/* ──────────────────────────────────────────────────────────────
   Box Spread Calculator — styles
   Maps onto shared /assets/tokens.css brand tokens.
   ────────────────────────────────────────────────────────────── */
:root {
  --bg:        var(--brand-bg);
  --bg-2:      var(--brand-bg-2);
  --surface:   var(--brand-surface);
  --border:    var(--brand-border);
  --text:      var(--brand-text);
  --muted:     var(--brand-text-muted);
  --accent:    var(--brand-accent);
  --accent-2:  var(--brand-accent-2);
  --font-display: var(--brand-font-display);
  --font-head: var(--brand-font-head);
  --font-body: var(--brand-font-body);
  --font-mono: var(--brand-font-mono);
  --spot-gold: var(--brand-gold);   /* brand spotlight gold (semantic --gold below stays local) */
  --ease:      var(--brand-ease);

  /* semantic */
  --up:      #22c55e;
  --down:    #ef4444;
  --gold:    #fbbf24;
  --info-bg:    rgba(99,102,241,0.12);
  --info-text:  #c7d2fe;
  --warn-bg:    rgba(239,68,68,0.12);
  --warn-text:  #fca5a5;
  --good-bg:    rgba(34,197,94,0.12);
  --good-text:  #86efac;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
.hidden { display: none !important; }

body {
  font-family: var(--font-body);
  background:
    radial-gradient(900px 480px at 50% -10%, rgba(99,102,241,0.10), transparent 60%),
    var(--bg);
  color: var(--text);
  min-height: 100vh;
  padding: 28px 20px 60px;
  line-height: 1.5;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 780px; margin: 0 auto; }

.glass {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  backdrop-filter: blur(10px);
}

/* ── Hero ───────────────────────────────────────────────── */
.hero {
  display: flex; justify-content: space-between; align-items: flex-start;
  padding: 22px 26px; margin-bottom: 18px; gap: 16px; flex-wrap: wrap;
  background: linear-gradient(135deg, rgba(99,102,241,0.14), rgba(139,92,246,0.05));
}
.back-link {
  font-size: 12px; color: var(--muted);
  transition: color .15s var(--ease);
}
.back-link:hover { color: var(--text); text-decoration: none; }
h1 {
  font-family: var(--font-display); font-style: italic; font-size: 30px; font-weight: 400;
  letter-spacing: 0.01em; margin: 4px 0 2px;
}
.hero-sub { font-size: 13px; color: var(--muted); }
.hero-sub.warn { color: var(--down); }

.tsy-box { text-align: right; flex-shrink: 0; }
.tsy-label {
  font-size: 10px; color: var(--muted);
  text-transform: uppercase; letter-spacing: .08em;
}
.tsy-val {
  font-size: 20px; font-weight: 700; font-family: var(--font-head);
  font-variant-numeric: tabular-nums; margin-top: 2px;
}
.tsy-meta { font-size: 11px; color: var(--muted); margin-top: 2px; }

/* ── Borrow amount selector ──────────────────────────────── */
.panel.borrow-panel { text-align: center; padding: 22px 18px; }
.borrow-row {
  display: flex; align-items: center; justify-content: center; gap: 24px;
}
.borrow-value {
  font-family: var(--font-head); font-size: 48px; font-weight: 800;
  font-variant-numeric: tabular-nums; min-width: 180px; text-align: center;
  letter-spacing: -.02em;
  background: linear-gradient(135deg, var(--text), #b8b9f5);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.borrow-sub {
  font-size: 12px; color: var(--muted); margin-top: 6px;
  font-variant-numeric: tabular-nums;
}
.borrow-btn {
  width: 48px; height: 48px; border-radius: 14px; border: 1px solid var(--border);
  background: var(--bg); color: var(--text); font-size: 26px; font-weight: 600;
  cursor: pointer; display: grid; place-items: center; line-height: 1;
  font-family: var(--font-body);
  transition: all .15s var(--ease);
}
.borrow-btn:hover {
  border-color: var(--accent); color: #fff;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  box-shadow: 0 4px 16px rgba(99,102,241,0.35);
}
.borrow-btn:active { transform: scale(0.92); }

/* ── Trade card ──────────────────────────────────────────── */
.trade-card {
  padding: 20px 22px; margin-bottom: 14px;
  background: linear-gradient(135deg, rgba(99,102,241,0.07), var(--surface));
}
.trade-summary { font-size: 15px; line-height: 1.7; color: #cbd5e1; }
.trade-summary strong { color: var(--text); font-weight: 700; }
.apr-chip {
  display: inline-block; font-size: 12px; font-weight: 700;
  color: var(--gold); background: rgba(251,191,36,0.12);
  padding: 1px 8px; border-radius: 6px; font-variant-numeric: tabular-nums;
}

.trade-legs {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; margin-top: 10px;
}
.leg-card {
  border: 1px solid var(--border); border-radius: 12px;
  padding: 12px 14px; background: var(--bg);
  border-top: 3px solid var(--border);
  transition: transform .15s var(--ease);
}
.leg-card:hover { transform: translateY(-2px); }
.leg-card.buy  { border-top-color: var(--up); }
.leg-card.sell { border-top-color: var(--down); }
.leg-top {
  display: flex; justify-content: space-between; align-items: center;
  margin-bottom: 10px;
}
.leg-action { font-size: 11px; font-weight: 800; letter-spacing: .07em; }
.leg-card.buy  .leg-action { color: var(--up); }
.leg-card.sell .leg-action { color: var(--down); }
.leg-type {
  font-size: 10px; font-weight: 700; padding: 2px 7px;
  border-radius: 6px; letter-spacing: .04em;
}
.leg-type.call { background: rgba(34,211,238,0.14); color: #67e8f9; }
.leg-type.put  { background: rgba(251,191,36,0.14); color: #fcd34d; }
.leg-strike {
  font-family: var(--font-head); font-size: 22px; font-weight: 800;
  font-variant-numeric: tabular-nums;
}
.leg-sub {
  font-family: var(--font-mono); font-size: 11px;
  color: var(--muted); margin-top: 4px;
}

/* ── Grid layouts ────────────────────────────────────────── */
.grid-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 12px; }

/* ── Panels (params) ─────────────────────────────────────── */
.panel { padding: 18px; margin-bottom: 12px; }
.panel-label {
  font-size: 10px; color: var(--muted); font-weight: 700;
  text-transform: uppercase; letter-spacing: .08em; margin-bottom: 12px;
}

.field { display: flex; flex-direction: column; gap: 5px; }
.field label { color: var(--muted); font-size: 12px; font-weight: 600; }

input, select {
  background: var(--bg); color: var(--text); font-family: var(--font-body);
  border: 1px solid var(--border); border-radius: 9px;
  padding: 9px 11px; font-size: 14px; width: 100%;
  transition: border-color .15s var(--ease);
}
input:focus, select:focus { outline: none; border-color: var(--accent); }

.meta-row {
  display: flex; align-items: center; gap: 8px; flex-wrap: wrap;
  margin-top: 14px; font-size: 12px; color: var(--muted);
}

/* ── Stats (KPI cards) ───────────────────────────────────── */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 12px; margin-bottom: 16px;
}
.stat { padding: 16px 18px; transition: border-color .15s var(--ease); }
.stat:hover { border-color: rgba(99,102,241,0.4); }
.stat-label {
  font-size: 11px; color: var(--muted); font-weight: 700;
  text-transform: uppercase; letter-spacing: .05em;
}
.stat-val {
  font-size: 24px; font-weight: 800; font-family: var(--font-head);
  font-variant-numeric: tabular-nums; margin-top: 6px;
}
.stat-hint { font-size: 11px; color: var(--muted); margin-top: 4px; }
.stat-hint a { color: var(--accent); }

/* ── Curve comparison card ───────────────────────────────── */
.curve-card { padding: 18px 20px; margin-bottom: 16px; }
.curve-head {
  display: flex; justify-content: space-between; align-items: baseline;
  gap: 12px; margin-bottom: 12px;
}
.curve-title {
  font-family: var(--font-mono); font-size: 11px; font-weight: 500;
  letter-spacing: var(--brand-credit-tracking, .32em); text-transform: uppercase;
  color: var(--spot-gold);
}
.curve-meta { font-size: 11px; color: var(--muted); }

.bench-row {
  display: grid; grid-template-columns: 80px 1fr 110px;
  gap: 8px; padding: 6px 0; font-size: 13px;
  font-variant-numeric: tabular-nums;
}
.bench-row + .bench-row { border-top: 1px solid rgba(255,255,255,0.04); }
.bench-row.closest { font-weight: 700; }
.bench-row .muted { color: var(--muted); }
.bench-row .pos { color: var(--down); text-align: right; font-size: 12px; }
.bench-row .neg { color: var(--up); text-align: right; font-size: 12px; }

.fair-row {
  margin-top: 14px; padding-top: 14px;
  border-top: 1px solid var(--border);
  display: flex; justify-content: space-between;
  gap: 12px; flex-wrap: wrap; font-size: 13px;
}
.fair-row .muted { color: var(--muted); }
.edge-display { font-size: 12px; color: var(--muted); }

/* ── Verdict banner ──────────────────────────────────────── */
.verdict {
  border-radius: 12px; padding: 14px 18px; font-size: 13px;
  margin-bottom: 16px; line-height: 1.6;
}
.v-info { background: var(--info-bg); color: var(--info-text); }
.v-warn { background: var(--warn-bg); color: var(--warn-text); }
.v-good { background: var(--good-bg); color: var(--good-text); }

/* ── Methodology ─────────────────────────────────────────── */
.methodology {
  padding: 16px 18px; font-size: 13px; color: var(--muted);
}
.methodology summary {
  cursor: pointer; font-weight: 700; color: var(--text);
  font-family: var(--font-head); font-size: 14px;
}
.method-body { margin-top: 12px; line-height: 1.7; }
.method-body p { margin-bottom: 10px; }
.method-body strong { color: var(--text); }
.method-body code {
  background: rgba(255,255,255,0.06); padding: 2px 6px;
  border-radius: 4px; font-family: var(--font-mono); font-size: 12px;
}

/* ── Mobile ──────────────────────────────────────────────── */
@media (max-width: 600px) {
  body { padding: 16px 12px 40px; }
  .hero { flex-direction: column; gap: 10px; }
  .tsy-box { text-align: left; }
  .grid-3 { grid-template-columns: 1fr; }
  .stats { grid-template-columns: 1fr 1fr; }
  .trade-legs { grid-template-columns: 1fr 1fr; }
  .bench-row { grid-template-columns: 60px 1fr 90px; }
  .borrow-value { font-size: 40px; }
}