:root {
    --bg: #f6f7fb;
    --surface: #ffffff;
    --surface-2: #eef2f8;
    --text: #182033;
    --muted: #667085;
    --line: #d9e0ea;
    --primary: #1267d8;
    --primary-2: #12a594;
    --accent: #f59e0b;
    --danger: #dc2626;
    --success: #138a53;
    --shadow: 0 18px 45px rgba(24, 32, 51, .11);
    --radius: 8px;
}

[data-theme="dark"] {
    --bg: #10131a;
    --surface: #171c26;
    --surface-2: #222938;
    --text: #eef2ff;
    --muted: #aab4c7;
    --line: #30394b;
    --primary: #5da2ff;
    --primary-2: #39c6b5;
    --accent: #fbbf24;
    --shadow: 0 18px 45px rgba(0, 0, 0, .35);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    min-height: 100vh;
    background:
        radial-gradient(circle at 12% 8%, color-mix(in srgb, var(--primary) 12%, transparent), transparent 24rem),
        radial-gradient(circle at 88% 0%, color-mix(in srgb, var(--primary-2) 12%, transparent), transparent 22rem),
        var(--bg);
    color: var(--text);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
    line-height: 1.5;
    transition: background .25s ease, color .25s ease;
}

a {
    color: inherit;
    text-decoration: none;
}

img,
video {
    max-width: 100%;
}

.topbar {
    position: sticky;
    top: 0;
    z-index: 10;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 18px;
    padding: 14px clamp(16px, 4vw, 48px);
    background: color-mix(in srgb, var(--surface) 92%, transparent);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(14px);
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    letter-spacing: 0;
}

.brand span {
    display: grid;
    place-items: center;
    width: 38px;
    height: 38px;
    color: white;
    background: linear-gradient(135deg, var(--primary), var(--primary-2));
    border-radius: var(--radius);
}

.nav {
    display: flex;
    align-items: center;
    gap: 14px;
    color: var(--muted);
    font-weight: 600;
}

.nav a:hover,
.link-button:hover {
    color: var(--primary);
}

.pill,
.button,
.icon-button {
    border: 0;
    border-radius: var(--radius);
    cursor: pointer;
    font: inherit;
    font-weight: 800;
}

.pill {
    padding: 9px 13px;
    background: var(--surface-2);
    color: var(--text);
}

.icon-button {
    width: 38px;
    height: 38px;
    background: var(--surface-2);
    color: var(--text);
}

.inline-form {
    display: inline;
}

.link-button {
    padding: 0;
    color: var(--muted);
    background: transparent;
    border: 0;
    cursor: pointer;
    font: inherit;
    font-weight: 600;
}

.page {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
    padding: 28px 0 56px;
}

.hero {
    display: grid;
    grid-template-columns: minmax(0, 1.4fr) minmax(260px, .6fr);
    gap: 26px;
    align-items: stretch;
    min-height: 430px;
    padding: clamp(28px, 7vw, 72px);
    background:
        linear-gradient(135deg, color-mix(in srgb, var(--primary) 20%, transparent), transparent 38%),
        var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.hero h1 {
    max-width: 760px;
    margin: 8px 0 16px;
    font-size: clamp(2rem, 6vw, 4.4rem);
    line-height: 1;
    letter-spacing: 0;
}

.hero p {
    max-width: 650px;
    color: var(--muted);
    font-size: 1.08rem;
}

.eyebrow {
    margin: 0;
    color: var(--primary-2);
    text-transform: uppercase;
    font-size: .78rem;
    font-weight: 900;
    letter-spacing: .12em;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 28px;
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 11px 16px;
    transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
}

.button:hover {
    transform: translateY(-2px);
}

.button.primary {
    color: white;
    background: linear-gradient(135deg, var(--primary), var(--primary-2));
    box-shadow: 0 10px 25px color-mix(in srgb, var(--primary) 28%, transparent);
}

.button.ghost {
    color: var(--text);
    background: var(--surface-2);
}

.hero-panel {
    display: grid;
    align-content: center;
    gap: 10px;
    padding: 28px;
    background: var(--surface-2);
    border-radius: var(--radius);
    animation: panelFloat 5s ease-in-out infinite;
}

.hero-panel strong {
    font-size: 3.2rem;
    line-height: 1;
}

.hero-panel span {
    color: var(--muted);
    font-weight: 700;
}

.feature-band {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
    margin-top: 24px;
}

.feature-band article,
.db-warning {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.feature-band article {
    overflow: hidden;
    animation: rise .55s ease forwards;
}

.feature-band img {
    display: block;
    width: 100%;
    height: 150px;
    object-fit: cover;
}

.feature-band h3 {
    margin: 16px 16px 6px;
}

.feature-band p {
    margin: 0 16px 18px;
    color: var(--muted);
}

.db-warning {
    display: grid;
    gap: 10px;
    margin-top: 24px;
    padding: 20px;
    border-color: color-mix(in srgb, var(--danger) 45%, var(--line));
}

.db-warning h2 {
    margin: 0;
}

.db-warning p {
    margin: 0;
    color: var(--muted);
}

.db-warning code {
    display: block;
    width: fit-content;
    max-width: 100%;
    padding: 8px 10px;
    overflow-wrap: anywhere;
    color: var(--text);
    background: var(--surface-2);
    border-radius: var(--radius);
}

.section {
    margin-top: 36px;
}

.section-heading {
    display: flex;
    justify-content: space-between;
    align-items: end;
    gap: 16px;
    margin-bottom: 16px;
}

.section h2,
.panel h1,
.admin-content h1 {
    margin: 4px 0 18px;
    font-size: clamp(1.55rem, 3vw, 2.25rem);
}

.course-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.course-card,
.panel,
.auth-card,
.course-detail,
.player-shell,
.review-box,
.certificate {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.course-card {
    overflow: hidden;
    transform: translateY(12px);
    opacity: 0;
    animation: rise .55s ease forwards;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 22px 52px color-mix(in srgb, var(--primary) 16%, transparent);
}

.course-cover,
.detail-cover {
    min-height: 190px;
    background-position: center;
    background-size: cover;
}

.course-body {
    padding: 18px;
}

.tag {
    display: inline-flex;
    margin-bottom: 10px;
    color: var(--primary);
    font-size: .82rem;
    font-weight: 900;
}

.course-body h3 {
    margin: 0 0 8px;
    font-size: 1.2rem;
}

.course-body p,
.detail-info p,
.panel p,
.auth-card p {
    color: var(--muted);
}

.meta {
    display: flex;
    justify-content: space-between;
    gap: 10px;
    margin-top: 14px;
    color: var(--muted);
    font-size: .9rem;
    font-weight: 700;
}

.meta a {
    color: var(--primary);
}

.auth-card,
.panel {
    width: min(760px, 100%);
    margin: 34px auto;
    padding: clamp(22px, 5vw, 38px);
}

.demo-login-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin: 18px 0;
}

.demo-login-card {
    display: grid;
    gap: 4px;
    padding: 14px;
    color: var(--text);
    text-align: left;
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    cursor: pointer;
    font: inherit;
    transition: transform .2s ease, border-color .2s ease, box-shadow .2s ease;
}

.demo-login-card:hover {
    transform: translateY(-2px);
    border-color: var(--primary);
    box-shadow: 0 12px 28px color-mix(in srgb, var(--primary) 16%, transparent);
}

.demo-login-card span,
.demo-login-card small,
.empty-state {
    color: var(--muted);
}

.two-cols,
.course-detail {
    display: grid;
    grid-template-columns: .8fr 1.2fr;
    gap: 24px;
    align-items: start;
}

.form {
    display: grid;
    gap: 14px;
}

.form label {
    display: grid;
    gap: 6px;
    color: var(--muted);
    font-weight: 800;
}

input,
select,
textarea {
    width: 100%;
    min-height: 42px;
    padding: 11px 12px;
    color: var(--text);
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    font: inherit;
    transition: border-color .2s ease, box-shadow .2s ease, background .2s ease;
}

input:focus,
select:focus,
textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px color-mix(in srgb, var(--primary) 15%, transparent);
}

textarea {
    resize: vertical;
}

.compact {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    align-items: end;
}

.grid-form {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-form textarea,
.grid-form button {
    grid-column: 1 / -1;
}

.avatar-preview {
    width: 112px;
    height: 112px;
    object-fit: cover;
    border-radius: 50%;
    border: 4px solid var(--surface-2);
}

.certificates-panel {
    width: min(960px, 100%);
}

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

.certificate-item {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 16px;
    align-items: center;
    padding: 16px;
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.certificate-item h3 {
    margin: 0 0 6px;
}

.certificate-item p {
    margin: 0;
    color: var(--muted);
}

.course-detail {
    overflow: hidden;
}

.detail-info {
    padding: clamp(22px, 4vw, 36px);
}

.progress {
    height: 12px;
    margin: 18px 0 8px;
    background: var(--surface-2);
    border-radius: 999px;
    overflow: hidden;
}

.progress span {
    display: block;
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--accent));
}

.lesson-list {
    display: grid;
    gap: 10px;
}

.lesson-item {
    display: grid;
    grid-template-columns: 42px 1fr auto;
    gap: 14px;
    align-items: center;
    padding: 14px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    transition: transform .2s ease, border-color .2s ease, background .2s ease;
}

.lesson-item:not(.locked):hover {
    transform: translateX(4px);
    border-color: color-mix(in srgb, var(--primary) 45%, var(--line));
}

.lesson-item > span {
    display: grid;
    place-items: center;
    width: 38px;
    height: 38px;
    color: white;
    background: var(--primary);
    border-radius: var(--radius);
    font-weight: 900;
}

.lesson-item small {
    display: block;
    color: var(--muted);
}

.lesson-item.locked {
    opacity: .55;
    pointer-events: none;
}

.lesson-item.completed {
    opacity: .68;
    background: color-mix(in srgb, var(--surface-2) 78%, #808080);
}

.lesson-item.completed strong {
    color: var(--muted);
    text-decoration: line-through;
}

.lesson-item.completed > span {
    background: var(--muted);
}

.lesson-item.completed em {
    color: var(--success);
    font-weight: 900;
}

.review-box {
    display: grid;
    gap: 14px;
    margin-top: 20px;
    padding: 20px;
}

.stars {
    display: inline-flex;
    flex-direction: row-reverse;
    justify-content: flex-end;
    gap: 4px;
}

.stars input {
    display: none;
}

.stars label {
    color: var(--line);
    cursor: pointer;
    font-size: 2rem;
}

.stars input:checked ~ label,
.stars label:hover,
.stars label:hover ~ label {
    color: var(--accent);
}

.player-shell {
    display: grid;
    gap: 18px;
    padding: clamp(18px, 4vw, 32px);
}

.video-player {
    width: 100%;
    max-height: 70vh;
    background: #05070a;
    border-radius: var(--radius);
}

.video-placeholder {
    display: grid;
    place-items: center;
    gap: 10px;
    min-height: 340px;
    padding: 24px;
    color: white;
    text-align: center;
    background:
        linear-gradient(135deg, rgba(18, 103, 216, .9), rgba(18, 165, 148, .86)),
        #10131a;
    border-radius: var(--radius);
}

.video-placeholder strong {
    font-size: clamp(1.6rem, 4vw, 2.6rem);
}

.video-placeholder span {
    max-width: 620px;
    color: rgba(255, 255, 255, .85);
}

.admin-layout {
    display: grid;
    grid-template-columns: 230px minmax(0, 1fr);
    gap: 20px;
}

.admin-menu {
    position: sticky;
    top: 82px;
    align-self: start;
    display: grid;
    gap: 8px;
    padding: 14px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.admin-menu a {
    padding: 11px 12px;
    color: var(--muted);
    border-radius: var(--radius);
    font-weight: 800;
}

.admin-menu a:hover {
    color: var(--text);
    background: var(--surface-2);
}

.admin-content {
    min-width: 0;
    padding: clamp(18px, 4vw, 28px);
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.admin-content h2 {
    margin: 26px 0 8px;
    font-size: 1.25rem;
}

.admin-note {
    margin: 0;
    color: var(--muted);
}

.lesson-course-picker {
    margin-bottom: 18px;
}

.lesson-admin-header {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 16px;
    align-items: center;
    margin-bottom: 18px;
    padding: 18px;
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.lesson-admin-header h2 {
    margin: 4px 0 6px;
    font-size: 1.45rem;
}

.lesson-admin-header p {
    margin: 0;
    color: var(--muted);
}

.lesson-upload-form {
    margin-bottom: 20px;
}

.admin-lesson-list .lesson-item {
    background: var(--surface-2);
}

.stat-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 14px;
}

.stat {
    padding: 20px;
    background: var(--surface-2);
    border-radius: var(--radius);
}

.stat strong {
    display: block;
    font-size: 2.3rem;
}

.stat span {
    color: var(--muted);
    text-transform: capitalize;
    font-weight: 800;
}

.table-wrap {
    margin-top: 18px;
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    min-width: 620px;
}

.review-report-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    margin-top: 14px;
}

.review-report-card {
    padding: 16px;
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.review-report-card p {
    margin: 10px 0;
}

.review-report-card small {
    color: var(--muted);
    font-weight: 700;
}

th,
td {
    padding: 12px;
    border-bottom: 1px solid var(--line);
    text-align: left;
    vertical-align: top;
}

th {
    color: var(--muted);
    font-size: .82rem;
    text-transform: uppercase;
    letter-spacing: .08em;
}

.row-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    align-items: center;
}

.row-actions form {
    margin: 0;
}

.mini-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 32px;
    padding: 7px 10px;
    color: var(--text);
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    cursor: pointer;
    font: inherit;
    font-size: .82rem;
    font-weight: 900;
    white-space: nowrap;
}

.mini-button:hover {
    border-color: var(--primary);
}

.mini-button.warning {
    color: #1f1600;
    background: #f8c34a;
    border-color: #f8c34a;
}

.mini-button.danger {
    color: white;
    background: var(--danger);
    border-color: var(--danger);
}

.mini-button.success {
    color: white;
    background: var(--success);
    border-color: var(--success);
}

.status-badge {
    display: inline-flex;
    align-items: center;
    min-height: 28px;
    padding: 5px 9px;
    border-radius: 999px;
    font-size: .78rem;
    font-weight: 900;
    white-space: nowrap;
}

.status-badge.active {
    color: #04351f;
    background: #9bf0c3;
}

.status-badge.blocked {
    color: #45120f;
    background: #ffc1bd;
}

.inline-modal {
    display: none;
    width: min(420px, 80vw);
    margin-top: 10px;
    padding: 12px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.inline-modal.wide {
    width: min(760px, 80vw);
}

.inline-modal.open {
    display: block;
}

.certificate-tools {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 18px;
}

.certificate {
    width: min(900px, 100%);
    margin: 0 auto;
    padding: clamp(32px, 7vw, 76px);
    text-align: center;
    background:
        linear-gradient(135deg, color-mix(in srgb, var(--primary) 13%, transparent), transparent 45%),
        var(--surface);
}

.certificate h1 {
    margin: 0;
    color: var(--primary);
    font-size: clamp(2.2rem, 6vw, 4rem);
}

.certificate h2 {
    margin: 20px 0 10px;
    font-size: clamp(2rem, 5vw, 3.6rem);
}

.certificate h3 {
    font-size: clamp(1.4rem, 4vw, 2.5rem);
}

.certificate-row {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    margin-top: 38px;
    color: var(--muted);
    font-weight: 800;
}

.flash {
    width: min(1180px, calc(100% - 32px));
    margin: 18px auto 0;
    padding: 12px 14px;
    color: white;
    background: var(--success);
    border-radius: var(--radius);
}

.flash.danger {
    background: var(--danger);
}

.flash.warning {
    background: var(--accent);
    color: #1c1607;
}

.footer {
    display: flex;
    justify-content: space-between;
    gap: 16px;
    padding: 24px clamp(16px, 4vw, 48px);
    color: var(--muted);
    border-top: 1px solid var(--line);
}

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

@keyframes panelFloat {
    0%,
    100% {
        transform: translateY(0);
    }

    50% {
        transform: translateY(-8px);
    }
}

@media (max-width: 900px) {
    .hero,
    .two-cols,
    .course-detail,
    .lesson-admin-header,
    .admin-layout {
        grid-template-columns: 1fr;
    }

    .course-grid,
    .feature-band,
    .demo-login-grid,
    .review-report-grid,
    .stat-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .admin-menu {
        position: static;
        grid-template-columns: repeat(4, minmax(0, 1fr));
    }

    .compact,
    .grid-form {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .topbar,
    .nav,
    .footer,
    .certificate-row {
        align-items: stretch;
        flex-direction: column;
    }

    .nav {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .course-grid,
    .feature-band,
    .demo-login-grid,
    .certificate-item,
    .review-report-grid,
    .stat-grid,
    .admin-menu {
        grid-template-columns: 1fr;
    }

    .hero {
        padding: 24px;
        min-height: auto;
    }

    .lesson-item {
        grid-template-columns: 36px 1fr;
    }

    .lesson-item em {
        grid-column: 2;
    }
}

@media print {
    .topbar,
    .footer,
    .certificate-tools,
    .flash {
        display: none;
    }

    body {
        background: white;
    }

    .page {
        width: 100%;
        padding: 0;
    }

    .certificate {
        border: 8px solid #1267d8;
        box-shadow: none;
    }
}