:root {
  --brand: #402FFF;
  --brand-hover: #3020E0;
  --ink: #1B1C21;
  --ink-2: #2D2E37;
  --muted: #5F626E;
  --canvas: #EDEDED;
  --surface: #FFFFFF;
  --surface-2: #F6F6F8;
  --border: #D8D9E0;
  --urgent: #EC1D35;
  --success: #12754E;
  --font: Inter, "Inter Variable", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --top: 56px;
  --sidebar: 288px;
  --toc: 240px;
}
* { box-sizing: border-box; }
html { scroll-padding-top: calc(var(--top) + 16px); }
body {
  margin: 0; background: var(--canvas); color: var(--ink); font-family: var(--font);
  font-size: 16px; line-height: 1.6; -webkit-font-smoothing: antialiased;
}
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-hover); text-decoration: underline; }
code, pre, kbd { font-family: var(--mono); font-size: 0.9em; }

/* top bar */
.top {
  position: fixed; inset: 0 0 auto 0; height: var(--top); z-index: 40;
  display: flex; align-items: center; gap: 16px; padding: 0 16px;
  background: var(--ink); color: #fff; border-bottom: 1px solid #2D2E37;
}
.brand { color: #fff; font-weight: 700; letter-spacing: -0.01em; white-space: nowrap; display: flex; align-items: baseline; gap: 8px; }
.brand span { font-weight: 500; font-size: 12px; color: #B9BAC4; font-family: var(--mono); text-transform: uppercase; letter-spacing: 0.06em; }
.brand:hover { text-decoration: none; color: #fff; }
.menu-btn { display: none; width: 36px; height: 36px; border: 0; background: transparent; cursor: pointer; flex-direction: column; justify-content: center; gap: 5px; padding: 6px; }
.menu-btn span { display: block; height: 2px; background: #fff; border-radius: 2px; }
.search { position: relative; flex: 1; max-width: 520px; }
.search input {
  width: 100%; height: 36px; border-radius: 8px; border: 1px solid #3A3B45; background: #24252D; color: #fff;
  padding: 0 12px; font: inherit; font-size: 14px; outline: none;
}
.search input:focus { border-color: var(--brand); box-shadow: 0 0 0 3px rgba(64,47,255,.35); }
.search input::placeholder { color: #8A8C99; }
.search-results {
  position: absolute; top: 42px; left: 0; right: 0; background: var(--surface); color: var(--ink);
  border: 1px solid var(--border); border-radius: 10px; box-shadow: 0 16px 40px rgba(0,0,0,.18);
  max-height: 70vh; overflow: auto; padding: 6px;
}
.search-results a { display: block; padding: 8px 10px; border-radius: 8px; color: var(--ink); }
.search-results a:hover, .search-results a.focus { background: var(--surface-2); text-decoration: none; }
.search-results .r-title { font-weight: 600; font-size: 14px; }
.search-results .r-group { font-size: 11px; color: var(--muted); font-family: var(--mono); text-transform: uppercase; letter-spacing: .04em; }
.search-results .r-snippet { font-size: 13px; color: var(--muted); }
.search-results mark { background: rgba(64,47,255,.15); color: inherit; padding: 0 1px; border-radius: 2px; }
.search-results .r-empty { padding: 10px; color: var(--muted); font-size: 14px; }
.top-links { margin-left: auto; display: flex; gap: 4px; }
.top-links a { color: #D9DAE3; font-size: 13px; padding: 6px 10px; border-radius: 6px; }
.top-links a:hover { background: #2D2E37; color: #fff; text-decoration: none; }

/* layout */
.layout { display: grid; grid-template-columns: var(--sidebar) minmax(0, 1fr) var(--toc); padding-top: var(--top); min-height: 100vh; }
.sidebar {
  position: sticky; top: var(--top); height: calc(100vh - var(--top)); overflow: auto;
  background: var(--surface); border-right: 1px solid var(--border); padding: 20px 16px 40px;
}
.nav-group { margin-bottom: 18px; }
.nav-group h2 { font-size: 11px; font-family: var(--mono); text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin: 0 0 6px 10px; font-weight: 600; }
.nav-group ul { list-style: none; margin: 0; padding: 0; }
.nav-group a { display: block; padding: 6px 10px; border-radius: 8px; color: var(--ink-2); font-size: 14px; line-height: 1.35; }
.nav-group a:hover { background: var(--surface-2); text-decoration: none; }
.nav-group a.active { background: rgba(64,47,255,.1); color: var(--brand); font-weight: 600; }

.content { padding: 32px 48px 64px; min-width: 0; }
.page { max-width: 880px; background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 40px 48px; }
.toc { position: sticky; top: var(--top); height: calc(100vh - var(--top)); overflow: auto; padding: 28px 16px; font-size: 13px; }
.toc-title { font-family: var(--mono); font-size: 11px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin-bottom: 8px; }
.toc ul { list-style: none; margin: 0; padding: 0 0 0 10px; border-left: 1px solid var(--border); }
.toc ul ul { border: 0; padding-left: 12px; }
.toc li { margin: 3px 0; }
.toc a { color: var(--muted); display: block; line-height: 1.35; }
.toc a:hover { color: var(--brand); text-decoration: none; }

/* article typography */
.page h1 { font-size: 32px; line-height: 1.2; letter-spacing: -0.02em; margin: 0 0 20px; font-weight: 700; }
.page h2 { font-size: 22px; line-height: 1.3; letter-spacing: -0.01em; margin: 40px 0 12px; padding-top: 12px; border-top: 1px solid var(--border); font-weight: 700; }
.page h3 { font-size: 17px; margin: 28px 0 8px; font-weight: 600; }
.page h4 { font-size: 15px; margin: 20px 0 6px; font-weight: 600; }
.page p, .page ul, .page ol { margin: 0 0 14px; }
.page li { margin: 4px 0; }
.page li > ul, .page li > ol { margin-bottom: 0; }
.page strong { font-weight: 600; }
.page hr { border: 0; border-top: 1px solid var(--border); margin: 28px 0; }
.page blockquote { margin: 0 0 14px; padding: 8px 16px; border-left: 3px solid var(--brand); background: var(--surface-2); color: var(--ink-2); border-radius: 0 8px 8px 0; }
.page code { background: var(--surface-2); border: 1px solid var(--border); border-radius: 4px; padding: 1px 5px; font-size: 0.85em; color: var(--ink-2); }
.page pre { background: #101216; color: #E6E7EC; border-radius: 10px; padding: 14px 16px; overflow: auto; font-size: 13px; line-height: 1.5; margin: 0 0 16px; }
.page pre code { background: transparent; border: 0; padding: 0; color: inherit; font-size: inherit; }
.page pre.mermaid { background: var(--surface-2); color: var(--ink); border: 1px solid var(--border); text-align: center; padding: 12px; }
.page pre.mermaid svg { max-width: 100%; height: auto; }
.page .table-wrap, .page table { max-width: 100%; }
.page table { border-collapse: collapse; width: 100%; margin: 0 0 18px; font-size: 14px; display: block; overflow-x: auto; }
.page thead th { text-align: left; background: var(--surface-2); font-family: var(--mono); font-size: 11px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); }
.page th, .page td { border: 1px solid var(--border); padding: 8px 10px; vertical-align: top; }
.page td:first-child { white-space: nowrap; }
.page td:first-child:has(> a:only-child) { white-space: normal; }
.page img { max-width: 100%; height: auto; display: block; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-2); }
.page .img-link { display: block; margin: 8px 0 12px; }
.page .img-link:hover img { border-color: var(--brand); }
.page video { max-width: 100%; border-radius: 10px; display: block; margin-bottom: 14px; }
.page .presentation-frame { width: 100%; min-height: 280px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); display: block; margin-bottom: 14px; }
.page .button { display: inline-block; background: var(--brand); color: #fff; padding: 10px 18px; border-radius: 8px; font-weight: 600; }
.page .button:hover { background: var(--brand-hover); text-decoration: none; }

/* screens gallery (design/screens page) */
.page .screen-meta { font-family: var(--mono); font-size: 12px; color: var(--muted); margin: -4px 0 8px; letter-spacing: .02em; }
.page .screen-meta b { color: var(--ink-2); font-weight: 600; }
.page .screen-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; margin: 8px 0 18px; }
.page .screen-grid figure { margin: 0; }
.page .screen-grid img { max-height: 320px; object-fit: cover; object-position: top; width: 100%; }
.page .screen-grid figcaption { font-size: 13px; margin-top: 6px; line-height: 1.35; }

/* pager and footer */
.pager { max-width: 880px; display: flex; gap: 12px; margin-top: 20px; }
.pager a { flex: 1; background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 12px 16px; color: var(--ink); font-weight: 600; font-size: 14px; }
.pager a span { display: block; font-weight: 500; font-size: 11px; color: var(--muted); font-family: var(--mono); text-transform: uppercase; letter-spacing: .06em; margin-bottom: 4px; }
.pager a.next { text-align: right; margin-left: auto; }
.pager a:hover { border-color: var(--brand); text-decoration: none; }
.page-footer { max-width: 880px; display: flex; flex-wrap: wrap; gap: 8px 24px; margin-top: 24px; font-size: 12px; color: var(--muted); font-family: var(--mono); }

/* responsive */
@media (max-width: 1280px) {
  .layout { grid-template-columns: var(--sidebar) minmax(0, 1fr); }
  .toc { display: none; }
}
@media (max-width: 960px) {
  .layout { grid-template-columns: minmax(0, 1fr); }
  .menu-btn { display: flex; }
  .top-links { display: none; }
  .sidebar {
    position: fixed; top: var(--top); left: 0; bottom: 0; width: min(var(--sidebar), 86vw); z-index: 30;
    transform: translateX(-105%); transition: transform .2s ease; box-shadow: 0 0 40px rgba(0,0,0,.25);
  }
  body.menu-open .sidebar { transform: none; }
  .scrim { display: none; position: fixed; inset: var(--top) 0 0 0; background: rgba(27,28,33,.45); z-index: 20; }
  body.menu-open .scrim { display: block; }
  .content { padding: 20px 16px 48px; }
  .page { padding: 24px 20px; border-radius: 12px; }
  .page h1 { font-size: 26px; }
  .page td:first-child { white-space: normal; }
}
@media (max-width: 600px) {
  .search { max-width: none; }
  .brand span { display: none; }
  .page { padding: 20px 16px; }
  .pager { flex-direction: column; }
}

/* inline PDF preview on /presentation */
.page object.pdf-preview { display: block; width: 100%; height: 640px; border: 1px solid var(--border); border-radius: 10px; background: var(--surface-2); margin: 8px 0 18px; }
@media (max-width: 600px) { .page object.pdf-preview { height: 420px; } }