/* ============================================
   StudyTrack — Black & White Minimalist Theme
   ============================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

/* --- CSS Variables --- */
:root {
    --bg-primary: #000000;
    --bg-secondary: #0a0a0a;
    --bg-card: #111111;
    --bg-card-hover: #1a1a1a;
    --bg-input: #0d0d0d;
    --bg-sidebar: #080808;
    --border-primary: #1e1e1e;
    --border-secondary: #2d2d2d;
    --border-active: #ffffff;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --text-muted: #666666;
    --text-dim: #444444;
    --accent: #ffffff;
    --accent-hover: #e0e0e0;
    --danger: #ff4444;
    --danger-soft: rgba(255, 68, 68, 0.15);
    --success: #44ff44;
    --success-soft: rgba(68, 255, 68, 0.15);
    --warning: #ffaa00;
    --warning-soft: rgba(255, 170, 0, 0.15);
    --info: #4488ff;
    --info-soft: rgba(68, 136, 255, 0.15);
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.5);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.6);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.8);
    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --sidebar-width: 260px;
    --header-height: 64px;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

/* --- Reset --- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 14px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: var(--transition);
}

a:hover {
    color: var(--accent-hover);
}

img { max-width: 100%; }

/* --- Scrollbar --- */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--border-secondary); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }

/* ============================================
   LAYOUT
   ============================================ */

.app-wrapper {
    display: flex;
    min-height: 100vh;
}

/* --- Sidebar --- */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    width: var(--sidebar-width);
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border-primary);
    display: flex;
    flex-direction: column;
    z-index: 100;
    transition: transform 0.3s ease;
}

.sidebar-brand {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-primary);
    display: flex;
    align-items: center;
    gap: 12px;
}

.sidebar-brand .logo {
    width: 32px;
    height: 32px;
    background: var(--accent);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #000;
    font-weight: 800;
    font-size: 16px;
}

.sidebar-brand h1 {
    font-size: 18px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.sidebar-brand span {
    font-size: 11px;
    color: var(--text-muted);
    display: block;
    margin-top: 2px;
}

.sidebar-nav {
    flex: 1;
    padding: 16px 12px;
    overflow-y: auto;
}

.sidebar-nav .nav-section {
    margin-bottom: 24px;
}

.sidebar-nav .nav-label {
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
    color: var(--text-dim);
    padding: 0 12px;
    margin-bottom: 8px;
    font-weight: 600;
}

.sidebar-nav .nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    color: var(--text-secondary);
    font-size: 13px;
    font-weight: 500;
    transition: var(--transition);
    cursor: pointer;
    position: relative;
}

.sidebar-nav .nav-item:hover {
    background: var(--bg-card);
    color: var(--text-primary);
}

.sidebar-nav .nav-item.active {
    background: var(--bg-card);
    color: var(--text-primary);
}

.sidebar-nav .nav-item.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 20px;
    background: var(--accent);
    border-radius: 0 2px 2px 0;
}

.sidebar-nav .nav-item .icon {
    width: 20px;
    text-align: center;
    font-size: 16px;
    flex-shrink: 0;
}

.sidebar-nav .nav-item .badge {
    margin-left: auto;
    background: var(--border-secondary);
    color: var(--text-secondary);
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 11px;
    font-weight: 600;
}

.sidebar-user {
    padding: 16px;
    border-top: 1px solid var(--border-primary);
    display: flex;
    align-items: center;
    gap: 12px;
}

.sidebar-user .avatar {
    width: 36px;
    height: 36px;
    background: var(--border-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 14px;
    color: var(--text-primary);
    flex-shrink: 0;
}

.sidebar-user .user-info {
    flex: 1;
    overflow: hidden;
}

.sidebar-user .user-name {
    font-size: 13px;
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.sidebar-user .user-role {
    font-size: 11px;
    color: var(--text-muted);
}

/* --- Main Content --- */
.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    min-height: 100vh;
}

/* --- Top Header --- */
.top-header {
    position: sticky;
    top: 0;
    height: var(--header-height);
    background: rgba(0,0,0,0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-primary);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 32px;
    z-index: 50;
}

.top-header .page-title {
    font-size: 16px;
    font-weight: 600;
    letter-spacing: -0.3px;
}

.top-header .header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 20px;
    cursor: pointer;
    padding: 8px;
}

/* --- Page Content --- */
.page-content {
    padding: 32px;
    max-width: 1400px;
}

/* ============================================
   COMPONENTS
   ============================================ */

/* --- Cards --- */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: 24px;
    transition: var(--transition);
}

.card:hover {
    border-color: var(--border-secondary);
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.card-title {
    font-size: 14px;
    font-weight: 600;
    letter-spacing: -0.2px;
}

.card-subtitle {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* --- Stat Cards --- */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 32px;
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: 20px 24px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.stat-card:hover {
    border-color: var(--border-secondary);
    transform: translateY(-2px);
}

.stat-card .stat-icon {
    font-size: 20px;
    margin-bottom: 12px;
    display: block;
}

.stat-card .stat-value {
    font-size: 28px;
    font-weight: 800;
    letter-spacing: -1px;
    line-height: 1;
}

.stat-card .stat-label {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 6px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.stat-card .stat-change {
    font-size: 11px;
    margin-top: 8px;
    font-weight: 500;
}

.stat-card .stat-change.up { color: var(--success); }
.stat-card .stat-change.down { color: var(--danger); }

/* --- Buttons --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 600;
    font-family: var(--font);
    cursor: pointer;
    transition: var(--transition);
    border: 1px solid transparent;
    line-height: 1;
    white-space: nowrap;
}

.btn-primary {
    background: var(--accent);
    color: #000;
    border-color: var(--accent);
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border-color: var(--border-secondary);
}

.btn-secondary:hover {
    background: var(--bg-card);
    border-color: var(--text-muted);
}

.btn-danger {
    background: transparent;
    color: var(--danger);
    border-color: rgba(255,68,68,0.3);
}

.btn-danger:hover {
    background: var(--danger-soft);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    border: none;
    padding: 8px 12px;
}

.btn-ghost:hover {
    color: var(--text-primary);
    background: var(--bg-card);
}

.btn-sm {
    padding: 6px 14px;
    font-size: 12px;
}

.btn-lg {
    padding: 14px 28px;
    font-size: 15px;
}

.btn-block {
    display: flex;
    width: 100%;
}

.btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
    transform: none !important;
}

/* --- Forms --- */
.form-group {
    margin-bottom: 20px;
}

.form-label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.form-control,
.form-input,
.form-select,
.form-textarea,
input[type="text"],
input[type="email"],
input[type="password"],
input[type="date"],
input[type="datetime-local"] {
    width: 100%;
    padding: 10px 14px;
    background: #111111 !important;
    border: 1px solid var(--border-secondary) !important;
    border-radius: var(--radius-md) !important;
    color: #ffffff !important;
    font-size: 14px;
    font-family: var(--font);
    transition: var(--transition);
    outline: none;
    box-sizing: border-box;
    -webkit-text-fill-color: #ffffff;
}

.form-control:focus,
.form-input:focus,
.form-select:focus,
.form-textarea:focus,
input[type="text"]:focus,
input[type="email"]:focus,
input[type="password"]:focus,
input[type="date"]:focus,
input[type="datetime-local"]:focus {
    border-color: #ffffff !important;
    background: #181818 !important;
    color: #ffffff !important;
    box-shadow: 0 0 0 2px rgba(255,255,255,0.15) !important;
}

.form-control::placeholder,
.form-input::placeholder,
input::placeholder,
textarea::placeholder {
    color: #888888 !important;
    -webkit-text-fill-color: #888888 !important;
    opacity: 1 !important;
}

.form-control-sm {
    padding: 7px 12px !important;
    font-size: 13px !important;
}

.form-control-lg {
    padding: 12px 16px !important;
    font-size: 15px !important;
}

/* --- Dark Theme Browser Autofill Overrides --- */
input:-webkit-autofill,
input:-webkit-autofill:hover, 
input:-webkit-autofill:focus, 
input:-webkit-autofill:active,
textarea:-webkit-autofill,
select:-webkit-autofill {
    -webkit-box-shadow: 0 0 0 1000px #111111 inset !important;
    -webkit-text-fill-color: #ffffff !important;
    box-shadow: 0 0 0 1000px #111111 inset !important;
    color: #ffffff !important;
    caret-color: #ffffff !important;
    transition: background-color 5000s ease-in-out 0s;
}

.form-textarea { resize: vertical; min-height: 100px; }
.form-select { cursor: pointer; color: #ffffff !important; }
.form-select option { background: #1a1a1a !important; color: #ffffff !important; }

.form-error {
    font-size: 12px;
    color: var(--danger);
    margin-top: 6px;
}

.form-hint {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 6px;
}

/* --- Checkbox / Toggle --- */
.form-check {
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-size: 13px;
}

.form-check input[type="checkbox"] {
    appearance: none;
    width: 18px;
    height: 18px;
    border: 1px solid var(--border-secondary);
    border-radius: 4px;
    background: var(--bg-input);
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    flex-shrink: 0;
}

.form-check input[type="checkbox"]:checked {
    background: var(--accent);
    border-color: var(--accent);
}

.form-check input[type="checkbox"]:checked::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #000;
    font-size: 12px;
    font-weight: 700;
}

/* --- Tables --- */
.table-wrapper {
    overflow-x: auto;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
}

table {
    width: 100%;
    border-collapse: collapse;
}

th {
    padding: 12px 16px;
    text-align: left;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-primary);
}

td {
    padding: 14px 16px;
    font-size: 13px;
    border-bottom: 1px solid var(--border-primary);
    vertical-align: middle;
}

tr:last-child td { border-bottom: none; }

tr:hover td {
    background: var(--bg-card);
}

/* --- Task Items --- */
.task-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.task-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 14px 18px;
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-sm);
    transition: var(--transition);
    cursor: grab;
    position: relative;
}

.task-item:hover {
    border-color: var(--border-secondary);
    background: var(--bg-card-hover);
}

.task-item.completed {
    opacity: 0.5;
}

.task-item.completed .task-title {
    text-decoration: line-through;
}

.task-item .drag-handle {
    color: var(--text-dim);
    cursor: grab;
    font-size: 16px;
    flex-shrink: 0;
}

.task-item .drag-handle:active { cursor: grabbing; }

.task-item .task-check {
    flex-shrink: 0;
}

.task-item .task-info {
    flex: 1;
    min-width: 0;
}

.task-item .task-title {
    font-size: 14px;
    font-weight: 500;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.task-item .task-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 4px;
    font-size: 12px;
    color: var(--text-muted);
}

.task-item .task-actions {
    display: flex;
    gap: 4px;
    opacity: 0;
    transition: var(--transition);
}

.task-item:hover .task-actions { opacity: 1; }

.task-item .priority-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    flex-shrink: 0;
}

.priority-high { background: var(--danger); }
.priority-medium { background: var(--warning); }
.priority-low { background: var(--success); }
.priority-urgent { background: #ff0000; box-shadow: 0 0 6px rgba(255,0,0,0.5); }

/* --- SortableJS Ghost --- */
.sortable-ghost {
    opacity: 0.3;
    border: 1px dashed var(--accent) !important;
}

.sortable-chosen {
    box-shadow: var(--shadow-lg);
}

.sortable-drag {
    opacity: 0.9;
}

/* --- Badges / Tags --- */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 3px 10px;
    border-radius: 12px;
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.3px;
}

.badge-default { background: var(--border-secondary); color: var(--text-secondary); }
.badge-success { background: var(--success-soft); color: var(--success); }
.badge-danger { background: var(--danger-soft); color: var(--danger); }
.badge-warning { background: var(--warning-soft); color: var(--warning); }
.badge-info { background: var(--info-soft); color: var(--info); }

/* --- Countdown Cards --- */
.countdown-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: 24px;
    text-align: center;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.countdown-card:hover {
    border-color: var(--border-secondary);
    transform: translateY(-2px);
}

.countdown-card .cd-name {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 4px;
}

.countdown-card .cd-target {
    font-size: 11px;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.countdown-card .cd-timer {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 16px;
}

.countdown-card .cd-unit {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-width: 56px;
}

.countdown-card .cd-value {
    font-size: 32px;
    font-weight: 800;
    letter-spacing: -1px;
    line-height: 1;
    font-variant-numeric: tabular-nums;
}

.countdown-card .cd-label {
    font-size: 10px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 6px;
}

.countdown-card .cd-progress {
    width: 100%;
    height: 3px;
    background: var(--border-primary);
    border-radius: 2px;
    overflow: hidden;
}

.countdown-card .cd-progress-bar {
    height: 100%;
    background: var(--accent);
    transition: width 1s linear;
}

/* --- Alerts / Flash Messages --- */
.alert {
    padding: 14px 20px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 12px;
    animation: slideIn 0.3s ease;
}

.alert-success { background: var(--success-soft); color: var(--success); border: 1px solid rgba(68,255,68,0.2); }
.alert-error { background: var(--danger-soft); color: var(--danger); border: 1px solid rgba(255,68,68,0.2); }
.alert-warning { background: var(--warning-soft); color: var(--warning); border: 1px solid rgba(255,170,0,0.2); }
.alert-info { background: var(--info-soft); color: var(--info); border: 1px solid rgba(68,136,255,0.2); }

.alert .alert-close {
    margin-left: auto;
    cursor: pointer;
    opacity: 0.6;
    transition: var(--transition);
}
.alert .alert-close:hover { opacity: 1; }

/* --- Modal --- */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.7);
    backdrop-filter: blur(8px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    width: 90%;
    max-width: 560px;
    max-height: 85vh;
    overflow-y: auto;
    transform: scale(0.95) translateY(20px);
    transition: transform 0.3s ease;
}

.modal-overlay.active .modal {
    transform: scale(1) translateY(0);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border-primary);
}

.modal-title {
    font-size: 16px;
    font-weight: 600;
}

.modal-close {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 20px;
    cursor: pointer;
    padding: 4px;
    transition: var(--transition);
}

.modal-close:hover { color: var(--text-primary); }

.modal-body { padding: 24px; }

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 12px;
    padding: 16px 24px;
    border-top: 1px solid var(--border-primary);
}

/* --- OTP Input --- */
.otp-container {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin: 24px 0;
}

.otp-input {
    width: 52px;
    height: 60px;
    text-align: center;
    font-size: 24px;
    font-weight: 700;
    background: var(--bg-input);
    border: 2px solid var(--border-secondary);
    border-radius: var(--radius-sm);
    color: var(--text-primary);
    font-family: var(--font);
    outline: none;
    transition: var(--transition);
}

.otp-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(255,255,255,0.08);
}

/* --- Timetable Grid --- */
.timetable-grid {
    display: grid;
    grid-template-columns: 80px repeat(7, 1fr);
    gap: 1px;
    background: var(--border-primary);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    overflow: hidden;
}

.timetable-grid .tt-header {
    background: var(--bg-secondary);
    padding: 12px 8px;
    text-align: center;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
}

.timetable-grid .tt-time {
    background: var(--bg-secondary);
    padding: 12px 8px;
    text-align: center;
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
}

.timetable-grid .tt-cell {
    background: var(--bg-card);
    padding: 8px;
    min-height: 60px;
    transition: var(--transition);
    position: relative;
}

.timetable-grid .tt-cell:hover {
    background: var(--bg-card-hover);
}

.timetable-grid .tt-cell.drop-zone-active {
    background: rgba(255,255,255,0.05);
    border: 1px dashed var(--accent);
}

.tt-slot {
    background: var(--bg-primary);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-sm);
    padding: 6px 8px;
    font-size: 11px;
    cursor: grab;
    margin-bottom: 4px;
    transition: var(--transition);
}

.tt-slot:hover {
    border-color: var(--accent);
}

.tt-slot .tt-slot-subject {
    font-weight: 600;
    font-size: 12px;
}

.tt-slot .tt-slot-topic {
    color: var(--text-muted);
    margin-top: 2px;
}

/* --- Loading Spinner --- */
.spinner {
    width: 24px;
    height: 24px;
    border: 2px solid var(--border-secondary);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
}

.spinner-lg { width: 40px; height: 40px; border-width: 3px; }

.loading-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: 16px;
    z-index: 2000;
}

.loading-overlay .loading-text {
    font-size: 14px;
    color: var(--text-secondary);
    animation: pulse 1.5s ease infinite;
}

/* --- Empty State --- */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}

.empty-state .empty-icon {
    font-size: 48px;
    margin-bottom: 16px;
    opacity: 0.5;
}

.empty-state .empty-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.empty-state .empty-text {
    font-size: 13px;
    max-width: 360px;
    margin: 0 auto 20px;
}

/* --- Tabs --- */
.tabs {
    display: flex;
    gap: 4px;
    border-bottom: 1px solid var(--border-primary);
    margin-bottom: 24px;
}

.tab {
    padding: 10px 16px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-muted);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: var(--transition);
}

.tab:hover { color: var(--text-secondary); }
.tab.active {
    color: var(--text-primary);
    border-bottom-color: var(--accent);
}

/* --- Notification Toast --- */
.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 3000;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    background: var(--bg-card);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-sm);
    padding: 14px 20px;
    min-width: 300px;
    max-width: 420px;
    box-shadow: var(--shadow-lg);
    animation: slideInRight 0.3s ease;
    display: flex;
    align-items: center;
    gap: 12px;
}

.toast.toast-success { border-left: 3px solid var(--success); }
.toast.toast-error { border-left: 3px solid var(--danger); }
.toast.toast-warning { border-left: 3px solid var(--warning); }

/* --- Calendar overrides (FullCalendar) --- */
.fc {
    --fc-border-color: var(--border-primary);
    --fc-bg-color: var(--bg-card);
    --fc-text-color: var(--text-primary);
    --fc-event-bg-color: var(--border-secondary);
    --fc-event-border-color: var(--accent);
    --fc-today-bg-color: rgba(255,255,255,0.03);
    font-family: var(--font) !important;
}

.fc .fc-button {
    background: var(--bg-card) !important;
    border-color: var(--border-secondary) !important;
    color: var(--text-primary) !important;
    font-size: 12px !important;
}

.fc .fc-button:hover {
    background: var(--bg-card-hover) !important;
}

.fc .fc-button-active {
    background: var(--accent) !important;
    color: #000 !important;
}

.fc .fc-col-header-cell {
    background: var(--bg-secondary);
    font-size: 11px;
    text-transform: uppercase;
}

.fc .fc-daygrid-day-number { color: var(--text-secondary); font-size: 12px; }
.fc .fc-event { border-radius: 4px; font-size: 11px; }

/* ============================================
   AUTH PAGES
   ============================================ */

.auth-wrapper {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    background: var(--bg-primary);
}

.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-lg);
    padding: 40px;
}

.auth-brand {
    text-align: center;
    margin-bottom: 36px;
}

.auth-brand .logo {
    width: 48px;
    height: 48px;
    background: var(--accent);
    border-radius: var(--radius-md);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: #000;
    font-weight: 800;
    font-size: 22px;
    margin-bottom: 16px;
}

.auth-brand h2 {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.auth-brand p {
    font-size: 13px;
    color: var(--text-muted);
    margin-top: 6px;
}

.auth-footer {
    text-align: center;
    margin-top: 24px;
    font-size: 13px;
    color: var(--text-muted);
}

.auth-footer a {
    color: var(--accent);
    font-weight: 600;
}

/* ============================================
   AI PLAN
   ============================================ */

.ai-plan-output {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: 24px;
    margin-top: 24px;
}

.ai-plan-day {
    margin-bottom: 20px;
    padding-bottom: 20px;
    border-bottom: 1px solid var(--border-primary);
}

.ai-plan-day:last-child { border-bottom: none; }

.ai-plan-day .day-header {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.ai-plan-slot {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 10px 0;
    font-size: 13px;
}

.ai-plan-slot .slot-time {
    color: var(--text-muted);
    font-weight: 500;
    min-width: 100px;
    font-variant-numeric: tabular-nums;
}

.ai-plan-slot .slot-subject { font-weight: 600; }
.ai-plan-slot .slot-topic { color: var(--text-secondary); }

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

@keyframes slideIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(30px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

.skeleton {
    background: linear-gradient(90deg, var(--bg-card) 25%, var(--bg-card-hover) 50%, var(--bg-card) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s ease infinite;
    border-radius: var(--radius-sm);
}

/* ============================================
   RESPONSIVE (Mobile & Tablet)
   ============================================ */

/* Sidebar Backdrop */
.sidebar-backdrop {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.75);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 998;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.25s ease, visibility 0.25s ease;
}

.sidebar-backdrop.active {
    display: block;
    opacity: 1;
    visibility: visible;
}

/* Tablet (1024px and below) */
@media (max-width: 1024px) {
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 14px;
    }

    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Tablet & Large Mobile (768px and below) */
@media (max-width: 768px) {
    body.sidebar-opened {
        overflow: hidden;
    }

    .sidebar {
        position: fixed;
        top: 0;
        left: 0;
        height: 100vh;
        z-index: 999;
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
        box-shadow: 4px 0 24px rgba(0, 0, 0, 0.6);
        width: 260px;
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .main-content {
        margin-left: 0;
        width: 100%;
        min-width: 0;
    }

    .menu-toggle {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 38px;
        height: 38px;
        background: var(--bg-card);
        border: 1px solid var(--border-primary);
        border-radius: var(--radius-sm);
        color: var(--text-primary);
        font-size: 18px;
        cursor: pointer;
        transition: var(--transition);
    }

    .menu-toggle:hover {
        background: var(--bg-card-hover);
        border-color: var(--border-secondary);
    }

    .top-header {
        padding: 0 16px;
        height: 60px;
    }

    .page-title {
        font-size: 16px;
    }

    .page-content {
        padding: 16px 12px;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }

    .stat-card {
        padding: 16px;
    }

    .stat-value {
        font-size: 22px;
    }

    .stat-label {
        font-size: 11px;
    }

    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
        gap: 14px;
    }

    .timetable-grid {
        min-width: 680px;
    }

    .card {
        padding: 18px 16px;
    }

    .auth-card {
        padding: 28px 20px;
        margin: 16px;
    }

    .countdown-card .cd-value {
        font-size: 26px;
    }

    .countdown-card .cd-unit {
        min-width: 52px;
    }

    .otp-container {
        gap: 8px;
    }

    .otp-input {
        width: 44px;
        height: 52px;
        font-size: 22px;
    }

    .tabs {
        overflow-x: auto;
        white-space: nowrap;
        padding-bottom: 6px;
        -webkit-overflow-scrolling: touch;
    }

    .table-wrapper {
        border-radius: var(--radius-sm);
        -webkit-overflow-scrolling: touch;
    }

    table th,
    table td {
        padding: 10px 12px;
        font-size: 12px;
    }
}

/* Small Mobile (480px and below) */
@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }

    .top-header {
        padding: 0 12px;
    }

    #liveClock {
        font-size: 20px !important;
    }

    .countdown-card .cd-timer {
        gap: 6px;
    }

    .countdown-card .cd-unit {
        min-width: 44px;
        padding: 8px 4px;
    }

    .countdown-card .cd-value {
        font-size: 20px;
    }

    .countdown-card .cd-label {
        font-size: 9px;
    }

    .modal {
        width: 96%;
        margin: 10px;
        max-height: 92vh;
        padding: 0;
    }

    .modal-body {
        padding: 16px;
    }

    .modal-footer {
        padding: 12px 16px;
        flex-direction: column-reverse;
        gap: 8px;
    }

    .modal-footer .btn {
        width: 100%;
    }

    .task-item {
        padding: 12px;
        gap: 10px;
    }

    .task-meta {
        font-size: 11px;
        gap: 8px;
    }

    .otp-input {
        width: 38px;
        height: 48px;
        font-size: 18px;
    }
}

/* --- Utility Classes --- */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.gap-1 { gap: 8px; }
.gap-2 { gap: 16px; }
.d-flex { display: flex; }
.align-center { align-items: center; }
.justify-between { justify-content: space-between; }
.flex-wrap { flex-wrap: wrap; }
.w-100 { width: 100%; }
.hidden { display: none !important; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }

/* Activity Tracker Utilities */
.form-control-lg {
    padding: 12px 16px;
    font-size: 15px;
    border-radius: var(--radius-md);
}
.badge-dark {
    background: rgba(255,255,255,0.08);
    color: var(--text-secondary);
    border: 1px solid var(--border-primary);
}

@media (max-width: 640px) {
    .timeline-row {
        flex-direction: column;
        gap: 8px;
    }
    .timeline-time-col {
        width: 100%;
        text-align: left;
        display: flex;
        align-items: center;
        gap: 8px;
    }
    .timeline-node-col {
        display: none;
    }
}

/* ============================================
   25-MINUTE FOCUS ALARM & KNOWLEDGE BOOSTER
   ============================================ */

.focus-alarm-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 99999;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 16px;
}

.focus-alarm-card {
    background: #111111;
    border: 2px solid #ff4444;
    box-shadow: 0 0 40px rgba(255, 68, 68, 0.35), 0 20px 60px rgba(0, 0, 0, 0.9);
    border-radius: var(--radius-lg);
    width: 100%;
    max-width: 680px;
    padding: 28px;
    position: relative;
    overflow: hidden;
    animation: alarmPulseBorder 2s infinite ease-in-out;
}

@keyframes alarmPulseBorder {
    0%, 100% { border-color: #ff4444; box-shadow: 0 0 25px rgba(255, 68, 68, 0.3); }
    50% { border-color: #ffaa00; box-shadow: 0 0 40px rgba(255, 170, 0, 0.45); }
}

.alarm-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    padding-bottom: 16px;
    margin-bottom: 18px;
}

.alarm-bell-icon {
    font-size: 32px;
    display: inline-block;
    animation: bellRing 0.8s infinite ease-in-out;
}

@keyframes bellRing {
    0%, 100% { transform: rotate(0); }
    15% { transform: rotate(-18deg); }
    30% { transform: rotate(18deg); }
    45% { transform: rotate(-12deg); }
    60% { transform: rotate(12deg); }
    75% { transform: rotate(-6deg); }
    90% { transform: rotate(6deg); }
}

.alarm-badge {
    display: inline-block;
    font-size: 11px;
    font-weight: 800;
    color: #ff4444;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.alarm-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
    margin-top: 2px;
}

.fact-meta-bar {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 12px;
}

.fact-topic-name {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
}

.target-text-box {
    background: #080808;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: 16px 18px;
    font-size: 15px;
    line-height: 1.7;
    font-family: 'Inter', sans-serif;
    color: #777777;
    max-height: 160px;
    overflow-y: auto;
    user-select: none;
    letter-spacing: 0.2px;
}

.target-text-box .char-untyped {
    color: #666666;
}

.target-text-box .char-correct {
    color: #44ff44;
    background: rgba(68, 255, 68, 0.12);
    border-radius: 2px;
}

.target-text-box .char-incorrect {
    color: #ffffff;
    background: #ff4444;
    border-radius: 2px;
    text-decoration: underline;
}

.target-text-box .char-cursor {
    color: #ffffff;
    border-left: 2px solid #4488ff;
    animation: cursorBlink 1s infinite;
}

@keyframes cursorBlink {
    0%, 100% { border-color: #4488ff; }
    50% { border-color: transparent; }
}

.typing-input-field {
    width: 100%;
    background: #0a0a0a;
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-size: 14px;
    line-height: 1.5;
    padding: 14px;
    outline: none;
    font-family: 'Inter', sans-serif;
    resize: none;
    transition: var(--transition);
}

.typing-input-field:focus {
    border-color: #4488ff;
    box-shadow: 0 0 15px rgba(68, 136, 255, 0.25);
}

.typing-metrics-bar {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-top: 14px;
    background: rgba(255, 255, 255, 0.03);
    padding: 10px 16px;
    border-radius: var(--radius-md);
    border: 1px solid rgba(255, 255, 255, 0.06);
}

.metric-item {
    display: flex;
    flex-direction: column;
}

.metric-val {
    font-size: 16px;
    font-weight: 800;
    color: var(--text-primary);
    font-family: monospace;
}

.metric-lbl {
    font-size: 10px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.typing-progress-track {
    width: 100%;
    height: 8px;
    background: #222222;
    border-radius: 4px;
    overflow: hidden;
}

.typing-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #4488ff, #44ff44);
    transition: width 0.15s ease-out;
}

.confetti-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    overflow: hidden;
    z-index: 10;
}

.confetti-piece {
    position: absolute;
    width: 8px;
    height: 12px;
    top: -20px;
    opacity: 0.9;
    animation: confettiFall 2.5s forwards ease-in-out;
}

@keyframes confettiFall {
    0% { transform: translateY(0) rotate(0); opacity: 1; }
    100% { transform: translateY(500px) rotate(720deg); opacity: 0; }
}


/* ============================================
   EXAM MODULE STYLES
   ============================================ */

/* --- Exam Cards Grid --- */
.exam-cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 16px;
}

.exam-card {
    background: var(--bg-card);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    padding: 20px;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.exam-card:hover {
    border-color: var(--border-secondary);
    background: var(--bg-card-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.exam-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.exam-subject {
    font-size: 15px;
    font-weight: 700;
    flex: 1;
}

.exam-shift-badge {
    font-size: 11px;
    padding: 3px 10px;
    border-radius: 20px;
    background: var(--border-secondary);
    color: var(--text-secondary);
    font-weight: 600;
    white-space: nowrap;
}

.exam-card-meta {
    display: flex;
    gap: 16px;
    font-size: 12px;
    color: var(--text-muted);
    flex-wrap: wrap;
}

.exam-card-session {
    font-size: 12px;
    color: var(--text-secondary);
}

.exam-card-stats {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.exam-card-actions {
    display: flex;
    gap: 8px;
    margin-top: 4px;
}

/* --- Exam Instructions Page --- */
.exam-instructions-wrapper {
    max-width: 800px;
}

.exam-detail-card {
    padding: 24px;
}

.exam-detail-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 24px;
}

.exam-detail-icon {
    width: 48px;
    height: 48px;
    background: var(--border-secondary);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    flex-shrink: 0;
}

.exam-info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 12px;
}

.exam-info-item {
    background: var(--bg-input);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
}

.exam-info-label {
    font-size: 11px;
    color: var(--text-muted);
    display: block;
    margin-bottom: 4px;
}

.exam-info-value {
    font-size: 15px;
    font-weight: 700;
}

.exam-instructions-list {
    padding-left: 20px;
}

.exam-instructions-list li {
    margin-bottom: 16px;
    color: var(--text-secondary);
    font-size: 13px;
}

.question-legend-grid {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 16px 0 16px 8px;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 13px;
}

.legend-dot {
    width: 24px;
    height: 24px;
    border-radius: 6px;
    flex-shrink: 0;
}

.legend-not-visited { background: #374151; border: 1px solid #4b5563; }
.legend-not-answered { background: #ef4444; }
.legend-answered { background: #22c55e; }
.legend-marked { background: #a855f7; }
.legend-marked-answered { background: #a855f7; border: 2px solid #22c55e; }

/* --- Result Page --- */
.result-score-card {
    padding: 24px;
}

.result-score-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: 24px;
    gap: 16px;
    flex-wrap: wrap;
}

.result-score-grid {
    display: flex;
    align-items: center;
    gap: 40px;
    flex-wrap: wrap;
}

.result-score-main {
    text-align: center;
}

.result-score-circle {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(
        var(--success) calc(var(--percent) * 3.6deg),
        var(--border-secondary) calc(var(--percent) * 3.6deg)
    );
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    position: relative;
    margin: 0 auto 8px;
}

.result-score-circle::before {
    content: '';
    position: absolute;
    inset: 8px;
    background: var(--bg-card);
    border-radius: 50%;
}

.result-score-value {
    font-size: 28px;
    font-weight: 800;
    position: relative;
    z-index: 1;
}

.result-score-max {
    font-size: 12px;
    color: var(--text-muted);
    position: relative;
    z-index: 1;
}

.result-score-percent {
    font-size: 14px;
    font-weight: 700;
    color: var(--success);
}

.result-stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    flex: 1;
    min-width: 240px;
}

.result-stat {
    background: var(--bg-input);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-sm);
    padding: 16px;
    text-align: center;
}

.result-stat-value {
    font-size: 24px;
    font-weight: 800;
}

.result-stat-label {
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 4px;
}

/* --- Question Review Cards --- */
.result-question-card {
    padding: 20px;
    margin-bottom: 16px;
    border-left: 3px solid var(--border-secondary);
}

.result-question-card.result-q-correct {
    border-left-color: var(--success);
}

.result-question-card.result-q-wrong {
    border-left-color: var(--danger);
}

.result-question-card.result-q-skipped {
    border-left-color: var(--text-muted);
}

.result-q-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 12px;
}

.result-q-num {
    font-size: 15px;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 8px;
}

.result-q-text {
    font-size: 14px;
    line-height: 1.7;
    margin-bottom: 16px;
    color: var(--text-secondary);
}

.result-q-options {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 16px;
}

.result-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 14px;
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-sm);
    font-size: 13px;
    background: var(--bg-input);
}

.result-option.result-opt-correct {
    background: rgba(68, 255, 68, 0.06);
    border-color: rgba(68, 255, 68, 0.3);
}

.result-option.result-opt-wrong {
    background: rgba(255, 68, 68, 0.06);
    border-color: rgba(255, 68, 68, 0.3);
}

.result-opt-label {
    font-weight: 700;
    color: var(--text-muted);
    width: 30px;
    flex-shrink: 0;
}

.result-opt-text {
    flex: 1;
}

.result-opt-badge {
    font-size: 11px;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: 10px;
    white-space: nowrap;
}

.result-opt-badge.correct {
    background: var(--success-soft);
    color: var(--success);
}

.result-opt-badge.wrong {
    background: var(--danger-soft);
    color: var(--danger);
}

.result-solution {
    margin-top: 8px;
}

.result-solution summary {
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    color: var(--info);
    padding: 8px 0;
    user-select: none;
}

.result-solution summary:hover {
    color: var(--accent);
}

.result-solution-text {
    padding: 16px;
    background: rgba(68, 136, 255, 0.05);
    border: 1px solid rgba(68, 136, 255, 0.15);
    border-radius: var(--radius-sm);
    font-size: 13px;
    line-height: 1.7;
    color: var(--text-secondary);
    margin-top: 8px;
}

/* --- Admin Upload Dropzone --- */
.exam-upload-dropzone {
    border: 2px dashed var(--border-secondary);
    border-radius: var(--radius-md);
    padding: 40px 20px;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
}

.exam-upload-dropzone:hover {
    border-color: var(--text-muted);
    background: rgba(255,255,255,0.02);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .exam-cards-grid {
        grid-template-columns: 1fr;
    }

    .exam-info-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .result-score-grid {
        flex-direction: column;
        align-items: stretch;
    }

    .result-stats-grid {
        min-width: auto;
    }
}