/* ═══════════════════════════════════════════════════════════════
   EduGraph — Shared Styles
   Extracted from al-math.html (base) + igcse-math.html (extras)
   ═══════════════════════════════════════════════════════════════ */

*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --bg: #08090e;
  --surface: rgba(12,14,24,0.94);
  --border: rgba(255,255,255,0.06);
  --text: #e8e4dc;
  --text2: #8a8697;
  --text3: #55516a;
  --gold: #ffc857;
  --topbar: 52px;
  --sidebar: 230px;
  --detail: 300px;
}
html, body { height: 100%; background: var(--bg); color: var(--text); font-family: 'DM Sans', sans-serif; font-size: 13px; overflow: hidden; }

/* Grain */
body::after { content: ''; position: fixed; inset: 0; opacity: 0.035; background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E"); pointer-events: none; z-index: 9999; }

/* Topbar */
.topbar { position: fixed; top: 0; left: 0; right: 0; height: var(--topbar); display: flex; align-items: center; justify-content: space-between; padding: 0 18px; background: rgba(8,9,14,0.92); backdrop-filter: blur(16px); border-bottom: 1px solid var(--border); z-index: 200; }
.topbar-left { display: flex; align-items: baseline; gap: 12px; }
.topbar h1 { font-family: 'Instrument Serif', serif; font-size: 22px; font-weight: 400; color: var(--gold); }
.topbar .sub { font-size: 10px; color: var(--text3); text-transform: uppercase; letter-spacing: 1px; }
.topbar-right { display: flex; align-items: center; gap: 6px; }
.stats { display: flex; gap: 14px; margin-right: 12px; }
.stat-n { font-family: 'Instrument Serif', serif; font-size: 17px; color: var(--gold); }
.stat-l { font-size: 9px; color: var(--text3); text-transform: uppercase; letter-spacing: 0.5px; margin-left: 3px; }
.nav-btn { background: rgba(255,255,255,0.04); border: 1px solid var(--border); color: var(--text2); padding: 4px 10px; border-radius: 5px; font-size: 10px; font-family: 'DM Sans', sans-serif; cursor: pointer; text-decoration: none; text-transform: uppercase; letter-spacing: 0.5px; transition: all 0.15s; }
.nav-btn:hover { background: rgba(255,200,87,0.08); border-color: rgba(255,200,87,0.15); color: var(--gold); }

/* Sidebar */
.sidebar { position: fixed; top: var(--topbar); left: 0; bottom: 0; width: var(--sidebar); background: var(--surface); border-right: 1px solid var(--border); overflow-y: auto; z-index: 100; padding: 12px; display: flex; flex-direction: column; gap: 10px; }
.sidebar::-webkit-scrollbar { width: 3px; }
.sidebar::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.08); border-radius: 2px; }
.sec-title { font-family: 'Instrument Serif', serif; font-size: 13px; margin-bottom: 6px; display: flex; align-items: center; gap: 6px; }
.sec-title::before { content: ''; width: 2px; height: 11px; background: var(--gold); border-radius: 1px; }

.search-box { width: 100%; padding: 7px 10px 7px 28px; background: rgba(255,255,255,0.04); border: 1px solid var(--border); border-radius: 6px; color: var(--text); font-family: 'DM Sans', sans-serif; font-size: 12px; outline: none; }
.search-box::placeholder { color: var(--text3); }
.search-box:focus { border-color: rgba(255,200,87,0.25); }
.search-wrap { position: relative; }
.search-wrap::before { content: '\2315'; position: absolute; left: 9px; top: 50%; transform: translateY(-50%); color: var(--text3); font-size: 13px; }

/* Sidebar Tabs */
.tab-bar { display: flex; gap: 0; margin-bottom: 8px; border-bottom: 1px solid var(--border); }
.tab-btn { flex: 1; background: none; border: none; border-bottom: 2px solid transparent; color: var(--text3); padding: 6px 4px; font-size: 10px; font-family: 'DM Sans', sans-serif; cursor: pointer; text-transform: uppercase; letter-spacing: 0.8px; transition: all 0.15s; }
.tab-btn:hover { color: var(--text2); }
.tab-btn.active { color: var(--gold); border-bottom-color: var(--gold); }
.tab-content { display: none; }
.tab-content.active { display: block; }

.book-btns { display: flex; gap: 3px; margin-bottom: 6px; }
.book-btn { flex: 1; background: rgba(255,255,255,0.03); border: 1px solid var(--border); color: var(--text3); padding: 3px; border-radius: 4px; font-size: 9px; font-family: 'DM Sans', sans-serif; cursor: pointer; text-transform: uppercase; letter-spacing: 0.5px; }
.book-btn:hover { color: var(--text2); }

/* Collapsible groups */
.group-header { display: flex; align-items: center; gap: 5px; padding: 5px 4px; cursor: pointer; user-select: none; border-radius: 4px; margin-top: 4px; transition: background 0.12s; }
.group-header:hover { background: rgba(255,255,255,0.03); }
.group-arrow { font-size: 8px; color: var(--text3); transition: transform 0.2s; width: 12px; text-align: center; }
.group-header.collapsed .group-arrow { transform: rotate(-90deg); }
.group-label { font-size: 10px; color: var(--text2); font-weight: 500; text-transform: uppercase; letter-spacing: 0.5px; flex: 1; }
.group-cnt { font-size: 9px; color: var(--text3); }
.group-body { overflow: hidden; transition: max-height 0.25s ease; }
.group-header.collapsed + .group-body { max-height: 0 !important; overflow: hidden; }

.book-list { display: flex; flex-direction: column; gap: 1px; }
.book-item { display: flex; align-items: center; gap: 6px; padding: 3px 5px 3px 16px; border-radius: 4px; cursor: pointer; transition: all 0.12s; user-select: none; }
.book-item:hover { background: rgba(255,255,255,0.03); }
.book-item.off { opacity: 0.2; }
.book-dot { width: 7px; height: 7px; border-radius: 50%; flex-shrink: 0; transition: transform 0.15s; }
.book-item:not(.off) .book-dot { box-shadow: 0 0 5px currentColor; }
.book-name { font-size: 10px; color: var(--text2); flex: 1; }
.book-item:not(.off) .book-name { color: var(--text); }
.book-cnt { font-size: 9px; color: var(--text3); }

/* Strand items */
.strand-item { display: flex; align-items: center; gap: 6px; padding: 3px 5px 3px 16px; border-radius: 4px; cursor: pointer; transition: all 0.12s; user-select: none; }
.strand-item:hover { background: rgba(255,255,255,0.03); }
.strand-item.off { opacity: 0.2; }
.strand-dot { width: 7px; height: 7px; border-radius: 3px; flex-shrink: 0; }
.strand-name { font-size: 10px; color: var(--text2); flex: 1; }
.strand-item:not(.off) .strand-name { color: var(--text); }
.strand-cnt { font-size: 9px; color: var(--text3); }

.controls { padding-top: 8px; border-top: 1px solid var(--border); display: flex; flex-direction: column; gap: 6px; }
.ctrl-row { display: flex; align-items: center; justify-content: space-between; }
.ctrl-label { font-size: 10px; color: var(--text3); text-transform: uppercase; letter-spacing: 0.5px; }
.ctrl-slider { -webkit-appearance: none; width: 90px; height: 3px; background: rgba(255,255,255,0.1); border-radius: 2px; outline: none; }
.ctrl-slider::-webkit-slider-thumb { -webkit-appearance: none; width: 12px; height: 12px; background: var(--gold); border-radius: 50%; cursor: pointer; }

.hint { font-size: 9px; color: var(--text3); line-height: 1.6; padding-top: 8px; border-top: 1px solid var(--border); }
.hint b { color: var(--text2); font-weight: 500; }

/* Graph SVG */
#graph-container { position: fixed; top: var(--topbar); left: var(--sidebar); right: 0; bottom: 0; transition: right 0.3s; }
#graph-container.detail-open { right: var(--detail); }
svg { width: 100%; height: 100%; display: block; }

/* Detail panel */
.detail { position: fixed; top: var(--topbar); right: calc(-1 * var(--detail)); bottom: 0; width: var(--detail); background: var(--surface); border-left: 1px solid var(--border); z-index: 100; overflow-y: auto; padding: 20px 16px; transition: right 0.3s; }
.detail.open { right: 0; }
.detail::-webkit-scrollbar { width: 3px; }
.detail::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.08); border-radius: 2px; }
.detail-close { position: absolute; top: 12px; right: 12px; width: 24px; height: 24px; border-radius: 5px; background: rgba(255,255,255,0.04); border: 1px solid var(--border); color: var(--text3); cursor: pointer; display: flex; align-items: center; justify-content: center; font-size: 12px; }
.detail-close:hover { color: var(--text); }
.detail-badge { display: inline-flex; align-items: center; gap: 5px; padding: 2px 8px; border-radius: 12px; font-size: 9px; text-transform: uppercase; letter-spacing: 0.8px; margin-bottom: 6px; }
.detail-pages { display: inline-block; padding: 3px 10px; border-radius: 5px; font-family: 'Instrument Serif', serif; font-size: 16px; background: rgba(255,200,87,0.08); color: var(--gold); border: 1px solid rgba(255,200,87,0.12); margin-bottom: 10px; }
.detail-title { font-family: 'Instrument Serif', serif; font-size: 20px; line-height: 1.2; margin-bottom: 14px; }
.conn-section { margin-top: 12px; padding-top: 10px; border-top: 1px solid var(--border); }
.conn-head { font-size: 9px; text-transform: uppercase; letter-spacing: 0.8px; color: var(--text3); margin-bottom: 6px; }
.conn-head.prereq { color: #e07a5f; }
.conn-head.leads { color: #81b29a; }
.conn-item { display: flex; align-items: center; gap: 6px; padding: 3px 5px; border-radius: 4px; cursor: pointer; transition: background 0.12s; }
.conn-item:hover { background: rgba(255,255,255,0.04); }
.conn-dot { width: 5px; height: 5px; border-radius: 50%; flex-shrink: 0; }
.conn-label { font-size: 11px; color: var(--text2); flex: 1; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.conn-book { font-size: 8px; color: var(--text3); flex-shrink: 0; }

/* Detail tabs (Questions / Videos / Lectures) */
.detail-tabs { display: flex; gap: 0; margin-top: 14px; border-bottom: 1px solid var(--border); }
.detail-tab { flex: 1; padding: 7px 0; font-size: 9px; text-transform: uppercase; letter-spacing: 0.8px; color: var(--text3); background: none; border: none; border-bottom: 2px solid transparent; cursor: pointer; font-family: 'DM Sans', sans-serif; transition: all 0.15s; display: flex; align-items: center; justify-content: center; gap: 4px; }
.detail-tab:hover { color: var(--text2); }
.detail-tab.active { color: var(--gold); border-bottom-color: var(--gold); }
.detail-tab .dt-count { font-size: 8px; background: rgba(255,255,255,0.06); padding: 1px 5px; border-radius: 8px; }
.detail-tab.active .dt-count { background: rgba(255,200,87,0.12); color: var(--gold); }
.detail-tab-pane { display: none; padding-top: 12px; }
.detail-tab-pane.active { display: block; }
.detail-tab-empty { padding: 20px 0; text-align: center; color: var(--text3); font-size: 11px; }

/* Exam questions carousel */
.exam-section { margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--border); }
.exam-head { font-size: 9px; text-transform: uppercase; letter-spacing: 0.8px; color: var(--gold); margin-bottom: 8px; display: flex; align-items: center; gap: 6px; }
.exam-head::before { content: ''; width: 2px; height: 9px; background: var(--gold); border-radius: 1px; }
.exam-nav { display: flex; align-items: center; justify-content: space-between; margin-bottom: 6px; }
.exam-counter { font-size: 9px; color: var(--text3); }
.exam-arrows { display: flex; gap: 4px; }
.exam-arrow { width: 22px; height: 22px; border-radius: 4px; background: rgba(255,255,255,0.04); border: 1px solid var(--border); color: var(--text3); cursor: pointer; display: flex; align-items: center; justify-content: center; font-size: 10px; transition: all 0.12s; }
.exam-arrow:hover { background: rgba(255,200,87,0.08); border-color: rgba(255,200,87,0.15); color: var(--gold); }
.exam-card { display: none; flex-direction: column; gap: 6px; }
.exam-card.active { display: flex; }
.exam-card-header { display: flex; align-items: center; justify-content: space-between; }
.exam-paper { font-size: 9px; color: var(--text2); font-family: 'DM Sans', sans-serif; }
.exam-marks { font-size: 9px; color: var(--gold); background: rgba(255,200,87,0.08); padding: 1px 6px; border-radius: 8px; }
.exam-img-wrap { position: relative; border-radius: 6px; overflow: hidden; border: 1px solid var(--border); cursor: pointer; background: #fff; }
.exam-img-wrap img { width: 100%; display: block; }
.exam-img-wrap:hover { border-color: rgba(255,200,87,0.3); }
.exam-expand-hint { position: absolute; bottom: 0; left: 0; right: 0; padding: 3px; text-align: center; font-size: 8px; color: var(--text3); background: linear-gradient(transparent, rgba(0,0,0,0.6)); opacity: 0; transition: opacity 0.15s; }
.exam-img-wrap:hover .exam-expand-hint { opacity: 1; }

/* Lightbox for expanded view */
.exam-lightbox { display: none; position: fixed; inset: 0; z-index: 10000; background: rgba(0,0,0,0.92); backdrop-filter: blur(8px); align-items: center; justify-content: center; cursor: zoom-out; }
.exam-lightbox.open { display: flex; }
.exam-lightbox img { max-width: 90vw; max-height: 90vh; border-radius: 8px; border: 1px solid var(--border); background: #fff; }

/* Get Directions (sidebar) */
.dir-wrap { padding-top: 8px; border-top: 1px solid var(--border); }
.dir-label { font-size: 9px; text-transform: uppercase; letter-spacing: 0.8px; color: #06b6d4; margin-bottom: 6px; display: flex; align-items: center; gap: 6px; }
.dir-label::before { content: ''; width: 2px; height: 9px; background: #06b6d4; border-radius: 1px; }
.dir-from { font-size: 10px; color: var(--text); margin-bottom: 6px; padding: 4px 8px; background: rgba(6,182,212,0.08); border: 1px solid rgba(6,182,212,0.15); border-radius: 5px; }
.dir-search { border-color: rgba(6,182,212,0.2) !important; }
.dir-search:focus { border-color: rgba(6,182,212,0.4) !important; }
.dir-results { max-height: 150px; overflow-y: auto; border: 1px solid var(--border); border-radius: 5px; background: var(--surface); display: none; margin-top: 4px; }
.dir-results.open { display: block; }
.dir-result { padding: 5px 10px; cursor: pointer; font-size: 11px; color: var(--text2); transition: background 0.1s; display: flex; align-items: center; gap: 6px; }
.dir-result:hover { background: rgba(6,182,212,0.08); }
.dir-result .dr-dot { width: 5px; height: 5px; border-radius: 50%; flex-shrink: 0; }
.dir-result .dr-book { font-size: 8px; color: var(--text3); margin-left: auto; }
.dir-path { margin-top: 8px; }
.dir-step { display: flex; align-items: center; gap: 6px; padding: 4px 6px; font-size: 10px; border-radius: 4px; cursor: pointer; transition: background 0.1s; }
.dir-step:hover { background: rgba(255,255,255,0.04); }
.dir-step-dot { width: 7px; height: 7px; border-radius: 50%; flex-shrink: 0; }
.dir-step-label { color: var(--text); flex: 1; }
.dir-step-book { font-size: 8px; color: var(--text3); }
.dir-arrow { color: var(--text3); font-size: 9px; padding-left: 14px; }
.dir-arrow.uturn { color: #f59e0b; }
.dir-step.start .dir-step-dot { box-shadow: 0 0 0 2px #06b6d4; }
.dir-step.end .dir-step-dot { box-shadow: 0 0 0 2px #ffc857; }
.dir-info { font-size: 9px; color: var(--text3); margin-top: 6px; padding: 4px 6px; background: rgba(255,255,255,0.02); border-radius: 4px; }

/* Curriculum Audit panel */
.audit-section { margin-top: 12px; border-top: 1px solid var(--border); padding-top: 8px; }
.audit-header { display: flex; align-items: center; justify-content: space-between; cursor: pointer; padding: 4px 0; user-select: none; }
.audit-header-title { font-family: 'Instrument Serif', serif; font-size: 13px; display: flex; align-items: center; gap: 6px; }
.audit-header-title::before { content: ''; width: 2px; height: 11px; background: var(--gold); border-radius: 1px; }
.audit-score { font-family: 'Instrument Serif', serif; font-size: 17px; color: var(--gold); }
.audit-body { overflow: hidden; transition: max-height 0.3s ease; max-height: 800px; }
.audit-body.collapsed { max-height: 0; }
.audit-header.collapsed .audit-header-title::after { content: ' \25B6'; font-size: 8px; color: var(--text3); }

.audit-group { font-size: 8px; text-transform: uppercase; letter-spacing: 1px; color: var(--text3); margin-top: 10px; margin-bottom: 4px; padding-top: 6px; border-top: 1px solid var(--border); }
.audit-group:first-child { border-top: none; margin-top: 6px; }

.audit-row { display: flex; align-items: center; gap: 6px; padding: 3px 0; }
.audit-label { font-size: 10px; color: var(--text2); width: 90px; flex-shrink: 0; }
.audit-value { font-size: 10px; width: 50px; flex-shrink: 0; text-align: right; font-family: 'DM Sans', sans-serif; }
.audit-value.pass { color: #81b29a; }
.audit-value.partial { color: #ffc857; }
.audit-value.fail { color: #e07a5f; }
.audit-bar { flex: 1; height: 3px; background: rgba(255,255,255,0.04); border-radius: 2px; overflow: hidden; }
.audit-bar-fill { height: 100%; border-radius: 2px; transition: width 0.6s ease; }

.audit-check { display: flex; align-items: center; gap: 6px; padding: 2px 0; font-size: 10px; }
.audit-check.pass { color: #81b29a; }
.audit-check.fail { color: #e07a5f; }
.audit-icon { font-size: 11px; width: 14px; text-align: center; }
.audit-warn { font-size: 9px; color: #f59e0b; padding: 2px 0 2px 4px; }
.audit-warn code { font-family: 'DM Mono', monospace; font-size: 8px; background: rgba(255,255,255,0.06); padding: 1px 3px; border-radius: 2px; }

.audit-verified { font-size: 7px; font-family: 'DM Sans', sans-serif; text-transform: uppercase; letter-spacing: 0.5px; background: rgba(129,178,154,0.15); color: #81b29a; border: 1px solid rgba(129,178,154,0.25); padding: 1px 4px; border-radius: 3px; }
.audit-unverified { font-size: 7px; font-family: 'DM Sans', sans-serif; text-transform: uppercase; letter-spacing: 0.5px; background: rgba(245,158,11,0.1); color: #f59e0b; border: 1px solid rgba(245,158,11,0.2); padding: 1px 4px; border-radius: 3px; }
.audit-ref-badge { font-size: 7px; font-family: 'DM Sans', sans-serif; background: rgba(129,178,154,0.1); color: #81b29a; padding: 1px 4px; border-radius: 3px; text-transform: none; letter-spacing: 0; }
.audit-unverified-sm { font-size: 7px; font-family: 'DM Sans', sans-serif; color: #f59e0b; opacity: 0.7; text-transform: none; letter-spacing: 0; }

.audit-missing-toggle { font-size: 9px; color: var(--text3); cursor: pointer; padding: 3px 0; user-select: none; }
.audit-missing-toggle:hover { color: var(--text2); }
.audit-missing { padding: 2px 0 4px 0; }
.audit-missing-item { font-size: 9px; color: #e07a5f; padding: 1px 0; opacity: 0.8; }

/* Node completeness in detail panel */
.node-completeness { display: flex; gap: 10px; padding: 8px 0; margin-bottom: 8px; border-bottom: 1px solid var(--border); }
.node-res { display: flex; align-items: center; gap: 3px; }
.node-res-dot { width: 5px; height: 5px; border-radius: 50%; }
.node-res-dot.has { background: var(--gold); box-shadow: 0 0 4px rgba(255,200,87,0.4); }
.node-res-dot.missing { background: var(--text3); opacity: 0.3; }
.node-res-label { font-size: 8px; text-transform: uppercase; letter-spacing: 0.3px; }
.node-res-label.has { color: var(--text); }
.node-res-label.missing { color: var(--text3); }

/* Task generator */
.task-q { font-size: 12px; color: var(--text); line-height: 1.6; padding: 8px 0; }
.task-meta { font-size: 9px; color: var(--gold); background: rgba(255,200,87,0.08); display: inline-block; padding: 2px 8px; border-radius: 8px; margin-bottom: 6px; }
.task-answer { margin-top: 6px; }
.task-answer summary { font-size: 10px; color: var(--text3); cursor: pointer; padding: 4px 0; }
.task-answer summary:hover { color: var(--gold); }
.task-answer-body { font-size: 11px; color: var(--text2); line-height: 1.5; padding: 8px; background: rgba(255,255,255,0.02); border-radius: 6px; border: 1px solid var(--border); margin-top: 4px; }
.task-generate { text-align: center; padding: 10px 0; }
.task-gen-btn { background: rgba(167,139,250,0.12); border: 1px solid rgba(167,139,250,0.25); color: #a78bfa; padding: 8px 16px; border-radius: 6px; font-size: 11px; font-family: 'DM Sans', sans-serif; cursor: pointer; transition: all 0.15s; margin-top: 8px; }
.task-gen-btn:hover { background: rgba(167,139,250,0.2); border-color: rgba(167,139,250,0.4); }
.task-gen-btn:disabled { opacity: 0.5; cursor: wait; }
.task-gen-msg { font-size: 10px; color: var(--text3); margin-top: 8px; padding: 8px; background: rgba(255,255,255,0.02); border-radius: 4px; }

@media (max-width: 800px) {
  .sidebar { display: none; }
  :root { --sidebar: 0px; }
  .topbar .sub, .stats { display: none; }
}