:root {
    --bg: #f7f9fc;
    --surface: #ffffff;
    --surface-soft: #eef4ff;
    --ink: #172033;
    --muted: #667085;
    --line: #d8e0ee;
    --accent: #2563eb;
    --accent-2: #0f766e;
    --warn: #b45309;
    --code: #101828;
    --radius: 8px;
    --shadow: 0 16px 36px rgba(16, 24, 40, 0.08);
    --font: "Microsoft YaHei", "PingFang SC", "Segoe UI", Arial, sans-serif;
    --mono: Consolas, "SFMono-Regular", monospace;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--ink);
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.7;
}

a {
    color: inherit;
}

img {
    display: block;
    max-width: 100%;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 32px;
    background: rgba(255, 255, 255, 0.94);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(14px);
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    color: var(--ink);
    text-decoration: none;
}

.brand-mark {
    width: 40px;
    height: 40px;
    display: grid;
    place-items: center;
    border-radius: var(--radius);
    background: var(--ink);
    color: #fff;
    font-weight: 800;
    font-size: 13px;
}

.brand strong,
.brand small {
    display: block;
    line-height: 1.25;
}

.brand small {
    color: var(--muted);
    font-size: 12px;
}

.top-nav {
    display: flex;
    align-items: center;
    gap: 22px;
    font-size: 14px;
}

.top-nav a {
    color: #344054;
    text-decoration: none;
}

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

.layout {
    display: grid;
    grid-template-columns: 248px minmax(0, 1fr);
    gap: 32px;
    max-width: 1440px;
    margin: 0 auto;
    padding: 28px 32px 64px;
}

.side-nav {
    position: sticky;
    top: 96px;
    align-self: start;
    display: flex;
    flex-direction: column;
    gap: 4px;
    padding: 18px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.side-title {
    margin: 0 0 8px;
    color: var(--muted);
    font-size: 13px;
    font-weight: 700;
}

.side-nav a {
    padding: 8px 10px;
    border-radius: 6px;
    color: #344054;
    text-decoration: none;
    font-size: 14px;
}

.side-nav a:hover,
.side-nav a.active {
    background: var(--surface-soft);
    color: var(--accent);
}

.content {
    min-width: 0;
}

.hero,
.section {
    margin-bottom: 28px;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.hero {
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(360px, 0.85fr);
    gap: 28px;
    align-items: center;
    padding: 42px;
}

.hero h1 {
    margin: 0;
    max-width: 760px;
    font-size: 42px;
    line-height: 1.18;
    letter-spacing: 0;
}

.lead {
    margin: 18px 0 0;
    max-width: 760px;
    color: #475467;
    font-size: 18px;
}

.eyebrow {
    margin: 0 0 10px;
    color: var(--accent-2);
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0;
    text-transform: uppercase;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 26px;
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 40px;
    padding: 8px 14px;
    border: 1px solid var(--line);
    border-radius: 6px;
    background: #fff;
    color: var(--ink);
    text-decoration: none;
    font-weight: 700;
}

.button.primary {
    border-color: var(--accent);
    background: var(--accent);
    color: #fff;
}

.hero-media {
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: #111827;
}

.section {
    padding: 34px;
}

.section-heading {
    margin-bottom: 22px;
}

.section-heading h2,
.warning h2 {
    margin: 0;
    font-size: 28px;
    line-height: 1.25;
}

.section-heading p {
    margin: 10px 0 0;
    color: var(--muted);
}

.steps,
.feature-list,
.preview-grid,
.walkthrough-grid,
.sandbox {
    display: grid;
    gap: 16px;
}

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

.step,
.feature-list article,
.walkthrough-grid article,
figure,
.note,
.sandbox {
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: #fff;
}

.step {
    padding: 18px;
}

.step span {
    width: 28px;
    height: 28px;
    display: grid;
    place-items: center;
    border-radius: 999px;
    background: var(--surface-soft);
    color: var(--accent);
    font-weight: 800;
}

.step h3,
.feature-list h3 {
    margin: 14px 0 6px;
    font-size: 18px;
}

.step p,
.feature-list p,
.note p,
details p,
.warning p {
    margin: 0;
    color: #475467;
}

.step a {
    display: inline-block;
    margin-top: 12px;
    color: var(--accent);
    font-weight: 700;
}

.code-block {
    position: relative;
    margin-top: 16px;
    border-radius: var(--radius);
    background: var(--code);
    color: #e5e7eb;
}

.code-block pre {
    margin: 0;
    padding: 22px;
    overflow-x: auto;
}

.code-block code {
    font-family: var(--mono);
    font-size: 14px;
}

.copy-button {
    position: absolute;
    top: 10px;
    right: 10px;
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 6px;
    background: rgba(255, 255, 255, 0.08);
    color: #fff;
    cursor: pointer;
    padding: 5px 10px;
}

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

.timeline li {
    display: grid;
    grid-template-columns: 170px minmax(0, 1fr);
    gap: 16px;
    padding: 14px 0;
    border-bottom: 1px solid var(--line);
}

.timeline li:last-child {
    border-bottom: 0;
}

.timeline strong {
    color: var(--ink);
}

.timeline span {
    color: #475467;
}

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

.feature-list article,
.walkthrough-grid article {
    padding: 18px;
}

.walkthrough-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
}

.walkthrough-grid span {
    display: inline-flex;
    padding: 2px 8px;
    border-radius: 999px;
    background: var(--surface-soft);
    color: var(--accent);
    font-size: 12px;
    font-weight: 800;
}

.walkthrough-grid h3 {
    margin: 12px 0 6px;
    font-size: 17px;
}

.walkthrough-grid p {
    margin: 0;
    color: #475467;
    font-size: 14px;
}

.tip-box {
    margin-top: 16px;
    padding: 14px 16px;
    border: 1px solid #bfdbfe;
    border-radius: var(--radius);
    background: #eff6ff;
    color: #344054;
}

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

figure {
    margin: 0;
    overflow: hidden;
}

figcaption {
    padding: 12px 14px;
    color: #475467;
    font-size: 14px;
    border-top: 1px solid var(--line);
}

.split {
    display: grid;
    grid-template-columns: minmax(0, 1fr) 320px;
    gap: 24px;
}

table {
    width: 100%;
    border-collapse: collapse;
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

th,
td {
    padding: 12px 14px;
    border-bottom: 1px solid var(--line);
    text-align: left;
    vertical-align: top;
}

th {
    background: var(--surface-soft);
}

tr:last-child td {
    border-bottom: 0;
}

.note {
    padding: 18px;
    background: #fffbeb;
    border-color: #fde68a;
}

.note h3 {
    margin: 0 0 8px;
    color: var(--warn);
}

.sandbox {
    grid-template-columns: minmax(0, 1fr) minmax(260px, 0.6fr);
    padding: 20px;
    align-items: center;
}

.sandbox-controls {
    display: grid;
    gap: 14px;
}

.sandbox-controls label {
    display: grid;
    gap: 6px;
    color: #344054;
    font-weight: 700;
}

.control-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.control-row strong {
    min-width: 72px;
    padding: 2px 8px;
    border-radius: 999px;
    background: var(--surface-soft);
    color: var(--accent);
    font-size: 13px;
    text-align: center;
}

.sandbox-result {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 10px;
}

.sandbox-result div {
    padding: 14px;
    border-radius: var(--radius);
    background: var(--surface-soft);
}

.sandbox-result span,
.sandbox-result strong {
    display: block;
}

.sandbox-result span {
    color: var(--muted);
    font-size: 13px;
}

.sandbox-result strong {
    margin-top: 6px;
    color: var(--accent);
    font-size: 22px;
}

details {
    padding: 16px 0;
    border-bottom: 1px solid var(--line);
}

details:last-child {
    border-bottom: 0;
}

summary {
    cursor: pointer;
    font-weight: 800;
}

details p {
    margin-top: 10px;
}

.warning {
    border-color: #fbbf24;
    background: #fffbeb;
}

.toast {
    position: fixed;
    right: 24px;
    bottom: 24px;
    z-index: 40;
    padding: 10px 14px;
    border-radius: 6px;
    background: var(--ink);
    color: #fff;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 160ms ease, transform 160ms ease;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 1100px) {
    .layout {
        grid-template-columns: 1fr;
    }

    .side-nav {
        position: static;
        flex-direction: row;
        overflow-x: auto;
    }

    .side-title {
        display: none;
    }

    .hero,
    .split,
    .sandbox {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 760px) {
    .site-header {
        height: auto;
        align-items: flex-start;
        flex-direction: column;
        gap: 12px;
        padding: 14px 18px;
    }

    .top-nav {
        width: 100%;
        overflow-x: auto;
        gap: 16px;
        padding-bottom: 2px;
    }

    .layout {
        padding: 18px;
    }

    .hero,
    .section {
        padding: 22px;
    }

    .hero h1 {
        font-size: 30px;
    }

    .steps,
    .feature-list,
    .preview-grid,
    .walkthrough-grid,
    .sandbox-result {
        grid-template-columns: 1fr;
    }

    .timeline li {
        grid-template-columns: 1fr;
        gap: 4px;
    }
}