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

:root {
    --primary: #4f46e5;
    /* Vibrant Indigo */
    --primary-hover: #4338ca;
    --primary-light: #e0e7ff;

    --secondary: #10b981;
    /* Emerald */
    --secondary-hover: #059669;

    --warning: #f59e0b;
    /* Amber */
    --danger: #ef4444;
    /* Red */
    --danger-hover: #dc2626;

    --bg: #f8fafc;
    /* Slate 50 */
    --surface: #ffffff;
    --surface-hover: #f1f5f9;

    --text: #0f172a;
    /* Slate 900 */
    --text-muted: #64748b;
    /* Slate 500 */

    --border: #e2e8f0;
    /* Slate 200 */

    --radius: 0.75rem;
    /* 12px for softer, modern corners */
    --radius-sm: 0.5rem;

    /* Premium soft layered shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.05), 0 2px 4px -2px rgb(0 0 0 / 0.05);
    --shadow-md: 0 10px 15px -3px rgb(0 0 0 / 0.05), 0 4px 6px -4px rgb(0 0 0 / 0.05);
    --shadow-lg: 0 20px 25px -5px rgb(0 0 0 / 0.05), 0 8px 10px -6px rgb(0 0 0 / 0.05);

    /* Glassmorphism backgrounds */
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.5);
}

[data-theme="dark"] {
    --primary: #6366f1;
    /* Lighter Indigo for dark mode visibility */
    --primary-hover: #818cf8;
    --primary-light: rgba(99, 102, 241, 0.2);

    --bg: #0f172a;
    /* Deep Slate 900 */
    --surface: #1e293b;
    /* Slate 800 */
    --surface-hover: #334155;

    --text: #f8fafc;
    /* Slate 50 */
    --text-muted: #94a3b8;
    /* Slate 400 */

    --border: #334155;
    /* Slate 700 */

    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.5);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.3), 0 2px 4px -2px rgb(0 0 0 / 0.3);
    --shadow-md: 0 10px 15px -3px rgb(0 0 0 / 0.4), 0 4px 6px -4px rgb(0 0 0 / 0.4);
    --shadow-lg: 0 20px 25px -5px rgb(0 0 0 / 0.5), 0 8px 10px -6px rgb(0 0 0 / 0.5);

    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.05);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', system-ui, -apple-system, blinkmacsystemfont, 'Segoe UI', roboto, sans-serif;
}

body {
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
    width: 100%;
    flex: 1;
}

/* Glassmorphism Navigation */
.nav {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-sm);
    border-bottom: 1px solid var(--glass-border);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all 0.3s ease;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--text);
    letter-spacing: -0.025em;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* Layout Utilities */

.auth-container {
    max-width: 450px;
    margin: 4rem auto;
}

/* Exam Dashboard Cards */
.exam-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}

.exam-card {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
}

.exam-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--primary);
    transform: scaleY(0);
    transition: transform 0.3s ease;
    transform-origin: bottom;
}

.exam-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.exam-card:hover::before {
    transform: scaleY(1);
    transform-origin: top;
}

.exam-meta-box {
    background: var(--bg);
    padding: 0.75rem;
    border-radius: var(--radius-sm);
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border);
}

.card {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 2rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.flex {
    display: flex;
    gap: 1rem;
}

.flex-col {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.grid {
    display: grid;
    gap: 1rem;
}

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

/* Make grid responsive on mobile */
@media (max-width: 768px) {
    .grid-cols-2 {
        grid-template-columns: 1fr;
    }
}

.justify-between {
    justify-content: space-between;
}

.justify-center {
    justify-content: center;
}

.justify-end {
    justify-content: flex-end;
}

.items-center {
    align-items: center;
}

.text-center {
    text-align: center;
}

.mt-4 {
    margin-top: 1rem;
}

.mb-4 {
    margin-bottom: 1rem;
}

.p-4 {
    padding: 1rem;
}

/* Components */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    background: var(--primary);
    color: white;
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-sm);
    border: none;
    cursor: pointer;
    font-weight: 500;
    font-size: 0.95rem;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: var(--shadow-sm);
}

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

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: white !important;
    box-shadow: 0 4px 6px -1px rgba(79, 70, 229, 0.2), 0 2px 4px -1px rgba(79, 70, 229, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.btn-primary:hover {
    box-shadow: 0 10px 15px -3px rgba(79, 70, 229, 0.3), 0 4px 6px -2px rgba(79, 70, 229, 0.15);
    transform: translateY(-2px);
    background: linear-gradient(135deg, var(--primary-hover) 0%, var(--primary) 100%);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-danger {
    background-color: var(--danger);
    color: white;
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-secondary {
    background-color: var(--surface);
    color: var(--text);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background-color: var(--background);
}

/* Avatars */
.avatar {
    width: 2.5rem;
    height: 2.5rem;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: white;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.85rem;
    margin-right: 0.75rem;
    box-shadow: 0 2px 4px rgba(79, 70, 229, 0.2);
}

.student-cell {
    display: flex;
    align-items: center;
}

/* Tooltips */
.tooltip {
    position: relative;
}

.tooltip:before {
    content: attr(data-tip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    padding: 0.4rem 0.6rem;
    background: rgba(15, 23, 42, 0.9);
    color: white;
    font-size: 0.75rem;
    border-radius: 0.25rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s;
    pointer-events: none;
    margin-bottom: 5px;
}

.tooltip:hover:before {
    opacity: 1;
    visibility: visible;
    bottom: 110%;
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
}

.btn-sm {
    padding: 0.4rem 0.8rem;
    font-size: 0.85rem;
}

.btn-icon {
    padding: 0.5rem;
    width: 2.2rem;
    height: 2.2rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.2s;
}

.btn-ghost {
    background: transparent;
    color: var(--text-muted);
    box-shadow: none;
    border: 1px solid transparent;
}

.btn-ghost:hover {
    background: #f1f5f9;
    color: var(--primary);
}

.btn-ghost.text-warning:hover {
    color: var(--warning);
    background: #fffbeb;
}

.btn-ghost.text-danger:hover {
    color: var(--danger);
    background: #fef2f2;
}

.btn-ghost.text-primary:hover {
    color: var(--primary);
    background: #e0e7ff;
}

input:not([type="checkbox"]):not([type="radio"]):not([type="color"]),
select,
textarea {
    width: 100%;
    padding: 0.875rem;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-size: 1rem;
    transition: border-color 0.2s;
    background: var(--background);
    color: var(--text);
}

input:not([type="checkbox"]):not([type="radio"]):not([type="color"]):focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

input[type="checkbox"],
input[type="radio"] {
    width: 1.1rem;
    height: 1.1rem;
    accent-color: var(--primary);
    cursor: pointer;
    margin: 0;
}

.form-group {
    margin-bottom: 1rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text);
}

.alert {
    padding: 1rem;
    border-radius: var(--radius);
    margin-bottom: 1rem;
    display: none;
    /* Hidden by default */
}

.alert-success {
    background-color: #dcfce7;
    color: #166534;
    border: 1px solid #bbf7d0;
}

.alert-error {
    background-color: #fee2e2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

/* Navbar */
.navbar {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
}

.navbar .container {
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    font-weight: 800;
    font-size: 1.5rem;
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 1.5rem;
}

/* Exam Dashboard Specifics */
.exam-list {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.exam-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    transition: transform 0.2s, box-shadow 0.2s;
}

.exam-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.exam-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.badge {
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    background: var(--border);
}

.badge-blue {
    background: #e0e7ff;
    color: #3730a3;
}

.badge-green {
    background: #dcfce7;
    color: #166534;
}

.badge-yellow {
    background: #fef3c7;
    color: #b45309;
}

/* Exam Taking Interface */
.exam-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 2rem;
    align-items: start;
}

.sidebar {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 1.5rem;
    position: sticky;
    top: 2rem;
    border: 1px solid var(--border);
}

.question-nav {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
    margin-top: 1rem;
}

.q-nav-btn {
    width: 100%;
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 0.5rem;
    background: var(--border);
    cursor: pointer;
    font-weight: 600;
    font-size: 0.875rem;
    border: 2px solid transparent;
}

.q-nav-btn.active {
    border-color: var(--primary);
    background: #e0e7ff;
    color: var(--primary);
}

.q-nav-btn.answered {
    background: var(--success);
    color: white;
}

.q-nav-btn.review {
    background: var(--warning);
    color: white;
}

.timer-box {
    text-align: center;
    margin-bottom: 1.5rem;
    padding: 1rem;
    background: #e0e7ff;
    border-radius: var(--radius);
    color: var(--primary);
    font-weight: 700;
    font-size: 1.5rem;
    font-variant-numeric: tabular-nums;
}

.question-area {
    background: var(--surface);
    padding: 2.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    min-height: 500px;
}

.question-text {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 2rem;
}

.options-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.option-label {
    display: flex;
    align-items: center;
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s;
}

.option-label:hover {
    border-color: var(--primary);
    background: #f8fafc;
}

.option-label input {
    width: 1.25rem;
    height: 1.25rem;
    margin-right: 1rem;
}

.option-label.selected {
    border-color: var(--primary);
    background: #e0e7ff;
}

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

    .sidebar {
        position: static;
        margin-bottom: 2rem;
    }
}

/* Toggle Switch */
.toggle-switch {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    cursor: pointer;
    margin-top: 0;
}

.toggle-input {
    display: none;
}

.toggle-slider {
    position: relative;
    width: 3rem;
    height: 1.6rem;
    background-color: var(--border);
    border-radius: 999px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    flex-shrink: 0;
}

.toggle-slider:before {
    content: "";
    position: absolute;
    height: 1.2rem;
    width: 1.2rem;
    left: 0.2rem;
    bottom: 0.2rem;
    background-color: white;
    border-radius: 50%;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.toggle-input:checked+.toggle-slider {
    background-color: var(--primary);
}

.toggle-input:checked+.toggle-slider:before {
    transform: translateX(1.4rem);
}

.toggle-label {
    font-weight: 500;
    color: var(--text);
    user-select: none;
    font-size: 0.95rem;
}

/* Custom Table Styles */
.table-container {
    overflow-x: auto;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    margin-top: 1rem;
    background: var(--surface);
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

.custom-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    min-width: 600px;
}

.custom-table thead {
    background-color: var(--primary);
    color: white;
}

.custom-table th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    font-size: 0.875rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    border-bottom: 2px solid rgba(255, 255, 255, 0.1);
}

.custom-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border);
    color: var(--text);
    font-size: 0.95rem;
    vertical-align: middle;
}

.custom-table tbody tr:last-child td {
    border-bottom: none;
}

.custom-table tbody tr:hover {
    background-color: #f1f5f9;
}

/* Zebra striping for readability */
.custom-table tbody tr:nth-child(even) {
    background-color: #f8fafc;
}

.custom-table td .badge {
    box-shadow: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
}

/* --- Dashboard Specific Styles --- */
.dashboard-tabs {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    padding: 0.5rem;
    background: var(--surface);
    border-radius: var(--radius);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--border);
    flex-wrap: wrap;
}

.tab-btn {
    padding: 0.75rem 1.5rem;
    border-radius: calc(var(--radius) - 2px);
    font-weight: 600;
    color: var(--text-muted);
    background: transparent;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.tab-btn:hover {
    color: var(--primary);
    background: rgba(99, 102, 241, 0.05);
}

.tab-btn.active {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 6px -1px rgba(99, 102, 241, 0.3);
}

.form-section-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.02);
}

.exam-meta-box {
    display: flex;
    flex-direction: column;
    padding: 0.5rem;
    background-color: var(--background);
    border: 1px solid var(--border);
    border-radius: var(--radius);
}

[data-theme='dark'] .exam-meta-box {
    background-color: rgba(255, 255, 255, 0.03);
    border-color: rgba(255, 255, 255, 0.08);
}

.form-section-card h3 {
    margin-top: 0;
    margin-bottom: 1rem;
    font-size: 1.1rem;
    color: var(--primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    border-bottom: 1px solid var(--border);
    padding-bottom: 0.5rem;
}

.exam-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}

/* --- Missing Layout Utilities --- */
.w-16 {
    width: max-content;
}

/* Base Table Styling */
.table-responsive {
    width: 100%;
    overflow-x: auto;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    box-shadow: var(--shadow-sm);
    background: var(--surface);
}

table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.95rem;
}

table th {
    background-color: var(--surface-hover);
    color: var(--text-muted);
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
    padding: 1rem 1.5rem;
    border-bottom: 2px solid var(--border);
}

table td {
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border);
    color: var(--text);
    vertical-align: middle;
}

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

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

[data-theme="dark"] table tr:hover td {
    background-color: var(--surface-hover);
}

/* --- Student Live Exam (Zen Mode) --- */
.exam-layout {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: 2rem;
    align-items: start;
}

@media (max-width: 900px) {
    .exam-layout {
        grid-template-columns: 1fr;
    }
}

.sidebar {
    background: var(--surface);
    padding: 1.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    position: sticky;
    top: 5rem;
    /* Stays visible under the glass nav */
}

.timer-box {
    background: linear-gradient(135deg, var(--bg) 0%, var(--surface-hover) 100%);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 1rem;
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 1.5rem;
    font-variant-numeric: tabular-nums;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.02);
}

.timer-box.warning {
    color: var(--danger);
    background: rgba(239, 68, 68, 0.1);
    border-color: rgba(239, 68, 68, 0.3);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0% {
        opacity: 1;
    }

    50% {
        opacity: 0.7;
    }

    100% {
        opacity: 1;
    }
}

.question-nav {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(40px, 1fr));
    gap: 0.5rem;
}

.nav-btn {
    aspect-ratio: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    transition: all 0.2s;
}

.nav-btn:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-sm);
}

.nav-btn.answered {
    background: var(--secondary);
    color: white;
    border-color: var(--secondary);
}

.nav-btn.review {
    background: var(--warning);
    color: white;
    border-color: var(--warning);
}

.nav-btn.active {
    box-shadow: 0 0 0 3px var(--primary-light);
    border-color: var(--primary);
}

.question-area {
    background: var(--surface);
    padding: 2.5rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
    animation: slideIn 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.question-text {
    font-size: 1.15rem;
    font-weight: 500;
    margin-bottom: 2rem;
    line-height: 1.6;
}

.options-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.h-16 {
    height: 4rem;
}

.w-full {
    width: 100%;
}

.max-w-4xl {
    max-width: 56rem;
}

.max-w-2xl {
    max-width: 42rem;
}

.text-5xl {
    font-size: 3rem;
    line-height: 1;
}

.text-3xl {
    font-size: 1.875rem;
    line-height: 2.25rem;
}

.text-xl {
    font-size: 1.25rem;
    line-height: 1.75rem;
}

.text-lg {
    font-size: 1.125rem;
    line-height: 1.75rem;
}

.text-sm {
    font-size: 0.875rem;
    line-height: 1.25rem;
}

.text-xs {
    font-size: 0.75rem;
    line-height: 1rem;
}

.font-bold {
    font-weight: 700;
}

.font-medium {
    font-weight: 500;
}

.rounded-full {
    border-radius: 9999px;
}

.mx-auto {
    margin-left: auto;
    margin-right: auto;
}

.mb-2 {
    margin-bottom: 0.5rem;
}

.mb-6 {
    margin-bottom: 1.5rem;
}

.mb-12 {
    margin-bottom: 3rem;
}

.mt-2 {
    margin-top: 0.5rem;
}

.mt-16 {
    margin-top: 4rem;
}

.py-12 {
    padding-top: 3rem;
    padding-bottom: 3rem;
}

.py-8 {
    padding-top: 2rem;
    padding-bottom: 2rem;
}

.p-6 {
    padding: 1.5rem;
}

.p-8 {
    padding: 2rem;
}

.gap-8 {
    gap: 2rem;
}

.grid-cols-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.block {
    display: block;
}

/* Dark Mode Variables and Overrides - Enhanced */
[data-theme='dark'] {
    --primary: #6366f1;
    /* Rich indigo */
    --primary-hover: #4f46e5;
    --secondary: #a1a1aa;
    --success: #22c55e;
    --danger: #ef4444;
    --warning: #f59e0b;

    --background: #09090b;
    /* Deep zinc-950 */
    --surface: #18181b;
    /* Zinc-900 */
    --border: #27272a;
    /* Zinc-800 */

    --text: #fafafa;
    /* Zinc-50 */
    --text-muted: #a1a1aa;
    /* Zinc-400 */
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.8), 0 2px 4px -2px rgba(0, 0, 0, 0.8);
}

/* Glassmorphism & Slick Surfaces */
[data-theme='dark'] .card,
[data-theme='dark'] .sidebar,
[data-theme='dark'] .question-area,
[data-theme='dark'] .navbar {
    background: rgba(24, 24, 27, 0.75);
    /* Translucent surface */
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.08);
    /* Subtle glow */
}

/* Better inputs */
[data-theme='dark'] input,
[data-theme='dark'] select,
[data-theme='dark'] textarea {
    background-color: rgba(9, 9, 11, 0.8);
    border-color: var(--border);
    color: var(--text);
}

[data-theme='dark'] input:focus,
[data-theme='dark'] select:focus,
[data-theme='dark'] textarea:focus {
    background-color: #18181b;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

/* Base resets & utilities overrides */
[data-theme='dark'] .bg-gray-50,
[data-theme='dark'] body {
    background-color: var(--background) !important;
    color: var(--text) !important;
}

[data-theme='dark'] .bg-white {
    background-color: var(--surface) !important;
    color: var(--text) !important;
}

[data-theme='dark'] .text-slate-900 {
    color: #f4f4f5 !important;
}

[data-theme='dark'] h1,
[data-theme='dark'] h2,
[data-theme='dark'] h3,
[data-theme='dark'] h4 {
    color: #f4f4f5;
}

/* Enhanced Gradient Buttons */
[data-theme='dark'] .btn-primary {
    background: linear-gradient(135deg, #6366f1 0%, #4f46e5 100%);
    box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.39);
}

[data-theme='dark'] .btn-primary:hover {
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

[data-theme='dark'] .dashboard-tabs,
[data-theme='dark'] .form-section-card {
    background: rgba(24, 24, 27, 0.75);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-color: rgba(255, 255, 255, 0.08);
}

[data-theme='dark'] .tab-btn.active {
    box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.39);
}

[data-theme='dark'] .alert-success {
    background-color: rgba(34, 197, 94, 0.15);
    color: #4ade80;
    border-color: rgba(34, 197, 94, 0.2);
}

[data-theme='dark'] .alert-error {
    background-color: rgba(239, 68, 68, 0.15);
    color: #f87171;
    border-color: rgba(239, 68, 68, 0.2);
}

[data-theme='dark'] .btn-ghost:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text);
    border: 1px solid transparent;
}

[data-theme='dark'] .btn-ghost.text-warning:hover {
    background: rgba(245, 158, 11, 0.15);
    color: #fbbf24;
}

[data-theme='dark'] .btn-ghost.text-danger:hover {
    background: rgba(239, 68, 68, 0.15);
    color: #f87171;
}

[data-theme='dark'] .btn-ghost.text-primary:hover {
    background: rgba(99, 102, 241, 0.15);
    color: #818cf8;
}

[data-theme='dark'] .badge-blue {
    background: rgba(99, 102, 241, 0.2);
    color: #a5b4fc;
    border: 1px solid rgba(99, 102, 241, 0.3);
}

[data-theme='dark'] .badge-green {
    background: rgba(34, 197, 94, 0.2);
    color: #86efac;
    border: 1px solid rgba(34, 197, 94, 0.3);
}

[data-theme='dark'] .badge-yellow {
    background: rgba(245, 158, 11, 0.2);
    color: #fcd34d;
    border: 1px solid rgba(245, 158, 11, 0.3);
}

[data-theme='dark'] .timer-box {
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.3);
    color: #a5b4fc;
}

[data-theme='dark'] .q-nav-btn {
    background: var(--surface);
    border-color: var(--border);
    color: var(--text);
}

[data-theme='dark'] .q-nav-btn:hover {
    background: rgba(255, 255, 255, 0.05);
}

[data-theme='dark'] .q-nav-btn.active {
    background: rgba(99, 102, 241, 0.2);
    border-color: #6366f1;
    color: #a5b4fc;
}

[data-theme='dark'] .q-nav-btn.answered {
    background: var(--success);
    color: #000;
    border-color: var(--success);
}

[data-theme='dark'] .q-nav-btn.review {
    background: var(--warning);
    color: #000;
    border-color: var(--warning);
}

[data-theme='dark'] .option-label:hover {
    background: rgba(255, 255, 255, 0.02);
    border-color: #52525b;
}

[data-theme='dark'] .option-label.selected {
    background: rgba(99, 102, 241, 0.1);
    border-color: #6366f1;
}

[data-theme='dark'] .custom-table tbody tr:hover {
    background-color: rgba(255, 255, 255, 0.04);
}

[data-theme='dark'] .custom-table tbody tr:nth-child(even) {
    background-color: rgba(255, 255, 255, 0.01);
}

[data-theme='dark'] .custom-table th {
    background-color: #18181b;
    border-bottom: 2px solid #27272a;
}

/* Elegant index.html card icons */
[data-theme='dark'] .bg-indigo-100 {
    background-color: rgba(99, 102, 241, 0.2) !important;
    border: 1px solid rgba(99, 102, 241, 0.3);
}

[data-theme='dark'] .bg-emerald-100 {
    background-color: rgba(16, 185, 129, 0.2) !important;
    border: 1px solid rgba(16, 185, 129, 0.3);
}

[data-theme='dark'] .text-indigo-600 {
    color: #818cf8 !important;
}

[data-theme='dark'] .text-emerald-600 {
    color: #34d399 !important;
}

[data-theme='dark'] .border-t {
    border-color: var(--border) !important;
}

[data-theme='dark'] .hover\:border-indigo-500:hover {
    border-color: #6366f1 !important;
}

/* --- Teacher Specific Theme Overrides --- */
.theme-teacher .btn-primary,
.btn-primary.theme-teacher,
.theme-teacher .tab-btn.active,
.tab-btn.active.theme-teacher,
.theme-teacher .toggle-input:checked+.toggle-slider,
.toggle-input.theme-teacher:checked+.toggle-slider {
    --primary: #10b981;
    /* Emerald 500 */
    --primary-hover: #059669;
    /* Emerald 600 */
}

/* Dark Mode Teacher Overrides */
[data-theme='dark'] .theme-teacher .btn-primary,
[data-theme='dark'] .btn-primary.theme-teacher,
[data-theme='dark'] .theme-teacher .tab-btn.active,
[data-theme='dark'] .tab-btn.active.theme-teacher,
[data-theme='dark'] .theme-teacher .toggle-input:checked+.toggle-slider,
[data-theme='dark'] .toggle-input.theme-teacher:checked+.toggle-slider {
    --primary: #34d399;
    /* Emerald 400 */
    --primary-hover: #10b981;
    /* Emerald 500 */
}

/* Override primary button gradient for teacher theme in dark mode */
[data-theme='dark'] .theme-teacher .btn-primary,
[data-theme='dark'] .btn-primary.theme-teacher {
    background: linear-gradient(135deg, #34d399 0%, #10b981 100%);
    box-shadow: 0 4px 14px 0 rgba(16, 185, 129, 0.39);
}

[data-theme='dark'] .theme-teacher .btn-primary:hover,
[data-theme='dark'] .btn-primary.theme-teacher:hover {
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.5);
}

[data-theme='dark'] .theme-teacher .tab-btn.active,
[data-theme='dark'] .tab-btn.active.theme-teacher {
    box-shadow: 0 4px 14px 0 rgba(16, 185, 129, 0.39);
}

/* --- Student Specific Theme Overrides --- */
.theme-student .btn-primary,
.btn-primary.theme-student,
.theme-student .tab-btn.active,
.tab-btn.active.theme-student,
.theme-student .toggle-input:checked+.toggle-slider,
.toggle-input.theme-student:checked+.toggle-slider {
    --primary: #8b5cf6;
    /* Violet 500 */
    --primary-hover: #7c3aed;
    /* Violet 600 */
}

/* Dark Mode Student Overrides */
[data-theme='dark'] .theme-student .btn-primary,
[data-theme='dark'] .btn-primary.theme-student,
[data-theme='dark'] .theme-student .tab-btn.active,
[data-theme='dark'] .tab-btn.active.theme-student,
[data-theme='dark'] .theme-student .toggle-input:checked+.toggle-slider,
[data-theme='dark'] .toggle-input.theme-student:checked+.toggle-slider {
    --primary: #a78bfa;
    /* Violet 400 */
    --primary-hover: #8b5cf6;
    /* Violet 500 */
}

/* Override primary button gradient for student theme in dark mode */
[data-theme='dark'] .theme-student .btn-primary,
[data-theme='dark'] .btn-primary.theme-student {
    background: linear-gradient(135deg, #a78bfa 0%, #8b5cf6 100%);
    box-shadow: 0 4px 14px 0 rgba(139, 92, 246, 0.39);
}

/* Student Assignment Checklist */
.student-assign-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 0.75rem;
    border-radius: var(--radius);
    transition: background 0.2s;
    margin-bottom: 0.25rem;
}

.student-assign-row:hover {
    background: rgba(0, 0, 0, 0.03);
}

[data-theme='dark'] .student-assign-row:hover {
    background: rgba(255, 255, 255, 0.05);
}

.student-assign-row label {
    display: flex;
    flex-direction: column;
    cursor: pointer;
    flex: 1;
}

.student-assign-row .student-name {
    font-weight: 500;
    font-size: 0.95rem;
}

.student-assign-row .student-detail {
    font-size: 0.8rem;
    color: var(--text-muted);
}

[data-theme='dark'] .theme-student .btn-primary:hover,
[data-theme='dark'] .btn-primary.theme-student:hover {
    box-shadow: 0 6px 20px rgba(139, 92, 246, 0.5);
}

[data-theme='dark'] .theme-student .tab-btn.active,
[data-theme='dark'] .tab-btn.active.theme-student {
    box-shadow: 0 4px 14px 0 rgba(139, 92, 246, 0.39);
}