:root {
    --bg: #eef2f8;
    --bg-accent: radial-gradient(circle at top left, rgba(82, 96, 255, 0.16), transparent 32%),
        radial-gradient(circle at top right, rgba(34, 197, 94, 0.14), transparent 24%),
        linear-gradient(180deg, #f6f8fc 0%, #edf2f9 100%);
    --surface: rgba(255, 255, 255, 0.88);
    --surface-strong: #ffffff;
    --surface-soft: #f4f7fb;
    --border: rgba(136, 149, 173, 0.18);
    --border-strong: rgba(102, 115, 146, 0.22);
    --text: #19233a;
    --muted: #73809b;
    --primary: #4154ff;
    --primary-dark: #2738d8;
    --primary-soft: rgba(65, 84, 255, 0.10);
    --success: #14b86a;
    --success-soft: rgba(20, 184, 106, 0.13);
    --danger: #ef4444;
    --danger-soft: rgba(239, 68, 68, 0.12);
    --warning: #f59e0b;
    --warning-soft: rgba(245, 158, 11, 0.13);
    --shadow-lg: 0 30px 70px rgba(31, 45, 85, 0.14);
    --shadow-md: 0 18px 40px rgba(31, 45, 85, 0.10);
    --shadow-sm: 0 10px 22px rgba(31, 45, 85, 0.08);
    --radius-xl: 28px;
    --radius-lg: 22px;
    --radius-md: 16px;
    --radius-sm: 12px;
    --font: "Inter", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: var(--font);
    color: var(--text);
    background: var(--bg-accent);
}

body.auth-body {
    display: grid;
    place-items: center;
    padding: 28px 16px;
}

a {
    color: inherit;
}

button,
input,
select {
    font: inherit;
}

.app-shell {
    width: min(1240px, calc(100% - 32px));
    margin: 26px auto 48px;
}

.topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
    padding: 18px 22px;
    margin-bottom: 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    background: rgba(255, 255, 255, 0.72);
    box-shadow: var(--shadow-sm);
    backdrop-filter: blur(18px);
}

.brand {
    display: flex;
    align-items: center;
    gap: 14px;
}

.brand-mark,
.brand-avatar {
    width: 52px;
    height: 52px;
    display: grid;
    place-items: center;
    border-radius: 18px;
    background: linear-gradient(145deg, #ffffff, #e6ebf5);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.9), var(--shadow-sm);
}

.brand-mark {
    color: var(--primary);
    font-size: 1.35rem;
    font-weight: 800;
}

.brand-avatar {
    font-weight: 700;
    color: #314062;
}

.brand-copy h1,
.brand-copy p,
.page-copy h1,
.page-copy p,
.hero-copy h1,
.hero-copy p,
.metric-card p,
.section-head p,
.auth-intro p,
.empty-state p {
    margin: 0;
}

.brand-copy h1,
.page-copy h1,
.hero-copy h1 {
    font-size: clamp(1.25rem, 2vw, 1.8rem);
    line-height: 1.1;
    letter-spacing: -0.03em;
}

.brand-copy p,
.page-copy p,
.hero-copy p,
.metric-card p,
.section-head p,
.subtle-text,
.table-note,
.empty-state p,
.auth-intro p,
.helper-text {
    color: var(--muted);
}

.nav-links {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.nav-link {
    padding: 12px 16px;
    border-radius: 14px;
    text-decoration: none;
    font-weight: 600;
    color: #465574;
    transition: 0.2s ease;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
    background: var(--primary-soft);
}

.nav-link.logout {
    color: var(--danger);
    background: rgba(239, 68, 68, 0.08);
}

.hero-card,
.panel,
.metric-card,
.date-group,
.auth-panel,
.mini-card,
.table-wrap,
.feature-card {
    border: 1px solid var(--border);
    background: var(--surface);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    backdrop-filter: blur(22px);
}

.hero-card {
    display: grid;
    grid-template-columns: minmax(0, 1.25fr) minmax(280px, 0.75fr);
    gap: 24px;
    padding: 26px;
    margin-bottom: 24px;
}

.hero-copy {
    padding-left: 18px;
    border-left: 5px solid var(--primary);
}

.hero-actions,
.action-row,
.button-row,
.inline-actions,
.toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.hero-stats,
.stats-grid,
.feature-grid,
.auth-grid,
.grid-2,
.grid-3 {
    display: grid;
    gap: 18px;
}

.hero-stats,
.stats-grid {
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
}

.feature-grid {
    grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}

.grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.metric-card,
.mini-card,
.feature-card {
    padding: 22px;
}

.metric-card .metric-value,
.mini-card .metric-value,
.hero-amount {
    display: block;
    margin-top: 8px;
    font-size: clamp(1.7rem, 3.2vw, 2.7rem);
    font-weight: 800;
    letter-spacing: -0.04em;
    color: #25304f;
}

.metric-card .metric-label,
.mini-card .metric-label,
.eyebrow {
    text-transform: uppercase;
    letter-spacing: 0.14em;
    font-size: 0.75rem;
    font-weight: 700;
    color: #8894ac;
}

.panel {
    padding: 24px;
    margin-bottom: 24px;
}

.panel.slim {
    padding: 18px 20px;
}

.section-head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 18px;
}

.section-head h2,
.section-head h3,
.panel h2,
.panel h3,
.date-group h3,
.auth-card h3 {
    margin: 0;
    color: #213053;
    letter-spacing: -0.02em;
}

.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 16px;
}

.field,
.field-stack {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.field label,
.field-stack label {
    font-size: 0.92rem;
    font-weight: 700;
    color: #33415f;
}

.text-input,
.date-picker,
.select-input,
.search-input {
    width: 100%;
    border: 1px solid var(--border);
    background: rgba(248, 250, 254, 0.94);
    color: var(--text);
    padding: 14px 16px;
    border-radius: 16px;
    outline: none;
    transition: 0.2s ease;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.7);
}

.text-input:focus,
.date-picker:focus,
.select-input:focus,
.search-input:focus {
    border-color: rgba(65, 84, 255, 0.45);
    box-shadow: 0 0 0 4px rgba(65, 84, 255, 0.10);
}

.btn,
.submit-btn,
.btn-secondary,
.btn-danger,
.btn-ghost {
    appearance: none;
    border: none;
    border-radius: 16px;
    padding: 14px 18px;
    text-decoration: none;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease, color 0.18s ease;
}

.btn:hover,
.submit-btn:hover,
.btn-secondary:hover,
.btn-danger:hover,
.btn-ghost:hover {
    transform: translateY(-1px);
}

.btn,
.submit-btn {
    color: white;
    background: linear-gradient(135deg, var(--primary), #6b7aff);
    box-shadow: 0 16px 28px rgba(65, 84, 255, 0.22);
}

.btn:hover,
.submit-btn:hover {
    background: linear-gradient(135deg, var(--primary-dark), #5567ff);
}

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

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

.btn-ghost {
    color: #3c4d73;
    background: rgba(148, 163, 184, 0.12);
}

.btn.full,
.submit-btn.full {
    width: 100%;
}

.pill,
.status-pill,
.tag {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 9px 14px;
    border-radius: 999px;
    font-size: 0.9rem;
    font-weight: 700;
}

.pill::before,
.status-pill::before {
    content: "";
    width: 9px;
    height: 9px;
    border-radius: 50%;
    background: currentColor;
    opacity: 0.9;
}

.pill.active,
.status-pill.present {
    color: var(--success);
    background: var(--success-soft);
}

.status-pill.absent {
    color: var(--danger);
    background: var(--danger-soft);
}

.tag {
    background: rgba(148, 163, 184, 0.12);
    color: #4d5c79;
}

.student-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 12px;
}

.student-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 18px 20px;
    border-radius: 20px;
    background: rgba(248, 250, 254, 0.92);
    border: 1px solid rgba(148, 163, 184, 0.15);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

.student-meta {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.student-index {
    font-size: 0.82rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    font-weight: 700;
    color: #7886a2;
}

.student-name {
    font-size: 1rem;
    font-weight: 700;
    color: #233251;
}

.attendance-check {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: 16px;
    background: white;
    border: 1px solid rgba(148, 163, 184, 0.16);
    font-weight: 700;
    color: #30425f;
}

.attendance-check input[type="checkbox"] {
    width: 20px;
    height: 20px;
    accent-color: var(--success);
    margin: 0;
}

.message,
.success-msg,
.error-msg,
.info-msg {
    padding: 14px 16px;
    margin-bottom: 18px;
    border-radius: 16px;
    font-weight: 600;
}

.success-msg {
    color: #0b6a3a;
    background: rgba(16, 185, 129, 0.12);
    border: 1px solid rgba(16, 185, 129, 0.18);
}

.error-msg {
    color: #b42318;
    background: rgba(239, 68, 68, 0.10);
    border: 1px solid rgba(239, 68, 68, 0.16);
}

.info-msg {
    color: #1d4ed8;
    background: rgba(59, 130, 246, 0.10);
    border: 1px solid rgba(59, 130, 246, 0.16);
}

.date-group {
    padding: 22px;
    margin-bottom: 20px;
}

.date-group-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-bottom: 16px;
}

.table-wrap {
    overflow: auto;
    border-radius: 22px;
    background: rgba(255, 255, 255, 0.84);
    box-shadow: none;
}

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

th,
td {
    padding: 15px 16px;
    text-align: left;
    border-bottom: 1px solid rgba(148, 163, 184, 0.16);
}

th {
    font-size: 0.78rem;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: #7d8aa5;
    background: rgba(241, 245, 249, 0.82);
    white-space: nowrap;
}

tbody tr:hover {
    background: rgba(65, 84, 255, 0.04);
}

.table-actions form {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
}

.inline-select {
    min-width: 130px;
}

.auth-panel {
    width: min(1120px, 100%);
    overflow: hidden;
}

.auth-grid {
    grid-template-columns: minmax(0, 1.05fr) minmax(320px, 0.95fr);
}

.auth-intro {
    padding: 34px;
    background: linear-gradient(180deg, rgba(65, 84, 255, 0.14), rgba(65, 84, 255, 0.03));
    border-right: 1px solid rgba(148, 163, 184, 0.12);
}

.auth-card {
    padding: 34px;
}

.auth-stack {
    display: grid;
    gap: 18px;
}

.auth-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 18px;
}

.tab-btn {
    border: none;
    border-radius: 999px;
    padding: 11px 15px;
    font-weight: 700;
    cursor: pointer;
    color: #58688a;
    background: rgba(148, 163, 184, 0.12);
}

.tab-btn.active {
    color: white;
    background: linear-gradient(135deg, var(--primary), #6f7fff);
}

.tab-panel {
    display: none;
}

.tab-panel.active {
    display: block;
}

.divider {
    height: 1px;
    margin: 18px 0;
    background: rgba(148, 163, 184, 0.18);
}

.list-clean {
    margin: 18px 0 0;
    padding-left: 18px;
    color: #42506d;
}

.list-clean li + li {
    margin-top: 10px;
}

.history-list {
    display: grid;
    gap: 12px;
}

.history-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 16px 18px;
    border-radius: 18px;
    background: rgba(248, 250, 254, 0.92);
    border: 1px solid rgba(148, 163, 184, 0.15);
}

.empty-state {
    padding: 28px;
    text-align: center;
    border-radius: 22px;
    background: rgba(248, 250, 254, 0.84);
    border: 1px dashed rgba(148, 163, 184, 0.22);
}

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

.w-auto {
    width: auto;
}

.hidden {
    display: none !important;
}

@media (max-width: 980px) {
    .hero-card,
    .auth-grid {
        grid-template-columns: 1fr;
    }

    .topbar {
        align-items: flex-start;
        flex-direction: column;
    }

    .nav-links {
        width: 100%;
    }
}

@media (max-width: 720px) {
    .app-shell {
        width: min(100% - 20px, 100%);
        margin: 16px auto 30px;
    }

    .topbar,
    .hero-card,
    .panel,
    .metric-card,
    .mini-card,
    .date-group,
    .auth-intro,
    .auth-card {
        padding: 18px;
    }

    .student-item,
    .history-item,
    .date-group-header,
    .section-head {
        flex-direction: column;
        align-items: stretch;
    }

    .table-actions form,
    .button-row,
    .toolbar,
    .hero-actions,
    .action-row {
        flex-direction: column;
        align-items: stretch;
    }

    .btn,
    .submit-btn,
    .btn-secondary,
    .btn-danger,
    .btn-ghost,
    .tab-btn {
        width: 100%;
        text-align: center;
    }

    th,
    td {
        padding: 13px 12px;
    }
}