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

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

:root {
    --canvas: #f7f7f4;
    --canvas-soft: #fafaf7;
    --surface-card: #ffffff;
    --surface-strong: #e6e5e0;
    --primary: #f54e00;
    --primary-active: #d04200;
    --ink: #26251e;
    --body-color: #5a5852;
    --muted: #807d72;
    --muted-soft: #a09c92;
    --on-primary: #ffffff;
    --hairline: #e6e5e0;
    --hairline-soft: #efeee8;
    --hairline-strong: #cfcdc4;
    --success: #1f8a65;
    --error: #cf2d56;
}

html { scroll-behavior: smooth; }

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

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

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

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

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

.top-nav .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

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

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

.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    font-size: 14px;
    font-weight: 500;
    color: var(--body-color);
    transition: color 0.15s;
}

.nav-links a:hover, .nav-links a.active { color: var(--ink); }

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

.nav-hamburger span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--ink);
    transition: 0.2s;
}

.hero {
    padding: 80px 0;
    background: var(--canvas);
    border-bottom: 1px solid var(--hairline);
}

.hero-eyebrow {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 16px;
}

.hero h1 {
    font-size: 56px;
    font-weight: 400;
    line-height: 1.1;
    letter-spacing: -1.5px;
    color: var(--ink);
    max-width: 760px;
    margin-bottom: 20px;
}

.hero p {
    font-size: 18px;
    color: var(--body-color);
    max-width: 580px;
    line-height: 1.6;
    margin-bottom: 32px;
}

.hero-meta {
    font-size: 13px;
    color: var(--muted);
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.hero-meta span::before { content: '·'; margin-right: 16px; }
.hero-meta span:first-child::before { content: ''; margin-right: 0; }

.section { padding: 80px 0; }
.section-sm { padding: 48px 0; }

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

.section-title {
    font-size: 36px;
    font-weight: 400;
    line-height: 1.2;
    letter-spacing: -0.72px;
    color: var(--ink);
    margin-bottom: 16px;
}

.section-sub {
    font-size: 22px;
    font-weight: 400;
    line-height: 1.25;
    letter-spacing: -0.11px;
    color: var(--ink);
    margin-bottom: 12px;
}

.section-body { font-size: 16px; color: var(--body-color); max-width: 640px; line-height: 1.6; }

.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }

.card {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: 12px;
    padding: 24px;
}

.card-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
    margin-bottom: 16px;
}

.card-label {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 8px;
}

.card-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--ink);
    line-height: 1.4;
    margin-bottom: 8px;
}

.card-title a { color: var(--ink); }
.card-title a:hover { color: var(--primary); }

.card-excerpt {
    font-size: 14px;
    color: var(--body-color);
    line-height: 1.5;
    margin-bottom: 16px;
}

.card-meta {
    font-size: 13px;
    color: var(--muted);
}

.badge {
    display: inline-block;
    background: var(--surface-strong);
    color: var(--ink);
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    border-radius: 9999px;
    padding: 4px 10px;
}

.divider { height: 1px; background: var(--hairline); margin: 0; }

.article-hero {
    padding: 64px 0 48px;
    border-bottom: 1px solid var(--hairline);
}

.article-hero h1 {
    font-size: 42px;
    font-weight: 400;
    line-height: 1.15;
    letter-spacing: -0.8px;
    color: var(--ink);
    max-width: 780px;
    margin-bottom: 16px;
}

.article-layout { display: grid; grid-template-columns: 1fr 300px; gap: 48px; padding: 48px 0; }

.article-body h2 {
    font-size: 26px;
    font-weight: 400;
    line-height: 1.25;
    letter-spacing: -0.325px;
    color: var(--ink);
    margin: 40px 0 16px;
}

.article-body h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--ink);
    margin: 28px 0 12px;
}

.article-body p { font-size: 16px; color: var(--body-color); line-height: 1.7; margin-bottom: 20px; }

.article-body ul, .article-body ol {
    padding-left: 24px;
    margin-bottom: 20px;
}

.article-body li { font-size: 16px; color: var(--body-color); line-height: 1.7; margin-bottom: 6px; }

.article-body img { border-radius: 8px; margin: 24px 0; width: 100%; }

.article-body .note {
    background: var(--canvas-soft);
    border: 1px solid var(--hairline);
    border-left: 3px solid var(--primary);
    border-radius: 8px;
    padding: 16px 20px;
    margin: 24px 0;
    font-size: 14px;
    color: var(--body-color);
}

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

.sidebar-card {
    background: var(--surface-card);
    border: 1px solid var(--hairline);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 16px;
}

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

.sidebar-links { list-style: none; }
.sidebar-links li { border-bottom: 1px solid var(--hairline-soft); }
.sidebar-links li:last-child { border-bottom: none; }
.sidebar-links a { display: block; padding: 8px 0; font-size: 14px; color: var(--body-color); }
.sidebar-links a:hover { color: var(--ink); }

.toc-list { list-style: none; counter-reset: toc; }
.toc-list li { counter-increment: toc; border-bottom: 1px solid var(--hairline-soft); }
.toc-list li:last-child { border-bottom: none; }
.toc-list a {
    display: flex;
    gap: 10px;
    padding: 8px 0;
    font-size: 14px;
    color: var(--body-color);
    align-items: start;
}
.toc-list a::before {
    content: counter(toc);
    font-size: 11px;
    color: var(--muted);
    min-width: 16px;
    margin-top: 2px;
}
.toc-list a:hover { color: var(--ink); }

.page-hero {
    padding: 64px 0 48px;
    border-bottom: 1px solid var(--hairline);
}

.page-hero h1 {
    font-size: 42px;
    font-weight: 400;
    letter-spacing: -0.8px;
    color: var(--ink);
    margin-bottom: 12px;
}

.page-content { max-width: 740px; padding: 48px 0; }
.page-content h2 { font-size: 22px; font-weight: 400; color: var(--ink); margin: 32px 0 12px; letter-spacing: -0.11px; }
.page-content h3 { font-size: 16px; font-weight: 600; color: var(--ink); margin: 20px 0 8px; }
.page-content p { color: var(--body-color); line-height: 1.7; margin-bottom: 16px; }
.page-content ul { padding-left: 20px; margin-bottom: 16px; }
.page-content li { color: var(--body-color); line-height: 1.7; margin-bottom: 4px; }

.form-group { margin-bottom: 20px; }
.form-label { display: block; font-size: 14px; font-weight: 500; color: var(--ink); margin-bottom: 6px; }
.form-input {
    width: 100%;
    height: 44px;
    padding: 12px 16px;
    font-size: 16px;
    font-family: inherit;
    color: var(--ink);
    background: var(--surface-card);
    border: 1px solid var(--hairline-strong);
    border-radius: 8px;
    outline: none;
    transition: border-color 0.15s;
}
.form-input:focus { border-color: var(--ink); }
.form-textarea { height: 120px; resize: vertical; }
.form-error { font-size: 13px; color: var(--error); margin-top: 4px; display: none; }
.form-error.show { display: block; }

.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 40px;
    padding: 10px 18px;
    font-size: 14px;
    font-weight: 500;
    color: var(--on-primary);
    background: var(--primary);
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.15s;
    font-family: inherit;
}
.btn-primary:hover, .btn-primary:focus { background: var(--primary-active); color: var(--on-primary); }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; }

.btn-secondary {
    display: inline-flex;
    align-items: center;
    height: 40px;
    padding: 10px 18px;
    font-size: 14px;
    font-weight: 500;
    color: var(--ink);
    background: var(--surface-card);
    border: 1px solid var(--hairline-strong);
    border-radius: 8px;
    cursor: pointer;
    transition: border-color 0.15s;
    font-family: inherit;
}
.btn-secondary:hover { border-color: var(--ink); color: var(--ink); }

.form-success {
    display: none;
    background: #e8f7f2;
    border: 1px solid #b3e0d0;
    border-radius: 8px;
    padding: 14px 18px;
    color: var(--success);
    font-size: 15px;
    margin-top: 16px;
}
.form-success.show { display: block; }

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

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 48px;
}

.footer-brand { font-size: 16px; font-weight: 600; color: var(--ink); margin-bottom: 12px; }
.footer-brand span { color: var(--primary); }
.footer-desc { font-size: 14px; color: var(--body-color); line-height: 1.6; max-width: 240px; }

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

.footer-links { list-style: none; }
.footer-links li { margin-bottom: 8px; }
.footer-links a { font-size: 14px; color: var(--body-color); }
.footer-links a:hover { color: var(--ink); }

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 24px;
    border-top: 1px solid var(--hairline);
    font-size: 13px;
    color: var(--muted);
    flex-wrap: wrap;
    gap: 12px;
}

.cookie-banner {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--ink);
    color: var(--canvas);
    padding: 16px 24px;
    z-index: 200;
    display: none;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.cookie-inner {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 24px;
    flex-wrap: wrap;
    justify-content: space-between;
}

.cookie-text { font-size: 14px; color: var(--canvas-soft); line-height: 1.5; flex: 1; min-width: 200px; }
.cookie-text a { color: var(--canvas); text-decoration: underline; }

.cookie-actions { display: flex; gap: 10px; flex-shrink: 0; }

.btn-cookie-accept {
    height: 36px;
    padding: 8px 16px;
    font-size: 13px;
    font-weight: 500;
    color: var(--on-primary);
    background: var(--primary);
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-family: inherit;
}
.btn-cookie-accept:hover { background: var(--primary-active); }

.btn-cookie-reject {
    height: 36px;
    padding: 8px 16px;
    font-size: 13px;
    font-weight: 500;
    color: var(--canvas);
    background: transparent;
    border: 1px solid rgba(255,255,255,0.3);
    border-radius: 6px;
    cursor: pointer;
    font-family: inherit;
}
.btn-cookie-reject:hover { border-color: var(--canvas); }

.breadcrumb {
    display: flex;
    gap: 8px;
    font-size: 13px;
    color: var(--muted);
    margin-bottom: 16px;
    flex-wrap: wrap;
}
.breadcrumb a { color: var(--muted); }
.breadcrumb a:hover { color: var(--ink); }
.breadcrumb span { color: var(--muted-soft); }

.updated-date {
    font-size: 13px;
    color: var(--muted);
    margin-top: 8px;
}

.feature-strip {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0;
    border: 1px solid var(--hairline);
    border-radius: 12px;
    overflow: hidden;
    background: var(--surface-card);
}

.feature-strip-item {
    padding: 28px 24px;
    border-right: 1px solid var(--hairline);
}

.feature-strip-item:last-child { border-right: none; }

.feature-strip-icon {
    font-size: 22px;
    margin-bottom: 12px;
}

.feature-strip-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--ink);
    margin-bottom: 6px;
}

.feature-strip-text { font-size: 14px; color: var(--body-color); line-height: 1.5; }

.articles-feed { border-top: 1px solid var(--hairline); }

.article-row {
    display: grid;
    grid-template-columns: 240px 1fr;
    gap: 24px;
    padding: 28px 0;
    border-bottom: 1px solid var(--hairline-soft);
    align-items: start;
}

.article-row-img {
    width: 100%;
    height: 150px;
    object-fit: cover;
    border-radius: 8px;
}

.article-row-label {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.88px;
    text-transform: uppercase;
    color: var(--muted);
    margin-bottom: 6px;
}

.article-row-title {
    font-size: 20px;
    font-weight: 400;
    letter-spacing: -0.11px;
    color: var(--ink);
    margin-bottom: 8px;
    line-height: 1.3;
}

.article-row-title a { color: var(--ink); }
.article-row-title a:hover { color: var(--primary); }

.article-row-excerpt { font-size: 14px; color: var(--body-color); line-height: 1.5; margin-bottom: 10px; }
.article-row-meta { font-size: 13px; color: var(--muted); }

.loading-spinner {
    display: inline-block;
    width: 16px;
    height: 16px;
    border: 2px solid rgba(255,255,255,0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.7s linear infinite;
    margin-right: 8px;
    vertical-align: middle;
}

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

@media (max-width: 1024px) {
    .grid-3 { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
    .article-layout { grid-template-columns: 1fr; }
    .article-sidebar { position: static; }
}

@media (max-width: 768px) {
    .hero h1 { font-size: 36px; letter-spacing: -1px; }
    .section-title { font-size: 26px; }
    .nav-links { display: none; flex-direction: column; position: absolute; top: 64px; left: 0; right: 0; background: var(--canvas); border-bottom: 1px solid var(--hairline); padding: 16px 24px; gap: 0; }
    .nav-links.open { display: flex; }
    .nav-links li { border-bottom: 1px solid var(--hairline-soft); }
    .nav-links li:last-child { border-bottom: none; }
    .nav-links a { display: block; padding: 12px 0; }
    .nav-hamburger { display: flex; }
    .feature-strip { grid-template-columns: 1fr; }
    .feature-strip-item { border-right: none; border-bottom: 1px solid var(--hairline); }
    .feature-strip-item:last-child { border-bottom: none; }
    .article-row { grid-template-columns: 1fr; }
    .article-row-img { height: 200px; }
    .footer-grid { grid-template-columns: 1fr; gap: 24px; }
}

@media (max-width: 640px) {
    .grid-3, .grid-2 { grid-template-columns: 1fr; }
    .hero { padding: 48px 0; }
    .section { padding: 48px 0; }
    .article-hero h1 { font-size: 28px; }
    .page-hero h1 { font-size: 28px; }
}