/* ============================================================
   vLLM 学习手册 — editorial book style
   Inspired by NousResearch/hermes tutorial palette.
   ============================================================ */

:root {
    /* 纸质米白背景 */
    --bg:           #fbfaf6;
    --bg-elev:      #f3f1e8;
    --bg-elev-2:    #e9e6d9;
    --bg-code:      #f6f4eb;
    --bg-hover:     #efece1;

    /* 暖深棕黑前景 */
    --fg:           #2a2723;
    --fg-soft:      #4d4a44;
    --fg-dim:       #807c75;
    --fg-bright:    #1a1814;

    /* 主强调：深酒红 */
    --accent:       #8b1538;
    --accent-dim:   #6b1028;
    --accent-soft:  #b04658;

    /* 链接：深靛蓝 */
    --link:         #1a4d80;
    --link-hover:   #0d3a66;

    /* 边框 */
    --border:        #d6d3c4;
    --border-soft:   #e6e3d4;
    --border-strong: #c2bea9;

    /* 语义色（callout） */
    --warn:      #b85c00;
    --warn-bg:   #faf0e3;
    --info:      #2c5282;
    --info-bg:   #e8eff5;
    --good:      #2f5d3a;
    --good-bg:   #ecf3eb;
    --research:  #6b4488;
    --research-bg:#f0eaf1;
    --tip-bg:    #f5ede0;

    /* 代码语法高亮 */
    --code-keyword: #8b1538;
    --code-string:  #2e6a3e;
    --code-comment: #807c70;
    --code-fn:      #1e5a99;
    --code-name:    #a82c30;
    --code-num:     #a86420;
    --code-default: #2a2723;

    /* layout */
    --sidebar-w:  292px;
    --toc-w:      220px;
    --content-w:  760px;
    --radius:     6px;
    --radius-sm:  4px;

    --font-sans: -apple-system, BlinkMacSystemFont, "Helvetica Neue",
                 "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei",
                 "Source Sans 3", Helvetica, Arial, sans-serif;
    --font-mono: ui-monospace, "SF Mono", "Cascadia Code",
                 "JetBrains Mono", Menlo, Consolas, monospace;
    --font-serif: Georgia, "Iowan Old Style", "Source Serif Pro", serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 1.5rem; }

html, body {
    margin: 0; padding: 0;
    background: var(--bg);
    color: var(--fg);
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

a {
    color: var(--link);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: border-color 0.12s, color 0.12s;
}
a:hover {
    color: var(--link-hover);
    border-bottom-color: var(--link-hover);
}

/* ============================================================
   LAYOUT
   ============================================================ */

.app-layout {
    display: grid;
    grid-template-columns: var(--sidebar-w) minmax(0, 1fr) var(--toc-w);
    min-height: 100vh;
}

nav.sidebar {
    background: var(--bg-elev);
    border-right: 1px solid var(--border);
    padding: 26px 22px;
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
    font-size: 13.5px;
}
nav.sidebar::-webkit-scrollbar { width: 8px; }
nav.sidebar::-webkit-scrollbar-track { background: transparent; }
nav.sidebar::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 4px; }

.book-title {
    font-size: 17px;
    font-weight: 700;
    color: var(--accent);
    margin: 0 0 4px 0;
    letter-spacing: 0.2px;
}
.book-title a { color: var(--accent); border: none; }
.book-title a:hover { color: var(--accent-dim); border: none; }

.book-sub {
    color: var(--fg-dim);
    font-size: 11px;
    margin-bottom: 22px;
    letter-spacing: 1.2px;
    text-transform: uppercase;
}

.home-link {
    display: inline-block;
    color: var(--fg-soft);
    font-size: 12.5px;
    margin-bottom: 14px;
    border: none;
}
.home-link:hover { color: var(--accent); border: none; }

/* Search input in sidebar */
.search-wrap { position: relative; margin: 10px 0 8px 0; }
#search-input {
    width: 100%;
    background: var(--bg);
    color: var(--fg);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 6px 10px 6px 28px;
    font-size: 12.5px;
    outline: none;
    font-family: var(--font-sans);
    transition: border-color 0.15s;
}
#search-input:focus { border-color: var(--accent); }
.search-wrap::before {
    content: "⌕";
    position: absolute;
    top: 50%;
    left: 9px;
    transform: translateY(-50%);
    font-size: 14px;
    color: var(--fg-dim);
}
#search-results {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    margin-top: 8px;
    max-height: 340px;
    overflow-y: auto;
    display: none;
    font-size: 12.5px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}
#search-results.active { display: block; }
.result {
    padding: 8px 10px;
    border-bottom: 1px solid var(--border-soft);
    cursor: pointer;
    line-height: 1.5;
}
.result:last-child { border-bottom: none; }
.result:hover { background: var(--bg-hover); }
.result-title { font-weight: 600; color: var(--fg-bright); }
.result-section { font-size: 10.5px; color: var(--fg-dim); margin-bottom: 2px; }
.result-snippet { color: var(--fg-soft); margin-top: 4px; }
.result-snippet mark { background: var(--tip-bg); padding: 0 2px; border-radius: 2px; color: var(--fg); }
.empty { padding: 14px; color: var(--fg-dim); text-align: center; }

/* Sidebar Part groups */
.sidebar .part {
    margin-top: 18px;
    padding-top: 12px;
    border-top: 1px solid var(--border-soft);
}
.sidebar .part:first-of-type {
    margin-top: 12px;
    padding-top: 12px;
}
.sidebar .part-label {
    text-transform: uppercase;
    font-size: 10.5px;
    letter-spacing: 1.4px;
    color: var(--accent);
    font-weight: 700;
    margin-bottom: 8px;
}
.sidebar .part-name {
    font-size: 13.5px;
    color: var(--fg);
    font-weight: 600;
    margin-bottom: 8px;
}

.sidebar ol.chapters {
    list-style: none;
    margin: 0;
    padding: 0;
    counter-reset: ch;
}
.sidebar ol.chapters li {
    counter-increment: ch;
    margin: 2px 0;
    position: relative;
}
.sidebar ol.chapters a {
    display: block;
    padding: 4px 8px 4px 36px;
    color: var(--fg-soft);
    border-radius: var(--radius-sm);
    border: none;
    line-height: 1.45;
    position: relative;
}
.sidebar ol.chapters a::before {
    content: attr(data-num);
    position: absolute;
    left: 8px;
    top: 4px;
    color: var(--fg-dim);
    font-size: 11px;
    font-family: var(--font-mono);
    width: 24px;
}
.sidebar ol.chapters a:hover {
    background: var(--bg-hover);
    color: var(--accent);
    border: none;
}
.sidebar ol.chapters li.current > a {
    background: var(--tip-bg);
    color: var(--accent);
    font-weight: 600;
}
.sidebar ol.chapters li.current > a::before {
    color: var(--accent);
}

/* ============================================================
   MAIN CONTENT
   ============================================================ */

main.content {
    padding: 56px 64px 96px 64px;
    max-width: var(--content-w);
    margin: 0 auto;
}

.breadcrumb {
    font-size: 12px;
    color: var(--fg-dim);
    margin-bottom: 12px;
    letter-spacing: 0.02em;
    text-transform: uppercase;
}
.breadcrumb .part-tag {
    color: var(--accent);
    font-weight: 700;
}
.breadcrumb a { color: var(--fg-dim); border: none; }
.breadcrumb a:hover { color: var(--accent); border: none; }

.reading-time {
    display: inline-flex; align-items: center; gap: 6px;
    font-size: 12px;
    color: var(--fg-dim);
    background: var(--bg-elev);
    border: 1px solid var(--border-soft);
    border-radius: 999px;
    padding: 3px 12px;
    margin: 0 0 24px 0;
}
.reading-time::before { content: "⏱"; font-size: 13px; }

/* TOC rail (right) */
aside.toc-rail {
    position: sticky;
    top: 0;
    height: 100vh;
    padding: 56px 24px 32px 0;
    overflow-y: auto;
    font-size: 13px;
}
.toc-rail h4 {
    margin: 0 0 10px 0;
    font-size: 10.5px;
    font-weight: 700;
    color: var(--fg-dim);
    text-transform: uppercase;
    letter-spacing: 1.4px;
}
.toc-rail ul { list-style: none; padding: 0; margin: 0; }
.toc-rail li { margin: 2px 0; }
.toc-rail a {
    color: var(--fg-soft);
    display: block;
    padding: 3px 8px;
    border-left: 2px solid transparent;
    line-height: 1.45;
    border-bottom: none;
}
.toc-rail a:hover {
    color: var(--accent);
    border-left-color: var(--accent);
    border-bottom: none;
}
.toc-rail li.toc-h3 a { padding-left: 20px; font-size: 12px; }

@media (max-width: 1180px) {
    .app-layout { grid-template-columns: var(--sidebar-w) minmax(0, 1fr); }
    aside.toc-rail { display: none; }
}
@media (max-width: 900px) {
    .app-layout { grid-template-columns: 1fr; }
    nav.sidebar {
        position: static;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--border);
    }
    main.content { padding: 30px 22px 64px 22px; }
}

/* ============================================================
   PROSE
   ============================================================ */

.markdown-body { max-width: 100%; }

.markdown-body h1, .markdown-body h2,
.markdown-body h3, .markdown-body h4 {
    color: var(--fg-bright);
    font-weight: 700;
    line-height: 1.3;
}
.markdown-body h1 {
    font-size: 32px;
    margin: 0 0 24px 0;
    padding-bottom: 14px;
    border-bottom: 2px solid var(--accent);
    letter-spacing: -0.01em;
    color: var(--accent);
}
.markdown-body h2 {
    font-size: 23px;
    margin: 48px 0 16px 0;
    letter-spacing: -0.005em;
    border-bottom: none;
    padding-bottom: 0;
}
.markdown-body h2::before {
    content: "§ ";
    color: var(--accent);
    font-weight: 700;
    font-family: var(--font-serif);
}
.markdown-body h3 {
    font-size: 17.5px;
    margin: 32px 0 12px 0;
    color: var(--fg-bright);
}
.markdown-body h4 {
    font-size: 15px;
    margin: 24px 0 10px 0;
    color: var(--fg-soft);
}

.markdown-body p { margin: 14px 0; }
.markdown-body strong { font-weight: 600; color: var(--fg-bright); }
.markdown-body em { font-style: normal; color: var(--accent); font-weight: 500; }

.markdown-body ul, .markdown-body ol {
    padding-left: 28px;
    margin: 14px 0;
}
.markdown-body li { margin: 5px 0; }
.markdown-body li > p { margin: 0.3em 0; }

.markdown-body hr {
    display: none;  /* '---' in markdown is purely a visual separator; the H2/H3 spacing is enough */
}

/* ============================================================
   TABLES (three-line academic style)
   ============================================================ */

.markdown-body table,
.markdown-body table.three-line {
    border-collapse: collapse;
    margin: 22px 0;
    width: 100%;
    font-size: 14.5px;
    line-height: 1.6;
    border: none;
    table-layout: auto;
    word-break: normal;
}
.markdown-body table.three-line {
    border-top: 2px solid var(--border-strong);
    border-bottom: 2px solid var(--border-strong);
}
.markdown-body table.three-line thead tr {
    border-bottom: 1.2px solid var(--border-strong);
    background: var(--bg-elev);
}
.markdown-body table.three-line th,
.markdown-body table.three-line td {
    border: none;
    padding: 9px 14px;
    text-align: left;
    vertical-align: top;
    overflow-wrap: anywhere;
    word-break: break-word;
    white-space: normal;
}
.markdown-body table.three-line th {
    font-weight: 700;
    color: var(--fg-bright);
    font-size: 13.5px;
    letter-spacing: 0.005em;
}
.markdown-body table.three-line tbody tr {
    border-bottom: 1px solid var(--border-soft);
}
.markdown-body table.three-line tbody tr:last-child {
    border-bottom: none;
}
.markdown-body table.three-line tbody tr:hover {
    background: var(--bg-elev);
}
.markdown-body table.three-line code {
    overflow-wrap: anywhere;
    word-break: break-all;
    white-space: normal;
}

/* ============================================================
   CODE
   ============================================================ */

.markdown-body code {
    font-family: var(--font-mono);
    background: rgba(139, 21, 56, 0.06);
    color: var(--accent);
    padding: 1.5px 6px;
    border-radius: 3px;
    font-size: 0.86em;
    border: 1px solid rgba(139, 21, 56, 0.08);
}

.markdown-body pre {
    background: var(--bg-code);
    border: 1px solid var(--border-soft);
    border-radius: 5px;
    padding: 16px 22px;
    overflow-x: auto;
    line-height: 1.6;
    font-size: 13px;
    margin: 18px 0;
    box-shadow: 0 1px 2px rgba(0,0,0,0.02);
    white-space: pre;
}
.markdown-body pre code {
    padding: 0;
    background: transparent;
    color: var(--code-default);
    font-size: inherit;
    border-radius: 0;
    border: none;
    font-weight: 400;
}

/* Pygments syntax tokens — paper light */
.codehilite .k, .codehilite .kd, .codehilite .kn, .codehilite .kr,
.codehilite .o, .codehilite .ow { color: var(--code-keyword); font-weight: 500; }
.codehilite .s, .codehilite .s1, .codehilite .s2, .codehilite .sb { color: var(--code-string); }
.codehilite .c, .codehilite .c1, .codehilite .cm { color: var(--code-comment); font-style: italic; }
.codehilite .nb, .codehilite .nf, .codehilite .nc { color: var(--code-fn); }
.codehilite .mi, .codehilite .mf { color: var(--code-num); }
.codehilite .n  { color: var(--code-default); }
.codehilite .nd { color: var(--code-num); }
.codehilite .nt { color: var(--code-string); }

/* ============================================================
   MERMAID
   ============================================================ */

pre.mermaid, .mermaid {
    background: var(--bg-elev);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius);
    padding: 22px 18px;
    margin: 22px 0;
    text-align: center;
    overflow-x: auto;
    box-shadow: 0 1px 2px rgba(0,0,0,0.02);
    /* Hide raw text until mermaid renders */
    color: transparent;
    font-size: 0;
}
pre.mermaid svg, .mermaid svg {
    max-width: 100%;
    height: auto;
    font-size: 14px;
}

/* ============================================================
   BLOCKQUOTES & CALLOUTS
   ============================================================ */

.markdown-body blockquote {
    margin: 22px 0;
    padding: 10px 18px;
    border-left: 3px solid var(--accent);
    background: var(--bg-elev);
    color: var(--fg-soft);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    font-style: normal;
}
.markdown-body blockquote > :first-child { margin-top: 0; }
.markdown-body blockquote > :last-child { margin-bottom: 0; }

/* Lesson-meta callout (章首导读: 谁该读 / 前置阅读 / 耗时 / 学完能) */
.markdown-body blockquote.lesson-meta {
    border-left: 4px solid #a86420;
    background: linear-gradient(0deg, rgba(168,100,32,0.05), rgba(168,100,32,0.05)), var(--bg-elev);
    border-radius: var(--radius);
    padding: 14px 22px;
    margin: 18px 0 26px 0;
    color: var(--fg);
    font-size: 14.5px;
    font-style: normal;
}
.markdown-body blockquote.lesson-meta strong {
    color: #a86420;
}

/* Optional custom callouts (use in markdown via raw HTML) */
.callout {
    border-left: 4px solid var(--info);
    background: var(--info-bg);
    padding: 14px 20px;
    margin: 22px 0;
    border-radius: 0 5px 5px 0;
    font-size: 15px;
    color: var(--fg);
}
.callout.warn { border-left-color: var(--warn); background: var(--warn-bg); }
.callout.good { border-left-color: var(--good); background: var(--good-bg); }
.callout.tip  { border-left-color: var(--accent); background: var(--tip-bg); }
.callout.research { border-left-color: var(--research); background: var(--research-bg); }
.callout .label {
    font-weight: 700;
    text-transform: uppercase;
    font-size: 10.5px;
    letter-spacing: 1.4px;
    color: var(--info);
    display: block;
    margin-bottom: 6px;
}
.callout.warn .label { color: var(--warn); }
.callout.good .label { color: var(--good); }
.callout.tip  .label { color: var(--accent); }
.callout.research .label { color: var(--research); }
.callout p:first-child { margin-top: 0; }
.callout p:last-child { margin-bottom: 0; }

/* ============================================================
   MATH (KaTeX)
   ============================================================ */

.markdown-body .math-display {
    display: block;
    margin: 22px 0;
    text-align: center;
    overflow-x: auto;
}
.markdown-body .math-display .katex-display { margin: 0; }
.markdown-body .math-inline { white-space: nowrap; }

/* ============================================================
   PAGE NAV (prev / next)
   ============================================================ */

.page-nav {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin-top: 72px;
    font-size: 13.5px;
}
.page-nav a {
    padding: 14px 18px;
    background: var(--bg-elev);
    border: 1px solid var(--border-soft);
    border-radius: var(--radius);
    color: var(--fg);
    line-height: 1.5;
    transition: border-color 0.15s, background 0.15s;
}
.page-nav a:hover {
    border-color: var(--accent);
    background: var(--tip-bg);
    color: var(--fg-bright);
}
.page-nav .label {
    display: block;
    font-size: 10.5px;
    color: var(--fg-dim);
    text-transform: uppercase;
    letter-spacing: 1.4px;
    margin-bottom: 3px;
    font-weight: 700;
}
.page-nav .title { font-weight: 600; }
.page-nav a.prev .title::before { content: "← "; color: var(--accent); }
.page-nav a.next { text-align: right; }
.page-nav a.next .title::after { content: " →"; color: var(--accent); }
.page-nav .placeholder {
    background: transparent;
    border: 1px dashed transparent;
}

/* ============================================================
   MISC
   ============================================================ */

.markdown-body img { max-width: 100%; height: auto; }
.markdown-body kbd {
    padding: 2px 6px;
    font-size: 12px;
    font-family: var(--font-mono);
    background: var(--bg-elev-2);
    border: 1px solid var(--border);
    border-radius: 3px;
    box-shadow: 0 1px 0 var(--border);
}

::selection { background: var(--tip-bg); color: var(--fg-bright); }

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: var(--fg-dim); }