/* =============================================================
   Peptide.ST Education, docs UI (Claude-Code-Docs-style layout)
   Three columns: left sidebar · content · "On this page" rail.
   Brand: dark theme, accent #7c85ff, Outfit display + Space Grotesk.
   ============================================================= */

:root {
  --bg: #000000;
  --bg-2: #07070b;
  --panel: rgba(255,255,255,0.02);
  --border: rgba(255,255,255,0.08);
  --border-2: rgba(255,255,255,0.06);
  --text: #ffffff;
  --muted: #8a8a93;
  --muted-2: #b6b7c2;
  --accent: #7c85ff;
  --accent-soft: rgba(124,133,255,0.10);
  --accent-line: rgba(124,133,255,0.35);
  --amber: #ff9900;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --hdr: 113px;       /* full header: bar + tabs */
  --bar: 65px;        /* brand bar only (height + border) */
  --sidebar-w: 290px;
  --toc-w: 240px;
  --content-max: 820px;
}

* { margin: 0; padding: 0; box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

/* Overscroll rubber-band wrapper. NB: no static will-change/transform here so it never
   becomes a containing block for the fixed mobile drawer (transform is applied transiently by JS). */
#docViewport.springing { transition: transform 0.55s cubic-bezier(0.16, 1, 0.3, 1); }
html.doc-locked { overflow: hidden; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
  -webkit-font-smoothing: antialiased;
  line-height: 1.6;
}
a { color: inherit; text-decoration: none; }
::selection { background: rgba(124,133,255,0.3); }

/* focus visibility (WCAG 2.4.7) */
a:focus-visible, button:focus-visible, input:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ================= TOP BAR ================= */
.doc-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(4,4,6,0.86);
  backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}
.doc-bar {
  display: flex; align-items: center; gap: 24px;
  height: 64px; padding: 0 26px;
  border-bottom: 1px solid var(--border-2);
}
.doc-brand { display: flex; align-items: center; gap: 1px; flex-shrink: 0; }
.doc-brand .logo { font-size: 1.2rem; font-weight: 500; color: #fff; letter-spacing: -0.01em; }
.doc-brand .logo span { color: var(--accent); }
.doc-brand .tag { font-size: 1.2rem; font-weight: 400; color: var(--muted); letter-spacing: -0.01em; }
.doc-search-trigger {
  display: inline-flex; align-items: center; justify-content: center;
  width: 40px; height: 40px; padding: 0; margin-left: auto;
  border: 1px solid var(--border); background: rgba(255,255,255,0.03); color: var(--muted);
  font-family: inherit; cursor: pointer; flex-shrink: 0;
  transition: border-color .25s, background .25s, color .25s;
}
.doc-search-trigger:hover { color: #fff; border-color: var(--accent-line); background: rgba(124,133,255,0.05); }
.doc-search-trigger i { font-size: 1.25rem; }
.doc-search-trigger .st-text, .doc-search-trigger .kbd { display: none; }
.doc-bar-links { display: flex; align-items: center; gap: 4px; flex-shrink: 0; }
.doc-bar-links a { padding: 8px 14px; font-size: 0.88rem; color: var(--muted-2); transition: color .25s; }
.doc-bar-links a:hover { color: #fff; }
.doc-bar-links a.cta { color: #000; background: #fff; transition: all .3s var(--ease); }
.doc-bar-links a.cta:hover { background: var(--accent); color: #fff; }

/* tabs row */
.doc-tabs { display: flex; align-items: center; gap: 4px; height: 48px; padding: 0 12px; overflow-x: auto; scrollbar-width: none; }
.doc-tabs::-webkit-scrollbar { display: none; }
.doc-tab {
  position: relative; padding: 0 14px; height: 48px; display: inline-flex; align-items: center;
  font-size: 0.9rem; font-weight: 500; color: var(--muted); white-space: nowrap; transition: color .25s;
}
.doc-tab:hover { color: #fff; }
.doc-tab.active { color: #fff; }
.doc-tab.active::after {
  content: ''; position: absolute; left: 14px; right: 14px; bottom: -1px; height: 2px; background: var(--accent);
}

/* ================= LAYOUT SHELL ================= */
.doc-shell {
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr) var(--toc-w);
  max-width: 1600px; margin: 0 auto;
  padding-top: var(--hdr);
}

/* ================= SIDEBAR ================= */
.doc-sidebar {
  position: sticky; top: var(--hdr); align-self: start;
  height: calc(100vh - var(--hdr));
  overflow-y: auto; padding: 30px 18px 60px 26px;
  border-right: 1px solid var(--border);
  scrollbar-width: thin; scrollbar-color: rgba(255,255,255,0.12) transparent;
}
.doc-sidebar::-webkit-scrollbar { width: 8px; }
.doc-sidebar::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 0; }
.sb-group { margin-bottom: 28px; }
.sb-group h4 {
  font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.13em; font-weight: 600;
  color: var(--muted); margin-bottom: 12px; padding-left: 12px;
}
.sb-link {
  display: block; padding: 7px 12px; font-size: 0.9rem; color: var(--muted-2);
  border-left: 2px solid transparent; transition: color .2s, border-color .2s, background .2s;
}
.sb-link:hover { color: #fff; }
.sb-link.active { color: #fff; border-left-color: var(--accent); background: var(--accent-soft); }

/* ================= CONTENT ================= */
.doc-main { min-width: 0; padding: 44px 56px 80px; }
.doc-content { max-width: var(--content-max); }
.breadcrumb { display: flex; align-items: center; gap: 8px; font-size: 0.8rem; color: var(--muted); margin-bottom: 22px; flex-wrap: wrap; }
.breadcrumb a { color: var(--muted); transition: color .2s; }
.breadcrumb a:hover { color: #fff; }
.breadcrumb i { font-size: 0.85rem; opacity: 0.6; }
.breadcrumb .crumb-current { color: var(--muted-2); }
.eyebrow { display: inline-block; color: var(--accent); text-transform: uppercase; letter-spacing: 0.18em; font-size: 0.72rem; font-weight: 600; margin-bottom: 14px; }

.doc-content h1 {
  font-family: 'Outfit', 'DM Sans', sans-serif; font-size: clamp(2.1rem, 4vw, 3rem);
  font-weight: 600; letter-spacing: -0.035em; line-height: 1.08; margin-bottom: 16px;
}
.doc-content .lead { font-size: 1.15rem; line-height: 1.7; color: var(--muted-2); margin-bottom: 28px; }
.doc-content h2 {
  font-family: 'Outfit', sans-serif; font-size: 1.6rem; font-weight: 500; letter-spacing: -0.02em;
  margin: 52px 0 16px; padding-top: 16px; scroll-margin-top: calc(var(--hdr) + 20px);
}
.doc-content h3 {
  font-family: 'Outfit', sans-serif; font-size: 1.2rem; font-weight: 500; letter-spacing: -0.01em;
  margin: 32px 0 12px; scroll-margin-top: calc(var(--hdr) + 20px);
}
.doc-content h2 .ah, .doc-content h3 .ah { opacity: 0; margin-left: 10px; color: var(--accent); font-size: 0.7em; transition: opacity .2s; }
.doc-content h2:hover .ah, .doc-content h3:hover .ah { opacity: 1; }
.doc-content p { color: rgba(255,255,255,0.74); font-size: 1rem; line-height: 1.75; margin: 14px 0; }
.doc-content a.inline { color: #cfd3ff; border-bottom: 1px solid var(--accent-line); transition: color .2s, border-color .2s; }
.doc-content a.inline:hover { color: #fff; border-color: #fff; }
.doc-content ul, .doc-content ol { margin: 14px 0 14px 4px; padding-left: 22px; color: rgba(255,255,255,0.74); }
.doc-content li { margin: 8px 0; line-height: 1.7; }
.doc-content li::marker { color: var(--accent); }
.doc-content strong, .doc-content b { color: #fff; font-weight: 600; }
.doc-content hr { border: none; border-top: 1px solid var(--border); margin: 40px 0; }

/* content components (shared with the rest of the site vocabulary) */
.callout { display: flex; gap: 15px; padding: 18px 20px; border: 1px solid var(--border); background: var(--panel); margin: 22px 0; }
.callout i { font-size: 1.25rem; flex-shrink: 0; margin-top: 2px; }
.callout.note i { color: var(--accent); }
.callout.warn { border-color: rgba(255,153,0,0.22); background: rgba(255,153,0,0.05); }
.callout.warn i { color: var(--amber); }
.callout h5 { font-family: 'Outfit', sans-serif; font-size: 1rem; font-weight: 500; margin-bottom: 5px; }
.callout p { color: rgba(255,255,255,0.62); font-size: 0.92rem; line-height: 1.6; margin: 0; }
.callout a { color: #cfd3ff; border-bottom: 1px solid var(--accent-line); }

.formula { font-family: 'Outfit', sans-serif; color: #e8e9ff; background: var(--accent-soft); border: 1px solid var(--accent-line); padding: 14px 18px; font-size: 1.02rem; display: block; margin: 18px 0; }

.math-card { border: 1px solid var(--accent-line); background: rgba(124,133,255,0.04); padding: 22px 24px; margin: 16px 0; }
.math-card .mc-label { color: var(--accent); font-size: 0.7rem; text-transform: uppercase; letter-spacing: 0.14em; font-weight: 600; margin-bottom: 12px; }
.math-card .mc-row { display: flex; justify-content: space-between; gap: 16px; padding: 8px 0; border-bottom: 1px dashed rgba(255,255,255,0.08); font-size: 0.94rem; }
.math-card .mc-row:last-of-type { border-bottom: none; }
.math-card .mc-row span { color: rgba(255,255,255,0.6); }
.math-card .mc-row b { color: #fff; font-weight: 500; font-family: 'Outfit', sans-serif; }
.math-card .mc-result { margin-top: 12px; padding-top: 14px; border-top: 1px solid var(--accent-line); display: flex; justify-content: space-between; align-items: baseline; gap: 16px; }
.math-card .mc-result span { color: #cfd3ff; font-size: 0.88rem; }
.math-card .mc-result b { font-family: 'Outfit', sans-serif; font-size: 1.4rem; color: #fff; font-weight: 600; }

.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 18px 0; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin: 18px 0; }
.info-card { border: 1px solid var(--border); background: var(--panel); padding: 22px 22px; transition: all .4s var(--ease); }
.info-card:hover { border-color: var(--accent-line); background: rgba(124,133,255,0.035); transform: translateY(-3px); }
.info-card .ic-top { display: flex; align-items: center; gap: 11px; margin-bottom: 10px; }
.info-card .ic-icon { width: 36px; height: 36px; flex-shrink: 0; border: 1px solid var(--accent-line); background: var(--accent-soft); display: flex; align-items: center; justify-content: center; color: var(--accent); }
.info-card .ic-icon i { font-size: 18px; }
.info-card h4 { font-family: 'Outfit', sans-serif; font-size: 1.05rem; font-weight: 500; }
.info-card p { color: rgba(255,255,255,0.58); font-size: 0.9rem; line-height: 1.6; margin: 0; }

.table-wrap { border: 1px solid var(--border); overflow-x: auto; margin: 20px 0; }
table.edu-table { width: 100%; border-collapse: collapse; min-width: 560px; }
table.edu-table th, table.edu-table td { text-align: left; padding: 12px 16px; font-size: 0.9rem; border-bottom: 1px solid var(--border-2); }
table.edu-table thead th { color: rgba(255,255,255,0.55); font-weight: 500; text-transform: uppercase; letter-spacing: 0.07em; font-size: 0.7rem; background: rgba(255,255,255,0.02); }
table.edu-table tbody tr:hover { background: rgba(124,133,255,0.045); }
table.edu-table tbody tr:last-child td { border-bottom: none; }
table.edu-table td.t-name { color: #fff; font-weight: 500; }
table.edu-table td.t-mw { font-family: 'Outfit', sans-serif; color: #cfd3ff; }

.pill { display: inline-block; padding: 3px 9px; font-size: 0.7rem; letter-spacing: 0.02em; border: 1px solid var(--border); color: rgba(255,255,255,0.65); white-space: nowrap; }
.pill.in { color: #9ff0c4; border-color: rgba(80,220,150,0.3); background: rgba(80,220,150,0.07); }
.pill.soon { color: #ffd9a3; border-color: rgba(255,153,0,0.3); background: rgba(255,153,0,0.07); }
.pill.ref { color: rgba(255,255,255,0.5); }

.steps { display: flex; flex-direction: column; position: relative; margin: 18px 0; }
.steps::before { content: ''; position: absolute; left: 19px; top: 26px; bottom: 26px; width: 1px; background: linear-gradient(180deg, transparent, var(--accent-line), transparent); }
.step { display: grid; grid-template-columns: 40px 1fr; gap: 20px; padding: 16px 0; }
.step-dot { width: 40px; height: 40px; border: 1px solid var(--accent-line); background: #000; display: flex; align-items: center; justify-content: center; font-family: 'Outfit', sans-serif; font-weight: 500; color: var(--accent); z-index: 1; }
.step-body h4 { font-family: 'Outfit', sans-serif; font-size: 1.05rem; font-weight: 500; margin-bottom: 5px; }
.step-body p { color: rgba(255,255,255,0.6); font-size: 0.93rem; line-height: 1.6; margin: 0; }

/* tool / next-step link cards */
.link-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin: 20px 0; }
.link-card { display: flex; flex-direction: column; gap: 8px; padding: 20px; border: 1px solid var(--border); background: var(--panel); transition: all .4s var(--ease); }
.link-card:hover { border-color: var(--accent-line); background: rgba(124,133,255,0.04); transform: translateY(-3px); }
.link-card i.lc { color: var(--accent); font-size: 1.5rem; }
.link-card h4 { font-family: 'Outfit', sans-serif; font-size: 1rem; font-weight: 500; }
.link-card p { color: rgba(255,255,255,0.55); font-size: 0.85rem; margin: 0; line-height: 1.5; }
.link-card .go { color: var(--accent); font-size: 0.82rem; font-weight: 500; display: inline-flex; align-items: center; gap: 6px; }
.link-card .go i { transition: transform .3s var(--ease); }
.link-card:hover .go i { transform: translateX(4px); }

/* prev / next pager */
.doc-pager { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 64px; padding-top: 32px; border-top: 1px solid var(--border); }
.pager-link { display: flex; flex-direction: column; gap: 6px; padding: 18px 22px; border: 1px solid var(--border); transition: all .35s var(--ease); }
.pager-link:hover { border-color: var(--accent-line); background: rgba(124,133,255,0.04); }
.pager-link.next { text-align: right; align-items: flex-end; }
.pager-link .pl-dir { font-size: 0.75rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.1em; }
.pager-link .pl-title { font-family: 'Outfit', sans-serif; color: #fff; font-size: 1.02rem; font-weight: 500; }
.pager-link.empty { visibility: hidden; }

/* page-foot disclaimer */
.doc-foot { margin-top: 48px; padding-top: 22px; border-top: 1px solid var(--border-2); display: flex; gap: 14px; align-items: flex-start; }
.doc-foot i { color: var(--amber); font-size: 1.1rem; flex-shrink: 0; margin-top: 2px; }
.doc-foot p { color: var(--muted); font-size: 0.8rem; line-height: 1.6; margin: 0; }

/* ================= ON THIS PAGE (TOC) ================= */
.doc-toc { position: sticky; top: var(--hdr); align-self: start; height: calc(100vh - var(--hdr)); overflow-y: auto; padding: 44px 26px 60px 18px; scrollbar-width: none; }
.doc-toc::-webkit-scrollbar { display: none; }
.toc-head { display: flex; align-items: center; gap: 8px; font-size: 0.74rem; text-transform: uppercase; letter-spacing: 0.13em; color: var(--muted); font-weight: 600; margin-bottom: 16px; }
.toc-head i { font-size: 1rem; }
.toc-list { position: relative; }
.toc-rail { position: absolute; left: 0; top: 0; bottom: 0; width: 2px; background: var(--border); }
.toc-rail-fill { position: absolute; left: 0; top: 0; width: 2px; height: 0; background: var(--accent); transition: height .15s linear; }
.toc-link { display: block; padding: 6px 0 6px 16px; font-size: 0.84rem; line-height: 1.4; color: var(--muted); transition: color .2s; }
.toc-link.lvl-3 { padding-left: 30px; font-size: 0.8rem; }
.toc-link:hover { color: #fff; }
.toc-link.active { color: var(--accent); }
.toc-empty { color: var(--muted); font-size: 0.82rem; }

/* ================= MOBILE ================= */
.doc-menu-btn { display: none; background: none; border: 1px solid var(--border); color: #fff; width: 40px; height: 40px; align-items: center; justify-content: center; cursor: pointer; flex-shrink: 0; }
.doc-menu-btn i { font-size: 1.35rem; }
.doc-scrim { display: none; position: fixed; inset: var(--bar) 0 0 0; background: rgba(0,0,0,0.55); z-index: 96; opacity: 0; transition: opacity .3s; }
.doc-scrim.show { display: block; opacity: 1; }

@media (max-width: 1200px) {
  .doc-shell { grid-template-columns: var(--sidebar-w) minmax(0,1fr); }
  .doc-toc { display: none; }
}
@media (max-width: 920px) {
  .doc-shell { grid-template-columns: minmax(0,1fr); }
  .doc-main { padding: 28px 22px 70px; }
  .doc-menu-btn { display: inline-flex; }
  .doc-bar-links { display: none; }
  .doc-sidebar {
    position: fixed; top: var(--bar); left: 0; right: 0; bottom: 0; width: 100%; max-width: none;
    background: #060608; z-index: 101; transform: translateX(-100%);
    transition: transform .35s var(--ease); overscroll-behavior: contain;
    height: calc(100vh - var(--bar)); padding: 24px 22px 80px;
  }
  .doc-sidebar.open { transform: translateX(0); }
}
@media (max-width: 720px) {
  .grid-2, .grid-3, .link-cards, .doc-pager { grid-template-columns: 1fr; }
  .pager-link.next { text-align: left; align-items: flex-start; }
  .doc-content { overflow-wrap: break-word; }
}
@media (max-width: 560px) {
  .doc-bar { gap: 10px; padding: 0 14px; }
  .doc-tabs { padding: 0 14px; }
}

/* compound-library controls (reference/library page) */
.lib-controls { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; margin: 20px 0 18px; }
.lib-search2 { flex: 1 1 220px; display: flex; align-items: center; gap: 9px; border: 1px solid var(--border); background: rgba(255,255,255,0.02); padding: 9px 14px; }
.lib-search2:focus-within { border-color: var(--accent-line); }
.lib-search2 i { color: var(--muted); font-size: 1.05rem; }
.lib-search2 input { flex: 1; background: none; border: none; outline: none; color: #fff; font-family: inherit; font-size: 0.92rem; }
.lib-search2 input::placeholder { color: var(--muted); }
.lib-filters { display: flex; gap: 7px; flex-wrap: wrap; }
.lib-filters button { padding: 8px 13px; font-family: inherit; font-size: 0.82rem; font-weight: 500; color: var(--muted); background: none; border: 1px solid var(--border); cursor: pointer; transition: all .25s var(--ease); }
.lib-filters button:hover { color: #fff; }
.lib-filters button.active { color: #fff; border-color: var(--accent-line); background: var(--accent-soft); }
.lib-empty2 { text-align: center; color: var(--muted); padding: 24px; font-size: 0.9rem; }

/* prev/next pager arrows */
.pl-dir { display: inline-flex; align-items: center; gap: 5px; }
.pl-dir i { font-size: 1.05rem; }

/* ================= FULL-SCREEN SEARCH OVERLAY ================= */
.search-overlay {
  position: fixed; inset: 0; z-index: 200; display: flex; justify-content: center; align-items: flex-start;
  padding: 12vh 20px 20px; background: rgba(3,3,5,0.72);
  backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
  opacity: 0; visibility: hidden; transition: opacity .3s var(--ease), visibility 0s linear .3s;
}
.search-overlay.open { opacity: 1; visibility: visible; transition: opacity .3s var(--ease); }
.search-modal {
  width: 100%; max-width: 640px; background: #0a0a0f; border: 1px solid var(--border);
  box-shadow: 0 40px 90px rgba(0,0,0,0.7);
  transform: translateY(-14px) scale(0.97); opacity: 0;
  transition: transform .35s var(--ease), opacity .35s var(--ease);
}
.search-overlay.open .search-modal { transform: none; opacity: 1; }
.search-modal-bar { display: flex; align-items: center; gap: 12px; padding: 15px 16px; border-bottom: 1px solid var(--border); }
.search-modal-bar > i { font-size: 1.3rem; color: var(--accent); }
.search-modal-bar input { flex: 1; background: none; border: none; outline: none; color: #fff; font-family: inherit; font-size: 1.05rem; }
.search-modal-bar input::placeholder { color: var(--muted); }
.search-close { background: none; border: 1px solid var(--border); color: var(--muted); width: 30px; height: 30px; display: flex; align-items: center; justify-content: center; cursor: pointer; flex-shrink: 0; font-size: 1.1rem; }
.search-close:hover { color: #fff; border-color: var(--accent-line); }
.search-results { max-height: 56vh; overflow-y: auto; }
.search-results a { display: flex; flex-direction: column; gap: 3px; padding: 12px 18px; border-bottom: 1px solid var(--border-2); }
.search-results a:last-child { border-bottom: none; }
.search-results a:hover, .search-results a.sel { background: var(--accent-soft); }
.search-results .sr-title { color: #fff; font-size: 0.96rem; }
.search-results .sr-crumb { color: var(--muted); font-size: 0.76rem; }
.search-results .sr-empty, .search-results .sr-hint { padding: 18px; color: var(--muted); font-size: 0.88rem; }