:root {
  --bg: #0a0a0b;
  --bg-soft: #111114;
  --bg-card: #15151a;
  --border: #22222a;
  --text: #e8e8ec;
  --text-dim: #9a9aa3;
  --text-faint: #6a6a73;
  --accent: #5cf2ea;
  --accent-soft: rgba(92, 242, 234, 0.12);
  --warn: #f5b86b;
  --good: #6dd9b1;
  --mid: #e0c97a;
  --bad: #ef7373;
  --max: 1100px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", Helvetica, Arial, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; transition: opacity 0.15s; }
a:hover { opacity: 0.75; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 32px; }

/* nav */
nav {
  position: sticky; top: 0; z-index: 10;
  background: rgba(10, 10, 11, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
nav .wrap {
  display: flex; align-items: center; justify-content: space-between;
  padding-top: 18px; padding-bottom: 18px;
}
.brand {
  font-size: 19px; font-weight: 600; letter-spacing: -0.01em;
  color: var(--text);
}
.brand .dot { color: var(--accent); }
.nav-links { display: flex; gap: 28px; align-items: center; }
.nav-links a {
  color: var(--text-dim); font-size: 14px; font-weight: 500;
}
.nav-links a:hover { color: var(--text); opacity: 1; }
.nav-cta {
  border: 1px solid var(--accent);
  color: var(--accent) !important;
  padding: 10px 18px; border-radius: 6px;
  font-size: 14px; font-weight: 500;
  min-height: 44px;
  display: inline-flex; align-items: center;
}
.nav-cta:hover {
  background: var(--accent-soft); opacity: 1 !important;
}

/* hero */
.hero { padding: 120px 0 100px; }
.eyebrow {
  display: inline-block;
  font-size: 13px; font-weight: 500;
  color: var(--accent); letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 24px;
  padding: 6px 14px; border: 1px solid var(--accent);
  border-radius: 999px;
}
.hero h1 {
  font-size: clamp(40px, 6vw, 72px);
  line-height: 1.05;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 28px;
  max-width: 900px;
}
.hero h1 .accent { color: var(--accent); }
.hero p.lead {
  font-size: 21px; line-height: 1.55;
  color: var(--text-dim);
  max-width: 720px; margin-bottom: 40px;
}
.cta-row { display: flex; gap: 16px; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 14px 26px; border-radius: 8px;
  font-size: 15px; font-weight: 500;
  transition: transform 0.15s, opacity 0.15s, background 0.15s, border-color 0.15s;
  border: 1px solid transparent;
  cursor: pointer;
  min-height: 44px;
  font-family: inherit;
  text-align: center;
  line-height: 1.2;
}
.btn-primary {
  background: var(--accent); color: #08272a !important;
}
.btn-primary:hover { transform: translateY(-1px); opacity: 1; }
.btn-primary:disabled {
  opacity: 0.5; cursor: not-allowed; transform: none;
}
.btn-ghost {
  border: 1px solid var(--border); color: var(--text) !important;
  background: var(--bg-soft);
}
.btn-ghost:hover { border-color: var(--text-dim); opacity: 1; }

/* sections */
section { padding: 80px 0; border-top: 1px solid var(--border); }
section h2 {
  font-size: clamp(28px, 4vw, 40px);
  font-weight: 600; letter-spacing: -0.015em;
  margin-bottom: 16px; max-width: 720px;
}
section p.section-lead {
  font-size: 18px; color: var(--text-dim);
  max-width: 680px; margin-bottom: 40px;
}

/* predict form */
.predict-form {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 28px;
}
.seq-label {
  display: block;
  font-size: 12px; font-weight: 600;
  color: var(--accent); letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 12px;
}
textarea#sequence {
  width: 100%;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px 18px;
  font-family: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Monaco, Consolas, monospace;
  font-size: 14px; line-height: 1.55;
  resize: vertical;
  min-height: 200px;
  outline: none;
  transition: border-color 0.15s;
}
textarea#sequence::placeholder { color: var(--text-faint); }
textarea#sequence:focus { border-color: var(--accent); }

.form-actions {
  display: flex; gap: 12px; flex-wrap: wrap;
  margin-top: 20px;
}
.status {
  margin-top: 16px;
  font-size: 13px; color: var(--text-faint);
}

/* sample sequence buttons */
.sample-row {
  margin-top: 18px;
  display: flex; flex-wrap: wrap; gap: 8px; align-items: center;
}
.sample-label {
  font-size: 13px;
  color: var(--text-faint);
  margin-right: 4px;
}
.sample-btn {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-dim);
  padding: 6px 12px;
  font-size: 13px;
  border-radius: 6px;
  cursor: pointer;
  font-family: inherit;
  transition: border-color 0.12s, color 0.12s;
}
.sample-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

/* feedback card */
.feedback-card {
  margin-top: 32px;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 22px 26px;
}
.feedback-head strong {
  display: block;
  font-size: 16px;
  color: var(--text);
  margin-bottom: 4px;
}
.feedback-head p {
  font-size: 14px;
  color: var(--text-dim);
  margin: 0 0 16px;
}
.feedback-actions {
  display: flex; flex-wrap: wrap; gap: 10px;
  margin-bottom: 12px;
}
.feedback-btn {
  display: inline-flex; align-items: center; gap: 6px;
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
  padding: 9px 16px;
  font-size: 14px;
  font-family: inherit;
  border-radius: 6px;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, color 0.15s;
  min-height: 40px;
}
.feedback-btn:hover:not(:disabled) {
  border-color: var(--text-dim);
}
.feedback-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}
.feedback-btn.worked:hover:not(:disabled) {
  border-color: var(--good);
  color: var(--good);
}
.feedback-btn.failed:hover:not(:disabled) {
  border-color: var(--bad);
  color: var(--bad);
}
.feedback-btn .fb-icon { font-weight: 600; }
.feedback-meta {
  font-size: 12px;
  color: var(--text-faint);
  margin: 0;
}
.feedback-thanks {
  margin-top: 28px;
  background: rgba(109, 217, 177, 0.08);
  border: 1px solid rgba(109, 217, 177, 0.35);
  border-left: 3px solid var(--good);
  border-radius: 6px;
  padding: 14px 18px;
  font-size: 14px;
  color: var(--text);
}
.feedback-thanks strong { color: var(--good); }

/* OOD warning */
.ood-warning {
  margin-top: 20px;
  background: rgba(245, 184, 107, 0.07);
  border: 1px solid rgba(245, 184, 107, 0.35);
  border-left: 3px solid var(--warn);
  border-radius: 6px;
  padding: 14px 18px;
  font-size: 14px;
  color: var(--text);
  line-height: 1.55;
}
.ood-warning strong { color: var(--warn); }

/* spinner inside button */
.btn-spinner {
  display: none;
  width: 16px; height: 16px;
  margin-left: 10px;
  border: 2px solid rgba(8, 39, 42, 0.35);
  border-top-color: #08272a;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}
.btn.is-loading .btn-spinner { display: inline-block; }
.btn.is-loading .btn-label { opacity: 0.85; }
@keyframes spin { to { transform: rotate(360deg); } }

/* error box */
.error-box {
  margin-top: 24px;
  background: rgba(239, 115, 115, 0.07);
  border: 1px solid rgba(239, 115, 115, 0.4);
  border-left: 3px solid var(--bad);
  border-radius: 8px;
  padding: 18px 22px;
  color: var(--text);
  font-size: 15px;
  line-height: 1.5;
}
.error-box strong { color: var(--bad); display: block; margin-bottom: 4px; }

/* results */
.results {
  margin-top: 32px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 32px;
}
.result-head {
  display: flex; justify-content: space-between; align-items: flex-start;
  gap: 24px; flex-wrap: wrap;
  margin-bottom: 20px;
}
.result-eyebrow {
  font-size: 12px; font-weight: 600;
  color: var(--accent); letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 8px;
}
#result-label {
  font-size: 28px; font-weight: 600;
  letter-spacing: -0.015em;
}
.result-ci {
  margin-top: 6px;
  font-size: 14px; color: var(--text-dim);
}
.score-block {
  display: flex; align-items: baseline; gap: 6px;
}
.score-num {
  font-size: 56px; font-weight: 600;
  letter-spacing: -0.03em;
  font-variant-numeric: tabular-nums;
  color: var(--text);
  line-height: 1;
}
.score-num.good { color: var(--good); }
.score-num.mid { color: var(--mid); }
.score-num.bad { color: var(--bad); }
.score-cap { font-size: 18px; color: var(--text-faint); }

.bar-wrap {
  height: 10px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 999px;
  overflow: hidden;
  margin-bottom: 32px;
}
.bar-fill {
  height: 100%;
  width: 0%;
  background: var(--good);
  border-radius: 999px;
  transition: width 0.6s ease, background 0.3s;
}
.bar-fill.good { background: var(--good); }
.bar-fill.mid  { background: var(--mid); }
.bar-fill.bad  { background: var(--bad); }

.sub {
  font-size: 13px; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase;
  color: var(--text-dim);
  margin-bottom: 14px;
}

.risk-grid {
  display: grid; gap: 14px;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  margin-bottom: 32px;
}
.risk-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px 18px;
}
.risk-card .rname {
  font-size: 14px; color: var(--text-dim);
  margin-bottom: 6px;
}
.risk-card .rval {
  font-size: 16px; color: var(--text); font-weight: 500;
  margin-bottom: 10px;
  line-height: 1.4;
}
.risk-pill {
  display: inline-block;
  font-size: 11px; font-weight: 600;
  letter-spacing: 0.06em; text-transform: uppercase;
  padding: 3px 9px; border-radius: 999px;
}
.risk-pill.low  { background: #1c2a26; color: var(--good); }
.risk-pill.medium, .risk-pill.mod { background: #2a2818; color: var(--mid); }
.risk-pill.high { background: #2d2018; color: #f0a36b; }
.risk-pill.critical, .risk-pill.crit { background: #2e1818; color: var(--bad); }
.risk-pill.unknown { background: #1d2530; color: #7eb1d9; }

.recs {
  list-style: none;
  margin-bottom: 24px;
}
.recs li {
  font-size: 15px; color: var(--text);
  padding: 8px 0 8px 22px;
  position: relative;
  line-height: 1.55;
  border-bottom: 1px solid var(--border);
}
.recs li:last-child { border-bottom: none; }
.recs li:before {
  content: ""; position: absolute;
  left: 0; top: 17px;
  width: 6px; height: 6px;
  background: var(--accent); border-radius: 50%;
}

.model-version {
  font-size: 12px; color: var(--text-faint);
  margin-bottom: 20px;
  letter-spacing: 0.04em;
}

/* how it works cards */
.cards { display: grid; gap: 20px; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px;
}
.card .step {
  display: inline-block;
  font-size: 12px; font-weight: 600; color: var(--accent);
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}
.card h3 {
  font-size: 19px; font-weight: 600;
  margin-bottom: 12px; letter-spacing: -0.01em;
}
.card p {
  font-size: 15px; color: var(--text-dim);
  line-height: 1.6;
}

/* about disclaimer */
.disclaimer {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 20px 24px; margin-top: 8px;
  font-size: 15px; color: var(--text-dim); line-height: 1.6;
}
.disclaimer strong { color: var(--text); }

/* footer */
footer {
  border-top: 1px solid var(--border);
  padding: 40px 0 56px;
  margin-top: 40px;
}
footer .wrap {
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 16px;
}
footer p { font-size: 13px; color: var(--text-faint); }

@media (max-width: 640px) {
  .wrap { padding: 0 20px; }
  .hero { padding: 70px 0 60px; }
  section { padding: 60px 0; }
  .nav-links { gap: 14px; }
  .nav-links a:not(.nav-cta) { display: none; }
  .predict-form, .results { padding: 20px; }
  .form-actions .btn { width: 100%; }
  .score-num { font-size: 44px; }
}