-btn {
    align-self: flex-start; display: inline-flex; align-items: center; gap: 6px;
}

@media (max-width: 480px) {
    .live-classes-grid { grid-template-columns: 1fr; }
    .live-class-card { padding: 16px; }
    .live-class-title { font-size: 14px; }
}