:root {
  --ink: #0E1B2B;
  --panel: #16273B;
  --panel-line: #274257;
  --chalk: #EDEFF2;
  --steel: #8FA3B8;
  --cyan: #4FB8C4;
  --amber: #E8A33D;
  --green: #6FBF8B;
  --font-display: "Fraunces", serif;
  --font-body: "Inter", sans-serif;
  --font-mono: "IBM Plex Mono", monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--ink);
  background-image:
    linear-gradient(rgba(79,184,196,0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(79,184,196,0.045) 1px, transparent 1px);
  background-size: 42px 42px;
  color: var(--chalk);
  font-family: var(--font-body);
  line-height: 1.55;
  min-height: 100vh;
}

@media (prefers-reduced-motion: reduce) {
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

.scanline {
  position: fixed; inset: 0; pointer-events: none; z-index: 0;
  background: radial-gradient(ellipse at top, rgba(79,184,196,0.06), transparent 60%);
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  max-width: 900px;
  margin: 0 auto;
  padding: 64px 24px 24px;
  text-align: center;
}
.hero-inner { position: relative; z-index: 1; }
.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--cyan);
  margin: 0 0 18px;
}
.hero h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(30px, 5vw, 48px);
  line-height: 1.12;
  margin: 0 0 20px;
  color: var(--chalk);
}
.lede {
  color: var(--steel);
  font-size: 16px;
  max-width: 620px;
  margin: 0 auto;
}
.hero-chain {
  width: 100%;
  max-width: 900px;
  height: auto;
  display: block;
  margin: 28px auto 0;
}

/* ---------- Layout ---------- */
main {
  position: relative;
  z-index: 1;
  max-width: 760px;
  margin: 0 auto;
  padding: 24px 20px 80px;
}

.stage { display: none; }
.stage.active { display: block; animation: fadeUp 0.35s ease; }
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.stage-card {
  background: var(--panel);
  border: 1px solid var(--panel-line);
  border-radius: 14px;
  padding: 32px;
}
.stage-card.wide { padding: 32px 36px; }

.stage-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--cyan);
  margin: 0 0 20px;
}

label {
  display: block;
  font-size: 13px;
  color: var(--steel);
  margin: 20px 0 8px;
}
label:first-of-type { margin-top: 0; }
.optional { color: #5C7086; font-style: italic; }

input[type="text"], textarea {
  width: 100%;
  background: #0E1B2B;
  border: 1px solid var(--panel-line);
  border-radius: 8px;
  padding: 12px 14px;
  color: var(--chalk);
  font-family: var(--font-body);
  font-size: 15px;
  resize: vertical;
}
input[type="text"]:focus, textarea:focus {
  outline: 2px solid var(--cyan);
  outline-offset: 1px;
  border-color: var(--cyan);
}

.btn-primary, .btn-secondary {
  margin-top: 26px;
  padding: 13px 22px;
  border-radius: 8px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 15px;
  cursor: pointer;
  border: none;
  transition: transform 0.12s ease, background 0.15s ease;
}
.btn-primary {
  background: var(--cyan);
  color: #08151F;
}
.btn-primary:hover { background: #63c7d2; transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }

.btn-secondary {
  background: transparent;
  border: 1px solid var(--panel-line);
  color: var(--chalk);
}
.btn-secondary:hover { border-color: var(--cyan); color: var(--cyan); }

.error-msg {
  color: #E87A5D;
  font-size: 13.5px;
  margin-top: 12px;
  min-height: 0;
}

/* ---------- Loading ---------- */
.loading-block {
  text-align: center;
  padding: 90px 20px;
  color: var(--steel);
}
.pulse-dot {
  width: 14px; height: 14px;
  border-radius: 50%;
  background: var(--cyan);
  margin: 0 auto 20px;
  animation: pulse 1.1s ease-in-out infinite;
}
.pulse-dot.amber { background: var(--amber); }
@keyframes pulse {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.6); opacity: 0.5; }
}

/* ---------- Chain viz ---------- */
.chain-viz {
  overflow-x: auto;
  padding: 10px 0 22px;
  margin-bottom: 8px;
}

/* ---------- Questions ---------- */
.questions-list { margin-top: 8px; }
.question-block {
  border-top: 1px solid var(--panel-line);
  padding: 20px 0;
}
.question-block:first-child { border-top: none; }
.q-concept-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--cyan);
  border: 1px solid var(--cyan);
  border-radius: 4px;
  padding: 2px 8px;
  margin-bottom: 10px;
}
.q-text {
  font-size: 15.5px;
  margin: 0 0 12px;
  color: var(--chalk);
}
.q-answer {
  width: 100%;
  min-height: 70px;
}

h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 24px;
  margin: 0 0 6px;
}
h3 {
  font-family: var(--font-body);
  font-size: 14px;
  color: var(--steel);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin: 0 0 12px;
}

/* ---------- Result ---------- */
.verdict-card {
  background: #12202f;
  border: 1px solid var(--amber);
  border-radius: 10px;
  padding: 22px 24px;
  margin: 18px 0 30px;
}
.verdict-card.clean { border-color: var(--green); }
.verdict-title {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--amber);
  margin: 0 0 8px;
}
.verdict-card.clean .verdict-title { color: var(--green); }
.verdict-concept {
  font-family: var(--font-display);
  font-size: 21px;
  font-weight: 600;
  margin: 0 0 10px;
}
.verdict-explain { color: var(--steel); margin: 0; font-size: 15px; }

.result-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
  margin-bottom: 10px;
}
@media (max-width: 620px) {
  .result-columns { grid-template-columns: 1fr; }
}
#result-order { margin: 0; padding-left: 20px; color: var(--chalk); }
#result-order li { margin-bottom: 8px; }
#result-order li.gap-item { color: var(--amber); font-weight: 600; }
.next-step {
  background: #0E1B2B;
  border: 1px solid var(--panel-line);
  border-radius: 8px;
  padding: 14px 16px;
  color: var(--chalk);
  font-size: 15px;
  margin: 0;
}

footer {
  text-align: center;
  color: #52667B;
  font-size: 13px;
  padding: 20px;
  position: relative;
  z-index: 1;
}

/* ---------- Node chain SVG (rendered via JS) ---------- */
.node-label {
  font-family: var(--font-mono);
  font-size: 11px;
  fill: var(--steel);
}