:root {
    --color-primary: #18181B;
    --color-on-primary: #FFFFFF;
    --color-secondary: #3F3F46;
    --color-accent: #EC4899;
    --color-on-accent: #09090B;
    --color-link: #9D174D;
    --color-background: #FAFAFA;
    --color-foreground: #09090B;
    --color-muted: #E8ECF0;
    --color-surface: #FFFFFF;
    --color-border: #E4E4E7;
    --color-ring: #18181B;
    --header-h: 72px;
    --font-serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Songti SC", "Noto Serif SC", "Source Han Serif SC", PMingLiU, SimSun, serif;
    --font-sans: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 24px;
    --space-6: 32px;
    --space-7: 48px;
    --space-8: 64px;
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    color-scheme: light;
}

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

html {
    scroll-behavior: smooth;
}

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

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

a {
    color: var(--color-link);
    text-decoration-thickness: 1px;
    text-underline-offset: 0.18em;
    cursor: pointer;
    transition: color 200ms var(--ease-out);
}

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

:focus-visible {
    outline: 2px solid var(--color-ring);
    outline-offset: 3px;
}

.skip-link {
    position: absolute;
    left: 16px;
    top: 8px;
    z-index: 20;
    transform: translateY(-140%);
    background: var(--color-primary);
    color: var(--color-on-primary);
    padding: 8px 12px;
    text-decoration: none;
}

.skip-link:focus {
    transform: none;
}

.wrap {
    width: min(1120px, calc(100% - 32px));
    margin-inline: auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 10;
    height: var(--header-h);
    background: rgba(250, 250, 250, 0.92);
    border-bottom: 1px solid var(--color-border);
    backdrop-filter: blur(10px);
}

.nav {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.brand {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    color: var(--color-foreground);
    font-family: var(--font-serif);
    font-size: 1.25rem;
    font-weight: 650;
    letter-spacing: -0.02em;
    text-decoration: none;
}

.nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    color: var(--color-foreground);
    cursor: pointer;
}

.nav-panel {
    display: none;
    position: absolute;
    left: 0;
    right: 0;
    top: var(--header-h);
    padding: 8px 16px 16px;
    background: var(--color-background);
    border-bottom: 1px solid var(--color-border);
}

.nav-panel.is-open {
    display: grid;
    gap: 4px;
}

.nav-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
}

.nav-list a {
    display: flex;
    align-items: center;
    min-height: 44px;
    color: var(--color-secondary);
    text-decoration: none;
}

.nav-list a[aria-current="page"],
.nav-list a.is-active {
    color: var(--color-foreground);
    font-weight: 650;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 44px;
    padding: 0 18px;
    border: 1px solid transparent;
    background: transparent;
    color: var(--color-foreground);
    font: inherit;
    font-weight: 650;
    line-height: 1;
    text-decoration: none;
    cursor: pointer;
    transition: background-color 200ms var(--ease-out), color 200ms var(--ease-out), border-color 200ms var(--ease-out);
}

.btn-cta {
    min-height: 48px;
    padding: 0 28px;
    background: var(--color-accent);
    color: var(--color-on-accent);
}

.btn-cta:hover {
    background: #F472B6;
    color: var(--color-on-accent);
}

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

.btn-primary:hover {
    background: #27272A;
    color: var(--color-on-primary);
}

.btn-ghost {
    border-color: var(--color-border);
    background: var(--color-surface);
    color: var(--color-foreground);
}

.btn-ghost:hover {
    border-color: var(--color-primary);
    color: var(--color-foreground);
}

.nav-tools {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-left: auto;
}

.nav-cta {
    min-height: 44px;
    padding: 0 14px;
}

.hero {
    min-height: calc(100svh - var(--header-h));
    display: flex;
    align-items: center;
    padding: 64px 0;
    background:
        linear-gradient(to right, transparent 0, transparent calc(100% - 1px), var(--color-border) calc(100% - 1px)),
        var(--color-background);
    border-bottom: 1px solid var(--color-border);
}

.hero-grid {
    display: grid;
    gap: 40px;
    width: 100%;
}

.kicker {
    margin: 0 0 16px;
    color: var(--color-accent);
    font-size: 0.8125rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
}

.hero h1,
.page-title h1,
.article-title {
    margin: 0;
    font-family: var(--font-serif);
    font-weight: 650;
    letter-spacing: -0.03em;
    line-height: 1.15;
    color: var(--color-foreground);
}

.hero h1 {
    font-size: clamp(2.5rem, 7vw, 4.75rem);
    max-width: 12ch;
}

.hero-lead {
    max-width: 38rem;
    margin: 20px 0 0;
    color: var(--color-secondary);
    font-size: 1.0625rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

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

.hero-card {
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    gap: 16px;
    min-height: 240px;
    padding: 28px;
    background: var(--color-primary);
    color: var(--color-on-primary);
    text-decoration: none;
}

.hero-card:hover {
    background: #27272A;
    color: var(--color-on-primary);
}

.hero-card strong {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 650;
    letter-spacing: -0.03em;
    line-height: 1.1;
}

.hero-card span:last-child {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.hero-compact {
    min-height: 0;
    padding: 24px 0;
    background: var(--color-surface);
}

.hero-band {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 16px 24px;
}

.hero-band .kicker {
    margin-bottom: 8px;
}

.hero-band-title {
    margin: 0;
    max-width: 36rem;
    font-family: var(--font-serif);
    font-size: clamp(1.35rem, 2.4vw, 1.75rem);
    font-weight: 650;
    letter-spacing: -0.02em;
    line-height: 1.3;
    color: var(--color-foreground);
}

.hero-band .btn-cta {
    flex: 0 0 auto;
}

.crumbs {
    padding-top: 20px;
}

.crumbs ol {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    list-style: none;
    margin: 0;
    padding: 0;
    color: var(--color-secondary);
    font-size: 0.875rem;
}

.crumbs li + li::before {
    content: "/";
    margin-right: 8px;
}

.crumbs a {
    color: var(--color-secondary);
    text-decoration: none;
}

.layout {
    display: grid;
    gap: 32px;
    padding: 40px 0 72px;
}

.stack {
    display: grid;
    gap: 16px;
}

.card-grid {
    display: grid;
    gap: 16px;
}

.card,
.panel,
.empty {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: 20px;
}

.card h2,
.card h3,
.panel h2 {
    margin: 0 0 8px;
    font-family: var(--font-serif);
    font-size: 1.25rem;
    line-height: 1.35;
    letter-spacing: -0.02em;
}

.card h2 a,
.card h3 a,
.related a,
.panel a {
    color: var(--color-foreground);
    text-decoration: none;
}

.card h2 a:hover,
.card h3 a:hover,
.related a:hover,
.panel a:hover {
    color: var(--color-link);
}

.meta {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 14px;
    margin: 0 0 10px;
    color: var(--color-secondary);
    font-size: 0.875rem;
}

.meta a {
    color: var(--color-secondary);
    text-decoration: none;
}

.excerpt {
    margin: 0 0 14px;
    color: var(--color-secondary);
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 14px;
}

.tag {
    display: inline-flex;
    align-items: center;
    min-height: 32px;
    padding: 0 10px;
    border: 1px solid var(--color-border);
    background: var(--color-background);
    color: var(--color-secondary);
    font-size: 0.8125rem;
    text-decoration: none;
}

.tag:hover,
.tag.is-current {
    border-color: var(--color-primary);
    color: var(--color-foreground);
}

.page-title {
    margin-bottom: 8px;
}

.page-title h1 {
    font-size: clamp(2rem, 4vw, 3rem);
}

.page-title p {
    margin: 12px 0 0;
    color: var(--color-secondary);
    max-width: 42rem;
}

.panel h2 {
    font-size: 1rem;
    margin-bottom: 12px;
}

.panel ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.panel li + li {
    margin-top: 10px;
}

.panel p {
    margin: 0 0 8px;
}

.empty h2 {
    margin: 0 0 8px;
    font-family: var(--font-serif);
}

.empty p {
    margin: 0;
    color: var(--color-secondary);
}

.article-title {
    font-size: clamp(1.875rem, 4vw, 3rem);
}

.prose {
    margin-top: 28px;
    color: var(--color-foreground);
}

.prose h2,
.prose h3,
.prose h4 {
    font-family: var(--font-serif);
    line-height: 1.3;
    letter-spacing: -0.02em;
}

.prose p,
.prose li {
    color: var(--color-secondary);
}

.prose a {
    color: var(--color-link);
}

.prose img {
    display: block;
    margin: 16px 0;
}

.share {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
    margin-top: 28px;
    padding-top: 20px;
    border-top: 1px solid var(--color-border);
}

.related {
    display: grid;
    gap: 12px;
}

.error-code {
    margin: 0;
    font-family: var(--font-serif);
    font-size: clamp(4rem, 12vw, 7rem);
    line-height: 0.9;
    letter-spacing: -0.04em;
}

.pagination {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
    list-style: none;
    margin: 8px 0 0;
    padding: 0;
}

.page-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 44px;
    min-height: 44px;
    padding: 0 12px;
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    color: var(--color-foreground);
    text-decoration: none;
}

.page-item.active .page-link {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-on-primary);
}

.site-footer {
    border-top: 1px solid var(--color-border);
    padding: 48px 0 32px;
    background: var(--color-surface);
}

.footer-grid {
    display: grid;
    gap: 28px;
}

.site-footer h2,
.site-footer h3 {
    margin: 0 0 10px;
    font-family: var(--font-serif);
    font-size: 1rem;
}

.site-footer p,
.site-footer li {
    color: var(--color-secondary);
}

.site-footer ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.site-footer li + li {
    margin-top: 8px;
}

.site-footer a {
    color: var(--color-secondary);
    text-decoration: none;
}

.legal {
    margin: 28px 0 0;
    padding-top: 16px;
    border-top: 1px solid var(--color-border);
    color: var(--color-secondary);
    font-size: 0.875rem;
}

@media (max-width: 767px) {
    .hero-band .btn-cta {
        width: 100%;
    }
}

@media (min-width: 768px) {
    .wrap {
        width: min(1120px, calc(100% - 48px));
    }

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

    .footer-grid {
        grid-template-columns: 1.4fr 0.8fr 1fr;
    }
}

@media (min-width: 1024px) {
    .wrap {
        width: min(1120px, calc(100% - 64px));
    }

    .nav-toggle {
        display: none;
    }

    .nav-panel {
        display: flex;
        position: static;
        align-items: center;
        gap: 20px;
        padding: 0;
        border: 0;
        background: transparent;
    }

    .nav-list {
        display: flex;
        gap: 4px;
    }

    .nav-list a {
        padding: 0 10px;
    }

    .nav-panel {
        margin-left: auto;
    }

    .nav-tools {
        margin-left: 20px;
    }

    .hero-grid,
    .layout {
        grid-template-columns: minmax(0, 1.7fr) minmax(240px, 0.8fr);
        align-items: center;
    }

    .layout {
        align-items: start;
        gap: 48px;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation: none !important;
        transition: none !important;
    }
}