:root {
  --concept-accent: var(--blue);
  --concept-soft: #eef3ff;
}

.concept-page.accent-red { --concept-accent: var(--red); --concept-soft: #fff0f0; }
.concept-page.accent-blue { --concept-accent: var(--blue); --concept-soft: #eef3ff; }
.concept-page.accent-yellow { --concept-accent: var(--yellow); --concept-soft: #fff7db; }
.concept-page.accent-black { --concept-accent: var(--black); --concept-soft: #f0f0f1; }
.concept-page .eyebrow span { background: var(--concept-accent); }

.concept-hero { padding-top: 54px; background: linear-gradient(180deg,#fff 0%,#fbfbfa 100%); }
.back-link { display: inline-flex; align-items: center; gap: 8px; margin-bottom: 30px; color: var(--muted); font-weight: 800; }
.back-link:hover { color: var(--concept-accent); }
.concept-hero-grid { display: grid; grid-template-columns: .9fr 1.1fr; align-items: center; gap: 48px; }
.concept-hero-copy h1 { margin: 16px 0 18px; font-size: clamp(54px,7vw,96px); line-height: .9; letter-spacing: -.06em; }
.concept-hero-copy h2 { margin: 0 0 22px; font-size: clamp(28px,3.4vw,46px); line-height: 1.02; letter-spacing: -.035em; }
.concept-lead { margin: 0; max-width: 780px; color: var(--muted); font-size: clamp(18px,2vw,22px); }
.concept-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 28px; }
.concept-tags span { padding: 9px 12px; border-radius: 999px; border: 1px solid var(--line); background: white; font-size: 12px; font-weight: 900; text-transform: uppercase; letter-spacing: .05em; }
.concept-hero-media { margin: 0; overflow: hidden; border: 1px solid var(--line); border-radius: 36px; background: var(--concept-soft); box-shadow: var(--shadow); }
.concept-hero-media img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.concept-facts { display: grid; grid-template-columns: repeat(4,1fr); margin: 48px 0 0; border: 1px solid var(--line); border-radius: 24px; background: white; overflow: hidden; }
.concept-facts div { min-height: 108px; padding: 22px; border-right: 1px solid var(--line); }
.concept-facts div:last-child { border-right: 0; }
.concept-facts dt { margin-bottom: 7px; color: var(--muted); font-size: 12px; font-weight: 900; text-transform: uppercase; letter-spacing: .08em; }
.concept-facts dd { margin: 0; font-size: 18px; font-weight: 900; }

.concept-summary { background: var(--concept-soft); }
.split-copy { display: grid; grid-template-columns: .85fr 1.15fr; gap: 70px; align-items: start; }
.split-copy h2 { margin: 12px 0 0; font-size: clamp(38px,5vw,68px); line-height: .98; letter-spacing: -.045em; }
.split-copy > p { margin: 2px 0 0; color: #34343a; font-size: clamp(18px,2vw,23px); }

.brief-section { background: white; }
.brief-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 16px; }
.brief-card { min-height: 250px; padding: 28px; border: 1px solid var(--line); border-radius: 24px; background: white; }
.brief-card::before { content: ""; display: block; width: 54px; height: 8px; margin-bottom: 42px; border-radius: 99px; background: var(--concept-accent); }
.brief-card h3 { margin: 0 0 12px; font-size: 26px; letter-spacing: -.03em; }
.brief-card p { margin: 0; color: var(--muted); }

.flow-section { background: var(--soft); }
.concept-flow { display: grid; grid-template-columns: repeat(5,1fr); gap: 14px; margin: 0; padding: 0; list-style: none; }
.concept-flow li { position: relative; min-height: 190px; padding: 24px; border: 1px solid var(--line); border-radius: 22px; background: white; }
.concept-flow li:not(:last-child)::after { content: "→"; position: absolute; right: -13px; top: 50%; z-index: 2; transform: translateY(-50%); display: grid; place-items: center; width: 26px; height: 26px; border-radius: 50%; color: white; background: var(--concept-accent); font-weight: 900; }
.concept-flow span { display: inline-grid; place-items: center; width: 48px; height: 48px; border-radius: 14px; color: white; background: var(--concept-accent); font-weight: 900; }
.accent-yellow .concept-flow span,
.accent-yellow .concept-flow li:not(:last-child)::after { color: var(--black); }
.concept-flow p { margin: 34px 0 0; font-size: 18px; font-weight: 900; }

.prototype-section { background: #101014; color: white; }
.prototype-section .section-head p { color: #c9c9ce; }
.prototype-section .eyebrow span { background: var(--yellow); }
.concept-demo { padding: 34px; border: 1px solid #303038; border-radius: 30px; background: #19191e; }
.demo-controls-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 14px; }
.demo-controls-grid label { display: grid; gap: 8px; color: #d4d4d8; font-size: 13px; font-weight: 900; }
.demo-controls-grid select,
.demo-controls-grid input[type="range"] { width: 100%; min-height: 50px; padding: 0 14px; border: 1px solid #3b3b43; border-radius: 14px; color: white; background: #25252b; }
.demo-controls-grid output { display: inline-grid; place-items: center; width: 42px; height: 32px; margin-top: 5px; border-radius: 10px; color: var(--black); background: var(--yellow); font-weight: 900; }
.demo-run { margin-top: 20px; }
.demo-output { min-height: 230px; margin-top: 24px; padding: 28px; border-radius: 24px; color: var(--black); background: linear-gradient(145deg,#fff,#f2f1eb); }
.demo-output:empty::before { content: "Здесь появится результат мини-прототипа."; color: var(--muted); }
.demo-output h3 { margin: 0 0 12px; font-size: clamp(30px,4vw,52px); line-height: 1; letter-spacing: -.045em; }
.demo-output p { max-width: 780px; color: var(--muted); font-size: 18px; }
.demo-output .mini-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 18px; }
.demo-output .mini-tags span { padding: 8px 10px; border: 1px solid var(--line); border-radius: 999px; background: white; font-size: 12px; font-weight: 900; }
.demo-visual-bars { display: flex; align-items: end; gap: 8px; min-height: 90px; margin-top: 24px; }
.demo-visual-bars i { flex: 1; min-width: 26px; border-radius: 10px 10px 4px 4px; background: var(--concept-accent); }
.demo-actions { display: flex; flex-wrap: wrap; gap: 12px; }
.whale-gallery-demo { display: grid; grid-template-columns: repeat(4,1fr); gap: 12px; margin-top: 22px; }
.whale-gallery-demo article { min-height: 150px; padding: 18px; border-radius: 18px; color: var(--black); background: white; }
.whale-gallery-demo b { display: block; margin-bottom: 8px; font-size: 20px; }
.whale-gallery-demo small { color: var(--muted); }
.demo-hint { margin-top: 0; color: #c9c9ce; }
.builder-layout { display: grid; grid-template-columns: 270px 1fr; gap: 20px; }
.builder-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 9px; align-content: start; }
.builder-cards button { min-height: 54px; border: 1px solid #3b3b43; border-radius: 14px; color: white; background: #25252b; cursor: pointer; font-weight: 900; }
.builder-cards button.is-active { color: var(--black); background: var(--yellow); border-color: var(--yellow); }
.builder-board { display: grid; grid-template-columns: repeat(5,1fr); gap: 10px; min-height: 360px; padding: 18px; border-radius: 22px; background: white; }
.builder-board span { display: grid; place-items: center; min-height: 92px; padding: 8px; border-radius: 14px; color: var(--black); background: var(--concept-soft); text-align: center; font-size: 13px; font-weight: 900; }
.demo-score { margin-top: 16px; color: #d7d7dc; font-size: 18px; }

.spec-section { background: white; }
.spec-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 18px; }
.spec-grid article { min-height: 330px; padding: 28px; border: 1px solid var(--line); border-radius: 24px; background: white; }
.spec-grid article:nth-child(2) { background: var(--concept-soft); }
.spec-grid h3 { margin: 0 0 24px; font-size: 28px; letter-spacing: -.03em; }
.spec-grid ul { margin: 0; padding-left: 20px; }
.spec-grid li + li { margin-top: 10px; }
.pilot-note { display: grid; grid-template-columns: 210px 1fr; gap: 28px; margin-top: 20px; padding: 28px; border-radius: 24px; color: white; background: var(--black); }
.pilot-note b { font-size: 22px; }
.pilot-note p { margin: 0; color: #d4d4d8; }

.concept-footer-cta { padding-top: 50px; }
.concept-footer-cta .contact-card { background: var(--concept-accent); }
.accent-yellow .concept-footer-cta .contact-card { color: var(--black); }
.accent-yellow .concept-footer-cta .contact-card p { color: rgba(0,0,0,.7); }
.accent-yellow .outline-light { color: var(--black); border-color: rgba(0,0,0,.3); }

.concept-open { display: inline-flex; align-items: center; gap: 8px; margin-top: 18px; color: var(--blue); font-weight: 900; }
.concept-open::after { content: "→"; }

@media (max-width: 1040px) {
  .concept-hero-grid { grid-template-columns: 1fr; }
  .concept-facts { grid-template-columns: 1fr 1fr; }
  .concept-facts div:nth-child(2) { border-right: 0; }
  .concept-facts div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .split-copy { grid-template-columns: 1fr; gap: 30px; }
  .brief-grid { grid-template-columns: 1fr 1fr; }
  .concept-flow { grid-template-columns: repeat(2,1fr); }
  .concept-flow li:not(:last-child)::after { display: none; }
  .concept-flow li:last-child { grid-column: 1 / -1; }
  .spec-grid { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .concept-hero-copy h1 { font-size: 56px; }
  .concept-facts { grid-template-columns: 1fr; }
  .concept-facts div { border-right: 0; border-bottom: 1px solid var(--line); }
  .concept-facts div:last-child { border-bottom: 0; }
  .brief-grid { grid-template-columns: 1fr; }
  .concept-flow { grid-template-columns: 1fr; }
  .concept-flow li:last-child { grid-column: auto; }
  .demo-controls-grid { grid-template-columns: 1fr; }
  .whale-gallery-demo { grid-template-columns: 1fr 1fr; }
  .builder-layout { grid-template-columns: 1fr; }
  .builder-board { grid-template-columns: repeat(3,1fr); }
  .pilot-note { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .concept-hero-copy h1 { font-size: 46px; }
  .concept-hero-media { border-radius: 24px; }
  .concept-demo { padding: 20px; }
  .whale-gallery-demo { grid-template-columns: 1fr; }
  .builder-board { grid-template-columns: repeat(2,1fr); }
}

/* v4 — interactive organic 3D prototype and Drinkit-oriented details */
.concept-hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(180deg,#fff 0%,#f7f8ff 100%);
}

.concept-hero::after {
  content: "";
  position: absolute;
  right: 4vw;
  top: 36px;
  width: 146px;
  height: 86px;
  opacity: .35;
  background-image: radial-gradient(circle, var(--blue) 0 2px, transparent 2.3px);
  background-size: 17px 17px;
}

.concept-hero .shell { position: relative; z-index: 1; }
.concept-hero-media { border-color: rgba(41,71,255,.14); }
.concept-tags span { border-color: rgba(41,71,255,.16); }

.prototype-section {
  background:
    radial-gradient(circle at 85% 10%, rgba(41,71,255,.28), transparent 27rem),
    #101422;
}

.blob-lab {
  display: grid;
  grid-template-columns: minmax(310px, .72fr) 1.28fr;
  gap: 22px;
  padding: 22px;
  border-color: rgba(255,255,255,.12);
  background: rgba(21,26,44,.9);
}

.blob-sidebar {
  display: flex;
  flex-direction: column;
  gap: 20px;
  padding: 10px;
}

.blob-controls-grid {
  grid-template-columns: 1fr;
}

.blob-actions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.blob-actions .primary { grid-column: 1 / -1; }
.blob-secondary {
  color: white;
  border-color: rgba(255,255,255,.18);
  background: rgba(255,255,255,.06);
}

.blob-result-copy {
  margin-top: auto;
  padding: 22px;
  border: 1px solid rgba(255,255,255,.10);
  border-radius: 22px;
  background: rgba(255,255,255,.055);
}

.blob-result-copy h3 {
  margin: 12px 0;
  font-size: clamp(34px,4.5vw,58px);
  line-height: .94;
  letter-spacing: -.05em;
}

.blob-result-copy p {
  margin: 0;
  color: #cdd2e2;
}

.blob-result-copy .mini-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin-top: 18px;
}

.blob-result-copy .mini-tags span {
  padding: 8px 10px;
  border: 1px solid rgba(255,255,255,.15);
  border-radius: 999px;
  background: rgba(255,255,255,.06);
  font-size: 11px;
  font-weight: 800;
}

.blob-stage {
  position: relative;
  min-height: 690px;
  overflow: hidden;
  border-radius: 26px;
  background: #f6f7ff;
  touch-action: none;
}

.blob-stage-ui {
  position: absolute;
  left: 16px;
  bottom: 16px;
  display: flex;
  gap: 7px;
}

.blob-stage-ui span {
  padding: 8px 10px;
  border: 1px solid rgba(41,71,255,.12);
  border-radius: 10px;
  color: #59617b;
  background: rgba(255,255,255,.78);
  backdrop-filter: blur(10px);
  font-size: 10px;
  font-weight: 900;
}

@media (max-width: 980px) {
  .blob-lab { grid-template-columns: 1fr; }
  .blob-stage { min-height: 570px; order: -1; }
  .blob-controls-grid { grid-template-columns: repeat(3,1fr); }
}

@media (max-width: 760px) {
  .blob-controls-grid { grid-template-columns: 1fr; }
  .blob-stage { min-height: 440px; }
}

@media (max-width: 480px) {
  .blob-lab { padding: 12px; }
  .blob-stage { min-height: 360px; border-radius: 20px; }
  .blob-actions { grid-template-columns: 1fr; }
  .blob-actions .primary { grid-column: auto; }
}

/* v6 — room for PNG + GLB export actions */
.blob-actions {
  grid-template-columns: 1fr 1fr;
}

.blob-actions .primary { grid-column: 1 / -1; }

@media (max-width: 480px) {
  .blob-actions { grid-template-columns: 1fr; }
}