.concept-ribbon {
  position: relative;
  z-index: 30;
  padding: 7px var(--pad);
  text-align: center;
  color: #061a2d;
  background: var(--accent);
}

.concept-hero {
  min-height: auto;
  padding: clamp(76px, 9vw, 128px) 0;
}

.concept-hero::after {
  content: "";
  position: absolute;
  width: min(48vw, 660px);
  aspect-ratio: 1;
  right: -16vw;
  top: -26%;
  border-radius: 50%;
  background: radial-gradient(circle, color-mix(in oklab, var(--accent) 20%, transparent), transparent 67%);
  pointer-events: none;
}

.concept-hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1.04fr) minmax(420px, .96fr);
  gap: clamp(48px, 7vw, 100px);
  align-items: center;
}

.concept-hero-copy h1 {
  max-width: 780px;
  margin: 18px 0 24px;
  font-family: var(--serif);
  font-size: clamp(48px, 6.7vw, 88px);
  font-weight: 400;
  line-height: .96;
  letter-spacing: -.035em;
  text-wrap: balance;
}

.hero-support {
  max-width: 70ch;
  margin: 16px 0 0;
  color: var(--fg-3);
  line-height: 1.7;
}

.hero-proof {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin-top: 30px;
  color: var(--fg-3);
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .05em;
}

.hero-proof span {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.hero-proof span::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}

.memory-map {
  position: relative;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: clamp(22px, 3vw, 34px);
  background: color-mix(in oklab, var(--bg-2) 90%, transparent);
  box-shadow: 0 28px 80px rgba(0, 0, 0, .15);
}

.memory-map::before {
  content: "";
  position: absolute;
  inset: 10px;
  border: 1px solid var(--line-2);
  border-radius: 8px;
  pointer-events: none;
}

.memory-map-head,
.level-top,
.start-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.status-dot {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--accent-text);
  font-size: 12px;
}

.status-dot::before {
  content: "";
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 5px color-mix(in oklab, var(--accent) 14%, transparent);
}

.memory-problem {
  display: grid;
  gap: 7px;
  margin-top: 28px;
  padding: 19px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: var(--bg);
}

.memory-problem span,
.memory-records small,
.memory-result small { color: var(--fg-3); }

.memory-flow {
  display: grid;
  grid-template-columns: auto 1fr auto 1fr auto;
  gap: 10px;
  align-items: center;
  padding: 22px 5px;
  color: var(--fg-3);
  font-family: var(--mono);
  font-size: 10px;
  text-transform: uppercase;
}

.memory-flow i { height: 1px; background: linear-gradient(90deg, var(--accent), var(--line)); }

.memory-records {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
}

.memory-records article {
  display: grid;
  gap: 7px;
  min-height: 96px;
  padding: 15px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: var(--bg-3);
}

.memory-records strong { font-size: 13px; line-height: 1.35; }

.memory-result {
  display: flex;
  align-items: center;
  gap: 15px;
  margin-top: 18px;
  padding: 17px;
  border: 1px solid color-mix(in oklab, var(--accent) 55%, var(--line));
  border-radius: 7px;
  background: var(--soft-accent);
}

.memory-result div { display: grid; gap: 3px; }
.memory-result strong { font-size: 13px; }
.pulse { width: 12px; height: 12px; flex: 0 0 12px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 0 7px color-mix(in oklab, var(--accent) 18%, transparent); }

.problem-grid,
.continuity-grid,
.access-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.problem-card,
.continuity-grid article,
.access-grid article,
.security-grid article {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 26px;
  background: var(--bg);
}

.problem-card span { color: var(--accent-text); }
.problem-card h3,
.continuity-grid h3,
.access-grid h3,
.security-grid h3 { margin: 18px 0 10px; font-size: 19px; line-height: 1.3; }
.problem-card p,
.continuity-grid p,
.access-grid p,
.security-grid p { margin: 0; color: var(--fg-2); line-height: 1.65; }

.value-chain {
  border-top: 1px solid var(--line);
}

.value-chain article {
  display: grid;
  grid-template-columns: 78px minmax(0, 1fr);
  gap: 20px;
  padding: 26px 0;
  border-bottom: 1px solid var(--line);
}

.chain-index,
.level-number {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent-text);
}

.value-chain h3 { margin: 0 0 8px; font-family: var(--serif); font-size: 25px; font-weight: 400; }
.value-chain p { max-width: 75ch; margin: 0; color: var(--fg-2); }

.statement {
  margin: 34px 0 0;
  padding: 24px;
  border-left: 3px solid var(--accent);
  background: var(--soft-accent);
  font-family: var(--serif);
  font-size: clamp(21px, 2vw, 28px);
}

.level-grid,
.start-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.level-card,
.start-card {
  position: relative;
  padding: clamp(26px, 4vw, 42px);
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  overflow: hidden;
}

.level-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: var(--line);
}

.level-proof::before { background: var(--accent); }

.pill {
  display: inline-flex;
  width: fit-content;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--fg-2);
  background: var(--bg-2);
  font-family: var(--mono);
  font-size: 10px;
  line-height: 1.2;
  text-transform: uppercase;
}

.level-card h3,
.start-card h3 { margin: 30px 0 14px; font-family: var(--serif); font-size: clamp(30px, 3vw, 42px); font-weight: 400; }
.level-card > p { color: var(--fg-2); line-height: 1.7; }

.check-list {
  display: grid;
  gap: 11px;
  margin: 24px 0;
  padding: 0;
  list-style: none;
}

.check-list li { position: relative; padding-left: 25px; color: var(--fg-2); }
.check-list li::before { content: "✓"; position: absolute; left: 0; color: var(--accent-text); font-weight: 700; }
.level-note { padding-top: 20px; border-top: 1px solid var(--line); font-size: 14px; }

.mode-tabs {
  display: inline-grid;
  grid-template-columns: repeat(2, auto);
  gap: 4px;
  margin-bottom: 24px;
  padding: 4px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg);
}

.mode-toggle {
  position: absolute;
  inline-size: 1px;
  block-size: 1px;
  opacity: 0;
  pointer-events: none;
}

.mode-tab {
  min-height: 42px;
  padding: 0 18px;
  border: 0;
  border-radius: 5px;
  color: var(--fg-2);
  background: transparent;
  cursor: pointer;
}

.mode-panel { display: none; }
#mode-model:checked ~ .mode-tabs .mode-tab-model,
#mode-proof:checked ~ .mode-tabs .mode-tab-proof { color: #061a2d; background: var(--accent); font-weight: 650; }
#mode-model:checked ~ .mode-panel-model,
#mode-proof:checked ~ .mode-panel-proof { display: block; }

.step-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  border: 1px solid var(--line);
  border-radius: 9px;
  overflow: hidden;
}

.step-grid article { padding: 28px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--bg); }
.step-grid article:nth-child(2n) { border-right: 0; }
.step-grid article:nth-last-child(-n + 2) { border-bottom: 0; }
.step-grid span { display: grid; place-items: center; width: 30px; height: 30px; border-radius: 50%; background: var(--soft-accent); color: var(--accent-text); font-family: var(--mono); font-size: 11px; }
.step-grid h3 { margin: 18px 0 9px; font-size: 19px; }
.step-grid p { margin: 0; color: var(--fg-2); line-height: 1.65; }
.two-steps article { border-bottom: 0; }

.next-question {
  margin: 24px 0 0;
  padding: 24px clamp(22px, 4vw, 40px);
  border: 0;
  border-left: 3px solid var(--accent);
  background: var(--bg);
}
.next-question span { color: var(--accent-text); }
.next-question p { margin: 9px 0 0; font-family: var(--serif); font-size: clamp(21px, 2.6vw, 32px); line-height: 1.3; }
.fineprint { color: var(--fg-4); font-size: 13px; }

.gap-board {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  gap: 18px;
  align-items: stretch;
}

.gap-board article { padding: 25px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); }
.gap-board span { color: var(--accent-text); }
.gap-board h3 { margin: 17px 0 9px; font-size: 19px; }
.gap-board p { margin: 0; color: var(--fg-2); line-height: 1.6; }
.gap-arrow { display: grid; place-items: center; color: var(--accent-text); font-size: 22px; }

.scope-note {
  margin: 24px 0 0;
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: 7px;
  color: var(--fg-2);
  background: var(--bg-2);
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.product-shot {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 9px;
  background: var(--bg);
  overflow: hidden;
}

.product-shot-wide { grid-column: 1 / -1; }
.product-shot figcaption { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 86px; padding: 18px 20px; border-bottom: 1px solid var(--line); }
.product-shot figcaption > span:first-child { display: grid; gap: 4px; }
.product-shot small { color: var(--fg-3); }
.product-shot .screen-frame { display: block; min-height: 250px; max-height: 510px; overflow: hidden; background: var(--bg-3); }
.product-shot img { width: 100%; height: 100%; display: block; object-fit: cover; object-position: top; }
.section-actions { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 30px; }

.continuity-icon {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 50%;
  color: var(--accent-text);
  font-family: var(--mono);
}

.access-grid article { position: relative; padding-top: 70px; }
.access-code { position: absolute; top: 24px; left: 26px; color: var(--accent-text); font-family: var(--mono); font-size: 11px; letter-spacing: .08em; }

.security-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}
.security-grid h3 { margin-top: 0; }

.question-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}
.question-grid article { min-height: 190px; padding: 28px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg); }
.question-grid span { color: var(--accent-text); font-family: var(--mono); font-size: 11px; text-transform: uppercase; letter-spacing: .06em; }
.question-grid p { margin: 34px 0 0; font-family: var(--serif); font-size: clamp(20px, 2.1vw, 28px); line-height: 1.35; }

.start-head { justify-content: flex-start; align-items: flex-start; }
.start-head .level-number { display: grid; place-items: center; width: 38px; height: 38px; flex: 0 0 38px; border: 1px solid var(--line); border-radius: 50%; }
.start-head h3 { margin: 7px 0 0; font-size: clamp(25px, 2.5vw, 34px); }
.start-subtitle { margin: 22px 0; color: var(--accent-text); font-weight: 650; }
.start-card ol { display: grid; gap: 12px; margin: 0; padding-left: 22px; color: var(--fg-2); }
.deliverable { margin: 26px 0 0; padding-top: 22px; border-top: 1px solid var(--line); color: var(--fg-2); }

.faq-layout {
  display: grid;
  grid-template-columns: .75fr 1.25fr;
  gap: clamp(38px, 7vw, 100px);
  align-items: start;
}
.faq-layout .section-title { margin-top: 18px; }
.faq-list { border-top: 1px solid var(--line); }
.faq-list details { border-bottom: 1px solid var(--line); }
.faq-list summary { position: relative; padding: 22px 48px 22px 0; cursor: pointer; list-style: none; font-weight: 650; }
.faq-list summary::-webkit-details-marker { display: none; }
.faq-list summary::after { content: "+"; position: absolute; top: 19px; right: 4px; color: var(--accent-text); font-size: 24px; font-weight: 300; }
.faq-list details[open] summary::after { content: "−"; }
.faq-list details p { margin: -4px 0 24px; color: var(--fg-2); line-height: 1.7; }

#concept-contact a { text-decoration: underline; text-underline-offset: 2px; }
.form-msg-preview { color: var(--accent-text); margin-bottom: 12px; }

.widget-language-note {
  position: fixed;
  right: 18px;
  bottom: 84px;
  z-index: 900;
  max-width: 250px;
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: color-mix(in srgb, var(--bg) 94%, transparent);
  color: var(--fg-2);
  box-shadow: 0 8px 24px rgba(0, 0, 0, .18);
  font-size: 12px;
  line-height: 1.4;
  pointer-events: none;
}

html[lang="tr"] .widget-language-note { display: none; }

@media (max-width: 1120px) {
  .nav-links { gap: 13px; font-size: 13px; }
  .nav-demo { display: none; }
}

@media (max-width: 980px) {
  .concept-hero-grid { grid-template-columns: 1fr; }
  .memory-map { max-width: 680px; }
  .problem-grid,
  .continuity-grid,
  .access-grid,
  .security-grid { grid-template-columns: repeat(2, 1fr); }
  .gap-board { grid-template-columns: 1fr; }
  .gap-arrow { transform: rotate(90deg); }
  .faq-layout { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .concept-ribbon { padding-inline: 12px; }
  .concept-hero-copy h1 { font-size: clamp(44px, 14vw, 66px); }
  .memory-records { grid-template-columns: 1fr; }
  .memory-flow { grid-template-columns: 1fr; text-align: center; }
  .memory-flow i { width: 1px; height: 16px; margin: auto; }
  .problem-grid,
  .continuity-grid,
  .access-grid,
  .security-grid,
  .level-grid,
  .start-grid,
  .step-grid,
  .question-grid,
  .product-grid { grid-template-columns: 1fr; }
  .step-grid article,
  .step-grid article:nth-child(2n),
  .step-grid article:nth-last-child(-n + 2) { border-right: 0; border-bottom: 1px solid var(--line); }
  .step-grid article:last-child { border-bottom: 0; }
  .product-shot-wide { grid-column: auto; }
  .mode-tabs { display: grid; grid-template-columns: 1fr; width: 100%; }
  .product-shot figcaption { align-items: flex-start; flex-direction: column; }
  .hero-proof { display: grid; }
}