:root {
  color-scheme: dark;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: #ecf4fa;
  background: #0d1520;
}

* { box-sizing: border-box; }
body { margin: 0; }
a { color: #81d5ff; }
.page { max-width: 1280px; margin: 0 auto; padding: 28px 24px 48px; }
.breadcrumb { margin: 0 0 14px; color: #a9bfd0; font-size: 14px; }
.eyebrow { margin: 0 0 8px; color: #79d0f5; font-size: 12px; font-weight: 700; letter-spacing: .12em; }
h1 { margin: 0 0 8px; font-size: clamp(26px, 3vw, 38px); }
h2 { margin-top: 0; font-size: 18px; }
p { line-height: 1.6; }
.lead { max-width: 760px; margin: 0 0 22px; color: #b5c8d6; }
.workbench { display: grid; grid-template-columns: minmax(0, 1fr) 285px; gap: 22px; align-items: start; }
.stage { position: relative; min-width: 0; aspect-ratio: 16 / 9; overflow: hidden; border: 1px solid #354a5d; border-radius: 16px; background: #142334; }
.stage canvas { display: block; width: 100%; height: 100%; }
.panel { padding: 20px; border: 1px solid #354a5d; border-radius: 16px; background: #172638; }
.control { margin: 18px 0; }
.control label { display: flex; justify-content: space-between; gap: 10px; margin-bottom: 7px; font-size: 14px; }
output { color: #86d8ff; font-variant-numeric: tabular-nums; }
input[type="range"], select { width: 100%; accent-color: #51bce9; }
select { padding: 8px 10px; border: 1px solid #526b80; border-radius: 8px; color: #ecf4fa; background: #21364a; }
.check { display: flex; gap: 9px; align-items: center; margin: 17px 0; font-size: 14px; }
.check input { accent-color: #51bce9; }
.hint, .result { padding: 12px 14px; border-radius: 10px; background: #20374c; color: #c8dbe8; font-size: 13px; line-height: 1.55; }
.result { min-height: 66px; }
.swatches { display: flex; gap: 12px; margin-top: 12px; color: #b5c8d6; font-size: 12px; }
.swatch { display: inline-block; width: 15px; height: 15px; margin-right: 5px; border: 1px solid #8296a6; border-radius: 3px; vertical-align: -3px; }
.quad-labels { position: absolute; inset: 0; display: grid; grid-template-columns: 1fr 1fr; grid-template-rows: 1fr 1fr; pointer-events: none; }
.quad-labels span { padding: 13px 15px; color: white; font-size: clamp(12px, 1.7vw, 16px); font-weight: 700; text-shadow: 0 2px 6px #101923; }
.quad-labels span:nth-child(2), .quad-labels span:nth-child(4) { border-left: 1px solid #8392a0; }
.quad-labels span:nth-child(3), .quad-labels span:nth-child(4) { border-top: 1px solid #8392a0; }
.legend { margin: 16px 0 0; color: #b5c8d6; font-size: 14px; }
.cards { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; }
.card { display: block; padding: 20px; border: 1px solid #354a5d; border-radius: 14px; background: #172638; color: inherit; text-decoration: none; }
.card:hover, .card:focus-visible { border-color: #80d4fa; }
.card strong { display: block; margin-bottom: 8px; font-size: 18px; }
.card span { color: #b5c8d6; line-height: 1.55; }

@media (max-width: 850px) {
  .workbench { grid-template-columns: 1fr; }
  .panel { max-width: none; }
}
@media (max-width: 600px) {
  .page { padding: 18px 12px 32px; }
  .cards { grid-template-columns: 1fr; }
}