:root {
  --bg: #0a0a0f;
  --card: #12121a;
  --card-2: #171722;
  --text: #f1f5f9;
  --muted: #8b91a3;
  --accent: #7c9cff;
  --accent-2: #5ee0b0;
  --danger: #ff6b6b;
  --border: #23232f;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, monospace;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: radial-gradient(1200px 600px at 50% -10%, #16162400 0%, var(--bg) 60%), var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.55;
  min-height: 100vh;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.site-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 18px 24px; border-bottom: 1px solid var(--border);
  position: sticky; top: 0; backdrop-filter: blur(8px); background: rgba(10,10,15,.7); z-index: 5;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 1.15rem; }
.logo { font-size: 1.4rem; }
.brand-name { letter-spacing: -.02em; }
.ghlink { font-size: .9rem; color: var(--muted); }

main { max-width: 940px; margin: 0 auto; padding: 32px 20px 64px; }

.hero { text-align: center; padding: 28px 0 34px; }
.hero h1 { font-size: clamp(1.6rem, 4vw, 2.5rem); line-height: 1.15; margin: 0 0 14px; letter-spacing: -.03em; }
.accent { background: linear-gradient(90deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero .sub { color: var(--muted); max-width: 620px; margin: 0 auto; font-size: 1.05rem; }

.card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: 16px; padding: 22px; margin-bottom: 20px;
  box-shadow: 0 1px 0 rgba(255,255,255,.02) inset, 0 20px 40px -30px rgba(0,0,0,.8);
}

.expr-label { display: block; font-size: .8rem; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin-bottom: 8px; }
.expr-row { display: flex; gap: 10px; }
.expr-input {
  flex: 1; font-family: var(--mono); font-size: 1.35rem; letter-spacing: .04em;
  background: var(--card-2); border: 1px solid var(--border); color: var(--text);
  border-radius: 10px; padding: 14px 16px; outline: none; transition: border-color .15s;
}
.expr-input:focus { border-color: var(--accent); }
.tz-select {
  background: var(--card-2); border: 1px solid var(--border); color: var(--text);
  border-radius: 10px; padding: 0 12px; font-size: .95rem;
}
.explanation { font-size: 1.25rem; margin: 16px 0 4px; color: var(--accent-2); font-weight: 500; }
.error { color: var(--danger); font-family: var(--mono); font-size: .95rem; margin: 8px 0 0; }

.presets { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 16px; }
.preset {
  background: var(--card-2); border: 1px solid var(--border); color: var(--muted);
  border-radius: 999px; padding: 6px 14px; font-size: .85rem; cursor: pointer; transition: all .15s;
}
.preset:hover { color: var(--text); border-color: var(--accent); }

.grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
@media (max-width: 760px) { .grid { grid-template-columns: 1fr; } }

h2 { font-size: 1rem; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); margin: 0 0 14px; }

.timeline { list-style: none; margin: 0; padding: 0; }
.timeline li { display: flex; align-items: center; gap: 12px; padding: 9px 0; border-bottom: 1px dashed var(--border); font-family: var(--mono); font-size: .92rem; }
.timeline li:last-child { border-bottom: none; }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--accent-2); box-shadow: 0 0 8px var(--accent-2); flex: none; }
.ts { flex: 1; }
.rel { color: var(--muted); font-size: .82rem; }
.timeline .none { color: var(--danger); font-family: var(--mono); }

.tabs { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.tab { background: var(--card-2); border: 1px solid var(--border); color: var(--muted); border-radius: 8px; padding: 5px 10px; font-size: .78rem; font-family: var(--mono); cursor: pointer; }
.tab.active { color: var(--bg); background: var(--accent); border-color: var(--accent); font-weight: 600; }
.export-out { background: #0d0d14; border: 1px solid var(--border); border-radius: 10px; padding: 14px; overflow: auto; max-height: 260px; margin: 0; }
.export-out code { font-family: var(--mono); font-size: .82rem; color: #cdd3e0; white-space: pre; }
.copy-btn { margin-top: 12px; background: var(--card-2); border: 1px solid var(--border); color: var(--text); border-radius: 8px; padding: 8px 16px; cursor: pointer; font-size: .85rem; }
.copy-btn:hover { border-color: var(--accent); }

.cmp { width: 100%; border-collapse: collapse; font-size: .92rem; }
.cmp th, .cmp td { text-align: left; padding: 10px 12px; border-bottom: 1px solid var(--border); }
.cmp thead th { color: var(--muted); font-weight: 600; text-transform: none; letter-spacing: 0; }
.cmp .us { color: var(--accent-2); }
.cmp th.us { color: var(--accent-2); }

.site-footer { text-align: center; color: var(--muted); font-size: .85rem; padding: 32px 20px 48px; border-top: 1px solid var(--border); }