:root {
  --bg: #0b1020;
  --bg-soft: #121933;
  --card: #151d38;
  --line: #263154;
  --text: #e8ecf7;
  --muted: #9aa6c4;
  --accent: #4c8dff;
  --accent-soft: rgba(76, 141, 255, 0.14);
  --ok: #38d39f;
  --warn: #ffb74d;
  --bad: #ff6b6b;
  --radius: 14px;
  --shadow: 0 18px 40px rgba(4, 8, 20, 0.45);
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

html, body { margin: 0; padding: 0; }

body {
  background:
    radial-gradient(900px 500px at 15% -10%, rgba(76, 141, 255, 0.18), transparent 60%),
    radial-gradient(700px 400px at 95% 0%, rgba(56, 211, 159, 0.10), transparent 55%),
    var(--bg);
  color: var(--text);
  font: 16px/1.55 "Segoe UI", system-ui, -apple-system, Roboto, Arial, sans-serif;
  min-height: 100vh;
}

.wrap { width: min(1060px, 92vw); margin: 0 auto; }

/* ---------------------------------------------------------------- header */

.site-header { padding: 44px 0 18px; }

.site-header h1 {
  margin: 0;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  letter-spacing: -0.03em;
  background: linear-gradient(90deg, #ffffff, #8fb6ff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.tagline { color: var(--muted); margin: 8px 0 0; max-width: 62ch; }

/* ------------------------------------------------------------------ tabs */

.tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.tab {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--muted);
  padding: 9px 16px;
  border-radius: 999px;
  cursor: pointer;
  font: inherit;
  font-size: 0.95rem;
  transition: all 0.15s ease;
}

.tab:hover { color: var(--text); border-color: #37507f; }

.tab.is-active {
  color: #fff;
  border-color: transparent;
  background: linear-gradient(135deg, var(--accent), #6f6bff);
  box-shadow: 0 6px 18px rgba(76, 141, 255, 0.35);
}

/* --------------------------------------------------------------- panels */

main { padding: 24px 0 40px; }

.panel { display: none; }
.panel.is-active { display: block; }

.card {
  background: linear-gradient(180deg, rgba(255,255,255,0.03), transparent 40%), var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
}

.card h2 { margin: 0 0 4px; font-size: 1.3rem; letter-spacing: -0.01em; }

.hint { color: var(--muted); margin: 0 0 20px; font-size: 0.95rem; }

/* ---------------------------------------------------------------- fields */

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 14px;
  margin-bottom: 18px;
}

.field { display: flex; flex-direction: column; gap: 6px; }

.field label { color: var(--muted); font-size: 0.86rem; }

input, select {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  color: var(--text);
  border-radius: 10px;
  padding: 10px 12px;
  font: inherit;
  font-size: 0.98rem;
  width: 100%;
}

input:focus, select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

/* --------------------------------------------------------------- buttons */

.btn {
  background: linear-gradient(135deg, var(--accent), #6f6bff);
  border: 0;
  color: #fff;
  font: inherit;
  font-weight: 600;
  padding: 11px 22px;
  border-radius: 10px;
  cursor: pointer;
  box-shadow: 0 8px 20px rgba(76, 141, 255, 0.3);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}

.btn:hover { transform: translateY(-1px); box-shadow: 0 10px 24px rgba(76, 141, 255, 0.4); }
.btn:active { transform: translateY(0); }

.btn-ghost {
  background: transparent;
  border: 1px solid var(--line);
  box-shadow: none;
  color: var(--text);
}

.btn-ghost:hover { border-color: #37507f; box-shadow: none; }

/* --------------------------------------------------------------- results */

.results { margin-top: 18px; }

.result-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 10px;
}

.result {
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px 14px;
}

.result span { display: block; color: var(--muted); font-size: 0.8rem; }

.result strong { display: block; font-size: 1.18rem; margin-top: 2px; letter-spacing: -0.01em; }

.result.primary { border-color: rgba(76, 141, 255, 0.55); background: var(--accent-soft); }

.badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 999px;
  margin-left: 8px;
  vertical-align: middle;
}

.badge.ok { background: rgba(56, 211, 159, 0.15); color: var(--ok); }
.badge.bad { background: rgba(255, 107, 107, 0.15); color: var(--bad); }
.badge.warn { background: rgba(255, 183, 77, 0.15); color: var(--warn); }

.note { color: var(--muted); font-size: 0.85rem; margin: 16px 0 0; }
.error { color: var(--bad); margin-top: 14px; font-weight: 600; }

.details { margin-top: 20px; border-top: 1px solid var(--line); padding-top: 16px; }
.details summary { cursor: pointer; color: var(--muted); font-weight: 600; margin-bottom: 12px; }

/* --------------------------------------------------------------- stackup */

.stack-head, .stack-row {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 44px;
  gap: 10px;
  align-items: center;
}

.stack-head {
  color: var(--muted);
  font-size: 0.82rem;
  padding: 0 4px 8px;
}

.stack-row { margin-bottom: 10px; }

.stack-row .remove {
  background: transparent;
  border: 1px solid var(--line);
  color: var(--muted);
  border-radius: 10px;
  height: 42px;
  cursor: pointer;
  font-size: 1.1rem;
  line-height: 1;
}

.stack-row .remove:hover { color: var(--bad); border-color: var(--bad); }

.row-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 6px; }

.bar-wrap { margin-top: 6px; }

.bar-row { display: grid; grid-template-columns: 1.2fr 3fr auto; gap: 10px; align-items: center; margin-bottom: 8px; font-size: 0.9rem; }

.bar-track { background: var(--bg-soft); border-radius: 999px; height: 9px; overflow: hidden; }

.bar-fill { height: 100%; background: linear-gradient(90deg, var(--accent), #6f6bff); border-radius: 999px; }

.bar-value { color: var(--muted); font-variant-numeric: tabular-nums; min-width: 52px; text-align: right; }

/* ---------------------------------------------------------------- footer */

.site-footer {
  border-top: 1px solid var(--line);
  padding: 22px 0 40px;
  color: var(--muted);
  font-size: 0.9rem;
}

.site-footer a { color: #8fb6ff; text-decoration: none; }
.site-footer a:hover { text-decoration: underline; }
.fine { font-size: 0.82rem; opacity: 0.8; }

@media (max-width: 620px) {
  .card { padding: 18px; }
  .stack-head { display: none; }
  .stack-row { grid-template-columns: 1fr 1fr; }
  .stack-row .remove { grid-column: span 2; height: 38px; }
}