/* Built for a monitor: large text, little white space. Light by default, dark on request. */
:root {
  color-scheme: light;
  --surface-0: #f4f3f0;
  --surface-1: #fcfcfb;
  --line: #dcdad4;
  --text-primary: #0b0b0b;
  --text-secondary: #52514e;
  --text-muted: #6f6e69;
  --series-1: #2a78d6;   /* clean audio */
  --series-2: #eb6834;   /* phone-quality audio */
  --human: #2a78d6;
  --ai: #eb6834;
  --good: #006300;
  --warn-bg: #fff4d6;
  --warn-line: #e0b84a;
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --surface-0: #121211;
  --surface-1: #1a1a19;
  --line: #3a3a37;
  --text-primary: #f0efec;
  --text-secondary: #c3c2b7;
  --text-muted: #a3a29a;
  --series-1: #3987e5;
  --series-2: #d95926;
  --human: #3987e5;
  --ai: #d95926;
  --good: #5fd35f;
  --warn-bg: #3a3320;
  --warn-line: #8a7430;
}
* { box-sizing: border-box; }
html { font-size: 20px; }
body {
  margin: 0; background: var(--surface-0); color: var(--text-primary);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; line-height: 1.45;
}
header.top {
  display: flex; align-items: center; gap: 1.2rem; padding: .7rem 1.6rem;
  background: var(--surface-1); border-bottom: 1px solid var(--line);
}
header.top h1 { font-size: 1.2rem; margin: 0; font-weight: 650; }
header.top nav { display: flex; gap: .4rem; margin-left: auto; }
header.top a, button.btn {
  font: inherit; font-size: .85rem; color: var(--text-primary); text-decoration: none;
  padding: .35rem .8rem; border: 1px solid var(--line); border-radius: 8px;
  background: var(--surface-1); cursor: pointer;
}
header.top a[aria-current="page"] { background: var(--text-primary); color: var(--surface-1); border-color: var(--text-primary); }
button.btn.primary { background: var(--series-1); color: #fff; border-color: var(--series-1); }
button.btn:disabled { opacity: .5; cursor: not-allowed; }
main { padding: 1rem 1.6rem 2rem; max-width: 1700px; margin: 0 auto; }
.grid { display: grid; gap: 1rem; }
.cols-2 { grid-template-columns: 1fr 1fr; }
.cols-3 { grid-template-columns: repeat(3, 1fr); }
.cols-demo { grid-template-columns: 5fr 7fr; }
.card { background: var(--surface-1); border: 1px solid var(--line); border-radius: 12px; padding: 1rem 1.2rem; }
.card h2 { font-size: 1.05rem; margin: 0 0 .5rem; }
.muted { color: var(--text-secondary); }
.small { font-size: .8rem; color: var(--text-muted); }
.tile { cursor: pointer; transition: border-color .15s; }
.tile:hover, .tile:focus-visible { border-color: var(--text-secondary); outline: none; }
.tile .big { font-size: 2.6rem; font-weight: 700; line-height: 1.05; font-variant-numeric: tabular-nums; }
.tile .label { font-size: .85rem; color: var(--text-secondary); }
/* demo */
.drop { border: 2px dashed var(--line); border-radius: 12px; padding: 1.2rem; text-align: center; background: var(--surface-0); }
.drop.over { border-color: var(--series-1); }
.row { display: flex; gap: .5rem; flex-wrap: wrap; align-items: center; }
.samples { display: grid; grid-template-columns: 1fr 1fr; gap: .4rem; margin-top: .5rem; }
.samples button { text-align: left; }
.verdict { font-size: 3.2rem; font-weight: 750; line-height: 1; }
.verdict.ai { color: var(--ai); } .verdict.human { color: var(--human); }
.bar2 { display: flex; height: 38px; border-radius: 8px; overflow: hidden; gap: 2px; margin: .6rem 0; }
.bar2 div { display: flex; align-items: center; padding: 0 .6rem; color: #fff; font-weight: 650; font-size: .9rem; min-width: 0; white-space: nowrap; overflow: hidden; }
.bar2 .h { background: var(--human); } .bar2 .a { background: var(--ai); }
.timeline { display: flex; align-items: flex-end; gap: 4px; height: 120px; border-bottom: 1px solid var(--line); padding-top: 4px; }
.timeline .w { flex: 1; min-width: 6px; max-width: 70px; border-radius: 4px 4px 0 0; background: var(--ai); cursor: pointer; position: relative; }
.timeline .w:hover { filter: brightness(1.1); }
.legend { display: flex; gap: 1.2rem; font-size: .8rem; color: var(--text-secondary); margin: .4rem 0; }
.legend i { display: inline-block; width: 12px; height: 12px; border-radius: 3px; margin-right: .35rem; vertical-align: -1px; }
.note { background: var(--warn-bg); border: 1px solid var(--warn-line); border-radius: 10px; padding: .6rem .9rem; font-size: .8rem; }
.status { min-height: 1.3rem; font-size: .85rem; color: var(--text-secondary); }
/* charts */
svg text { fill: var(--text-secondary); font-size: 13px; }
svg .val { fill: var(--text-primary); font-weight: 600; }
.bar-hit { cursor: pointer; }
table.data { border-collapse: collapse; width: 100%; font-size: .8rem; font-variant-numeric: tabular-nums; }
table.data th, table.data td { text-align: left; padding: .3rem .5rem; border-bottom: 1px solid var(--line); }
#tip { position: fixed; pointer-events: none; background: var(--text-primary); color: var(--surface-1); padding: .35rem .6rem; border-radius: 6px; font-size: .78rem; display: none; z-index: 20; max-width: 320px; }
dialog { border: 1px solid var(--line); border-radius: 12px; background: var(--surface-1); color: var(--text-primary); max-width: 640px; padding: 1.2rem 1.4rem; }
dialog::backdrop { background: rgba(0,0,0,.45); }
dialog h3 { margin: 0 0 .5rem; }
.toggle { margin-left: .4rem; }

.rf { display: inline-block; min-width: 1.5em; text-align: center; font-weight: 700; font-size: .75rem; border-radius: 5px; padding: .05rem .3rem; margin-right: .35rem; color: #fff; }
.rf.r { background: var(--human); } .rf.f { background: var(--ai); }

.story2 { max-width: 1760px; }
.hook { padding: 1.6rem .4rem 1rem; }
.hook h2 { font-size: 2.6rem; line-height: 1.1; margin: 0; }
.hook p { font-size: 1.15rem; color: var(--text-secondary); max-width: 62rem; margin: .6rem 0 0; }
.chapter { display: grid; grid-template-columns: 5fr 7fr; gap: 2rem; align-items: center; padding: 1.6rem .4rem; border-top: 1px solid var(--line); }
.chapter .q { font-size: 1.35rem; margin: 0 0 .2rem; }
.chapter .hero { font-size: 6.2rem; font-weight: 800; line-height: 1; font-variant-numeric: tabular-nums; letter-spacing: -.02em; margin: .3rem 0 .5rem; }
.chapter .hero .from { color: var(--series-2); } .chapter .hero .arrow { color: var(--text-muted); font-weight: 400; margin: 0 .15em; } .chapter .hero .to { color: var(--series-1); }
.chapter .hero.bad { color: var(--series-2); } .chapter .hero.good { color: var(--series-1); }
.chapter .cap { font-size: 1.2rem; margin: 0; max-width: 30rem; }
.chapter .note { margin: .7rem 0 0; padding-left: .8rem; border-left: 4px solid var(--series-2); font-size: 1rem; color: var(--text-secondary); max-width: 30rem; }
.chapter .viz { min-height: 220px; }
.vizhead { display: flex; justify-content: space-between; align-items: center; margin-bottom: .3rem; }
.vizhead span { font-size: .85rem; color: var(--text-secondary); }
.endcards { margin-top: 1rem; }
.endcards ul, .endcards ol { margin: 0; padding-left: 1.2rem; } .endcards li { margin-bottom: .35rem; }
.closing { font-size: 1.4rem; font-weight: 650; text-align: center; padding: 1.8rem 1rem .6rem; max-width: 60rem; margin: 0 auto; }