/* ──────────────────────────────────────────────────────────────────────────
   markast — documentation site
   Design tokens, layout, components.
   ────────────────────────────────────────────────────────────────────────── */

/* === Reset / base ====================================================== */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body, h1, h2, h3, h4, p, ul, ol, figure, blockquote { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; cursor: pointer; }
a { color: inherit; text-decoration: none; }

/* === Tokens (light) ==================================================== */
:root {
    --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: "JetBrains Mono", "SFMono-Regular", Menlo, Consolas, monospace;

    /* Surface palette */
    --bg:           #fafaf9;
    --bg-elev:      #ffffff;
    --bg-code:      #f4f4f3;
    --bg-soft:      rgba(120, 100, 200, 0.04);
    --border:       rgba(0, 0, 0, 0.08);
    --border-strong:rgba(0, 0, 0, 0.14);

    /* Text */
    --text:         #18181b;
    --text-muted:   #6b7280;
    --text-subtle:  #9ca3af;

    /* Accent */
    --accent:       #6d52ff;
    --accent-hover: #5a3fee;
    --accent-soft:  rgba(109, 82, 255, 0.10);
    --accent-ring:  rgba(109, 82, 255, 0.32);

    /* Semantic */
    --success:      #16a34a;
    --warning:      #d97706;
    --danger:       #dc2626;
    --info:         #0284c7;

    /* Layout */
    --nav-h:        56px;
    --sidebar-w:    260px;
    --toc-w:        220px;
    --content-max:  760px;
    --radius:       10px;
    --radius-sm:    6px;

    /* Effects */
    --shadow-sm:    0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md:    0 6px 24px rgba(15, 15, 30, 0.06);
    --shadow-lg:    0 16px 48px rgba(15, 15, 30, 0.08);

    color-scheme: light;
}

/* === Tokens (dark) ===================================================== */
[data-theme="dark"] {
    --bg:           #0c0c0f;
    --bg-elev:      #131318;
    --bg-code:      #16161b;
    --bg-soft:      rgba(150, 130, 240, 0.06);
    --border:       rgba(255, 255, 255, 0.08);
    --border-strong:rgba(255, 255, 255, 0.16);

    --text:         #ededed;
    --text-muted:   #9ca3af;
    --text-subtle:  #6b7280;

    --accent:       #8b73ff;
    --accent-hover: #a08eff;
    --accent-soft:  rgba(139, 115, 255, 0.14);
    --accent-ring:  rgba(139, 115, 255, 0.42);

    --shadow-sm:    0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md:    0 6px 24px rgba(0, 0, 0, 0.4);
    --shadow-lg:    0 16px 48px rgba(0, 0, 0, 0.5);

    color-scheme: dark;
}

/* === Body ============================================================== */
body {
    font-family: var(--font-sans);
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    font-size: 15.5px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    font-feature-settings: "cv11", "ss01";
    transition: background 200ms ease, color 200ms ease;
}

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

/* === Top navigation ==================================================== */
.nav {
    position: sticky;
    top: 0;
    z-index: 50;
    height: var(--nav-h);
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 0 24px;
    background: color-mix(in srgb, var(--bg) 78%, transparent);
    backdrop-filter: saturate(160%) blur(18px);
    -webkit-backdrop-filter: saturate(160%) blur(18px);
    border-bottom: 1px solid var(--border);
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 700;
    letter-spacing: -0.01em;
    font-size: 16px;
}

.nav-brand-mark {
    width: 22px; height: 22px;
    display: block;
}

.nav-brand small {
    font-weight: 500;
    color: var(--text-muted);
    font-size: 12px;
    border: 1px solid var(--border);
    padding: 1px 6px;
    border-radius: 999px;
    margin-left: 4px;
}

.nav-spacer { flex: 1; }

.nav-actions { display: flex; align-items: center; gap: 4px; }

.nav-btn {
    display: inline-flex; align-items: center; justify-content: center;
    height: 36px; min-width: 36px; padding: 0 10px;
    border-radius: 8px;
    color: var(--text-muted);
    font-size: 13px; font-weight: 500;
    transition: background 120ms ease, color 120ms ease;
}
.nav-btn:hover { background: var(--bg-soft); color: var(--text); }
.nav-btn svg { width: 16px; height: 16px; }
.nav-btn[aria-pressed="true"] { color: var(--text); background: var(--bg-soft); }

.nav-toggle {
    display: none;
    height: 36px; width: 36px;
    border-radius: 8px;
    color: var(--text-muted);
    align-items: center; justify-content: center;
}
.nav-toggle svg { width: 18px; height: 18px; }

/* === Layout shell ====================================================== */
.shell {
    display: grid;
    grid-template-columns: var(--sidebar-w) minmax(0, 1fr) var(--toc-w);
    gap: 36px;
    max-width: 1320px;
    margin: 0 auto;
    padding: 0 24px;
}

@media (max-width: 1280px) {
    .shell { gap: 28px; }
}
@media (max-width: 1100px) {
    .shell { grid-template-columns: var(--sidebar-w) minmax(0, 1fr); gap: 28px; }
    .toc { display: none; }
}
@media (max-width: 820px) {
    .shell {
        grid-template-columns: 1fr;
        gap: 0;
        padding: 0 18px;
    }
    .nav-toggle { display: inline-flex; }
    .nav { padding: 0 14px; gap: 6px; }
    .nav-brand small { display: none; }
    .nav-btn { padding: 0 8px; min-width: 34px; height: 34px; font-size: 12.5px; }
    .main { padding: 32px 0 64px; }
    .content h1 { font-size: 30px; }
    .content h2 { font-size: 20px; margin-top: 44px; }
    .content h3 { font-size: 16px; margin-top: 26px; }
    .content h1 + .lede { font-size: 16px; }
    .content pre { font-size: 12.8px; padding: 14px; border-radius: 8px; }
    .feature-grid { grid-template-columns: 1fr; }
}
@media (max-width: 480px) {
    .shell { padding: 0 14px; }
    .nav-actions .lang-only-desktop { display: none; }
    .nav-btn[aria-label] span:not(.icon-sun):not(.icon-moon) { display: none; }
    .content h1 { font-size: 26px; }
    .hero { padding: 48px 0 36px; }
}

/* Tables wrap horizontally on small screens */
@media (max-width: 640px) {
    .content { overflow-x: hidden; }
    .content table { display: block; overflow-x: auto; white-space: nowrap; }
    .content table th, .content table td { white-space: normal; }
    .page-footer { flex-direction: column; align-items: stretch; }
    .page-footer a { justify-content: center; }
}

/* === Sidebar =========================================================== */
.sidebar {
    position: sticky;
    top: var(--nav-h);
    align-self: start;
    height: calc(100vh - var(--nav-h));
    overflow-y: auto;
    padding: 28px 8px 48px 0;
    border-right: 1px solid var(--border);
    margin-right: -16px;
    padding-right: 16px;
    scrollbar-width: thin;
}
.sidebar::-webkit-scrollbar { width: 8px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--border); border-radius: 999px; }

.sidebar h4 {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-subtle);
    margin: 24px 14px 8px;
}
.sidebar h4:first-child { margin-top: 0; }

.sidebar a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 7px 14px;
    margin: 1px 0;
    border-radius: 6px;
    color: var(--text-muted);
    font-size: 14px;
    transition: color 100ms ease, background 100ms ease;
}
.sidebar a:hover { color: var(--text); background: var(--bg-soft); }
.sidebar a.active {
    color: var(--accent);
    background: var(--accent-soft);
    font-weight: 500;
}

@media (max-width: 820px) {
    .sidebar {
        position: fixed;
        top: var(--nav-h);
        left: 0;
        width: 280px;
        height: calc(100vh - var(--nav-h));
        background: var(--bg);
        border-right: 1px solid var(--border);
        padding: 28px 16px 48px;
        margin-right: 0;
        transform: translateX(-100%);
        transition: transform 220ms cubic-bezier(0.2, 0.8, 0.2, 1);
        z-index: 40;
    }
    .sidebar.open { transform: translateX(0); box-shadow: var(--shadow-lg); }
}

.sidebar-backdrop {
    display: none;
    position: fixed;
    inset: var(--nav-h) 0 0 0;
    background: rgba(0,0,0,0.4);
    z-index: 35;
    opacity: 0; pointer-events: none;
    transition: opacity 200ms ease;
}
.sidebar-backdrop.show { display: block; opacity: 1; pointer-events: auto; }

/* === Main content ====================================================== */
.main { padding: 56px 0 96px; min-width: 0; }
.content { max-width: var(--content-max); }

.content h1 {
    font-size: 36px;
    line-height: 1.15;
    font-weight: 700;
    letter-spacing: -0.025em;
    margin-bottom: 14px;
}
.content h1 + .lede {
    color: var(--text-muted);
    font-size: 17px;
    line-height: 1.55;
    margin-bottom: 32px;
}

.content h2 {
    font-size: 22px;
    line-height: 1.3;
    font-weight: 650;
    letter-spacing: -0.015em;
    margin-top: 56px;
    margin-bottom: 14px;
    padding-top: 14px;
    border-top: 1px solid var(--border);
    scroll-margin-top: calc(var(--nav-h) + 16px);
}
.content h2:first-child { border-top: 0; padding-top: 0; margin-top: 0; }

.content h3 {
    font-size: 17px;
    font-weight: 600;
    letter-spacing: -0.01em;
    margin-top: 32px;
    margin-bottom: 10px;
    scroll-margin-top: calc(var(--nav-h) + 16px);
}

.content h4 {
    font-size: 15px;
    font-weight: 600;
    margin-top: 24px;
    margin-bottom: 8px;
    color: var(--text-muted);
}

.content p { margin: 14px 0; }
.content p + p { margin-top: 14px; }

.content a {
    color: var(--accent);
    border-bottom: 1px solid color-mix(in srgb, var(--accent) 30%, transparent);
    transition: border-color 100ms ease;
}
.content a:hover { border-bottom-color: var(--accent); }

.content ul, .content ol { margin: 14px 0; padding-left: 22px; }
.content ul li { list-style: disc; margin: 6px 0; }
.content ol li { list-style: decimal; margin: 6px 0; }
.content li::marker { color: var(--text-subtle); }

.content strong { font-weight: 650; color: var(--text); }
.content em { font-style: italic; }

/* Inline code */
.content code:not(pre code) {
    font-family: var(--font-mono);
    font-size: 0.88em;
    padding: 2px 6px;
    border-radius: 4px;
    background: var(--bg-code);
    border: 1px solid var(--border);
    color: color-mix(in srgb, var(--accent) 80%, var(--text));
}

/* Code blocks */
.content pre {
    font-family: var(--font-mono);
    font-size: 13.5px;
    line-height: 1.55;
    background: var(--bg-code);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px 18px;
    margin: 18px 0;
    overflow-x: auto;
    box-shadow: var(--shadow-sm);
}
.content pre code { font-family: inherit; font-size: inherit; padding: 0; background: transparent; border: 0; color: var(--text); }

/* Tables */
.content table {
    width: 100%;
    border-collapse: collapse;
    margin: 18px 0;
    font-size: 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}
.content thead { background: var(--bg-soft); }
.content th, .content td {
    text-align: left;
    padding: 10px 14px;
    border-bottom: 1px solid var(--border);
}
.content th { font-weight: 600; color: var(--text); }
.content tr:last-child td { border-bottom: 0; }

/* Blockquotes */
.content blockquote {
    margin: 18px 0;
    padding: 12px 18px;
    border-left: 3px solid var(--accent);
    background: var(--accent-soft);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    color: var(--text);
}
.content blockquote p { margin: 6px 0; }

/* Horizontal rule */
.content hr { border: 0; border-top: 1px solid var(--border); margin: 32px 0; }

/* Callouts */
.callout {
    margin: 22px 0;
    padding: 14px 18px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    background: var(--bg-elev);
    display: flex;
    gap: 14px;
}
.callout-icon {
    width: 22px; height: 22px;
    flex: none;
    border-radius: 6px;
    display: grid; place-items: center;
    color: white;
    font-size: 12px;
    font-weight: 700;
}
.callout-tip   { border-color: color-mix(in srgb, var(--accent) 35%, var(--border)); }
.callout-tip   .callout-icon { background: var(--accent); }
.callout-info  { border-color: color-mix(in srgb, var(--info) 35%, var(--border)); }
.callout-info  .callout-icon { background: var(--info); }
.callout-warn  { border-color: color-mix(in srgb, var(--warning) 35%, var(--border)); }
.callout-warn  .callout-icon { background: var(--warning); }
.callout-body p:first-child { margin-top: 0; }
.callout-body p:last-child  { margin-bottom: 0; }
.callout-body strong { color: var(--text); }

/* === Right TOC ========================================================= */
.toc {
    position: sticky;
    top: var(--nav-h);
    align-self: start;
    height: calc(100vh - var(--nav-h));
    padding: 56px 0 48px 12px;
    border-left: 1px solid var(--border);
    margin-left: -12px;
    overflow-y: auto;
}
.toc h5 {
    font-size: 11px;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-subtle);
    margin: 0 0 12px;
}
.toc a {
    display: block;
    padding: 4px 0;
    font-size: 13px;
    color: var(--text-muted);
    border-bottom: 0;
    transition: color 100ms ease;
}
.toc a:hover, .toc a.active { color: var(--accent); }
.toc .toc-h3 { padding-left: 12px; font-size: 12.5px; }

/* === Page footer ======================================================= */
.page-footer {
    margin-top: 80px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    font-size: 14px;
    color: var(--text-muted);
}
.page-footer a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    border-radius: 8px;
    border: 1px solid var(--border);
    transition: background 100ms ease, border-color 100ms ease;
    color: var(--text);
}
.page-footer a:hover { background: var(--bg-soft); border-color: var(--border-strong); }
.page-footer .footer-prev::before { content: "←"; margin-right: 6px; }
.page-footer .footer-next::after  { content: "→"; margin-left: 6px; }

/* === Hero (landing) ==================================================== */
.hero {
    padding: 80px 0 60px;
    text-align: left;
    border-bottom: 1px solid var(--border);
    margin-bottom: 48px;
    position: relative;
}
.hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(60% 60% at 30% 20%, color-mix(in srgb, var(--accent) 12%, transparent), transparent 70%),
        radial-gradient(40% 40% at 80% 30%, color-mix(in srgb, #14b8a6 10%, transparent), transparent 70%);
    pointer-events: none;
    z-index: -1;
}
.hero-title {
    font-size: 56px;
    font-weight: 700;
    letter-spacing: -0.04em;
    line-height: 1.05;
    margin-bottom: 18px;
}
.hero-title .grad {
    background: linear-gradient(110deg, var(--accent), color-mix(in srgb, var(--accent) 40%, #14b8a6));
    -webkit-background-clip: text; background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero-sub {
    font-size: 19px;
    color: var(--text-muted);
    max-width: 640px;
    line-height: 1.5;
}
.hero-cta { display: flex; gap: 10px; margin-top: 30px; flex-wrap: wrap; }

@media (max-width: 640px) { .hero-title { font-size: 40px; } .hero-sub { font-size: 16px; } }

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    height: 42px;
    padding: 0 20px;
    border-radius: 10px;
    font-weight: 500;
    font-size: 14.5px;
    transition: background 120ms ease, transform 120ms ease, box-shadow 120ms ease;
    border-bottom: 0 !important;
}
.btn-primary {
    background: var(--accent);
    color: white !important;
    box-shadow: 0 6px 20px var(--accent-ring);
}
.btn-primary:hover { background: var(--accent-hover); transform: translateY(-1px); }
.btn-ghost {
    border: 1px solid var(--border-strong);
    color: var(--text) !important;
}
.btn-ghost:hover { background: var(--bg-soft); }

/* === Feature grid ====================================================== */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
    margin: 32px 0;
}
.feature-card {
    padding: 22px;
    border-radius: var(--radius);
    background: var(--bg-elev);
    border: 1px solid var(--border);
    transition: border-color 120ms ease, transform 120ms ease;
}
.feature-card:hover { border-color: var(--border-strong); transform: translateY(-2px); }
.feature-card-icon {
    width: 36px; height: 36px;
    border-radius: 8px;
    background: var(--accent-soft);
    color: var(--accent);
    display: grid; place-items: center;
    font-size: 18px;
    margin-bottom: 14px;
}
.feature-card h3 { margin: 0 0 6px; font-size: 16px; font-weight: 600; }
.feature-card p { margin: 0; color: var(--text-muted); font-size: 14px; line-height: 1.55; }

/* === Helpers =========================================================== */
.muted { color: var(--text-muted); }
.center { text-align: center; }
.kbd {
    display: inline-block;
    padding: 1px 6px;
    border-radius: 4px;
    border: 1px solid var(--border-strong);
    background: var(--bg-elev);
    font-family: var(--font-mono);
    font-size: 12px;
}

/* === Prism overrides =================================================== */
:root {
    --code-base:        #1f2328;
    --code-comment:     #6b7280;
    --code-string:      #16a34a;
    --code-keyword:     #6d52ff;
    --code-fn:          #2563eb;
    --code-classname:   #b45309;
    --code-tag:         #b91c1c;
    --code-attr:        #9333ea;
    --code-number:      #c2410c;
    --code-punct:       #6b7280;
}
[data-theme="dark"] {
    --code-base:        #e7e9ee;
    --code-comment:     #7d8290;
    --code-string:      #7ee787;
    --code-keyword:     #ff7b72;
    --code-fn:          #d2a8ff;
    --code-classname:   #ffa657;
    --code-tag:         #79c0ff;
    --code-attr:        #f0a868;
    --code-number:      #79c0ff;
    --code-punct:       #c9d1d9;
}
pre[class*="language-"],
code[class*="language-"] {
    background: transparent !important;
    color: var(--code-base) !important;
    text-shadow: none !important;
    font-family: var(--font-mono) !important;
}
.content pre { background: var(--bg-code); }
.token { background: transparent !important; }
.token.comment, .token.prolog, .token.doctype, .token.cdata { color: var(--code-comment); font-style: italic; }
.token.string, .token.char, .token.attr-value, .token.regex { color: var(--code-string); }
.token.keyword, .token.boolean, .token.constant, .token.builtin, .token.important, .token.atrule { color: var(--code-keyword); }
.token.function { color: var(--code-fn); }
.token.class-name, .token.namespace { color: var(--code-classname); }
.token.tag, .token.selector, .token.symbol { color: var(--code-tag); }
.token.attr-name, .token.property, .token.variable { color: var(--code-attr); }
.token.number { color: var(--code-number); }
.token.operator, .token.punctuation, .token.entity { color: var(--code-punct); }
.token.deleted { color: #f87171; }
.token.inserted { color: #4ade80; }

/* === Animations ======================================================== */
@media (prefers-reduced-motion: no-preference) {
    .content > * { animation: fadeUp 320ms cubic-bezier(0.2, 0.8, 0.2, 1) backwards; }
    .content > *:nth-child(1) { animation-delay: 0ms; }
    .content > *:nth-child(2) { animation-delay: 30ms; }
    .content > *:nth-child(3) { animation-delay: 60ms; }
    .content > *:nth-child(4) { animation-delay: 90ms; }
}
@keyframes fadeUp {
    from { opacity: 0; transform: translateY(6px); }
    to   { opacity: 1; transform: translateY(0); }
}