/* ============================================================
   FunctionCool / Skill — Design System v3
   Editorial · Engineering Handbook · Magazine-meets-documentation
   ============================================================ */

:root {
    /* —— Color tokens ——
       Restrained. Sky is the single brand accent.
       Gold is reserved for Skill identity moments. No purple, no neon. */
    --ink:        #15324C;
    --ink-2:      #51677C;
    --ink-3:      #8395A6;
    --ink-4:      #B5C2D0;
    --line:       rgba(20, 58, 92, 0.10);
    --line-2:     rgba(20, 58, 92, 0.18);

    --canvas:     #F4F8FC;
    --canvas-2:   #EAF2F8;
    --surface:    #FFFFFF;
    --surface-2:  #FBFDFF;

    --sky:        #73B9E6;
    --sky-50:     #F0F7FC;
    --sky-100:    #E1EFF8;
    --sky-200:    #C5DFF0;
    --sky-300:    #9CCBEC;
    --sky-500:    #3A8DD0;
    --sky-700:    #1B4E7A;
    --sky-900:    #0E2E4A;

    --gold:       #F2B53C;
    --gold-soft:  #FFEAB0;

    --code-bg:    #0F2438;
    --code-text:  #DCEBF8;

    /* —— Spacing rhythm (4px base) —— */
    --s-1: 4px;
    --s-2: 8px;
    --s-3: 12px;
    --s-4: 16px;
    --s-5: 20px;
    --s-6: 24px;
    --s-8: 32px;
    --s-10: 40px;
    --s-12: 48px;
    --s-16: 64px;
    --s-20: 80px;
    --s-24: 96px;

    /* —— Type scale —— */
    --fs-xs: 0.75rem;
    --fs-sm: 0.875rem;
    --fs-base: 1rem;
    --fs-md: 1.0625rem;
    --fs-lg: 1.25rem;
    --fs-xl: 1.5rem;
    --fs-2xl: clamp(1.625rem, 2.4vw, 2rem);
    --fs-3xl: clamp(2rem, 3.6vw, 2.75rem);
    --fs-4xl: clamp(2.25rem, 5.2vw, 3.75rem);

    /* —— Radii —— */
    --r-xs: 4px;
    --r-sm: 6px;
    --r-md: 10px;
    --r-lg: 16px;
    --r-xl: 24px;
    --r-pill: 999px;

    /* —— Motion —— */
    --ease:     cubic-bezier(0.22, 1, 0.36, 1);
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --t-fast: 0.15s;
    --t: 0.25s;
    --t-slow: 0.45s;
}

/* ============================================================
   Base reset
   ============================================================ */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "Helvetica Neue",
                 "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "WenQuanYi Micro Hei",
                 sans-serif;
    font-size: var(--fs-base);
    line-height: 1.65;
    color: var(--ink);
    background: var(--canvas);
    font-feature-settings: "kern" 1, "liga" 1, "calt" 1;
    -webkit-tap-highlight-color: transparent;
    min-height: 100vh;
    overflow-x: hidden;
}

img, svg { max-width: 100%; display: block; }

a { color: var(--sky-700); }

::selection { background: var(--sky-200); color: var(--sky-900); }

@media (pointer: fine) {
    ::-webkit-scrollbar { width: 10px; height: 10px; }
    ::-webkit-scrollbar-track { background: transparent; }
    ::-webkit-scrollbar-thumb {
        background: var(--ink-4);
        border-radius: var(--r-pill);
        border: 2px solid var(--canvas);
    }
    ::-webkit-scrollbar-thumb:hover { background: var(--ink-3); }
}

/* ============================================================
   Layout
   ============================================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 clamp(20px, 4vw, 32px);
}

main {
    padding: clamp(48px, 6vw, 80px) 0 clamp(64px, 8vw, 96px);
}

/* Editorial kicker (small all-caps label above titles) */
.kicker {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    font-size: var(--fs-xs);
    font-weight: 600;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--sky-700);
    margin-bottom: var(--s-4);
}
.kicker::before {
    content: "";
    width: 24px;
    height: 1px;
    background: var(--sky-500);
}

/* Section header (eyebrow + heading) */
.section-head {
    margin-bottom: var(--s-10);
}
.section-head.centred { text-align: center; }
.section-head.centred .eyebrow { justify-content: center; }

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    font-size: var(--fs-xs);
    font-weight: 600;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--sky-700);
    margin-bottom: var(--s-3);
}
.eyebrow .num {
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
    color: var(--sky-500);
    font-weight: 500;
    font-variant-numeric: tabular-nums;
}
.eyebrow::after {
    content: "";
    width: 24px;
    height: 1px;
    background: var(--line-2);
}

.section-head h2,
.latest-posts > h2 {
    font-size: var(--fs-3xl);
    font-weight: 700;
    letter-spacing: -0.025em;
    line-height: 1.15;
    color: var(--ink);
}
.latest-posts > h2 { text-align: center; margin-bottom: var(--s-10); }

/* ============================================================
   Header — clean editorial bar
   ============================================================ */
header {
    background: var(--surface);
    border-bottom: 1px solid var(--line);
    padding: var(--s-4) 0;
    position: relative;
}

header::after {
    content: "";
    position: absolute;
    left: 0; right: 0; bottom: -1px;
    height: 2px;
    background: var(--sky);
    opacity: 0.6;
}

header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--s-6);
}

.logo h1 {
    font-size: var(--fs-xl);
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.1;
    color: var(--ink);
}
.logo h1 a {
    color: inherit;
    text-decoration: none;
    transition: color var(--t) var(--ease);
}
.logo h1 a:hover { color: var(--sky-700); }
.logo p {
    font-size: var(--fs-sm);
    color: var(--ink-2);
    margin-top: 2px;
}

.language-switcher {
    display: flex;
    align-items: center;
    gap: var(--s-2);
}
.language-switcher a,
.language-switcher button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--s-2) var(--s-4);
    font-size: var(--fs-sm);
    font-weight: 500;
    color: var(--ink-2);
    background: transparent;
    border: 1px solid var(--line-2);
    border-radius: var(--r-pill);
    cursor: pointer;
    text-decoration: none;
    line-height: 1;
    transition: color var(--t) var(--ease),
                border-color var(--t) var(--ease),
                background var(--t) var(--ease);
}
.language-switcher a:hover,
.language-switcher button:hover {
    color: var(--sky-700);
    border-color: var(--sky-300);
    background: var(--sky-50);
}
.skill-link {
    color: var(--sky-700);
    border-color: var(--sky-300);
    font-weight: 600;
}
.skill-link:hover {
    color: var(--surface);
    background: var(--sky-700);
    border-color: var(--sky-700);
}

/* ============================================================
   Hero / search section — editorial composition
   ============================================================ */
.search-section {
    position: relative;
    background: linear-gradient(180deg, var(--surface) 0%, var(--canvas) 100%);
    border: 1px solid var(--line);
    border-radius: var(--r-lg);
    padding: clamp(56px, 8vw, 96px) clamp(24px, 5vw, 56px);
    margin-top: var(--s-10);
    margin-bottom: var(--s-20);
    overflow: hidden;
    text-align: center;
}
.search-section::before {
    content: "";
    position: absolute;
    inset: 0;
    background-image: radial-gradient(circle at 1px 1px, var(--line) 1px, transparent 0);
    background-size: 28px 28px;
    -webkit-mask-image: radial-gradient(ellipse 70% 70% at 50% 40%, #000, transparent 80%);
    mask-image: radial-gradient(ellipse 70% 70% at 50% 40%, #000, transparent 80%);
    pointer-events: none;
    opacity: 0.6;
}
.search-section::after {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(28rem 28rem at 100% 0%, rgba(115,185,230,0.10), transparent 60%),
        radial-gradient(22rem 22rem at 0% 100%, rgba(242,181,60,0.08), transparent 60%);
    pointer-events: none;
}
.search-section > * { position: relative; z-index: 1; }

.search-section h2 {
    font-size: var(--fs-4xl);
    font-weight: 700;
    letter-spacing: -0.035em;
    line-height: 1.05;
    color: var(--ink);
    margin-bottom: var(--s-4);
    max-width: 18ch;
    margin-left: auto;
    margin-right: auto;
}
.search-section p {
    font-size: var(--fs-md);
    color: var(--ink-2);
    max-width: 50ch;
    margin: 0 auto var(--s-10);
}

/* —— Search form —— */
.search-form {
    max-width: 640px;
    margin: 0 auto;
}
.search-input-wrapper {
    position: relative;
    margin-bottom: var(--s-6);
}
.search-input-wrapper input {
    width: 100%;
    padding: var(--s-4) var(--s-5);
    font-size: var(--fs-md);
    font-family: inherit;
    color: var(--ink);
    background: var(--surface);
    border: 1px solid var(--line-2);
    border-radius: var(--r-md);
    outline: none;
    transition: border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}
.search-input-wrapper input::placeholder { color: var(--ink-3); }
.search-input-wrapper input:focus {
    border-color: var(--sky-500);
    box-shadow: 0 0 0 3px var(--sky-100);
}

.language-filter label {
    display: block;
    font-size: var(--fs-xs);
    font-weight: 600;
    color: var(--ink-2);
    margin-bottom: var(--s-3);
    text-align: center;
    text-transform: uppercase;
    letter-spacing: 0.12em;
}
.language-options {
    display: flex;
    flex-wrap: wrap;
    gap: var(--s-2);
    justify-content: center;
}
.lang-option {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    padding: var(--s-2) var(--s-3);
    font-size: var(--fs-sm);
    font-weight: 500;
    color: var(--ink-2);
    background: var(--surface);
    border: 1px solid var(--line-2);
    border-radius: var(--r-pill);
    cursor: pointer;
    transition: color var(--t) var(--ease),
                border-color var(--t) var(--ease),
                background var(--t) var(--ease);
}
.lang-option:hover {
    color: var(--sky-700);
    border-color: var(--sky-300);
    background: var(--sky-50);
}
.lang-option input[type="radio"] { display: none; }
.lang-option:has(input[type="radio"]:checked) {
    color: var(--sky-900);
    background: var(--sky-100);
    border-color: var(--sky-500);
    font-weight: 600;
}

.search-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin: var(--s-6) auto 0;
    padding: var(--s-3) var(--s-10);
    font-size: var(--fs-sm);
    font-weight: 600;
    font-family: inherit;
    color: var(--surface);
    background: var(--sky-700);
    border: none;
    border-radius: var(--r-pill);
    cursor: pointer;
    letter-spacing: 0.02em;
    transition: background var(--t) var(--ease),
                transform var(--t) var(--ease),
                box-shadow var(--t) var(--ease);
    box-shadow: 0 1px 0 var(--sky-900);
}
.search-btn:hover {
    background: var(--sky-900);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px -2px rgba(20, 58, 92, 0.25);
}
.search-btn:active { transform: translateY(0); }

/* ============================================================
   Section wrappers + asymmetric grids
   ============================================================ */
.features-section,
.latest-posts,
.info-section {
    margin-bottom: clamp(64px, 8vw, 96px);
}

/* Features: 4 cards, Z-pattern, AI Skill is the wide bottom-right */
.features-grid {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: var(--s-5);
}
.feature-card {
    grid-column: span 6;
    position: relative;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-6) var(--s-6) var(--s-5);
    text-decoration: none;
    color: inherit;
    display: flex;
    flex-direction: column;
    gap: var(--s-2);
    transition: transform var(--t) var(--ease),
                border-color var(--t) var(--ease),
                box-shadow var(--t) var(--ease);
}
.feature-card:hover {
    transform: translateY(-2px);
    border-color: var(--sky-300);
    box-shadow: 0 10px 30px -10px rgba(20, 58, 92, 0.15);
}
.feature-card:nth-child(1) { grid-column: 1 / span 5; }
.feature-card:nth-child(2) { grid-column: 6 / span 7; }
.feature-card:nth-child(3) { grid-column: 1 / span 4; }
.feature-card:nth-child(4) { grid-column: 5 / span 8; }
.feature-card h3 {
    font-size: var(--fs-lg);
    font-weight: 600;
    letter-spacing: -0.015em;
    color: var(--ink);
    display: flex;
    align-items: baseline;
    gap: var(--s-3);
}
.feature-card h3::before {
    content: attr(data-num);
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
    font-size: var(--fs-xs);
    color: var(--sky-500);
    font-weight: 500;
    font-variant-numeric: tabular-nums;
}
.feature-card p {
    font-size: var(--fs-sm);
    color: var(--ink-2);
    line-height: 1.6;
    max-width: 50ch;
}
/* AI Skill highlighted: gold identity, distinct surface */
a.feature-card[href="/skillapi"] {
    background: linear-gradient(135deg, #FFFCF2 0%, var(--surface) 60%);
    border-color: rgba(242, 181, 60, 0.4);
}
a.feature-card[href="/skillapi"]::after {
    content: "RECOMMENDED";
    position: absolute;
    top: var(--s-4);
    right: var(--s-5);
    font-size: 0.625rem;
    font-weight: 700;
    letter-spacing: 0.16em;
    color: var(--gold);
    font-family: ui-monospace, "SF Mono", monospace;
}
a.feature-card[href="/skillapi"]:hover {
    border-color: var(--gold);
    box-shadow: 0 12px 32px -10px rgba(242, 181, 60, 0.3);
}
a.feature-card[href="/skillapi"] h3::before { color: var(--gold); }

/* Latest posts: newest first, asymmetric */
.latest-list {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: var(--s-5);
}
.post-item {
    grid-column: span 6;
    position: relative;
    display: flex;
    flex-direction: column;
    gap: var(--s-3);
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-6);
    text-decoration: none;
    color: inherit;
    transition: transform var(--t) var(--ease),
                border-color var(--t) var(--ease),
                box-shadow var(--t) var(--ease);
}
.post-item:hover {
    transform: translateY(-2px);
    border-color: var(--sky-300);
    box-shadow: 0 10px 30px -10px rgba(20, 58, 92, 0.15);
}
.post-item:nth-child(1) { grid-column: 1 / span 7; }
.post-item:nth-child(2) { grid-column: 8 / span 5; }
.post-item:nth-child(3) { grid-column: 1 / span 12; }
.post-meta {
    display: flex;
    align-items: center;
    gap: var(--s-3);
    color: var(--ink-3);
    font-size: var(--fs-xs);
    font-variant-numeric: tabular-nums;
    text-transform: uppercase;
    letter-spacing: 0.08em;
}
.post-date { color: var(--ink-3); }
.post-tag {
    display: inline-flex;
    align-items: center;
    padding: 2px 8px;
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    color: var(--sky-700);
    background: var(--sky-50);
    border: 1px solid var(--sky-100);
    border-radius: var(--r-xs);
    text-transform: uppercase;
}
.post-title {
    font-size: var(--fs-xl);
    font-weight: 600;
    letter-spacing: -0.015em;
    color: var(--ink);
    line-height: 1.3;
    transition: color var(--t) var(--ease);
}
.post-item:hover .post-title { color: var(--sky-700); }
.post-desc {
    font-size: var(--fs-sm);
    color: var(--ink-2);
    line-height: 1.6;
    max-width: 65ch;
}

/* Info: support leads with QR */
.info-grid {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: var(--s-5);
}
.info-card {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-6);
    transition: transform var(--t) var(--ease),
                border-color var(--t) var(--ease);
}
.info-card:hover { transform: translateY(-1px); border-color: var(--line-2); }
.info-card:nth-child(1) { grid-column: 1 / span 6; }
.info-card:nth-child(2) { grid-column: 7 / span 3; }
.info-card:nth-child(3) { grid-column: 10 / span 3; }
.info-card h3 {
    font-size: var(--fs-md);
    font-weight: 600;
    color: var(--ink);
    margin-bottom: var(--s-3);
    letter-spacing: -0.005em;
}
.info-card p {
    font-size: var(--fs-sm);
    color: var(--ink-2);
    line-height: 1.65;
}
.support-content { text-align: center; }
.support-content .support-text {
    text-align: left;
    color: var(--ink-2);
    line-height: 1.65;
    font-size: var(--fs-sm);
    margin: 0 0 var(--s-4);
}
.support-qr-image {
    display: block;
    max-width: 180px;
    width: 100%;
    height: auto;
    margin: 0 auto;
    border-radius: var(--r-sm);
    border: 1px solid var(--line);
}

/* ============================================================
   Search results — compact header + reference cards
   ============================================================ */
.search-header {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-lg);
    padding: var(--s-6);
    margin-top: var(--s-6);
    margin-bottom: var(--s-8);
}

.search-form.compact {
    --h: 48px;
    --gap: var(--s-3);
    --btn-min: 140px;
    --lang-min: 168px;
    display: grid;
    grid-template-columns: minmax(0, 1fr) var(--lang-min) var(--btn-min);
    gap: var(--gap);
    align-items: stretch;
    width: 100%;
    max-width: 1080px;
    margin: 0 auto;
}
.search-form.compact .search-input-wrapper { min-width: 200px; margin-bottom: 0; }
.search-form.compact .search-input-wrapper input {
    width: 100%;
    height: var(--h);
    padding: 0 var(--s-4);
    font-size: var(--fs-sm);
    border: 1px solid var(--line-2);
    border-radius: var(--r-sm);
    background: var(--surface);
}
.search-form.compact .search-input-wrapper input:focus {
    border-color: var(--sky-500);
    box-shadow: 0 0 0 3px var(--sky-100);
}

.language-filter.inline { position: relative; }
.language-filter.inline select {
    height: var(--h);
    width: 100%;
    padding: 0 32px 0 var(--s-4);
    font-size: var(--fs-sm);
    font-family: inherit;
    color: var(--ink);
    background: var(--surface);
    border: 1px solid var(--line-2);
    border-radius: var(--r-sm);
    outline: none;
    cursor: pointer;
    appearance: none;
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M3 5l3 3 3-3' fill='none' stroke='%2351667C' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-position: right 12px center;
    background-repeat: no-repeat;
    transition: border-color var(--t) var(--ease), box-shadow var(--t) var(--ease);
}
.language-filter.inline select:focus {
    border-color: var(--sky-500);
    box-shadow: 0 0 0 3px var(--sky-100);
}

.search-form.compact .search-btn {
    height: var(--h);
    min-width: var(--btn-min);
    margin-top: 0;
    padding: 0 var(--s-6);
    border-radius: var(--r-sm);
    font-size: var(--fs-sm);
    background: var(--sky-700);
    box-shadow: none;
}
.search-form.compact .search-btn:hover {
    background: var(--sky-900);
    transform: none;
}

.results-section { margin-top: var(--s-4); }
.results-header { margin-bottom: var(--s-6); }
.results-header h2 {
    font-size: var(--fs-2xl);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--ink);
    margin-bottom: var(--s-1);
}
.results-header p {
    font-size: var(--fs-sm);
    color: var(--ink-3);
    font-variant-numeric: tabular-nums;
}

.results-grid { display: grid; gap: var(--s-5); grid-template-columns: minmax(0, 1fr); }

/* ============================================================
   Function card — engineering reference style
   ============================================================ */
.function-card {
    position: relative;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-6);
    min-width: 0;
    overflow-x: hidden;
    animation: reveal-up var(--t-slow) var(--ease-out) both;
    transition: border-color var(--t) var(--ease);
}
.function-card:hover { border-color: var(--line-2); }
.function-card + .function-card { margin-top: 0; }

.function-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--s-4);
    margin-bottom: var(--s-3);
}
.function-name-section { flex: 1; min-width: 0; }
.function-name { display: flex; align-items: center; flex-wrap: wrap; gap: var(--s-3); }
.name-wrapper h3 {
    font-size: var(--fs-xl);
    font-weight: 600;
    letter-spacing: -0.015em;
    color: var(--ink);
    line-height: 1.25;
    margin: 0;
}
.function-tags { display: flex; flex-wrap: wrap; gap: var(--s-1); }
.function-tags .tag {
    display: inline-flex;
    align-items: center;
    padding: 2px 8px;
    font-size: 0.6875rem;
    font-weight: 500;
    color: var(--ink-2);
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--r-xs);
    letter-spacing: 0.02em;
}
.function-tags .tag:hover { color: var(--sky-700); border-color: var(--sky-200); }
.language-tag {
    display: inline-flex;
    align-items: center;
    padding: 2px 10px;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    color: var(--sky-700);
    background: var(--sky-50);
    border: 1px solid var(--sky-100);
    border-radius: var(--r-xs);
    text-transform: uppercase;
    white-space: nowrap;
    flex: none;
}

.function-description {
    margin-bottom: var(--s-4);
    padding-bottom: var(--s-4);
    border-bottom: 1px solid var(--line);
}
.function-description p {
    font-size: var(--fs-sm);
    color: var(--ink-2);
    line-height: 1.65;
    max-width: 72ch;
}

.function-details {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--s-3) var(--s-6);
    margin-bottom: var(--s-4);
    padding: var(--s-4);
    background: var(--surface-2);
    border-radius: var(--r-sm);
    border: 1px solid var(--line);
}
.function-details > div { margin: 0; }
.function-details strong {
    display: block;
    color: var(--ink-3);
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    margin-bottom: var(--s-2);
}
.param, .return {
    display: inline-block;
    padding: 2px 8px;
    font-size: var(--fs-xs);
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
    color: var(--ink);
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-xs);
    margin: 0 4px 4px 0;
    font-variant-numeric: tabular-nums;
}

.scores {
    display: flex;
    gap: var(--s-8);
    margin-bottom: var(--s-4);
    padding: var(--s-3) var(--s-4);
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-sm);
}
.score { display: flex; flex-direction: column; gap: 2px; }
.score span:first-child {
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--ink-3);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}
.score-value {
    font-size: var(--fs-lg);
    font-weight: 600;
    color: var(--ink);
    font-family: ui-monospace, "SF Mono", monospace;
    font-variant-numeric: tabular-nums;
}

.code-section { border-top: 1px solid var(--line); padding-top: var(--s-4); }
.code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--s-3);
    margin-bottom: var(--s-3);
}
.toggle-code {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    padding: var(--s-2) var(--s-4);
    font-size: var(--fs-sm);
    font-weight: 500;
    color: var(--ink);
    background: var(--surface);
    border: 1px solid var(--line-2);
    border-radius: var(--r-sm);
    cursor: pointer;
    transition: color var(--t) var(--ease), border-color var(--t) var(--ease);
}
.toggle-code:hover { color: var(--sky-700); border-color: var(--sky-300); }
.toggle-code::before {
    content: "";
    width: 8px; height: 8px;
    border-right: 1.5px solid currentColor;
    border-bottom: 1.5px solid currentColor;
    transform: rotate(45deg);
    transition: transform var(--t) var(--ease);
}
.code-container:not([style*="display: none"]) + .code-section .toggle-code::before,
.toggle-code.is-open::before { transform: rotate(-135deg); }

.copy-code {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px; height: 36px;
    padding: 0;
    color: var(--ink-2);
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-sm);
    cursor: pointer;
    transition: color var(--t) var(--ease), border-color var(--t) var(--ease);
}
.copy-code:hover { color: var(--sky-700); border-color: var(--sky-300); }
.copy-code svg { width: 14px; height: 14px; }

.code-container { position: relative; overflow-x: auto; -webkit-overflow-scrolling: touch; }
.code-block {
    position: relative;
    background: var(--code-bg);
    color: var(--code-text);
    padding: var(--s-5);
    border-radius: var(--r-sm);
    overflow-x: auto;
    max-width: 100%;
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", "Menlo", "Consolas", monospace;
    font-size: var(--fs-sm);
    line-height: 1.65;
    border: 1px solid rgba(115, 185, 230, 0.18);
    font-variant-numeric: tabular-nums;
}
/* Terminal traffic lights */
.code-block::before {
    content: "";
    position: absolute;
    top: var(--s-3);
    left: var(--s-4);
    width: 38px; height: 8px;
    background:
        radial-gradient(circle 3px at 4px 4px, #ED6A5E 60%, transparent 62%) 0 0/14px 8px no-repeat,
        radial-gradient(circle 3px at 4px 4px, #F4BF4F 60%, transparent 62%) 14px 0/14px 8px no-repeat,
        radial-gradient(circle 3px at 4px 4px, #61C554 60%, transparent 62%) 28px 0/14px 8px no-repeat;
    opacity: 0.7;
}
.code-block code { display: block; padding-top: 1.2rem; }
.code-block::-webkit-scrollbar { height: 6px; }
.code-block::-webkit-scrollbar-track { background: rgba(255, 255, 255, 0.04); }
.code-block::-webkit-scrollbar-thumb { background: rgba(115, 185, 230, 0.3); border-radius: var(--r-pill); }

.no-results {
    text-align: center;
    padding: var(--s-12) var(--s-6);
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
}
.no-results h3 {
    color: var(--ink);
    margin-bottom: var(--s-2);
    font-size: var(--fs-lg);
    font-weight: 600;
}
.no-results p { color: var(--ink-2); font-size: var(--fs-sm); }

/* ============================================================
   Skill page — docs-style composition
   ============================================================ */
.skill-hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    padding: 4px 12px;
    font-size: 0.6875rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    color: var(--sky-700);
    background: var(--sky-50);
    border: 1px solid var(--sky-100);
    border-radius: var(--r-pill);
    text-transform: uppercase;
    margin-bottom: var(--s-4);
}
.skill-hero-badge::before {
    content: "";
    width: 6px; height: 6px;
    background: var(--gold);
    border-radius: 50%;
    box-shadow: 0 0 0 4px rgba(242, 181, 60, 0.18);
}

.skill-value-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--s-4);
    text-align: left;
    margin: var(--s-8) 0;
}
.skill-value-card {
    position: relative;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-5) var(--s-5) var(--s-5) var(--s-6);
}
.skill-value-card::before {
    content: "";
    position: absolute;
    left: 0; top: var(--s-5); bottom: var(--s-5);
    width: 2px;
    background: var(--sky);
}
.skill-value-card h3 {
    font-size: var(--fs-md);
    font-weight: 600;
    color: var(--ink);
    margin: 0 0 var(--s-2);
    letter-spacing: -0.005em;
}
.skill-value-card p {
    font-size: var(--fs-sm);
    color: var(--ink-2);
    line-height: 1.65;
    margin: 0;
}

.skill-card {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-6) var(--s-6);
    text-align: left;
    margin-bottom: var(--s-5);
}
.skill-card-title {
    font-size: var(--fs-md);
    font-weight: 600;
    color: var(--ink);
    margin: 0 0 var(--s-4);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--s-3);
    flex-wrap: wrap;
    letter-spacing: -0.005em;
}

.skill-prompt-box {
    position: relative;
    background: var(--code-bg);
    color: var(--code-text);
    border: 1px solid rgba(115, 185, 230, 0.22);
    border-radius: var(--r-sm);
    padding: var(--s-5);
    font-size: var(--fs-sm);
    line-height: 1.7;
}
.skill-prompt-box code,
.skill-prompt-box .api-url-zh,
.skill-prompt-box .api-url-en {
    color: var(--gold-soft);
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
    word-break: break-word;
    overflow-wrap: anywhere;
}
.skill-prompt-box strong { color: #fff; font-weight: 600; }
.skill-prompt-box p { margin: 0 0 var(--s-2); }
.skill-prompt-box p:last-child { margin-bottom: 0; }

.skill-copy-btn {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    padding: var(--s-2) var(--s-3);
    font-size: var(--fs-xs);
    font-weight: 600;
    color: var(--ink-2);
    background: var(--surface);
    border: 1px solid var(--line-2);
    border-radius: var(--r-sm);
    cursor: pointer;
    transition: color var(--t) var(--ease), border-color var(--t) var(--ease);
}
.skill-copy-btn:hover { color: var(--sky-700); border-color: var(--sky-300); }

.skill-github-link {
    display: inline-flex;
    align-items: center;
    gap: var(--s-3);
    padding: var(--s-3) var(--s-5);
    font-size: var(--fs-sm);
    font-weight: 600;
    color: var(--surface);
    background: var(--sky-700);
    border-radius: var(--r-sm);
    text-decoration: none;
    transition: background var(--t) var(--ease);
    word-break: break-all;
}
.skill-github-link:hover { background: var(--sky-900); }
.skill-github-link svg { width: 18px; height: 18px; fill: currentColor; flex: none; }

/* Skill page tables (address + lang) */
.skillapi-table-block { margin-top: var(--s-5); }
.skillapi-table-caption {
    font-size: var(--fs-xs);
    font-weight: 600;
    color: var(--ink-3);
    margin: 0 0 var(--s-2);
    text-transform: uppercase;
    letter-spacing: 0.12em;
}
.skillapi-table-wrap {
    overflow-x: auto;
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-sm);
}
.skillapi-addr-table,
.skillapi-lang-table {
    border-collapse: collapse;
    width: 100%;
    font-size: var(--fs-sm);
    line-height: 1.4;
}
.skillapi-addr-table th, .skillapi-addr-table td,
.skillapi-lang-table th, .skillapi-lang-table td {
    padding: var(--s-3) var(--s-4);
    text-align: left;
    border-bottom: 1px solid var(--line);
    color: var(--ink-2);
    vertical-align: middle;
}
.skillapi-addr-table tbody tr:last-child td,
.skillapi-lang-table tbody tr:last-child td { border-bottom: none; }
.skillapi-addr-table thead th,
.skillapi-lang-table thead th {
    background: var(--sky-50);
    color: var(--ink);
    font-size: var(--fs-xs);
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    border-bottom: 1px solid var(--line-2);
}
.skillapi-addr-table code,
.skillapi-lang-table code {
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
    color: var(--sky-700);
    font-size: var(--fs-sm);
}

/* ============================================================
   Articles (notes)
   ============================================================ */
.article {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: clamp(32px, 5vw, 56px) clamp(24px, 4vw, 48px);
    margin-top: var(--s-8);
    max-width: 760px;
    margin-left: auto;
    margin-right: auto;
}
.article h1 {
    font-size: var(--fs-3xl);
    font-weight: 700;
    letter-spacing: -0.03em;
    color: var(--ink);
    margin-bottom: var(--s-3);
    line-height: 1.15;
}
.article .meta {
    color: var(--ink-3);
    font-size: var(--fs-xs);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--s-6);
    padding-bottom: var(--s-5);
    border-bottom: 1px solid var(--line);
    font-variant-numeric: tabular-nums;
}
.article h2 {
    font-size: var(--fs-xl);
    font-weight: 600;
    letter-spacing: -0.015em;
    color: var(--ink);
    margin: var(--s-10) 0 var(--s-3);
    padding-top: var(--s-5);
    border-top: 1px solid var(--line);
}
.article h3 {
    font-size: var(--fs-md);
    font-weight: 600;
    color: var(--ink);
    margin: var(--s-6) 0 var(--s-2);
}
.article p {
    color: var(--ink-2);
    font-size: var(--fs-base);
    line-height: 1.75;
    margin: var(--s-3) 0;
    max-width: 65ch;
}
.article code, .article pre {
    font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
}
.article code {
    padding: 1px 6px;
    font-size: 0.9em;
    color: var(--sky-700);
    background: var(--sky-50);
    border: 1px solid var(--sky-100);
    border-radius: var(--r-xs);
}
.article pre {
    background: var(--code-bg);
    color: var(--code-text);
    padding: var(--s-5);
    border-radius: var(--r-sm);
    overflow-x: auto;
    margin: var(--s-5) 0;
    font-size: var(--fs-sm);
    line-height: 1.65;
    border: 1px solid rgba(115, 185, 230, 0.18);
}
.article pre code {
    padding: 0;
    background: transparent;
    border: none;
    color: inherit;
    font-size: inherit;
}
.article ul, .article ol {
    margin: var(--s-3) 0 var(--s-3) var(--s-6);
    color: var(--ink-2);
    line-height: 1.75;
}
.article li { margin-bottom: var(--s-1); }
.article a { color: var(--sky-700); text-underline-offset: 2px; }
.article a:hover { color: var(--sky-900); }
.article strong { color: var(--ink); font-weight: 600; }

.highlight-box {
    background: var(--sky-50);
    border-left: 2px solid var(--sky-500);
    border-radius: 0 var(--r-sm) var(--r-sm) 0;
    padding: var(--s-4) var(--s-5);
    margin: var(--s-5) 0;
}
.highlight-box strong { color: var(--ink); }

.back-link {
    display: inline-flex;
    align-items: center;
    gap: var(--s-2);
    font-size: var(--fs-sm);
    color: var(--ink-2);
    text-decoration: none;
    margin-top: var(--s-6);
}
.back-link:hover { color: var(--sky-700); }

/* ============================================================
   404 page — editorial error
   ============================================================ */
.error-section { padding: var(--s-8) 0; }
.error-card {
    background: var(--surface);
    border: 1px solid var(--line);
    border-radius: var(--r-md);
    padding: var(--s-12) var(--s-6);
    text-align: center;
    max-width: 560px;
    margin: 0 auto;
}
.error-icon { margin-bottom: var(--s-6); }
.error-title {
    font-size: var(--fs-3xl);
    font-weight: 700;
    letter-spacing: -0.025em;
    color: var(--ink);
    margin-bottom: var(--s-3);
}
.error-message {
    color: var(--ink-2);
    font-size: var(--fs-base);
    line-height: 1.65;
    margin-bottom: var(--s-8);
}
.error-actions {
    display: flex;
    gap: var(--s-3);
    justify-content: center;
    margin-bottom: var(--s-8);
    flex-wrap: wrap;
}
.btn-primary,
.btn-secondary {
    display: inline-flex;
    align-items: center;
    padding: var(--s-3) var(--s-5);
    font-size: var(--fs-sm);
    font-weight: 500;
    border-radius: var(--r-sm);
    text-decoration: none;
    transition: background var(--t) var(--ease),
                color var(--t) var(--ease),
                border-color var(--t) var(--ease);
}
.btn-primary {
    color: var(--surface);
    background: var(--sky-700);
    border: 1px solid var(--sky-700);
}
.btn-primary:hover { background: var(--sky-900); border-color: var(--sky-900); }
.btn-secondary {
    color: var(--ink);
    background: transparent;
    border: 1px solid var(--line-2);
}
.btn-secondary:hover { color: var(--sky-700); border-color: var(--sky-300); }

.error-suggestions {
    text-align: left;
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: var(--r-sm);
    padding: var(--s-5) var(--s-6);
}
.error-suggestions h3 {
    font-size: var(--fs-xs);
    font-weight: 600;
    color: var(--ink-3);
    text-transform: uppercase;
    letter-spacing: 0.12em;
    margin-bottom: var(--s-3);
}
.error-suggestions ul { list-style: none; padding: 0; }
.error-suggestions li {
    color: var(--ink-2);
    font-size: var(--fs-sm);
    padding: var(--s-2) 0;
    border-top: 1px solid var(--line);
    line-height: 1.6;
}
.error-suggestions li:first-child { border-top: none; }
.error-suggestions li::before {
    content: "→";
    color: var(--sky-500);
    margin-right: var(--s-3);
    font-family: ui-monospace, monospace;
}
.error-suggestions a { color: var(--sky-700); text-decoration: none; }
.error-suggestions a:hover { color: var(--sky-900); text-decoration: underline; }

/* ============================================================
   Footer
   ============================================================ */
footer {
    background: var(--surface);
    border-top: 1px solid var(--line);
    color: var(--ink-2);
    text-align: center;
    padding: var(--s-8) 0;
    margin-top: var(--s-20);
}
footer p { font-size: var(--fs-sm); }
.footer-publisher { margin-top: var(--s-2); font-size: var(--fs-xs); }
.footer-publisher a { color: var(--ink-3); text-decoration: none; }
.footer-publisher a:hover { color: var(--sky-900); text-decoration: underline; }
.friend-links {
    margin-top: var(--s-3);
    font-size: var(--fs-xs);
    color: var(--ink-3);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}
.friend-links span { margin-right: var(--s-2); }
.friend-links a {
    color: var(--ink-3);
    text-decoration: none;
    margin: 0 var(--s-2);
    transition: color var(--t) var(--ease);
}
.friend-links a:hover { color: var(--sky-700); }

/* ============================================================
   Reveal animations
   ============================================================ */
@keyframes reveal-up {
    from { opacity: 0; transform: translateY(16px); }
    to   { opacity: 1; transform: translateY(0); }
}
.reveal { opacity: 0; animation: reveal-up var(--t-slow) var(--ease-out) forwards; }
.reveal-1 { animation-delay: 0.05s; }
.reveal-2 { animation-delay: 0.13s; }
.reveal-3 { animation-delay: 0.21s; }
.reveal-4 { animation-delay: 0.29s; }
.reveal-5 { animation-delay: 0.37s; }
.function-card:nth-child(2) { animation-delay: 0.06s; }
.function-card:nth-child(3) { animation-delay: 0.12s; }
.function-card:nth-child(4) { animation-delay: 0.18s; }
.function-card:nth-child(n+5) { animation-delay: 0.24s; }

/* ============================================================
   Internationalisation
   ============================================================ */
.name-en, .desc-en { display: none; }
[data-lang="en"] .name-zh, [data-lang="en"] .desc-zh { display: none; }
[data-lang="en"] .name-en, [data-lang="en"] .desc-en { display: block; }

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 960px) {
    .features-grid {
        grid-template-columns: 1fr;
    }
    .feature-card,
    .feature-card:nth-child(n) { grid-column: 1 / -1; }

    .latest-list { grid-template-columns: 1fr; }
    .post-item,
    .post-item:nth-child(n) { grid-column: 1 / -1; }

    .info-grid { grid-template-columns: 1fr; }
    .info-card,
    .info-card:nth-child(n) { grid-column: 1 / -1; }
}

@media (max-width: 768px) {
    header { padding: var(--s-3) 0; }
    header .container { flex-direction: column; gap: var(--s-3); text-align: center; }
    .logo h1 { font-size: var(--fs-lg); }
    .logo p { font-size: var(--fs-sm); }

    .search-section { padding: var(--s-10) var(--s-5); }
    .search-form.compact {
        grid-template-columns: 1fr;
    }
    .search-form.compact .search-input-wrapper,
    .language-filter.inline select,
    .search-form.compact .search-btn {
        height: 48px;
        font-size: var(--fs-base);
    }

    .function-header { flex-direction: column; align-items: flex-start; }
    .function-name { flex-direction: column; align-items: flex-start; gap: var(--s-2); }
    .function-details { grid-template-columns: 1fr; gap: var(--s-3); }
    .scores { gap: var(--s-6); flex-wrap: wrap; }
    .skill-value-grid { grid-template-columns: 1fr; }
    .skill-card { padding: var(--s-5); }
}

@media (max-width: 480px) {
    .container { padding: 0 var(--s-4); }
    .search-section { padding: var(--s-8) var(--s-4); }
    .search-section h2 { font-size: var(--fs-3xl); }
    .function-card { padding: var(--s-5) var(--s-4); }
    .name-wrapper h3 { font-size: var(--fs-lg); }
    .code-block { font-size: 0.8rem; padding: var(--s-4); }
    .code-block code { padding-top: 1rem; }
    .language-switcher a, .language-switcher button { padding: var(--s-2) var(--s-3); font-size: var(--fs-xs); }
    .article { padding: var(--s-6) var(--s-4); }
}

/* ============================================================
   Reduced motion
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
    }
    .reveal, .function-card { opacity: 1 !important; transform: none !important; }
}