/* ==========================================================================
   Lesson typography, problem statement and Visual Lab components
   ========================================================================== */

/* ───────────── Document ───────────── */
.doc { padding: 26px 30px 40px; max-width: 860px; margin: 0 auto; color: #d3d8e1; font-size: 14.5px; line-height: 1.72; }
.doc h1 { font-size: 27px; line-height: 1.2; letter-spacing: -0.025em; margin: 4px 0 12px; color: var(--text); font-weight: 750; }
.doc h2 {
  display: flex; align-items: center; gap: 11px;
  font-size: 19px; letter-spacing: -0.015em; color: var(--text);
  margin: 40px 0 12px; padding-top: 22px; border-top: 1px solid var(--border);
}
.doc h3 { font-size: 15.5px; color: var(--text); margin: 26px 0 8px; }
.doc p { margin: 0 0 13px; }
.doc strong { color: var(--text); font-weight: 600; }
.doc em { color: #e4e0ff; }
.doc ul, .doc ol { padding-inline-start: 22px; margin: 0 0 14px; }
.doc ul.tight li { margin-bottom: 5px; }
.doc li::marker { color: var(--accent); }
.doc :not(pre) > code {
  font-size: 12.5px; padding: 1.5px 6px; border-radius: 5px;
  background: var(--panel-3); border: 1px solid var(--border); color: #e8d5ff;
}
.h-num {
  width: 26px; height: 26px; border-radius: 8px; flex-shrink: 0;
  display: grid; place-items: center; font-size: 13px; font-weight: 700;
  background: var(--accent-soft); color: var(--accent-hi); border: 1px solid rgba(124, 92, 255, 0.35);
}
.eyebrow { font-size: 11.5px !important; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent-hi); margin: 0 0 4px !important; }
.lede { font-size: 16px; color: var(--text-dim); line-height: 1.7; }
.muted { color: var(--text-faint); }
.small { font-size: 12.5px; }
.mono { font-family: var(--mono); }
.caption { font-size: 12.5px; color: var(--text-faint); text-align: center; margin-top: -4px !important; }

.objectives {
  background: linear-gradient(135deg, rgba(124, 92, 255, 0.1), rgba(34, 211, 238, 0.05));
  border: 1px solid rgba(124, 92, 255, 0.25); border-radius: 12px;
  padding: 14px 18px; margin: 18px 0 6px;
}
.objectives-title { font-size: 11.5px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.08em; color: var(--accent-hi); margin-bottom: 6px; }
.objectives ul { margin: 0; columns: 2; column-gap: 28px; }
.objectives li { break-inside: avoid; margin-bottom: 4px; font-size: 13.5px; }

/* Code blocks */
pre.code {
  background: var(--editor-bg); border: 1px solid var(--border); border-radius: 10px;
  padding: 14px 16px; margin: 12px 0 18px; overflow-x: auto;
  font-size: 12.8px; line-height: 1.65; color: #d6dbe5;
  position: relative;
}
pre.code[data-lang]::before {
  content: attr(data-lang); position: absolute; top: 7px; right: 10px;
  font: 600 10px var(--font); text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-faint);
}
.code-out { color: var(--text-dim); }
.callout pre.code { margin-bottom: 4px; }

/* Tables */
.table { width: 100%; text-align: start; border-collapse: separate; border-spacing: 0; margin: 12px 0 20px; font-size: 13.3px; border: 1px solid var(--border); border-radius: 10px; overflow: hidden; }
.table th { text-align: start; font-size: 11.5px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-faint); background: var(--panel-2); font-weight: 600; }
.table th, .table td { padding: 9px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
.table tr:last-child td { border-bottom: none; }
.table tbody tr:hover { background: rgba(255, 255, 255, 0.02); }

/* Callouts */
.callout { border-radius: 10px; padding: 13px 16px; margin: 16px 0 20px; border: 1px solid; border-inline-start-width: 3px; }
.callout p:last-child, .callout ul:last-child { margin-bottom: 0; }
.callout-title { font-weight: 650; color: var(--text); margin-bottom: 5px; display: flex; align-items: center; gap: 8px; }
.callout-title::before { font-size: 14px; }
.callout-bio { background: rgba(74, 222, 128, 0.06); border-color: rgba(74, 222, 128, 0.25); border-inline-start-color: var(--base-a); }
.callout-bio .callout-title::before { content: "🧬"; }
.callout-cs { background: rgba(124, 92, 255, 0.07); border-color: rgba(124, 92, 255, 0.25); border-inline-start-color: var(--accent); }
.callout-cs .callout-title::before { content: "⌘"; color: var(--accent-hi); }
.callout-tip { background: rgba(34, 211, 238, 0.06); border-color: rgba(34, 211, 238, 0.22); border-inline-start-color: var(--cyan); }
.callout-tip .callout-title::before { content: "💡"; }
.callout-warn { background: var(--warn-soft); border-color: rgba(227, 179, 65, 0.28); border-inline-start-color: var(--warn); }
.callout-warn .callout-title::before { content: "⚠️"; }

/* Formula & complexity */
.formula {
  background: var(--editor-bg); border: 1px solid var(--border); border-radius: 10px;
  padding: 14px 18px; margin: 14px 0 18px; display: flex; flex-direction: column; gap: 6px; align-items: flex-start;
  overflow-x: auto;
}
.formula > div { display: flex; align-items: center; gap: 8px; }
.f-label { font: 500 11.5px var(--mono); color: var(--text-faint); min-width: 80px; }
.f-label:last-child { min-width: 0; }
.f-arrow { font-size: 12px; color: var(--cyan); padding-left: 88px; }
.formula-card { background: var(--panel-2); border: 1px solid var(--border); border-radius: 10px; padding: 12px 18px; margin: 14px 0 16px; }
.fc-row { display: flex; justify-content: space-between; gap: 12px; font-size: 12px; margin-top: 4px; }
.fc-name { font-weight: 600; color: var(--text-dim); }
.fc-when { color: var(--text-faint); }
.fc-eq { font: 500 15px var(--mono); color: var(--text); padding: 6px 0 8px; }
.complexity { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin: 18px 0; }
.complexity > div {
  background: var(--panel-2); border: 1px solid var(--border); border-radius: 10px; padding: 10px 14px;
  display: grid; grid-template-columns: auto 1fr; column-gap: 10px; align-items: baseline;
}
.cx-label { font-size: 11px; text-transform: uppercase; letter-spacing: 0.07em; color: var(--text-faint); font-weight: 600; }
.cx-val { font: 700 18px var(--mono); color: var(--cyan); justify-self: end; }
.cx-note { grid-column: 1 / -1; font-size: 12px; color: var(--text-faint); }

/* Central dogma diagram */
.dogma { display: flex; align-items: center; justify-content: center; gap: 0; margin: 22px 0 10px; }
.dogma-node {
  display: flex; flex-direction: column; align-items: center;
  flex: 0 0 auto; min-width: 92px; padding: 12px 12px; border-radius: 12px;
  font-weight: 700; font-size: 15px; color: var(--text);
  background: var(--panel-2); border: 1px solid var(--border-strong);
}
.dogma-node small { font-weight: 500; font-size: 11px; color: var(--text-faint); }
.dogma-icon { font-size: 18px; margin-bottom: 2px; }
.dogma-dna { border-color: rgba(96, 165, 250, 0.5); box-shadow: 0 0 22px -8px rgba(96, 165, 250, 0.6); }
.dogma-rna { border-color: rgba(192, 132, 252, 0.5); box-shadow: 0 0 22px -8px rgba(192, 132, 252, 0.6); }
.dogma-protein { border-color: rgba(74, 222, 128, 0.5); box-shadow: 0 0 22px -8px rgba(74, 222, 128, 0.6); }
.dogma-arrow { position: relative; flex: 1 1 108px; max-width: 120px; min-width: 64px; height: 34px; display: flex; align-items: flex-start; justify-content: center; }
.dogma-arrow span { font-size: 10.5px; color: var(--text-dim); font-weight: 600; letter-spacing: 0.04em; }
.dogma-arrow::before {
  content: ""; position: absolute; left: 8px; right: 14px; bottom: 9px; height: 2px;
  background: repeating-linear-gradient(90deg, var(--accent-hi) 0 6px, transparent 6px 11px);
  background-size: 22px 2px; animation: flow 0.9s linear infinite;
}
.dogma-arrow::after {
  content: ""; position: absolute; right: 6px; bottom: 5px;
  border: 5px solid transparent; border-left: 8px solid var(--accent-hi);
}
@keyframes flow { to { background-position: 22px 0; } }

/* Inline nucleotide strings */
.seq-inline { display: inline-flex; gap: 2px; vertical-align: middle; }
.nt-i {
  font: 700 12px var(--mono); width: 17px; height: 20px; display: inline-grid; place-items: center; border-radius: 4px;
}
.nt-i.nt-a, .nt.nt-a { color: var(--base-a); background: rgba(74, 222, 128, 0.12); }
.nt-i.nt-t, .nt.nt-t { color: var(--base-t); background: rgba(248, 113, 113, 0.12); }
.nt-i.nt-g, .nt.nt-g { color: var(--base-g); background: rgba(251, 191, 36, 0.12); }
.nt-i.nt-c, .nt.nt-c { color: var(--base-c); background: rgba(96, 165, 250, 0.12); }
.nt-i.nt-u, .nt.nt-u { color: var(--base-u); background: rgba(192, 132, 252, 0.14); }

.pill { font-size: 12px; font-weight: 600; padding: 1px 8px; border-radius: 20px; white-space: nowrap; }
.pill-at { background: rgba(74, 222, 128, 0.12); color: var(--base-a); }
.pill-gc { background: rgba(251, 191, 36, 0.12); color: var(--base-g); }

.bond-demo { display: flex; gap: 14px; justify-content: center; margin: 18px 0; flex-wrap: wrap; }
.bond-pair {
  display: flex; align-items: center; gap: 6px; flex-wrap: wrap; justify-content: center;
  background: var(--panel-2); border: 1px solid var(--border); border-radius: 12px; padding: 14px 20px; width: 200px;
}
.bond-row { display: flex; align-items: center; gap: 6px; }
.bond-pair .nt { width: 34px; height: 34px; font-size: 16px; }
.hb { display: flex; flex-direction: column; gap: 4px; width: 46px; }
.hb i { height: 2px; background: repeating-linear-gradient(90deg, var(--text-dim) 0 4px, transparent 4px 7px); }
.bond-cap { width: 100%; text-align: center; font-size: 12px; color: var(--text-faint); margin-top: 6px; }

.mut-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 14px 0 18px; }
.mut-card { background: var(--panel-2); border: 1px solid var(--border); border-radius: 12px; padding: 13px 16px; border-top: 3px solid; }
.mut-ts { border-top-color: var(--warn); }
.mut-tv { border-top-color: var(--danger); }
.mut-title { font-weight: 700; color: var(--text); }
.mut-ex { margin: 6px 0 8px; font-size: 13px; color: var(--text-faint); text-align: start; }
[dir="rtl"] .mut-ex { text-align: end; }
.mut-card p { font-size: 13px; margin: 0; }

/* Call-to-action & navigation */
.cta-card {
  display: flex; align-items: center; justify-content: space-between; gap: 14px;
  margin: 34px 0 12px; padding: 16px 18px; border-radius: 12px;
  background: linear-gradient(120deg, rgba(124, 92, 255, 0.14), rgba(34, 211, 238, 0.06));
  border: 1px solid rgba(124, 92, 255, 0.3);
}
.cta-title { font-weight: 700; color: var(--text); }
.cta-sub { font-size: 13px; color: var(--text-dim); }
.doc-nav { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 12px; }
.doc-nav-link {
  display: flex; flex-direction: column; padding: 12px 14px; border-radius: 10px;
  border: 1px solid var(--border); background: var(--panel-2); transition: border-color 0.15s, background 0.15s;
}
.doc-nav-link:hover { border-color: var(--accent); background: var(--panel-3); }
.doc-nav-link.next { text-align: end; }
.dn-k { font-size: 11.5px; color: var(--text-faint); }
.dn-v { color: var(--text); font-weight: 600; font-size: 13.5px; }
.doc-nav-end { display: grid; place-items: center; color: var(--text-faint); font-size: 13px; border: 1px dashed var(--border); border-radius: 10px; }

/* ───────────── Problem tab ───────────── */
.problem-head h1 { font-family: var(--mono); font-size: 23px; letter-spacing: -0.01em; }
.problem-meta { display: flex; flex-wrap: wrap; align-items: center; gap: 7px; margin-bottom: 18px; font-size: 12.5px; }
.problem-meta .diff { padding: 2px 10px; border-radius: 20px; background: var(--panel-3); }
.tag { padding: 2px 10px; border-radius: 20px; background: var(--panel-3); color: var(--text-dim); font-size: 12px; }
.tag-solved { background: var(--success-soft); color: var(--success); font-weight: 600; }
.problem-statement { margin-bottom: 18px; }
.example { margin: 14px 0; }
.example-title { font-weight: 650; color: var(--text); margin-bottom: 6px; font-size: 13.5px; }
.example-body {
  border-inline-start: 2px solid var(--border-strong); padding: 8px 14px; background: var(--panel-2);
  border-start-end-radius: 8px; border-end-end-radius: 8px; font-size: 13.3px; display: flex; flex-direction: column; gap: 3px;
}
.ex-k { font-weight: 600; color: var(--text); }
.example-body code.ex-v { display: inline-block; vertical-align: top; background: none !important; border: none !important; padding: 0 !important; color: var(--text-dim) !important; font-size: 13px !important; }
.constraints li { font-size: 13.3px; }
.hints { display: flex; flex-direction: column; gap: 6px; }
.hint { border: 1px solid var(--border); border-radius: 9px; background: var(--panel-2); }
.hint > summary { padding: 9px 13px; cursor: pointer; font-weight: 550; font-size: 13.3px; color: var(--text-dim); list-style: none; user-select: none; }
.hint > summary::-webkit-details-marker { display: none; }
.hint > summary:hover { color: var(--text); }
.hint[open] > summary { color: var(--text); border-bottom: 1px solid var(--border); }
.hint > div { padding: 10px 13px; font-size: 13.3px; }
.hint > pre.code { margin: 10px 12px 12px; }

/* ───────────── Code examples (runnable demos) ───────────── */
.demo {
  margin: 18px 0 26px; border: 1px solid var(--border-strong); border-radius: 14px;
  background: var(--panel-2); overflow: hidden;
}
.demo-head { display: flex; align-items: center; gap: 10px; padding: 12px 16px 0; }
.demo-badge {
  font-size: 11px; font-weight: 700; padding: 2px 9px; border-radius: 20px;
  background: rgba(34, 211, 238, 0.12); color: var(--cyan); border: 1px solid rgba(34, 211, 238, 0.3);
}
.demo-title { font-weight: 700; color: var(--text); font-size: 15px; }
.demo-intro { padding: 6px 16px 0; margin: 0 0 10px !important; color: var(--text-dim); font-size: 13.8px; }
.demo-code { margin: 0 12px; }
.demo-code pre.code { margin: 0; border-end-start-radius: 0; border-end-end-radius: 0; }
.demo-bar {
  display: flex; align-items: center; gap: 10px; padding: 7px 10px;
  background: var(--panel-3); border: 1px solid var(--border); border-top: none;
  border-radius: 0 0 10px 10px;
}
.demo-code .demo-out:not([hidden]) + .demo-bar, .demo-bar:has(+ .demo-out:not([hidden])) { border-radius: 0; }
.demo-run { height: 28px; }
.demo-run.loading > svg { visibility: hidden; }
.demo-hint { font-size: 12px; color: var(--text-faint); direction: rtl; unicode-bidi: isolate; }
.demo-out {
  margin: 0; padding: 10px 14px; max-height: 260px; overflow: auto;
  background: #07090d; border: 1px solid var(--border); border-top: none; border-radius: 0 0 10px 10px;
  font: 12.5px/1.6 var(--mono); color: #c9f2d0; white-space: pre; 
}
.demo-out::before { content: "$ python example.py"; display: block; color: var(--text-faint); margin-bottom: 4px; }
.demo-out.demo-out-error { color: #ffb4ad; }
.demo-steps-title { padding: 14px 16px 4px; font-weight: 650; color: var(--text); font-size: 13.5px; }
.demo-steps { margin: 0 !important; padding: 0 16px 14px !important; list-style: none; counter-reset: step; }
.demo-steps li {
  position: relative; counter-increment: step;
  padding-inline-start: 34px; margin-bottom: 9px; font-size: 13.6px; line-height: 1.7;
}
.demo-steps li::before {
  content: counter(step); position: absolute; inset-inline-start: 0; top: 2px;
  width: 22px; height: 22px; border-radius: 50%; display: grid; place-items: center;
  font: 700 11px var(--font); color: var(--accent-hi);
  background: var(--accent-soft); border: 1px solid rgba(124, 92, 255, 0.35);
}
.solution-box { margin-top: 18px; }

/* ───────────── Visual Lab shell ───────────── */
.viz {
  margin: 16px 0 24px;
  background: linear-gradient(180deg, var(--panel-2), var(--panel));
  border: 1px solid var(--border-strong); border-radius: 14px;
  padding: 16px; box-shadow: 0 16px 40px -24px rgba(0, 0, 0, 0.8);
  font-size: 13.3px; line-height: 1.55;
}
.viz-head { margin-bottom: 12px; }
.viz-title { display: flex; align-items: center; gap: 8px; font-weight: 700; color: var(--text); font-size: 14px; }
.viz-sep { color: var(--text-faint); font-weight: 400; }
.viz-dot { width: 8px; height: 8px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.18); animation: pulse 2s ease-in-out infinite; }
.viz-sub { color: var(--text-faint); font-size: 12.5px; margin-top: 2px; }

.viz-controls { display: flex; gap: 12px; align-items: flex-end; flex-wrap: wrap; margin-bottom: 12px; }
.viz-controls.col { flex-direction: column; align-items: stretch; }
.field { display: flex; flex-direction: column; gap: 4px; min-width: 0; }
.field.grow { flex: 1 1 260px; }
.field-label { font-size: 11px; font-weight: 600; color: var(--text-faint); text-transform: uppercase; letter-spacing: 0.06em; }
.field-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.field-pair-wide { grid-template-columns: 3fr 1fr; }
.btn-row { display: flex; gap: 6px; align-items: center; }
.btn-row.wrap { flex-wrap: wrap; gap: 10px 14px; }
.inline-field { display: inline-flex; align-items: center; gap: 8px; font-size: 12.5px; color: var(--text-dim); font-weight: 550; }
.inline-field.grow { flex: 1; }
.inline-field output { font: 600 12px var(--mono); color: var(--text); min-width: 38px; }
input[type="range"] { accent-color: var(--accent); cursor: pointer; }

.viz-stage-wrap { display: flex; background: var(--editor-bg); border: 1px solid var(--border); border-radius: 10px; overflow: hidden; }
.viz-stage-wrap .viz-stage { border: none; border-radius: 0; flex: 1; }
.lane-labels {
  display: flex; flex-direction: column; gap: 0; flex-shrink: 0;
  padding: 16px 10px 26px 12px; border-right: 1px solid var(--border); background: rgba(255, 255, 255, 0.015);
}
.lane-labels > span { display: flex; align-items: center; justify-content: flex-end; font: 500 10.5px var(--mono); color: var(--text-faint); white-space: nowrap; }
.lane-labels .lbl-rna { color: var(--base-u); }
.viz-stage {
  background: var(--editor-bg); border: 1px solid var(--border); border-radius: 10px;
  padding: 16px 14px 26px; overflow-x: auto; overflow-y: hidden;
  scroll-behavior: auto;
}

/* Base tiles (26px + 4px gap = 30px column — matches COL in visuals.js) */
.nt {
  width: 26px; height: 26px; flex-shrink: 0;
  display: inline-grid; place-items: center;
  font: 700 13px var(--mono); border-radius: 6px;
  border: 1px solid rgba(255, 255, 255, 0.06);
  transition: transform 0.28s cubic-bezier(0.2, 0.8, 0.2, 1), opacity 0.28s, background 0.2s, box-shadow 0.2s, border-color 0.2s;
}
.nt.nt-a { border-color: rgba(74, 222, 128, 0.3); }
.nt.nt-t { border-color: rgba(248, 113, 113, 0.3); }
.nt.nt-g { border-color: rgba(251, 191, 36, 0.3); }
.nt.nt-c { border-color: rgba(96, 165, 250, 0.3); }
.nt.nt-u { border-color: rgba(192, 132, 252, 0.35); }
.nt-gap { color: var(--text-faint); border: 1px dashed var(--border-strong); background: transparent; }
.nt.nt-xs { width: 20px; height: 20px; font-size: 11.5px; vertical-align: middle; border-radius: 4px; }

.tx-bond { display: flex; justify-content: center; gap: 3px; height: 16px; transition: opacity 0.25s; }
.tx-bond i { width: 2px; height: 100%; background: rgba(231, 234, 240, 0.28); border-radius: 2px; }
.tx-bond.b2 i:nth-child(3) { display: none; }

.legend { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 8px; margin-top: 10px; font-size: 12px; color: var(--text-faint); }
.legend .nt { width: 20px; height: 20px; font-size: 11px; }
.legend span:not(.nt) { margin-inline-end: 8px; }

.viz-readout {
  margin-top: 10px; min-height: 44px; padding: 10px 13px;
  background: var(--panel-3); border: 1px solid var(--border); border-radius: 9px;
  font-size: 13px; color: var(--text-dim);
}
.viz-readout b { color: var(--text); }
.ro-seq { margin-top: 4px; font-size: 12.5px; word-break: break-all; }
.ro-seq .mono { color: var(--base-u); letter-spacing: 0.04em; }
.ro-good { color: var(--success); font-weight: 600; }
.ro-warn { color: var(--warn); font-weight: 600; }
.ro-bad { color: var(--danger); font-weight: 600; }
.ro-dim { color: var(--text-faint); }
.viz-foot { font-size: 11.5px; color: var(--text-faint); margin: 10px 0 0 !important; line-height: 1.5; }

.stat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin: 12px 0 10px; }
.stat-grid-6 { grid-template-columns: repeat(3, 1fr); }
.stat { background: var(--panel-3); border: 1px solid var(--border); border-radius: 9px; padding: 8px 11px; min-width: 0; }
.stat-k { unicode-bidi: plaintext; font-size: 10.5px; color: var(--text-faint); text-transform: uppercase; letter-spacing: 0.05em; font-weight: 600; display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.stat-k .dot { margin-inline-end: 5px; vertical-align: 1px; }
[dir="rtl"] .stat-v { text-align: right; }
.stat-v { font: 700 16px var(--mono); color: var(--text); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.stat-n { font-size: 10.5px; color: var(--text-faint); }
.stat-accent { border-color: rgba(124, 92, 255, 0.45); background: rgba(124, 92, 255, 0.1); }
.stat-accent .stat-v { color: var(--accent-hi); }
.dot { width: 8px; height: 8px; border-radius: 50%; display: inline-block; flex-shrink: 0; }
.dot-ts { background: var(--warn); }
.dot-tv { background: var(--danger); }

/* ───────────── 1. Transcription ───────────── */
.tx-track { display: flex; gap: 4px; position: relative; width: max-content; }
.tx-col { display: flex; flex-direction: column; align-items: center; width: 26px; }
.tx-col.open .tx-coding { transform: translateY(-8px); }
.tx-col.open .tx-template { transform: translateY(8px); box-shadow: 0 0 0 1.5px rgba(34, 211, 238, 0.55); }
.tx-col.open .tx-bond { opacity: 0; }
.tx-rna { margin-top: 22px; opacity: 0; transform: translateY(-26px) scale(0.5); }
.tx-col.made .tx-rna { opacity: 1; transform: none; }
.rnap {
  position: absolute; left: 0; top: -8px; width: 32px; height: 132px;
  border: 1.5px solid var(--cyan); border-radius: 9px;
  background: rgba(34, 211, 238, 0.07);
  box-shadow: 0 0 20px -4px rgba(34, 211, 238, 0.45);
  opacity: 0; transition: transform 0.2s ease, opacity 0.3s; pointer-events: none;
}
.rnap.on { opacity: 1; }
.rnap span {
  position: absolute; bottom: -17px; left: 50%; transform: translateX(-50%);
  font: 700 9px var(--mono); color: var(--cyan); white-space: nowrap;
}

/* ───────────── 2. GC / melting ───────────── */
.comp-bar { display: flex; height: 22px; border-radius: 7px; overflow: hidden; margin: 2px 0 14px; background: var(--panel-3); }
.comp-seg { display: grid; place-items: center; font: 700 10.5px var(--mono); color: rgba(0, 0, 0, 0.75); transition: width 0.4s cubic-bezier(0.2, 0.8, 0.2, 1); overflow: hidden; white-space: nowrap; }
.comp-a { background: var(--base-a); }
.comp-t { background: var(--base-t); }
.comp-g { background: var(--base-g); }
.comp-c { background: var(--base-c); }
.melt-head { display: flex; align-items: center; margin-bottom: 8px; }
.temp-range { flex: 1; accent-color: #f97316; }
.temp-out {
  --heat: 0.1;
  min-width: 62px !important; text-align: center; padding: 2px 8px; border-radius: 6px;
  background: color-mix(in srgb, #3b82f6 calc((1 - var(--heat)) * 100%), #ef4444);
  color: #fff !important;
}
.duplex { display: flex; gap: 4px; width: max-content; padding: 2px 0; }
.dx-col { display: flex; flex-direction: column; align-items: center; width: 26px; }
.dx-col.melted .dx-top { transform: translateY(-9px) rotate(-10deg); opacity: 0.55; }
.dx-col.melted .dx-bot { transform: translateY(9px) rotate(10deg); opacity: 0.55; }
.dx-col.melted .tx-bond { opacity: 0; }

/* ───────────── 3. Hamming ───────────── */
.hm-track { display: flex; gap: 4px; width: max-content; }
.hm-col { display: flex; flex-direction: column; align-items: center; width: 26px; position: relative; transition: opacity 0.2s; }
.hm-mark { height: 22px; display: grid; place-items: center; font-size: 12px; color: var(--border-strong); font-weight: 700; }
.hm-idx { height: 16px; font: 500 9.5px var(--mono); color: var(--text-faint); padding-top: 4px; }
.hm-ts .hm-mark { color: var(--warn); }
.hm-tv .hm-mark { color: var(--danger); }
.hm-gap .hm-mark { color: var(--text-faint); }
.hm-ts .nt { box-shadow: 0 0 0 1.5px var(--warn); }
.hm-tv .nt { box-shadow: 0 0 0 1.5px var(--danger); }
.hm-col.seen { opacity: 0.45; }
.hm-col.scan::before {
  content: ""; position: absolute; inset: -6px -3px 12px; border-radius: 9px;
  border: 2px solid var(--cyan); box-shadow: 0 0 16px -2px rgba(34, 211, 238, 0.5);
}
.hm-col.flash > .nt:nth-child(3) { animation: flash 0.9s ease 2; }
@keyframes flash { 50% { transform: scale(1.25); box-shadow: 0 0 0 3px var(--accent-hi); } }

/* ───────────── 4. Motif ───────────── */
.mf-track { position: relative; width: max-content; }
.mf-hits { position: relative; height: 20px; }
.mf-hit {
  position: absolute; top: 0; left: 0; width: 26px; text-align: center;
  font: 700 10px var(--mono); color: var(--accent-hi); animation: rise 0.3s ease;
}
.mf-row, .mf-pattern { display: flex; gap: 4px; }
.mf-idx { display: flex; gap: 4px; margin-top: 3px; }
.mf-idx span { width: 26px; text-align: center; font: 500 9.5px var(--mono); color: var(--text-faint); }
.mf-pattern { margin-top: 10px; transition: transform 0.22s ease, opacity 0.2s; }
.mf-window {
  position: absolute; left: -3px; top: 16px; height: 34px;
  border: 2px solid var(--accent-hi); border-radius: 8px;
  background: rgba(124, 92, 255, 0.08);
  box-shadow: 0 0 18px -4px rgba(124, 92, 255, 0.6);
  transition: transform 0.22s ease, opacity 0.2s; pointer-events: none;
}
.nt.hit { background: rgba(124, 92, 255, 0.3); border-color: var(--accent-hi); color: #fff; }
.nt.cmp-ok { box-shadow: 0 0 0 2px var(--success); transform: translateY(-2px); }
.nt.cmp-bad { box-shadow: 0 0 0 2px var(--danger); animation: shake 0.3s; }
@keyframes shake { 25% { transform: translateX(-2px); } 75% { transform: translateX(2px); } }

/* ───────────── 5. Genetic code table & translation ───────────── */
.gc-wrap { overflow-x: auto; margin: 16px 0 6px; }
.gc-table { border-collapse: separate; border-spacing: 3px; width: 100%; min-width: 470px; font-size: 11.5px; }
.gc-table th { font: 700 13px var(--mono); color: var(--accent-hi); padding: 4px; }
.gc-table thead th { border-bottom: 1px solid var(--border); }
.gc-table tbody th { border-right: 1px solid var(--border); width: 26px; }
.gc-corner { font: 500 9.5px var(--font) !important; color: var(--text-faint) !important; white-space: nowrap; }
.gc-corner span { display: block; line-height: 1.2; }
.gc-table td { background: var(--panel-2); border: 1px solid var(--border); border-radius: 7px; padding: 4px 6px; vertical-align: top; }
.gc-entry { display: grid; grid-template-columns: 30px 1fr 12px; gap: 4px; line-height: 1.7; color: var(--text-dim); }
.gc-entry .mono { color: var(--text); }
.gc-entry b { color: var(--text); text-align: end; }
.gc-entry.gc-start, .gc-entry.gc-start b { color: var(--base-a); }
.gc-entry.gc-stop, .gc-entry.gc-stop b, .gc-entry.gc-stop .mono { color: var(--base-t); }

.tl-track { display: flex; gap: 12px; width: max-content; padding: 2px 0 4px; }
.tl-codon { display: flex; flex-direction: column; align-items: center; gap: 4px; padding: 5px 4px 6px; border-radius: 10px; border: 1.5px solid transparent; transition: border-color 0.2s, background 0.2s, opacity 0.3s; margin: -5px -4px; }
.tl-bases { display: flex; gap: 4px; }
.tl-idx { font: 500 9.5px var(--mono); color: var(--text-faint); align-self: flex-start; padding-left: 2px; }
.tl-codon.active { border-color: var(--cyan); background: rgba(34, 211, 238, 0.07); box-shadow: 0 0 18px -6px rgba(34, 211, 238, 0.6); }
.tl-codon.after-stop, .tl-rest { opacity: 0.35; }
.aa-chip {
  min-width: 60px; height: 34px; padding: 2px 8px; border-radius: 17px;
  display: flex; flex-direction: column; align-items: center; justify-content: center; line-height: 1.1;
  background: rgba(124, 92, 255, 0.16); border: 1px solid rgba(124, 92, 255, 0.45); color: #fff;
  opacity: 0; transform: translateY(-10px) scale(0.6);
  transition: opacity 0.3s, transform 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
}
.aa-chip b { font: 700 13px var(--mono); }
.aa-chip span { font-size: 9.5px; color: var(--text-dim); }
.aa-chip.aa-met { background: rgba(74, 222, 128, 0.15); border-color: rgba(74, 222, 128, 0.5); }
.aa-chip.aa-stop { background: var(--danger-soft); border-color: rgba(248, 81, 73, 0.6); color: #ffb4ad; }
.tl-codon.made .aa-chip { opacity: 1; transform: none; }
.protein-bar {
  display: flex; align-items: center; gap: 10px; margin-top: 10px; padding: 9px 13px;
  background: var(--editor-bg); border: 1px solid var(--border); border-radius: 9px; min-height: 42px;
}
.pb-label { font-size: 12px; font-weight: 600; color: var(--text-faint); }
.pb-seq { flex: 1; font-size: 14px; font-weight: 600; letter-spacing: 0.12em; color: var(--accent-hi); word-break: break-all; text-align: left; }
.pb-len { font-size: 12px; color: var(--text-faint); white-space: nowrap; }

/* ───────────── 6. ORFs ───────────── */
.orf-figure { align-items: center !important; }
.orf-row { display: flex; gap: 6px; align-items: center; }
.orf-codon { width: 52px; text-align: center; padding: 4px 0; border-radius: 7px; font: 700 13px var(--mono); }
.orf-out { width: 30px; color: var(--text-faint); }
.orf-blank { width: 30px; visibility: hidden; padding: 0; }
.orf-start { background: rgba(74, 222, 128, 0.16); color: var(--base-a); border: 1px solid rgba(74, 222, 128, 0.45); }
.orf-stop { background: var(--danger-soft); color: var(--base-t); border: 1px solid rgba(248, 81, 73, 0.5); }
.orf-in { background: var(--accent-soft); color: var(--text); border: 1px solid rgba(124, 92, 255, 0.3); }
.orf-labels { margin-top: 2px; }
.orf-tag { font: 600 10.5px var(--font); text-align: center; color: var(--text-faint); width: 52px; }
.orf-tag.orf-span { width: 110px; border-top: 2px solid var(--accent); padding-top: 2px; color: var(--accent-hi); }
.orf-tag.tag-start { color: var(--base-a); }
.orf-tag.tag-stop { color: var(--base-t); }

.of-track { width: max-content; }
.of-seq, .of-idx { display: flex; gap: 4px; }
.of-idx span { width: 26px; text-align: center; height: 16px; font: 500 9.5px var(--mono); color: var(--text-faint); padding-top: 3px; }
.of-frame { position: relative; height: 32px; }
.of-codon {
  position: absolute; top: 6px; height: 26px; border-radius: 6px; z-index: 1;
  display: grid; place-items: center; font: 600 11.5px var(--mono); letter-spacing: 0.08em;
  color: var(--text-dim); background: var(--panel-3); border: 1px solid var(--border);
  transition: box-shadow 0.2s, background 0.2s;
}
.of-codon.of-start { color: var(--base-a); background: rgba(74, 222, 128, 0.14); border-color: rgba(74, 222, 128, 0.5); }
.of-codon.of-stop { color: var(--base-t); background: var(--danger-soft); border-color: rgba(248, 81, 73, 0.55); }
.of-codon.reading { box-shadow: 0 0 0 2px var(--cyan); }
.of-band {
  position: absolute; top: 3px; height: 32px; border-radius: 9px; z-index: 0;
  background: rgba(124, 92, 255, 0.12); border: 1px dashed rgba(124, 92, 255, 0.5);
}
.of-band.found { background: rgba(124, 92, 255, 0.28); border: 2px solid var(--accent-hi); box-shadow: 0 0 20px -4px rgba(124, 92, 255, 0.7); }
.of-seq .nt.probe { box-shadow: 0 0 0 2px var(--cyan); transform: translateY(-2px); }
.of-seq .nt.reading { background: rgba(124, 92, 255, 0.28); border-color: var(--accent-hi); color: #fff; }
.lg-box { width: 14px; height: 14px; border-radius: 4px; display: inline-block; }
.lg-start { background: rgba(74, 222, 128, 0.25); border: 1px solid var(--base-a); }
.lg-stop { background: var(--danger-soft); border: 1px solid var(--base-t); }
.lg-orf { background: rgba(124, 92, 255, 0.15); border: 1px dashed var(--accent); }
.lg-found { background: rgba(124, 92, 255, 0.35); border: 2px solid var(--accent-hi); }

/* ───────────── 7. Alignment scoring ───────────── */
.align-figure { align-items: center !important; }
.al-track { display: flex; gap: 4px; width: max-content; }
.al-col { display: flex; flex-direction: column; align-items: center; width: 26px; transition: opacity 0.2s; position: relative; }
.al-mark { height: 18px; display: grid; place-items: center; font-weight: 700; color: var(--success); }
.al-mismatch .al-mark { color: var(--warn); }
.al-score { height: 24px; display: grid; place-items: center; font: 700 11px var(--mono); margin-top: 2px; }
.al-match .al-score { color: var(--success); }
.al-mismatch .al-score { color: var(--warn); }
.al-gap .al-score { color: var(--danger); }
.al-mismatch .nt { box-shadow: 0 0 0 1.5px var(--warn); }
.al-gap .nt-gap { border-color: var(--danger); color: var(--danger); }
.al-missing { opacity: 0.5; }
.al-total { font: 700 13px var(--mono); color: var(--accent-hi); margin-top: 8px; }
.al-live .al-col.pending { opacity: 0.3; }
.al-live .al-col.scan::before {
  content: ""; position: absolute; inset: -6px -3px -2px; border-radius: 9px;
  border: 2px solid var(--cyan); box-shadow: 0 0 16px -2px rgba(34, 211, 238, 0.5);
}
.al-chart { display: block; margin-top: 8px; overflow: visible; }
.al-zero { stroke: var(--border-strong); stroke-dasharray: 3 4; }
.al-zero-label { fill: var(--text-faint); font: 500 9px var(--mono); }
.al-line { fill: none; stroke: var(--accent-hi); stroke-width: 2; stroke-linejoin: round; stroke-linecap: round; }
.al-dot { stroke: var(--editor-bg); stroke-width: 1.5; }
.al-dot-match { fill: var(--success); }
.al-dot-mismatch { fill: var(--warn); }
.al-dot-gap { fill: var(--danger); }

/* ───────────── 8. Reverse complement ───────────── */
.rc-duplex, .rc-result { display: flex; gap: 4px; width: max-content; }
.rc-col { display: flex; flex-direction: column; align-items: center; width: 26px; }
.rc-col .rc-comp { opacity: 0; transform: translateY(-8px) scale(0.7); }
.rc-col.filled .rc-comp { opacity: 1; transform: none; }
.rc-col .tx-bond { opacity: 0.25; transition: opacity 0.25s; }
.rc-col.filled .tx-bond { opacity: 1; }
.rc-col.src .rc-comp { box-shadow: 0 0 0 2px var(--cyan); transform: translateY(3px); }
.rc-gap { height: 34px; display: flex; align-items: center; }
.rc-arrow { font-size: 11px; color: var(--cyan); opacity: 0; transition: opacity 0.3s; direction: rtl; }
.rc-arrow.on { opacity: 1; }
.rc-slot { opacity: 0.5; }
.nt.rc-new { animation: rise 0.3s ease; box-shadow: 0 0 0 1.5px var(--base-u); }

/* ───────────── 9. k-mers ───────────── */
.km-figure { gap: 4px !important; }
.km-fig-row { display: flex; gap: 4px; align-items: center; }
.km-fig-seq { margin-bottom: 6px; padding-bottom: 6px; border-bottom: 1px dashed var(--border-strong); }
.km-pad { width: 26px; flex-shrink: 0; }
.km-fig-label { font: 500 10.5px var(--mono); color: var(--text-faint); margin-left: 10px; }
.km-window { top: -4px !important; }
.nt.in-win { background: rgba(124, 92, 255, 0.22); color: #fff; }
.km-table { display: flex; flex-direction: column; gap: 4px; margin-top: 4px; }
.km-row { display: grid; grid-template-columns: 90px 1fr 34px; gap: 10px; align-items: center; padding: 3px 8px; border-radius: 7px; transition: background 0.2s; }
.km-row.just { background: var(--accent-soft); }
.km-kmer { font-size: 12.5px; color: var(--text); letter-spacing: 0.08em; text-align: left; }
.km-bar { height: 10px; background: var(--panel-3); border-radius: 6px; overflow: hidden; }  /* grows from the k-mer label side (RTL) */
.km-bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--accent), var(--cyan)); border-radius: 6px; transition: width 0.3s; }
.km-count { font: 700 12.5px var(--mono); text-align: left; }
.km-more, .km-empty { font-size: 12px; color: var(--text-faint); padding: 4px 8px; }

/* ───────────── 10. Profile & consensus ───────────── */
.profile-wrap { overflow-x: auto; margin: 14px 0 6px; }
.profile-table { border-collapse: separate; border-spacing: 4px 3px; margin: 0 auto; }
.profile-table th { font: 600 11px var(--mono); color: var(--text-faint); padding: 0 6px; }
.profile-table td { padding: 0; text-align: center; }
.pf-count td, .pf-count td { font: 600 12px var(--mono); }
.profile-table .pf-count td { width: 26px; height: 24px; border-radius: 5px; background: rgba(124, 92, 255, calc(var(--a) * 0.55)); color: var(--text); }
.profile-table .pf-count td.pf-max { outline: 2px solid var(--accent-hi); }
.pf-sep td { height: 6px; border-bottom: 1px dashed var(--border-strong); }
.pf-cons th { color: var(--warn) !important; font-size: 14px !important; }
.pf-grid { width: max-content; }
.pf-line { display: flex; gap: 4px; align-items: center; margin-bottom: 4px; }
.pf-label { width: 26px; text-align: center; font: 600 10.5px var(--mono); color: var(--text-faint); flex-shrink: 0; }
.pf-label .nt { width: 22px; height: 22px; font-size: 11px; }
.pf-star { color: var(--warn); font-size: 14px; }
.pf-cell, .pf-cons { width: 26px; display: inline-flex; justify-content: center; border-radius: 7px; }
.pf-cell.col-on .nt { box-shadow: 0 0 0 2px var(--cyan); }
.pf-divider { height: 1px; border-top: 1px dashed var(--border-strong); margin: 8px 0 8px 30px; }
.pf-count {
  width: 26px; height: 24px; border-radius: 5px; display: grid; place-items: center;
  font: 600 12px var(--mono); color: var(--text);
  background: rgba(124, 92, 255, calc(var(--a, 0) * 0.55)); border: 1px solid var(--border);
}
.pf-count.col-on { border-color: var(--cyan); }
.pf-count.pf-max { outline: 2px solid var(--accent-hi); outline-offset: -1px; }
.pf-count.pf-tie { outline-color: var(--warn); }
.pf-consline { margin-top: 6px; }
.pf-cons .nt { animation: rise 0.3s ease; }

/* ───────────── 11. Dynamic programming grid ───────────── */
.dp-wrap { overflow-x: auto; margin: 14px 0 6px; }
.dp-table { border-collapse: separate; border-spacing: 3px; margin: 0 auto; }
.dp-table th { font: 700 12.5px var(--mono); color: var(--accent-hi); width: 36px; height: 28px; text-align: center; }
.dp-table td {
  width: 36px; height: 30px; text-align: center; border-radius: 6px;
  font: 600 12px var(--mono); color: var(--text-dim);
  background: var(--panel-2); border: 1px solid var(--border); transition: background 0.2s, box-shadow 0.2s;
}
.dp-table td.dp-init { background: rgba(34, 211, 238, 0.12); border-color: rgba(34, 211, 238, 0.45); color: var(--cyan); }
.dp-table td.dp-empty { color: var(--text-faint); }
.dp-table td.dp-filled { color: var(--text); }
.dp-table td.dp-cur { box-shadow: 0 0 0 2px var(--accent-hi); background: var(--accent-soft); color: #fff; }
.dp-table td.dp-nb { box-shadow: 0 0 0 2px var(--warn); }
.dp-table td.dp-path { background: rgba(74, 222, 128, 0.2); border-color: var(--success); color: #fff; }
.dp-stage { padding: 12px; }
.dp-legend { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 8px; margin-top: 10px; font-size: 12px; color: var(--text-faint); }
.dp-legend span:not(.lg-box) { margin-inline-end: 8px; }
.dp-lg-init { background: rgba(34, 211, 238, 0.25); border: 1px solid var(--cyan); }
.dp-lg-cur { background: var(--accent-soft); border: 2px solid var(--accent-hi); }
.dp-lg-nb { border: 2px solid var(--warn); }
.dp-lg-path { background: rgba(74, 222, 128, 0.3); border: 1px solid var(--success); }
.dp-align { margin: 8px 0 0; padding: 8px 12px; background: var(--editor-bg); border: 1px solid var(--border); border-radius: 8px; font: 600 13px/1.5 var(--mono); color: var(--text); letter-spacing: 0.15em; display: inline-block; }

/* ───────────── Responsive ───────────── */
@media (max-width: 720px) {
  .doc { padding: 20px 16px 32px; }
  .objectives ul { columns: 1; }
  .stat-grid, .stat-grid-6 { grid-template-columns: repeat(2, 1fr); }
  .field-pair, .field-pair-wide, .mut-grid, .complexity, .doc-nav { grid-template-columns: 1fr; }
  .dogma-arrow span { font-size: 9px; }
  .cta-card { flex-direction: column; align-items: flex-start; }
  .table { display: block; overflow-x: auto; }
}