/* Chalk-Walrus Teacher Dashboard — Warm, clean, professional */

:root {
    --chalk-green: #2D5016;
    --chalk-green-light: #4A7C28;
    --chalk-green-faint: #E8F0E0;
    --chalk-cream: #FFF8F0;
    --chalk-warm: #F5EDE3;
    --chalk-sand: #E8DDD0;
    --chalk-text: #2C2420;
    --chalk-text-light: #6B5E52;
    --chalk-white: #FFFFFF;
    --chalk-accent: #D4853A;
    --chalk-accent-light: #F0C78A;
    --chalk-error: #C0392B;
    --chalk-success: #27AE60;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 2px 8px rgba(44, 36, 32, 0.08);
    --shadow-lg: 0 4px 16px rgba(44, 36, 32, 0.12);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--chalk-cream);
    color: var(--chalk-text);
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
}

/* --- Layout --- */

.page {
    max-width: 800px;
    margin: 0 auto;
    padding: 24px 16px;
}

.page-narrow {
    max-width: 480px;
}

/* --- Top bar --- */

.topbar {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 16px 24px 8px;
    background: var(--chalk-green);
    color: var(--chalk-white);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 50;
}

.topbar .brand {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    text-decoration: none;
    color: var(--chalk-white);
    margin-bottom: 10px;
}

.topbar .brand-logo {
    width: 72px;
    height: 72px;
    border-radius: 14px;
    border: 2px solid rgba(255,255,255,0.25);
    box-shadow: 0 2px 12px rgba(0,0,0,0.2);
}

.topbar .brand-name {
    font-family: 'Georgia', 'Times New Roman', serif;
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 1px;
}

.admin-pill {
    display: inline-block;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--chalk-accent);
    color: #fff;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 1px;
    padding: 2px 8px;
    border-radius: 4px;
    vertical-align: middle;
    margin-left: 4px;
}

.topbar nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 4px;
    margin-bottom: 4px;
}

.topbar nav a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    padding: 6px 14px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 500;
    letter-spacing: 0.3px;
    transition: background 0.2s, color 0.2s;
}

.topbar nav a:hover,
.topbar nav a.active {
    background: rgba(255, 255, 255, 0.15);
    color: var(--chalk-white);
}

.topbar .logout-btn {
    position: absolute;
    top: 16px;
    right: 20px;
    background: none;
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: var(--chalk-white);
    padding: 6px 14px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 12px;
    transition: background 0.2s;
}

.topbar .topbar-wrap {
    position: relative;
    width: 100%;
}

.topbar .logout-btn:hover {
    background: rgba(255, 255, 255, 0.15);
}

/* --- Cards --- */

.card {
    background: var(--chalk-white);
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 16px;
    box-shadow: var(--shadow);
}

.card h2 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--chalk-green);
}

.card h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 8px;
}

/* --- Forms --- */

.form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 6px;
    color: var(--chalk-text);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 10px 14px;
    border: 2px solid var(--chalk-sand);
    border-radius: var(--radius-sm);
    font-size: 15px;
    background: var(--chalk-cream);
    color: var(--chalk-text);
    outline: none;
    transition: border-color 0.2s;
    font-family: inherit;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    border-color: var(--chalk-green);
}

.form-group textarea {
    min-height: 100px;
    resize: vertical;
}

.form-group .help-text {
    font-size: 12px;
    color: var(--chalk-text-light);
    margin-top: 4px;
}

/* --- Buttons --- */

.btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 20px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    transition: background 0.2s, transform 0.1s;
    text-decoration: none;
}

.btn:active {
    transform: scale(0.98);
}

.btn-primary {
    background: var(--chalk-green);
    color: var(--chalk-white);
}

.btn-primary:hover {
    background: var(--chalk-green-light);
}

.btn-secondary {
    background: var(--chalk-warm);
    color: var(--chalk-text);
}

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

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

.btn-danger:hover {
    background: #A93226;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 13px;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-group {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

/* --- Auth pages --- */

.auth-page {
    display: flex;
    min-height: 100vh;
    justify-content: center;
    align-items: center;
    padding: 24px;
    background: linear-gradient(160deg, var(--chalk-cream) 0%, var(--chalk-warm) 100%);
}

.auth-card {
    background: var(--chalk-white);
    border-radius: var(--radius);
    padding: 32px;
    width: 100%;
    max-width: 400px;
    box-shadow: var(--shadow-lg);
    text-align: center;
}

.auth-card .logo {
    font-size: 48px;
    margin-bottom: 8px;
}

.auth-card h1 {
    font-size: 24px;
    color: var(--chalk-green);
    margin-bottom: 4px;
}

.auth-card .subtitle {
    color: var(--chalk-text-light);
    font-size: 14px;
    margin-bottom: 24px;
}

.auth-card form {
    text-align: left;
}

.auth-card .auth-link {
    margin-top: 16px;
    text-align: center;
    font-size: 14px;
    color: var(--chalk-text-light);
}

.auth-card .auth-link a {
    color: var(--chalk-green);
    font-weight: 500;
    text-decoration: none;
}

.auth-card .auth-link a:hover {
    text-decoration: underline;
}

/* --- Stats --- */

.stat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 12px;
    margin-bottom: 16px;
}

.stat-card {
    background: var(--chalk-green-faint);
    border-radius: var(--radius-sm);
    padding: 16px;
    text-align: center;
}

.stat-card .stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--chalk-green);
}

.stat-card .stat-label {
    font-size: 13px;
    color: var(--chalk-text-light);
    margin-top: 4px;
}

/* --- Lists --- */

.item-list {
    list-style: none;
}

.item-list li {
    padding: 12px 16px;
    border-bottom: 1px solid var(--chalk-sand);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
}

.item-list li:last-child {
    border-bottom: none;
}

.item-list .item-main {
    flex: 1;
    min-width: 0;
}

.item-list .item-title {
    font-weight: 600;
    font-size: 15px;
}

.item-list .item-meta {
    font-size: 13px;
    color: var(--chalk-text-light);
    margin-top: 2px;
}

.item-list .item-preview {
    font-size: 14px;
    color: var(--chalk-text-light);
    margin-top: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* --- Tags/Badges --- */

.badge {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 500;
}

.badge-green {
    background: var(--chalk-green-faint);
    color: var(--chalk-green);
}

.badge-orange {
    background: var(--chalk-accent-light);
    color: var(--chalk-accent);
}

/* --- Empty state --- */

.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--chalk-text-light);
}

.empty-state .empty-icon {
    font-size: 48px;
    margin-bottom: 12px;
}

.empty-state p {
    margin-bottom: 16px;
}

/* --- Wizard / Onboarding --- */

.wizard-steps {
    display: flex;
    gap: 4px;
    margin-bottom: 24px;
}

.wizard-step {
    flex: 1;
    height: 4px;
    background: var(--chalk-sand);
    border-radius: 2px;
    transition: background 0.3s;
}

.wizard-step.active {
    background: var(--chalk-green);
}

.wizard-step.done {
    background: var(--chalk-green-light);
}

.wizard-panel {
    display: none;
}

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

/* --- Alerts --- */

.alert {
    padding: 12px 16px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    margin-bottom: 16px;
}

.alert-success {
    background: #E8F5E9;
    color: #1B5E20;
    border: 1px solid #A5D6A7;
}

.alert-error {
    background: #FFEBEE;
    color: #B71C1C;
    border: 1px solid #EF9A9A;
}

.alert-info {
    background: var(--chalk-green-faint);
    color: var(--chalk-green);
    border: 1px solid #C8E6C9;
}

/* --- Share link --- */

.share-link {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--chalk-cream);
    padding: 10px 14px;
    border-radius: var(--radius-sm);
    border: 2px solid var(--chalk-sand);
    margin-top: 8px;
}

.share-link code {
    flex: 1;
    font-size: 14px;
    color: var(--chalk-green);
    word-break: break-all;
}

.share-link .copy-btn {
    padding: 6px 12px;
    background: var(--chalk-green);
    color: var(--chalk-white);
    border: none;
    border-radius: var(--radius-sm);
    font-size: 13px;
    cursor: pointer;
    white-space: nowrap;
}

.share-link .copy-btn:hover {
    background: var(--chalk-green-light);
}

/* --- Hero Banner --- */

.hero-banner {
    position: relative;
    width: 100%;
    height: 220px;
    overflow: hidden;
    background: var(--chalk-green);
}

.hero-banner .hero-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center 30%;
    opacity: 0.85;
}

.hero-banner .hero-overlay {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 24px 32px;
    background: linear-gradient(transparent, rgba(45, 80, 22, 0.9));
    color: #fff;
}

.hero-banner .hero-overlay h1 {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 4px;
    text-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.hero-banner .hero-overlay p {
    font-size: 15px;
    opacity: 0.9;
    text-shadow: 0 1px 4px rgba(0,0,0,0.2);
}

.share-card {
    margin-top: -24px;
    position: relative;
    z-index: 5;
    border: 2px solid var(--chalk-green-faint);
}

@media (max-width: 600px) {
    .hero-banner {
        height: 160px;
    }
    .hero-banner .hero-overlay {
        padding: 16px 20px;
    }
    .hero-banner .hero-overlay h1 {
        font-size: 20px;
    }
}

/* --- Modal --- */

.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.4);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 100;
    padding: 24px;
}

.modal-overlay.hidden {
    display: none;
}

.modal {
    background: var(--chalk-white);
    border-radius: var(--radius);
    padding: 24px;
    width: 100%;
    max-width: 500px;
    box-shadow: var(--shadow-lg);
    max-height: 80vh;
    overflow-y: auto;
}

.modal h2 {
    font-size: 18px;
    color: var(--chalk-green);
    margin-bottom: 16px;
}

/* --- Admin page --- */

.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 24px 16px;
}

.container h1 {
    font-size: 24px;
    color: var(--chalk-green);
    margin-bottom: 20px;
}

.topbar-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.topbar-brand .logo {
    font-size: 18px;
    font-weight: 700;
}

.topbar-brand .badge {
    background: var(--chalk-accent);
    color: #fff;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 1px;
    padding: 2px 8px;
    border-radius: 4px;
}

.hint {
    font-size: 13px;
    color: var(--chalk-text-light);
    margin-bottom: 12px;
}

.share-link-box {
    display: flex;
    gap: 8px;
    margin-top: 8px;
}

.share-link-box input {
    flex: 1;
    padding: 10px 14px;
    border: 2px solid var(--chalk-sand);
    border-radius: var(--radius-sm);
    font-size: 14px;
    background: var(--chalk-cream);
    color: var(--chalk-green);
    font-family: monospace;
}

.status-msg {
    margin-left: 12px;
    font-size: 14px;
}

.status-msg.success {
    color: var(--chalk-success);
}

.info-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    font-size: 14px;
}

.invite-result {
    margin-top: 16px;
    padding: 16px;
    background: var(--chalk-green-faint);
    border-radius: var(--radius-sm);
}

.invite-result label {
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 6px;
    display: block;
}

.tester-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid var(--chalk-sand);
}

.tester-actions {
    display: flex;
    gap: 6px;
}

.btn-small {
    padding: 4px 10px;
    font-size: 12px;
}

.danger-zone {
    border: 2px solid var(--chalk-error);
}

.danger-zone h2 {
    color: var(--chalk-error);
}

.danger-actions {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--chalk-sand);
    gap: 16px;
}

.danger-actions:last-child {
    border-bottom: none;
}

.hidden {
    display: none !important;
}

/* --- Version tag --- */

.version-tag {
    position: fixed;
    bottom: 10px;
    right: 12px;
    font-size: 11px;
    font-weight: 500;
    color: var(--chalk-text-light);
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--chalk-sand);
    padding: 3px 9px;
    border-radius: 20px;
    z-index: 40;
    pointer-events: none;
    letter-spacing: 0.2px;
    box-shadow: var(--shadow);
}

/* --- Loading spinner --- */

.spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid var(--chalk-sand);
    border-top-color: var(--chalk-green);
    border-radius: 50%;
    animation: cw-spin 0.7s linear infinite;
    vertical-align: middle;
}

.loading-row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 24px 0;
    color: var(--chalk-text-light);
    font-size: 14px;
}

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

/* --- Table scroll wrapper (mobile) --- */

.table-scroll {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.table-scroll table {
    min-width: 560px;
}

/* --- Small empty state (inline lists) --- */

.empty-state-sm {
    text-align: center;
    padding: 18px 12px;
    color: var(--chalk-text-light);
    font-size: 14px;
}

/* --- Responsive --- */

@media (max-width: 600px) {
    .topbar {
        flex-direction: column;
        gap: 8px;
    }

    .topbar nav {
        width: 100%;
        justify-content: center;
    }

    .topbar nav a {
        padding: 6px 10px;
        font-size: 12px;
    }

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

    .version-tag {
        bottom: 6px;
        right: 6px;
        font-size: 10px;
        padding: 2px 7px;
    }

    .info-grid {
        grid-template-columns: 1fr;
    }

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

    .share-link-box {
        flex-wrap: wrap;
    }
}