:root {
    --color-primary: #f54e00;
    --color-primary-active: #d04200;
    --color-canvas: #f7f7f4;
    --color-canvas-soft: #fafaf7;
    --color-surface-card: #ffffff;
    --color-surface-strong: #e6e5e0;
    --color-hairline: #e6e5e0;
    --color-hairline-soft: #efeee8;
    --color-hairline-strong: #cfcdc4;
    --color-ink: #26251e;
    --color-body: #5a5852;
    --color-muted: #807d72;
    --color-muted-soft: #a09c92;
    --color-on-primary: #ffffff;
    --color-success: #1f8a65;
    --color-error: #cf2d56;
    --font-sans: 'Inter', system-ui, 'Helvetica Neue', Helvetica, Arial, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-pill: 9999px;
    --spacing-section: 80px;
    --max-width: 1200px;
    --sidebar-width: 260px;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    font-weight: 400;
    line-height: 1.5;
    color: var(--color-body);
    background: var(--color-canvas);
    -webkit-font-smoothing: antialiased;
}

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

a {
    color: var(--color-ink);
    text-decoration: none;
}

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

.skip-link {
    position: absolute;
    top: -100px;
    left: 16px;
    background: var(--color-ink);
    color: var(--color-canvas);
    padding: 8px 16px;
    border-radius: var(--radius-md);
    z-index: 1000;
}

.skip-link:focus {
    top: 16px;
}

.site-header {
    background: var(--color-canvas);
    border-bottom: 1px solid var(--color-hairline);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--color-ink);
}

.logo-mark {
    background: var(--color-primary);
    color: var(--color-on-primary);
    font-size: 13px;
    font-weight: 600;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-text {
    font-size: 18px;
    font-weight: 400;
    letter-spacing: -0.02em;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--color-ink);
}

.top-nav ul {
    display: flex;
    gap: 24px;
    list-style: none;
}

.top-nav a {
    font-size: 14px;
    font-weight: 500;
    color: var(--color-ink);
}

.layout-wrapper {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    gap: 48px;
    padding: 32px 24px var(--spacing-section);
}

.sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    position: sticky;
    top: 96px;
    align-self: flex-start;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
}

.sidebar-section {
    margin-bottom: 28px;
}

.sidebar-heading {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.88px;
    color: var(--color-muted);
    margin-bottom: 12px;
}

.sidebar-nav ul {
    list-style: none;
}

.sidebar-nav a {
    display: block;
    font-size: 14px;
    padding: 6px 0;
    color: var(--color-body);
    border-left: 2px solid transparent;
    padding-left: 12px;
    margin-left: -12px;
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
    color: var(--color-ink);
    border-left-color: var(--color-primary);
}

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

.main-content--home {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px var(--spacing-section);
}

.breadcrumb ol {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    list-style: none;
    font-size: 13px;
    margin-bottom: 24px;
    color: var(--color-muted);
}

.breadcrumb li:not(:last-child)::after {
    content: '/';
    margin-left: 8px;
    color: var(--color-muted-soft);
}

.breadcrumb a {
    color: var(--color-muted);
}

.toc {
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin-bottom: 32px;
}

.toc-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: 16px;
}

.toc ol {
    list-style: none;
    counter-reset: toc;
}

.toc li {
    counter-increment: toc;
    margin-bottom: 8px;
}

.toc a {
    font-size: 14px;
    color: var(--color-body);
    display: flex;
    gap: 8px;
}

.toc a::before {
    content: counter(toc) '.';
    color: var(--color-muted);
    min-width: 20px;
}

.article-header {
    margin-bottom: 32px;
}

.article-header h1 {
    font-size: clamp(28px, 5vw, 36px);
    font-weight: 400;
    letter-spacing: -0.72px;
    line-height: 1.2;
    color: var(--color-ink);
    margin-bottom: 16px;
}

.article-meta {
    font-size: 14px;
    color: var(--color-muted);
}

.article-body h2 {
    font-size: 26px;
    font-weight: 400;
    letter-spacing: -0.325px;
    color: var(--color-ink);
    margin: 48px 0 16px;
    scroll-margin-top: 96px;
}

.article-body h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-ink);
    margin: 32px 0 12px;
    scroll-margin-top: 96px;
}

.article-body p {
    margin-bottom: 16px;
    font-size: 16px;
    line-height: 1.6;
}

.article-body ul,
.article-body ol {
    margin: 0 0 16px 24px;
}

.article-body li {
    margin-bottom: 8px;
}

.article-body img {
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-hairline);
    margin: 24px 0;
}

.figure-caption {
    font-size: 13px;
    color: var(--color-muted);
    margin-top: -16px;
    margin-bottom: 24px;
}

.code-block {
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    padding: 20px;
    margin: 16px 0 24px;
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 13px;
    line-height: 1.5;
    color: var(--color-ink);
}

code {
    font-family: var(--font-mono);
    font-size: 13px;
    background: var(--color-surface-strong);
    padding: 2px 6px;
    border-radius: 4px;
}

.info-box {
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    padding: 24px;
    margin: 24px 0;
}

.info-box h3 {
    margin-top: 0;
}

.disclaimer-block {
    background: var(--color-canvas-soft);
    border: 1px solid var(--color-hairline-soft);
    border-radius: var(--radius-lg);
    padding: 20px;
    margin: 32px 0;
    font-size: 14px;
    color: var(--color-muted);
}

.related-content {
    margin-top: 48px;
    padding-top: 32px;
    border-top: 1px solid var(--color-hairline);
}

.related-title {
    font-size: 22px;
    font-weight: 400;
    letter-spacing: -0.11px;
    color: var(--color-ink);
    margin-bottom: 20px;
}

.related-list {
    list-style: none;
    display: grid;
    gap: 12px;
}

.related-list a {
    display: block;
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    padding: 16px 20px;
}

.related-item-title {
    display: block;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: 4px;
}

.related-item-desc {
    display: block;
    font-size: 14px;
    color: var(--color-muted);
}

.hero-band {
    padding: var(--spacing-section) 0 48px;
    text-align: center;
}

.hero-band h1 {
    font-size: clamp(32px, 8vw, 72px);
    font-weight: 400;
    letter-spacing: -2.16px;
    line-height: 1.1;
    color: var(--color-ink);
    margin-bottom: 24px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.hero-sub {
    font-size: 18px;
    color: var(--color-body);
    max-width: 640px;
    margin: 0 auto 32px;
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 500;
    border-radius: var(--radius-md);
    padding: 10px 18px;
    height: 40px;
    border: none;
    cursor: pointer;
    font-family: var(--font-sans);
    transition: background 0.15s;
}

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

.btn-primary:hover {
    background: var(--color-primary-active);
    color: var(--color-on-primary);
}

.btn-secondary {
    background: var(--color-surface-card);
    color: var(--color-ink);
    border: 1px solid var(--color-hairline-strong);
}

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

.btn-ink {
    background: var(--color-ink);
    color: var(--color-canvas);
    padding: 12px 20px;
    height: 44px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin: 48px 0;
}

.feature-card {
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    padding: 24px;
}

.feature-card h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 15px;
    color: var(--color-body);
    margin-bottom: 16px;
}

.feature-card a {
    font-size: 14px;
    font-weight: 500;
    color: var(--color-primary);
}

.section-band {
    padding: var(--spacing-section) 0;
}

.section-band h2 {
    font-size: 36px;
    font-weight: 400;
    letter-spacing: -0.72px;
    color: var(--color-ink);
    margin-bottom: 32px;
    text-align: center;
}

.ide-mockup {
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    overflow: hidden;
    max-width: 720px;
    margin: 0 auto;
}

.ide-pane {
    background: var(--color-canvas-soft);
    padding: 16px;
    font-family: var(--font-mono);
    font-size: 13px;
    color: var(--color-body);
    border-top: 1px solid var(--color-hairline);
}

.ide-pane:first-child {
    border-top: none;
}

.faq-section {
    max-width: 720px;
    margin: 0 auto;
}

.faq-item {
    border: 1px solid var(--color-hairline);
    border-radius: var(--radius-lg);
    margin-bottom: 12px;
    background: var(--color-surface-card);
}

.faq-item summary {
    padding: 16px 20px;
    font-weight: 600;
    color: var(--color-ink);
    cursor: pointer;
    list-style: none;
}

.faq-item summary::-webkit-details-marker {
    display: none;
}

.faq-item[open] summary {
    border-bottom: 1px solid var(--color-hairline);
}

.faq-answer {
    padding: 16px 20px;
    font-size: 15px;
}

.read-more-block {
    position: relative;
}

.read-more-content {
    max-height: 120px;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.read-more-content.expanded {
    max-height: none;
}

.read-more-toggle {
    background: none;
    border: none;
    color: var(--color-primary);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    padding: 8px 0;
    font-family: var(--font-sans);
}

.contact-form {
    max-width: 560px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: 8px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    background: var(--color-surface-card);
    border: 1px solid var(--color-hairline-strong);
    border-radius: var(--radius-md);
    padding: 12px 16px;
    height: 44px;
    font-size: 16px;
    font-family: var(--font-sans);
    color: var(--color-ink);
}

.form-group textarea {
    height: auto;
    min-height: 120px;
    resize: vertical;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 0;
}

.form-group input.error {
    border-color: var(--color-error);
}

.form-error {
    font-size: 13px;
    color: var(--color-error);
    margin-top: 6px;
}

.form-success {
    background: var(--color-surface-card);
    border: 1px solid var(--color-success);
    border-radius: var(--radius-lg);
    padding: 16px 20px;
    color: var(--color-success);
    margin-bottom: 24px;
}

.form-loading {
    opacity: 0.6;
    pointer-events: none;
}

.comparison-table {
    width: 100%;
    border-collapse: collapse;
    margin: 24px 0;
    font-size: 14px;
}

.comparison-table th,
.comparison-table td {
    border: 1px solid var(--color-hairline);
    padding: 12px 16px;
    text-align: left;
}

.comparison-table th {
    background: var(--color-surface-strong);
    font-weight: 600;
    color: var(--color-ink);
}

.comparison-table tr:nth-child(even) {
    background: var(--color-surface-card);
}

.site-footer {
    background: var(--color-canvas);
    border-top: 1px solid var(--color-hairline);
    padding: 48px 24px 32px;
}

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
}

.footer-columns {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
    margin-bottom: 32px;
}

.footer-heading {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: 16px;
}

.footer-col ul {
    list-style: none;
}

.footer-col li {
    margin-bottom: 8px;
}

.footer-col a {
    font-size: 14px;
    color: var(--color-body);
}

.footer-legal {
    border-top: 1px solid var(--color-hairline);
    padding-top: 24px;
    margin-bottom: 24px;
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 16px 24px;
    list-style: none;
}

.footer-links a {
    font-size: 13px;
    color: var(--color-muted);
}

.footer-disclaimers {
    font-size: 13px;
    color: var(--color-muted);
    line-height: 1.6;
    margin-bottom: 24px;
}

.footer-disclaimers p {
    margin-bottom: 8px;
}

.footer-copy {
    font-size: 13px;
    color: var(--color-muted-soft);
}

.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--color-surface-card);
    border-top: 1px solid var(--color-hairline);
    padding: 20px 24px;
    z-index: 200;
}

.cookie-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    flex-wrap: wrap;
}

.cookie-inner p {
    font-size: 14px;
    flex: 1;
    min-width: 240px;
}

.cookie-actions {
    display: flex;
    gap: 12px;
}

.badge-pill {
    display: inline-block;
    background: var(--color-surface-strong);
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.88px;
    padding: 4px 10px;
    border-radius: var(--radius-pill);
    color: var(--color-ink);
    margin-bottom: 12px;
}

@media (max-width: 1024px) {
    .layout-wrapper {
        flex-direction: column;
        gap: 24px;
    }

    .sidebar {
        width: 100%;
        position: static;
        max-height: none;
        border-bottom: 1px solid var(--color-hairline);
        padding-bottom: 24px;
    }

    .sidebar-nav {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
        gap: 24px;
    }
}

@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .top-nav {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--color-canvas);
        border-bottom: 1px solid var(--color-hairline);
        padding: 16px 24px;
    }

    .top-nav.open {
        display: block;
    }

    .top-nav ul {
        flex-direction: column;
        gap: 12px;
    }

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

    .cookie-inner {
        flex-direction: column;
        align-items: stretch;
    }

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

@media (max-width: 640px) {
    .hero-band h1 {
        letter-spacing: -1px;
    }

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