@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600&family=JetBrains+Mono:wght@400&display=swap');

:root {
    --color-canvas: #f7f7f4;
    --color-canvas-soft: #fafaf7;
    --color-surface-card: #ffffff;
    --color-surface-strong: #e6e5e0;
    --color-primary: #f54e00;
    --color-primary-active: #d04200;
    --color-on-primary: #ffffff;
    --color-ink: #26251e;
    --color-body: #5a5852;
    --color-body-strong: #26251e;
    --color-muted: #807d72;
    --color-muted-soft: #a09c92;
    --color-hairline: #e6e5e0;
    --color-hairline-soft: #efeee8;
    --color-hairline-strong: #cfcdc4;
    --color-timeline-thinking: #dfa88f;
    --color-timeline-grep: #9fc9a2;
    --color-timeline-read: #9fbbe0;
    --color-timeline-edit: #c0a8dd;
    --color-timeline-done: #c08532;
    --color-semantic-success: #1f8a65;
    --color-semantic-error: #cf2d56;

    --rounded-none: 0px;
    --rounded-xs: 4px;
    --rounded-sm: 6px;
    --rounded-md: 8px;
    --rounded-lg: 12px;
    --rounded-xl: 16px;
    --rounded-pill: 9999px;

    --spacing-xxs: 4px;
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-base: 16px;
    --spacing-md: 20px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-xxl: 48px;
    --spacing-section: 80px;
}

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

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

body {
    font-family: 'Inter', system-ui, 'Helvetica Neue', Helvetica, Arial, sans-serif;
    background-color: var(--color-canvas);
    color: var(--color-body);
    font-size: 16px;
    font-weight: 400;
    line-height: 1.5;
    letter-spacing: 0;
    -webkit-font-smoothing: antialiased;
}

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

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

code, pre, .code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    line-height: 1.5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-xl);
}

.top-nav {
    background-color: var(--color-canvas);
    border-bottom: 1px solid var(--color-hairline);
    height: 64px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.top-nav .nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-wordmark {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-ink);
    letter-spacing: -0.3px;
    line-height: 1;
}

.nav-wordmark span {
    color: var(--color-primary);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
    list-style: none;
}

.nav-menu a {
    font-size: 14px;
    font-weight: 500;
    line-height: 1.4;
    color: var(--color-body);
    transition: color 0.15s ease;
}

.nav-menu a:hover {
    color: var(--color-ink);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.hamburger {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
    padding: 4px;
    background: none;
    border: none;
}

.hamburger span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--color-ink);
    border-radius: 2px;
    transition: all 0.2s ease;
}

.btn-primary {
    background-color: var(--color-primary);
    color: var(--color-on-primary);
    font-size: 14px;
    font-weight: 500;
    line-height: 1.0;
    padding: 10px 18px;
    height: 40px;
    border-radius: var(--rounded-md);
    border: none;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    transition: background-color 0.15s ease;
}

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

.btn-secondary {
    background-color: var(--color-surface-card);
    color: var(--color-ink);
    font-size: 14px;
    font-weight: 500;
    line-height: 1.0;
    padding: 10px 18px;
    height: 40px;
    border-radius: var(--rounded-md);
    border: 1px solid var(--color-hairline-strong);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    transition: border-color 0.15s ease;
}

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

.hero-band {
    padding: var(--spacing-section) 0;
    background-color: var(--color-canvas);
    border-bottom: 1px solid var(--color-hairline);
}

.hero-band .hero-label {
    font-size: 11px;
    font-weight: 600;
    line-height: 1.4;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--color-muted);
    margin-bottom: var(--spacing-md);
}

.hero-band h1 {
    font-size: 72px;
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -2.16px;
    color: var(--color-ink);
    max-width: 800px;
    margin-bottom: var(--spacing-lg);
}

.hero-band .hero-sub {
    font-size: 16px;
    font-weight: 400;
    line-height: 1.5;
    color: var(--color-body);
    max-width: 520px;
    margin-bottom: var(--spacing-xl);
}

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

.section-label {
    font-size: 11px;
    font-weight: 600;
    line-height: 1.4;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--color-muted);
    margin-bottom: var(--spacing-base);
}

.display-lg {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--color-ink);
    margin-bottom: var(--spacing-lg);
}

.display-md {
    font-size: 26px;
    font-weight: 400;
    line-height: 1.25;
    letter-spacing: -0.325px;
    color: var(--color-ink);
    margin-bottom: var(--spacing-base);
}

.display-sm {
    font-size: 22px;
    font-weight: 400;
    line-height: 1.3;
    letter-spacing: -0.11px;
    color: var(--color-ink);
    margin-bottom: var(--spacing-sm);
}

.title-md {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-ink);
    margin-bottom: var(--spacing-sm);
}

.title-sm {
    font-size: 16px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-ink);
    margin-bottom: var(--spacing-xs);
}

.body-sm {
    font-size: 14px;
    font-weight: 400;
    line-height: 1.5;
    color: var(--color-body);
}

.body-tracked {
    font-size: 16px;
    font-weight: 400;
    line-height: 1.5;
    letter-spacing: 0.08px;
    color: var(--color-body);
}

.caption-uppercase {
    font-size: 11px;
    font-weight: 600;
    line-height: 1.4;
    letter-spacing: 0.88px;
    text-transform: uppercase;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

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

.feature-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: var(--rounded-md);
    margin-bottom: var(--spacing-base);
}

.feature-card .card-label {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--color-muted);
    margin-bottom: var(--spacing-xs);
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-ink);
    margin-bottom: var(--spacing-sm);
}

.feature-card p {
    font-size: 14px;
    font-weight: 400;
    line-height: 1.5;
    color: var(--color-body);
    margin-bottom: var(--spacing-base);
}

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

.feature-card a:hover {
    color: var(--color-primary-active);
}

.badge-pill {
    display: inline-flex;
    align-items: center;
    background-color: var(--color-surface-strong);
    color: var(--color-ink);
    font-size: 11px;
    font-weight: 600;
    line-height: 1.4;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    border-radius: var(--rounded-pill);
    padding: 4px 10px;
}

.divider {
    border: none;
    border-top: 1px solid var(--color-hairline);
    margin: 0;
}

.article-hero {
    padding: var(--spacing-section) 0 var(--spacing-xl);
    background-color: var(--color-canvas);
    border-bottom: 1px solid var(--color-hairline);
}

.article-hero .breadcrumb {
    font-size: 13px;
    color: var(--color-muted);
    margin-bottom: var(--spacing-base);
}

.article-hero .breadcrumb a {
    color: var(--color-muted);
    transition: color 0.15s ease;
}

.article-hero .breadcrumb a:hover {
    color: var(--color-ink);
}

.article-hero .breadcrumb span {
    margin: 0 6px;
}

.article-hero h1 {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--color-ink);
    max-width: 700px;
    margin-bottom: var(--spacing-base);
}

.article-hero .article-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-base);
    font-size: 13px;
    color: var(--color-muted);
    flex-wrap: wrap;
}

.article-layout {
    display: grid;
    grid-template-columns: 1fr 280px;
    gap: var(--spacing-section);
    padding: var(--spacing-section) 0;
    align-items: start;
}

.article-content h2 {
    font-size: 26px;
    font-weight: 400;
    line-height: 1.25;
    letter-spacing: -0.325px;
    color: var(--color-ink);
    margin-top: var(--spacing-xxl);
    margin-bottom: var(--spacing-base);
}

.article-content h3 {
    font-size: 18px;
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-ink);
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-sm);
}

.article-content p {
    font-size: 16px;
    font-weight: 400;
    line-height: 1.5;
    color: var(--color-body);
    margin-bottom: var(--spacing-base);
}

.article-content ul, .article-content ol {
    padding-left: var(--spacing-xl);
    margin-bottom: var(--spacing-base);
}

.article-content li {
    font-size: 16px;
    line-height: 1.5;
    color: var(--color-body);
    margin-bottom: var(--spacing-xs);
}

.article-content .article-img {
    width: 100%;
    border-radius: var(--rounded-lg);
    margin: var(--spacing-xl) 0;
    border: 1px solid var(--color-hairline);
}

.article-content .img-caption {
    font-size: 13px;
    color: var(--color-muted);
    margin-top: calc(-1 * var(--spacing-base));
    margin-bottom: var(--spacing-xl);
}

.article-content .note-block {
    background-color: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-left: 3px solid var(--color-timeline-read);
    border-radius: var(--rounded-md);
    padding: var(--spacing-base) var(--spacing-lg);
    margin: var(--spacing-xl) 0;
}

.article-content .note-block p {
    margin-bottom: 0;
    font-size: 14px;
}

.article-content .tool-table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--spacing-xl) 0;
    font-size: 14px;
}

.article-content .tool-table th {
    background-color: var(--color-surface-strong);
    color: var(--color-ink);
    font-weight: 600;
    font-size: 11px;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    padding: var(--spacing-sm) var(--spacing-base);
    text-align: left;
    border-bottom: 1px solid var(--color-hairline-strong);
}

.article-content .tool-table td {
    padding: var(--spacing-sm) var(--spacing-base);
    border-bottom: 1px solid var(--color-hairline-soft);
    color: var(--color-body);
    vertical-align: top;
}

.article-content .tool-table tr:last-child td {
    border-bottom: none;
}

.article-sidebar {
    position: sticky;
    top: 80px;
}

.sidebar-card {
    background-color: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--rounded-lg);
    padding: var(--spacing-base);
    margin-bottom: var(--spacing-base);
}

.sidebar-card h4 {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--color-muted);
    margin-bottom: var(--spacing-sm);
}

.sidebar-toc {
    list-style: none;
}

.sidebar-toc li {
    padding: 6px 0;
    border-bottom: 1px solid var(--color-hairline-soft);
}

.sidebar-toc li:last-child {
    border-bottom: none;
}

.sidebar-toc a {
    font-size: 14px;
    color: var(--color-body);
    transition: color 0.15s ease;
}

.sidebar-toc a:hover {
    color: var(--color-ink);
}

.related-articles {
    list-style: none;
}

.related-articles li {
    padding: 8px 0;
    border-bottom: 1px solid var(--color-hairline-soft);
}

.related-articles li:last-child {
    border-bottom: none;
}

.related-articles a {
    font-size: 14px;
    color: var(--color-body);
    transition: color 0.15s ease;
}

.related-articles a:hover {
    color: var(--color-ink);
}

.cta-band {
    background-color: var(--color-canvas);
    border-top: 1px solid var(--color-hairline);
    padding: 96px 0;
    text-align: center;
}

.cta-band h2 {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--color-ink);
    margin-bottom: var(--spacing-base);
}

.cta-band p {
    font-size: 16px;
    color: var(--color-body);
    margin-bottom: var(--spacing-xl);
}

.footer {
    background-color: var(--color-canvas);
    border-top: 1px solid var(--color-hairline);
    padding: 64px 0 48px;
}

.footer-inner {
    display: grid;
    grid-template-columns: 2fr repeat(4, 1fr);
    gap: var(--spacing-xl);
}

.footer-brand .footer-wordmark {
    font-size: 18px;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: var(--spacing-sm);
}

.footer-brand .footer-wordmark span {
    color: var(--color-primary);
}

.footer-brand p {
    font-size: 14px;
    color: var(--color-body);
    line-height: 1.5;
    max-width: 240px;
}

.footer-col h5 {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--color-muted);
    margin-bottom: var(--spacing-sm);
}

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

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

.footer-col ul li a {
    font-size: 14px;
    color: var(--color-body);
    transition: color 0.15s ease;
}

.footer-col ul li a:hover {
    color: var(--color-ink);
}

.footer-bottom {
    margin-top: var(--spacing-xxl);
    padding-top: var(--spacing-base);
    border-top: 1px solid var(--color-hairline-soft);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--spacing-base);
}

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

.footer-bottom a {
    font-size: 13px;
    color: var(--color-muted);
    transition: color 0.15s ease;
}

.footer-bottom a:hover {
    color: var(--color-ink);
}

.contact-section {
    padding: var(--spacing-section) 0;
    background-color: var(--color-canvas);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-section);
    align-items: start;
}

.contact-form {
    background-color: var(--color-surface-card);
    border: 1px solid var(--color-hairline);
    border-radius: var(--rounded-lg);
    padding: var(--spacing-xl);
}

.form-group {
    margin-bottom: var(--spacing-base);
}

.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--color-ink);
    margin-bottom: 6px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    background-color: var(--color-surface-card);
    color: var(--color-ink);
    border: 1px solid var(--color-hairline-strong);
    border-radius: var(--rounded-md);
    padding: 12px 16px;
    height: 44px;
    font-size: 16px;
    font-family: inherit;
    transition: border-color 0.15s ease;
    outline: none;
}

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

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

.form-message {
    display: none;
    padding: var(--spacing-sm) var(--spacing-base);
    border-radius: var(--rounded-md);
    font-size: 14px;
    margin-top: var(--spacing-sm);
}

.form-message.success {
    background-color: #e6f4ef;
    color: var(--color-semantic-success);
    border: 1px solid #b3ddd1;
}

.contact-info h3 {
    font-size: 26px;
    font-weight: 400;
    letter-spacing: -0.325px;
    color: var(--color-ink);
    margin-bottom: var(--spacing-base);
}

.contact-info p {
    font-size: 16px;
    color: var(--color-body);
    line-height: 1.5;
    margin-bottom: var(--spacing-base);
}

.contact-info address {
    font-style: normal;
    font-size: 14px;
    color: var(--color-body);
    line-height: 1.8;
}

.page-hero {
    padding: var(--spacing-section) 0 var(--spacing-xl);
    border-bottom: 1px solid var(--color-hairline);
}

.page-hero h1 {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--color-ink);
    margin-bottom: var(--spacing-sm);
}

.page-hero p {
    font-size: 16px;
    color: var(--color-body);
    max-width: 600px;
}

.page-content {
    max-width: 740px;
    padding: var(--spacing-section) 0;
}

.page-content h2 {
    font-size: 22px;
    font-weight: 400;
    letter-spacing: -0.11px;
    color: var(--color-ink);
    margin-top: var(--spacing-xxl);
    margin-bottom: var(--spacing-base);
}

.page-content h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--color-ink);
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-sm);
}

.page-content p {
    font-size: 16px;
    color: var(--color-body);
    line-height: 1.5;
    margin-bottom: var(--spacing-base);
}

.page-content ul, .page-content ol {
    padding-left: var(--spacing-xl);
    margin-bottom: var(--spacing-base);
}

.page-content li {
    font-size: 16px;
    color: var(--color-body);
    line-height: 1.5;
    margin-bottom: var(--spacing-xs);
}

.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: var(--color-surface-card);
    border-top: 1px solid var(--color-hairline);
    padding: var(--spacing-base) var(--spacing-xl);
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
}

.cookie-banner p {
    font-size: 14px;
    color: var(--color-body);
    flex: 1;
    min-width: 260px;
}

.cookie-banner p a {
    color: var(--color-primary);
    text-decoration: underline;
    text-underline-offset: 2px;
}

.cookie-actions {
    display: flex;
    gap: var(--spacing-sm);
    flex-shrink: 0;
}

.disclaimer-bar {
    background-color: var(--color-surface-strong);
    border-bottom: 1px solid var(--color-hairline);
    padding: 8px 0;
    text-align: center;
    font-size: 12px;
    color: var(--color-muted);
}

.breadcrumb-nav {
    font-size: 13px;
    color: var(--color-muted);
    padding: var(--spacing-base) 0;
}

.breadcrumb-nav a {
    color: var(--color-muted);
    transition: color 0.15s ease;
}

.breadcrumb-nav a:hover {
    color: var(--color-ink);
}

.breadcrumb-nav span {
    margin: 0 6px;
}

@media (max-width: 1024px) {
    .hero-band h1 {
        font-size: 56px;
        letter-spacing: -1.5px;
    }
    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-inner {
        grid-template-columns: repeat(2, 1fr);
    }
    .article-layout {
        grid-template-columns: 1fr;
    }
    .article-sidebar {
        position: static;
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-base);
    }
    .nav-menu {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background-color: var(--color-canvas);
        border-bottom: 1px solid var(--color-hairline);
        padding: var(--spacing-base);
        flex-direction: column;
        gap: 0;
    }
    .nav-menu.open {
        display: flex;
    }
    .nav-menu li {
        width: 100%;
    }
    .nav-menu a {
        display: block;
        padding: var(--spacing-sm) 0;
        border-bottom: 1px solid var(--color-hairline-soft);
    }
    .hamburger {
        display: flex;
    }
    .hero-band h1 {
        font-size: 32px;
        letter-spacing: -0.8px;
    }
    .display-lg {
        font-size: 28px;
    }
    .grid-3, .grid-2 {
        grid-template-columns: 1fr;
    }
    .footer-inner {
        grid-template-columns: 1fr;
    }
    .contact-grid {
        grid-template-columns: 1fr;
    }
    .cookie-banner {
        flex-direction: column;
        align-items: flex-start;
    }
    .article-hero h1 {
        font-size: 26px;
    }
}

@media (max-width: 640px) {
    :root {
        --spacing-section: 48px;
    }
}