/* ============================================================
   马哥的技术收藏 · Linear 风深色样式（2026-08-18 重构）
   设计 token（DESIGN.md 风格）：
   - bg:      #0F1115 (base) / #171A21 (surface) / #1E2128 (elevated)
   - border:  #262932 → hover #3B3F4A
   - text:    #E8E9EB / #9CA0A8 / #5C6068
   - accent:  #3B82F6 (only on hover/active/link/focus)
   - radius:  8px / 10px / 14px
   - font:    系统 sans, tabular-nums
   - icon:    Lucide 1.5 stroke
   ============================================================ */

/* ----------- design tokens ----------- */
:root {
    --bg-base:       #0F1115;
    --bg-surface:    #171A21;
    --bg-elevated:   #1E2128;
    --bg-overlay:    rgba(15, 17, 21, 0.72);

    --border:        #262932;
    --border-strong: #3B3F4A;

    --text-primary:   #E8E9EB;
    --text-secondary: #9CA0A8;
    --text-tertiary:  #5C6068;

    --accent:        #3B82F6;
    --accent-soft:   rgba(59, 130, 246, 0.12);
    --accent-glow:   rgba(59, 130, 246, 0.35);

    --shadow-sm:     0 1px 2px rgba(0, 0, 0, .4);
    --shadow-md:     0 1px 2px rgba(0, 0, 0, .4), 0 8px 24px rgba(0, 0, 0, .3);
    --shadow-lg:     0 1px 3px rgba(0, 0, 0, .5), 0 16px 48px rgba(0, 0, 0, .4);

    --radius-sm: 8px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;

    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
                 "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo,
                 "Cascadia Code", "Roboto Mono", Consolas, monospace;

    --max-w: 1200px;
    --nav-h: 56px;

    color-scheme: dark;
}

/* ----------- reset & base ----------- */
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html {
    font-family: var(--font-sans);
    font-size: 15px;
    line-height: 1.55;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
    font-feature-settings: "ss01", "cv11";
}
body {
    background: var(--bg-base);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}
.page { display: flex; flex-direction: column; min-height: 100vh; }

a { color: inherit; text-decoration: none; transition: color .15s ease; }
a:hover { color: var(--accent); }
code { font-family: var(--font-mono); font-size: 0.92em; }
.num { font-variant-numeric: tabular-nums; font-feature-settings: "tnum"; }
.text-muted { color: var(--text-tertiary); }

::selection { background: var(--accent-glow); color: var(--text-primary); }

/* scrollbar (webkit) */
::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: var(--bg-base); }
::-webkit-scrollbar-thumb {
    background: var(--border-strong);
    border-radius: 6px;
    border: 2px solid var(--bg-base);
}
::-webkit-scrollbar-thumb:hover { background: #4d5260; }

/* ============================================================
   顶栏 nav
   ============================================================ */
.site-nav {
    position: sticky;
    top: 0;
    z-index: 50;
    height: var(--nav-h);
    background: rgba(15, 17, 21, 0.55);
    backdrop-filter: saturate(180%) blur(16px) brightness(110%);
    -webkit-backdrop-filter: saturate(180%) blur(16px) brightness(110%);
    border-bottom: 1px solid var(--border);
}
.site-nav__inner {
    max-width: var(--max-w);
    height: 100%;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    gap: 32px;
}
.site-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-primary);
}
.site-brand__logo { display: inline-flex; }
.site-brand__logo .mascot { display: block; }
.site-brand__text { display: flex; flex-direction: column; line-height: 1.2; }
.site-brand__name {
    font-size: 14px;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--text-primary);
}
.site-brand__tag {
    font-size: 11px;
    color: var(--text-tertiary);
    font-family: var(--font-mono);
}

.site-nav__links {
    margin-left: auto;
    display: flex;
    gap: 4px;
}
.nav-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 7px 12px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: background .15s, color .15s;
}
.nav-link:hover {
    background: var(--bg-elevated);
    color: var(--text-primary);
}
.nav-link--active {
    background: var(--bg-elevated);
    color: var(--text-primary);
}
.nav-link--active .nav-link__icon { color: var(--accent); }
.nav-link__icon { display: inline-flex; color: var(--text-tertiary); }

@media (max-width: 720px) {
    .site-brand__text { display: none; }
    .nav-link__label { display: none; }
}

/* ============================================================
   main & footer
   ============================================================ */
.page__main {
    flex: 1;
    width: 100%;
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 48px 24px 96px;
}

.site-footer {
    border-top: 1px solid var(--border);
    padding: 48px 24px 56px;
    margin-top: 64px;
    background: var(--bg-base);
}
.site-footer__inner {
    max-width: var(--max-w);
    margin: 0 auto;
    display: flex;
    gap: 32px;
    align-items: flex-start;
    justify-content: space-between;
    flex-wrap: wrap;
}
.site-footer__brand { display: flex; align-items: center; gap: 12px; }
.site-footer__name { font-size: 14px; font-weight: 600; color: var(--text-primary); }
.site-footer__tag  { font-size: 12px; color: var(--text-tertiary); font-family: var(--font-mono); }
.site-footer__meta { max-width: 480px; }
.site-footer__meta p { margin: 0 0 6px; font-size: 13px; color: var(--text-secondary); }
.site-footer__disclaimer { color: var(--text-tertiary); font-size: 12px !important; }

.link { color: var(--accent); }
.link:hover { text-decoration: underline; text-underline-offset: 3px; }
.code-inline {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 1px 6px;
    font-size: 12px;
    color: var(--text-secondary);
}

/* ============================================================
   页面大标题
   ============================================================ */
.page-heading {
    text-align: center;
    margin: 0 auto 56px;
    max-width: 720px;
}
.kicker {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    border-radius: 999px;
    background: var(--accent-soft);
    border: 1px solid rgba(59, 130, 246, 0.25);
    font-size: 12px;
    color: var(--accent);
    margin-bottom: 18px;
    font-weight: 500;
}
.kicker__dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 8px var(--accent-glow);
    animation: pulse 2.4s ease-in-out infinite;
}
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}
.page-heading__row {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 14px;
    margin-bottom: 16px;
}
.page-heading__icon {
    display: inline-flex;
    color: var(--accent);
}
.page-heading__title {
    margin: 0;
    font-size: clamp(36px, 5vw, 52px);
    font-weight: 700;
    letter-spacing: -0.025em;
    line-height: 1.1;
    background: linear-gradient(180deg, #FFFFFF 0%, #9CA0A8 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.page-heading__sub {
    margin: 12px auto 0;
    font-size: 17px;
    color: var(--text-secondary);
    max-width: 560px;
    line-height: 1.55;
}

/* ============================================================
   项目卡片（grid）
   ============================================================ */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
    gap: 16px;
}
.card {
    display: flex;
    flex-direction: column;
    padding: 20px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    transition: border-color .15s, background .15s, transform .15s;
    color: inherit;
    position: relative;
    overflow: hidden;
}
.card::before {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: linear-gradient(180deg, var(--accent-soft) 0%, transparent 60%);
    opacity: 0;
    transition: opacity .2s;
    pointer-events: none;
}
.card:hover {
    border-color: var(--border-strong);
    background: var(--bg-elevated);
}
.card:hover::before { opacity: 1; }
.card > * { position: relative; }

.card__head {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: 14px;
}
.card__icon {
    width: 36px; height: 36px;
    border-radius: var(--radius-sm);
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    display: grid;
    place-items: center;
    color: var(--cat, var(--text-secondary));
}
.card:hover .card__icon {
    border-color: color-mix(in srgb, var(--cat, var(--text-secondary)) 35%, transparent);
}
.card__meta {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 2px;
    font-size: 12px;
    color: var(--text-tertiary);
}
.card__stars {
    display: inline-flex; align-items: center; gap: 3px;
}
.card__stars svg { color: var(--text-tertiary); }
.card__lang { font-family: var(--font-mono); font-size: 11px; }

.card__title {
    margin: 0 0 8px;
    font-size: 16px;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--text-primary);
}
.card__desc {
    margin: 0;
    font-size: 13px;
    line-height: 1.55;
    color: var(--text-secondary);
    flex: 1;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.card__foot {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-top: 16px;
    padding-top: 14px;
    border-top: 1px solid var(--border);
}
.card__arrow {
    display: inline-flex;
    color: var(--text-tertiary);
    transition: color .15s, transform .15s;
}
.card:hover .card__arrow { color: var(--accent); transform: translateX(2px); }

.badge {
    display: inline-flex;
    align-items: center;
    padding: 3px 9px;
    border-radius: 999px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    font-size: 11px;
    font-weight: 500;
    color: var(--text-secondary);
    letter-spacing: 0.01em;
}

/* ============================================================
   首页 hero & stats
   ============================================================ */
.hero {
    text-align: center;
    padding: 24px 0 48px;
    margin-bottom: 56px;
}
.hero__mascots {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 32px;
}
.hero__mascots .mascot {
    filter: drop-shadow(0 8px 24px rgba(0, 0, 0, .4));
    transition: transform .3s cubic-bezier(.2,.8,.2,1);
}
.hero__mascots .mascot:nth-child(1) { animation: bob 4.2s ease-in-out infinite; }
.hero__mascots .mascot:nth-child(2) { animation: bob 4.2s ease-in-out -1.4s infinite; }
.hero__mascots .mascot:nth-child(3) { animation: bob 4.2s ease-in-out -2.8s infinite; }
@keyframes bob {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-6px); }
}
.hero__title {
    margin: 0 0 16px;
    font-size: clamp(40px, 6vw, 64px);
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.05;
    background: linear-gradient(180deg, #FFFFFF 0%, #9CA0A8 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero__sub {
    margin: 0 auto;
    max-width: 540px;
    font-size: 17px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* stats 卡片组 */
.stats-row {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    max-width: 720px;
    margin: 40px auto 0;
}
.stat-card {
    padding: 20px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    text-align: center;
}
.stat-card__value {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
    font-feature-settings: "tnum";
}
.stat-card__label {
    margin-top: 4px;
    font-size: 12px;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}
@media (max-width: 560px) {
    .stats-row { grid-template-columns: 1fr; }
}

/* ============================================================
   搜索框
   ============================================================ */
.search-wrap {
    max-width: 560px;
    margin: 0 auto 40px;
}
.search-input {
    width: 100%;
    height: 44px;
    padding: 0 16px 0 44px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 14px;
    transition: border-color .15s, background .15s;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%239CA0A8' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='11' cy='11' r='8'/%3E%3Cpath d='m21 21-4.3-4.3'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: 16px center;
}
.search-input::placeholder { color: var(--text-tertiary); }
.search-input:focus {
    outline: none;
    border-color: var(--accent);
    background-color: var(--bg-elevated);
    box-shadow: 0 0 0 3px var(--accent-soft);
}

/* ============================================================
   Section header (分类分组标题)
   ============================================================ */
.section-header {
    display: flex;
    align-items: baseline;
    justify-content: space-between;
    margin: 56px 0 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
}
.section-header__title {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 0;
    font-size: 18px;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--text-primary);
}
.section-header__title-icon {
    display: inline-flex;
    color: var(--accent);
}
.section-header__count {
    font-size: 12px;
    color: var(--text-tertiary);
    font-variant-numeric: tabular-nums;
    font-family: var(--font-mono);
}

/* ============================================================
   项目详情页
   ============================================================ */
.detail {
    max-width: 820px;
    margin: 0 auto;
}
.detail__head {
    margin-bottom: 32px;
}
.detail__back {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: 24px;
}
.detail__title {
    margin: 0 0 12px;
    font-size: 36px;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.15;
}
.detail__desc {
    margin: 0 0 20px;
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.6;
}
.detail__meta {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    align-items: center;
}
.detail__meta-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    background: var(--bg-surface);
    border: 1px solid var(--border);
    font-size: 13px;
    color: var(--text-secondary);
    transition: all .15s;
}
.detail__meta-link:hover {
    border-color: var(--accent);
    color: var(--accent);
}

.detail-section {
    margin-top: 48px;
    padding-top: 32px;
    border-top: 1px solid var(--border);
}
.detail-section__title {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 0 0 20px;
    font-size: 15px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-tertiary);
}
.detail-section__title-icon { color: var(--accent); display: inline-flex; }

/* use_case 列表 */
.uc-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.uc-list li {
    display: flex;
    gap: 14px;
    padding: 14px 16px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
}
.uc-num {
    flex-shrink: 0;
    width: 24px;
    height: 24px;
    display: grid;
    place-items: center;
    border-radius: 6px;
    background: var(--accent-soft);
    color: var(--accent);
    font-size: 12px;
    font-weight: 600;
    font-variant-numeric: tabular-nums;
}
.uc-text {
    flex: 1;
    line-height: 1.6;
    color: var(--text-primary);
}

/* tags row */
.tag-row { display: flex; flex-wrap: wrap; gap: 6px; }
.tag {
    display: inline-flex;
    padding: 3px 9px;
    border-radius: 999px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    font-size: 12px;
    color: var(--text-secondary);
    font-family: var(--font-mono);
}

/* demo iframe 容器 */
.demo-frame {
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--bg-surface);
    box-shadow: var(--shadow-md);
}
.demo-frame__head {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 16px;
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border);
}
.demo-window-dots { display: flex; gap: 6px; }
.demo-window-dots span {
    display: inline-block;
    width: 12px; height: 12px;
    border-radius: 50%;
}
.demo-window-dots span:nth-child(1) { background: #FF5F57; }
.demo-window-dots span:nth-child(2) { background: #FEBC2E; }
.demo-window-dots span:nth-child(3) { background: #28C840; }
.demo-frame__url {
    flex: 1;
    font-family: var(--font-mono);
    font-size: 12px;
    color: var(--text-tertiary);
}
.demo-frame__body {
    width: 100%;
    aspect-ratio: 16 / 10;
    border: none;
    background: var(--bg-base);
}

/* ============================================================
   Empty state
   ============================================================ */
.empty-state {
    text-align: center;
    padding: 80px 24px;
    color: var(--text-tertiary);
}
.empty-state__icon { display: inline-flex; color: var(--text-tertiary); margin-bottom: 12px; }

/* ============================================================
   分类索引页（grid of cards，每个分类一个 cell）
   ============================================================ */
.cat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 12px;
}
.cat-cell {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px;
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    transition: border-color .15s, background .15s;
}
.cat-cell:hover { border-color: var(--border-strong); background: var(--bg-elevated); }
.cat-cell__icon {
    width: 36px; height: 36px;
    border-radius: var(--radius-sm);
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    display: grid;
    place-items: center;
    flex-shrink: 0;
    color: var(--cat, var(--text-secondary));
}
.cat-cell__body { flex: 1; min-width: 0; }
.cat-cell__name {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 2px;
}
.cat-cell__count {
    font-size: 12px;
    color: var(--text-tertiary);
    font-variant-numeric: tabular-nums;
}

/* ============================================================
   About page
   ============================================================ */
.prose {
    max-width: 640px;
    margin: 0 auto;
    color: var(--text-secondary);
    line-height: 1.75;
    font-size: 15px;
}
.prose h2 {
    color: var(--text-primary);
    font-size: 18px;
    font-weight: 600;
    margin: 40px 0 12px;
    letter-spacing: -0.01em;
}
.prose p { margin: 0 0 16px; }
.prose ul { padding-left: 20px; }
.prose li { margin-bottom: 6px; }