/* Stack Calculator — Stylesheet */
/* Mirrors the loans.css design system */

:root {
  --bg: #FAFAF7;
  --bg-warm: #F5F3EE;
  --card: #FFFFFF;
  --text: #1C1917;
  --text-secondary: #57534E;
  --muted: #A8A29E;
  --accent: #E8740C;
  --accent-hover: #D16A0B;
  --accent-soft: rgba(232, 116, 12, 0.08);
  --accent-softer: rgba(232, 116, 12, 0.04);
  --green: #15803D;
  --green-soft: rgba(21, 128, 61, 0.08);
  --green-text: #166534;
  --green-border: rgba(21, 128, 61, 0.18);
  --red: #B91C1C;
  --red-soft: rgba(185, 28, 28, 0.06);
  --amber: #B45309;
  --amber-soft: rgba(180, 83, 9, 0.08);
  --border: #E7E5E4;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
  --radius: 16px;
  --radius-sm: 10px;
}

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

body {
  font-family: 'DM Sans', system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* === NAV === */
nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 32px;
  background: rgba(250, 250, 247, 0.88);
  backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}
.logo { display: flex; align-items: center; gap: 10px; text-decoration: none; color: var(--text); }
.logo-mark {
  width: 32px; height: 32px; background: var(--accent); border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  color: white; font-weight: 700; font-size: 16px;
}
.logo-text { font-family: 'Source Serif 4', Georgia, serif; font-weight: 700; font-size: 17px; letter-spacing: -0.02em; }
.nav-right { display: flex; align-items: center; gap: 16px; font-size: 13px; color: var(--muted); }
.btc-price {
  display: flex; align-items: center; gap: 6px;
  font-family: 'JetBrains Mono', monospace; font-size: 12px; color: var(--text-secondary);
  background: var(--bg-warm); padding: 5px 12px; border-radius: 100px; border: 1px solid var(--border);
}
.btc-price .dot { width: 6px; height: 6px; background: var(--green); border-radius: 50%; animation: pulse 2s infinite; }
@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.4; } }

/* === NAV LINK === */
.nav-link {
  font-size: 13px; font-weight: 600; color: var(--accent);
  text-decoration: none; padding: 5px 14px; border-radius: 100px;
  border: 1px solid rgba(232, 116, 12, 0.2); transition: all 0.15s;
}
.nav-link:hover { background: var(--accent-soft); border-color: var(--accent); }

/* === LAYOUT === */
.page { max-width: 860px; margin: 0 auto; padding: 0 24px; }

/* === HERO === */
.hero { text-align: center; padding: 52px 0 36px; }
.hero h1 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 42px; font-weight: 700; letter-spacing: -0.03em; line-height: 1.15; margin-bottom: 10px;
}
.hero h1 em { font-style: normal; color: var(--accent); }
.hero p { font-size: 17px; color: var(--text-secondary); max-width: 480px; margin: 0 auto; }
.disclaimer {
  display: inline-block; font-size: 11px; color: var(--muted);
  background: var(--bg-warm); border: 1px solid var(--border);
  padding: 3px 12px; border-radius: 100px; margin-top: 14px;
}

/* === INPUT BAR === */
.input-bar {
  display: flex; gap: 12px; flex-wrap: wrap;
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px 28px; box-shadow: var(--shadow-md); margin-bottom: 40px;
}
.input-group { flex: 1; min-width: 130px; }
.input-group label {
  display: block; font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); margin-bottom: 5px;
}
.input-group input, .input-group select {
  width: 100%; height: 40px; padding: 0 12px;
  border: 1px solid var(--border); border-radius: 8px;
  font-family: 'JetBrains Mono', monospace; font-size: 14px; font-weight: 500;
  color: var(--text); background: var(--bg); outline: none; transition: border-color 0.15s;
}
.input-group input:focus, .input-group select:focus {
  border-color: var(--accent); box-shadow: 0 0 0 3px rgba(232, 116, 12, 0.08);
}
.input-prefix {
  display: flex; align-items: center; height: 40px;
  border: 1px solid var(--border); border-radius: 8px; background: var(--bg);
  overflow: hidden; transition: border-color 0.15s;
}
.input-prefix:focus-within { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(232, 116, 12, 0.08); }
.input-prefix span {
  padding: 8px 0 8px 12px; font-family: 'JetBrains Mono', monospace;
  font-size: 14px; color: var(--muted); user-select: none;
}
.input-prefix input {
  border: none; background: transparent; padding-left: 4px; flex: 1; min-width: 0; height: 100%;
}
.input-prefix input:focus { border-color: transparent; box-shadow: none; }

/* === RECOMMENDATION BANNER === */
.reco-banner {
  display: flex; align-items: center; gap: 16px;
  border-radius: var(--radius); padding: 18px 24px;
  margin-bottom: 8px; transition: all 0.3s ease;
}
.reco-banner[data-zone="deep-discount"] {
  background: var(--green-soft); border: 1px solid var(--green-border);
}
.reco-banner[data-zone="discount"] {
  background: var(--green-soft); border: 1px solid var(--green-border);
}
.reco-banner[data-zone="fair"] {
  background: var(--bg-warm); border: 1px solid var(--border);
}
.reco-banner[data-zone="premium"] {
  background: var(--accent-softer); border: 1px solid rgba(232, 116, 12, 0.15);
}
.reco-banner[data-zone="high-premium"] {
  background: var(--red-soft); border: 1px solid rgba(185, 28, 28, 0.15);
}
.reco-icon {
  width: 40px; height: 40px; border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-size: 18px; font-weight: 700; flex-shrink: 0; color: white;
}
.reco-banner[data-zone="deep-discount"] .reco-icon { background: var(--green); }
.reco-banner[data-zone="discount"] .reco-icon { background: var(--green); }
.reco-banner[data-zone="fair"] .reco-icon { background: var(--text-secondary); }
.reco-banner[data-zone="premium"] .reco-icon { background: var(--accent); }
.reco-banner[data-zone="high-premium"] .reco-icon { background: var(--red); }
.reco-body { flex: 1; }
.reco-headline {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 16px; font-weight: 700; letter-spacing: -0.01em; color: var(--text);
}
.reco-detail { font-size: 13px; color: var(--text-secondary); margin-top: 2px; line-height: 1.5; }
.reco-tag {
  flex-shrink: 0; font-family: 'JetBrains Mono', monospace;
  font-size: 12px; font-weight: 600; padding: 4px 12px; border-radius: 6px;
  white-space: nowrap;
}
.reco-banner[data-zone="deep-discount"] .reco-tag { background: var(--green-soft); color: var(--green-text); }
.reco-banner[data-zone="discount"] .reco-tag { background: var(--green-soft); color: var(--green-text); }
.reco-banner[data-zone="fair"] .reco-tag { background: var(--bg); color: var(--text-secondary); }
.reco-banner[data-zone="premium"] .reco-tag { background: var(--accent-soft); color: var(--accent); }
.reco-banner[data-zone="high-premium"] .reco-tag { background: var(--red-soft); color: var(--red); }

/* === HISTOGRAM CARD === */
.hist-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px 24px 16px; margin-bottom: 8px; box-shadow: var(--shadow-sm);
}
.hist-stat {
  font-size: 14px; color: var(--text-secondary); margin-bottom: 12px; text-align: center;
}
.hist-stat strong { color: var(--text); font-weight: 700; }
.hist-svg { margin: 0 -8px; }
.hist-caption {
  font-size: 11px; color: var(--muted); line-height: 1.5; margin-top: 8px; text-align: center;
}
.hist-caption strong { color: var(--text-secondary); font-weight: 600; }

@media (max-width: 768px) {
  .reco-banner { flex-wrap: wrap; }
  .reco-tag { width: 100%; text-align: center; margin-top: 4px; }
  .hist-card { padding: 16px 12px 12px; }
}

/* === STEPS / SECTIONS === */
.step {
  display: flex; align-items: center; gap: 14px;
  margin: 48px 0 8px;
}
.step-number {
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--text); color: var(--card);
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 16px; flex-shrink: 0;
}
.step h2 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 24px; font-weight: 700; letter-spacing: -0.02em;
}
.step-subtitle {
  font-size: 15px; color: var(--text-secondary);
  margin: 4px 0 20px 50px;
}

/* === BIG HERO CARD === */
.big-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 32px 36px; text-align: center; position: relative; overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.big-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: var(--accent);
}
.big-label {
  font-size: 11px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.06em; color: var(--muted); margin-bottom: 8px;
}
.big-number {
  font-family: 'JetBrains Mono', monospace; font-size: 48px; font-weight: 700;
  letter-spacing: -0.04em; line-height: 1; color: var(--accent);
}
.big-btc {
  font-family: 'JetBrains Mono', monospace; font-size: 18px;
  color: var(--text); margin-top: 8px; font-weight: 600;
}
.big-invested { font-size: 14px; color: var(--text-secondary); margin-top: 4px; }
.big-meta {
  display: flex; justify-content: center; gap: 40px;
  margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--border);
}
.meta-item { text-align: center; }
.meta-label {
  font-size: 10px; color: var(--muted); text-transform: uppercase; letter-spacing: 0.05em;
}
.meta-value {
  font-family: 'JetBrains Mono', monospace; font-size: 17px; font-weight: 600; margin-top: 2px;
}

/* === CORRIDOR CARD === */
.corridor-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px 28px; box-shadow: var(--shadow-sm);
}
.corridor-row {
  display: flex; align-items: center; gap: 16px;
  padding: 12px 0; border-bottom: 1px solid var(--border);
}
.corridor-row:last-of-type { border-bottom: none; }
.corridor-label {
  font-size: 13px; color: var(--text-secondary); width: 100px; flex-shrink: 0;
}
.corridor-value {
  font-family: 'JetBrains Mono', monospace; font-size: 22px; font-weight: 700;
  letter-spacing: -0.03em; flex: 1;
}
.corridor-row.ceiling .corridor-value { color: var(--muted); }
.corridor-row.trend .corridor-value { color: var(--accent); }
.corridor-row.floor .corridor-value { color: var(--green); }
.corridor-tag {
  font-size: 11px; font-weight: 600; padding: 3px 10px; border-radius: 6px;
}
.corridor-row.ceiling .corridor-tag { background: rgba(168,162,158,0.1); color: var(--muted); }
.corridor-row.trend .corridor-tag { background: var(--accent-soft); color: var(--accent); }
.corridor-row.floor .corridor-tag { background: var(--green-soft); color: var(--green); }
.corridor-visual { padding: 20px 0 12px; }
.corridor-bar {
  height: 12px;
  background: linear-gradient(90deg, var(--green-soft), var(--accent-soft), rgba(168,162,158,0.1));
  border-radius: 6px; position: relative;
}
.corridor-note {
  font-size: 13px; color: var(--text-secondary); margin-top: 8px; line-height: 1.6;
}
.corridor-note strong { color: var(--text); }
.corridor-note .green {
  color: var(--green); font-weight: 700; font-family: 'JetBrains Mono', monospace;
}

/* === COMPARE CARD (BTC vs S&P) === */
.compare-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px 32px; box-shadow: var(--shadow-sm);
}
.compare-row {
  display: flex; align-items: stretch; gap: 0;
}
.compare-side {
  flex: 1; text-align: center; padding: 20px 16px;
}
.compare-side.btc-side {
  background: var(--accent-soft); border-radius: 12px 0 0 12px;
}
.compare-side.spx-side {
  background: var(--bg-warm); border-radius: 0 12px 12px 0;
}
.compare-vs {
  display: flex; align-items: center; justify-content: center;
  font-size: 14px; font-weight: 700; color: var(--muted); padding: 0 16px;
  background: var(--card);
}
.compare-icon { font-size: 28px; margin-bottom: 6px; }
.compare-asset {
  font-size: 12px; font-weight: 600; text-transform: uppercase;
  letter-spacing: 0.05em; color: var(--text-secondary); margin-bottom: 8px;
}
.compare-amount {
  font-family: 'JetBrains Mono', monospace; font-size: 26px; font-weight: 700;
  letter-spacing: -0.03em; color: var(--text);
}
.compare-return { font-size: 13px; color: var(--text-secondary); margin-top: 4px; }
.compare-diff {
  text-align: center; margin-top: 16px; padding: 12px 16px; border-radius: 10px;
  background: var(--accent-soft); font-size: 14px; font-weight: 600; color: var(--accent);
}
.compare-note {
  margin-top: 16px; font-size: 12px; color: var(--muted); line-height: 1.6;
}
.compare-note strong { color: var(--text-secondary); }

/* === YEARLY TABLE === */
.result-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px 28px; margin-top: 28px; box-shadow: var(--shadow-sm);
}
.card-label {
  font-family: 'Source Serif 4', Georgia, serif; font-size: 17px; font-weight: 700;
  letter-spacing: -0.02em;
}
.card-subtitle {
  font-size: 13px; color: var(--text-secondary); margin-top: 2px; margin-bottom: 16px;
}
.monitor-table { width: 100%; border-collapse: collapse; font-size: 13px; }
.monitor-table th {
  text-align: left; padding: 8px 12px; font-size: 10px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted);
  border-bottom: 2px solid var(--border);
}
.monitor-table td {
  padding: 8px 12px; border-bottom: 1px solid var(--border);
  font-family: 'JetBrains Mono', monospace; font-size: 12px;
}
.monitor-table tr:last-child td { border-bottom: none; font-weight: 700; }

/* === NARRATIVE === */
.narrative {
  border-radius: 14px; padding: 20px 24px; margin-top: 28px;
  background: var(--bg-warm); border: 1px solid var(--border);
}
.narrative-label {
  font-size: 11px; font-weight: 700; text-transform: uppercase;
  letter-spacing: 0.08em; margin-bottom: 6px; color: var(--text-secondary);
}
.narrative p { font-size: 14px; line-height: 1.7; color: var(--text-secondary); }
.narrative strong { color: var(--text); }

/* === BRIDGE CARD === */
.bridge-card {
  display: flex; align-items: center; gap: 16px;
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px 24px; margin-top: 24px; box-shadow: var(--shadow-sm);
}
.bridge-icon { flex-shrink: 0; color: var(--text-secondary); }
.bridge-text { flex: 1; font-size: 14px; color: var(--text-secondary); line-height: 1.5; }
.bridge-text strong { color: var(--text); }
.bridge-btn {
  flex-shrink: 0; font-size: 13px; font-weight: 600; color: var(--accent);
  text-decoration: none; padding: 8px 18px; border-radius: 100px;
  border: 1px solid rgba(232, 116, 12, 0.25); white-space: nowrap; transition: all 0.15s;
}
.bridge-btn:hover { background: var(--accent-soft); border-color: var(--accent); }

/* === CTA === */
.cta-card {
  background: var(--card); border: 2px solid var(--accent); border-radius: var(--radius);
  padding: 36px; text-align: center; margin-top: 48px;
  box-shadow: 0 4px 20px rgba(232, 116, 12, 0.08);
}
.cta-card h3 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 22px; font-weight: 700; letter-spacing: -0.02em; margin-bottom: 8px;
}
.cta-card p { font-size: 14px; color: var(--text-secondary); max-width: 420px; margin: 0 auto 24px; line-height: 1.55; }
.cta-btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px; background: var(--accent); color: white; border: none;
  border-radius: 100px; font-size: 15px; font-weight: 600;
  cursor: pointer; font-family: inherit; transition: all 0.2s; text-decoration: none;
}
.cta-btn:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(232, 116, 12, 0.25); }
.cta-details { display: flex; justify-content: center; gap: 24px; margin-top: 16px; font-size: 12px; color: var(--muted); }
.cta-details span { display: flex; align-items: center; gap: 4px; }

/* === FOOTER === */
footer {
  padding: 32px 24px; text-align: center; font-size: 11px;
  color: var(--muted); line-height: 1.8;
  border-top: 1px solid var(--border); margin-top: 48px;
}

/* === RESPONSIVE === */
@media (max-width: 768px) {
  .hero h1 { font-size: 32px; }
  nav { padding: 12px 16px; flex-wrap: wrap; justify-content: center; gap: 8px; }
  .logo { width: 100%; justify-content: center; }
  .nav-right { width: 100%; justify-content: center; }
  .page { padding: 0 16px; }
  .input-bar { flex-direction: column; }
  .big-number { font-size: 32px; }
  .big-meta { flex-direction: column; gap: 14px; }
  .corridor-row { flex-direction: column; gap: 4px; align-items: flex-start; }
  .corridor-value { font-size: 18px; }
  .compare-row { flex-direction: column; }
  .compare-side.btc-side { border-radius: 12px 12px 0 0; }
  .compare-side.spx-side { border-radius: 0 0 12px 12px; }
  .compare-vs { padding: 8px 0; }
  .compare-amount { font-size: 20px; }
  .step-subtitle { padding-left: 0; }
  .step h2 { font-size: 20px; }
  .bridge-card { flex-direction: column; text-align: center; }
  .bridge-btn { width: 100%; text-align: center; }
}