/* ─────────────────────────────────────────────
   Receipt Vault  ·  Shared page styles
   Monochromatic, system-font, dark-mode-ready
   ───────────────────────────────────────────── */

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

:root {
  --bg:           #0a0a0a;
  --surface:      rgba(255,255,255,0.05);
  --surface-border: rgba(255,255,255,0.08);
  --text-primary: #f0f0f0;
  --text-secondary: #888;
  --text-muted:   #555;
  --accent:       #e0e0e0;
  --accent-dim:   rgba(224,224,224,0.12);
  --radius-card:  18px;
  --radius-pill:  100px;
  --max-w:        680px;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Helvetica, Arial, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg:             #f5f5f7;
    --surface:        rgba(255,255,255,0.75);
    --surface-border: rgba(0,0,0,0.07);
    --text-primary:   #1a1a1a;
    --text-secondary: #555;
    --text-muted:     #999;
    --accent:         #1a1a1a;
    --accent-dim:     rgba(0,0,0,0.06);
  }
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.7;
  background: var(--bg);
  color: var(--text-primary);
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* ── Layout ── */

.page-wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 24px 80px;
}

/* ── Header ── */

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--surface-border);
  position: sticky;
  top: 0;
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  background: rgba(10,10,10,0.7);
  z-index: 100;
}

@media (prefers-color-scheme: light) {
  .site-header { background: rgba(245,245,247,0.75); }
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-primary);
  font-size: 15px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.logo-icon {
  width: 30px;
  height: 30px;
  background: var(--text-primary);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-icon svg { color: var(--bg); }

.nav-links {
  display: flex;
  gap: 20px;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 14px;
  transition: color 0.2s;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] { color: var(--text-primary); }

/* ── Hero ── */

.hero {
  padding: 56px 0 40px;
  border-bottom: 1px solid var(--surface-border);
  margin-bottom: 40px;
}

.tag-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-secondary);
  background: var(--accent-dim);
  border: 1px solid var(--surface-border);
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  margin-bottom: 18px;
}

.hero h1 {
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.hero p {
  font-size: 17px;
  color: var(--text-secondary);
  max-width: 520px;
}

.hero .meta {
  margin-top: 20px;
  font-size: 13px;
  color: var(--text-muted);
}

/* ── Cards ── */

.card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-card);
  padding: 28px 32px;
  margin-bottom: 16px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.card h2 {
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.card h2 .icon {
  width: 28px;
  height: 28px;
  border-radius: 8px;
  background: var(--accent-dim);
  border: 1px solid var(--surface-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 14px;
}

.card p {
  font-size: 15px;
  color: var(--text-secondary);
  margin-bottom: 10px;
}

.card p:last-child { margin-bottom: 0; }

.card ul {
  padding-left: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.card ul li {
  font-size: 15px;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.card ul li::before {
  content: "–";
  color: var(--text-muted);
  flex-shrink: 0;
  margin-top: 1px;
}

/* ── Highlight card ── */

.card-highlight {
  background: var(--accent-dim);
  border-color: rgba(255,255,255,0.12);
}

@media (prefers-color-scheme: light) {
  .card-highlight { border-color: rgba(0,0,0,0.1); }
}

.card-highlight p {
  color: var(--text-primary);
  font-weight: 500;
}

/* ── Section label ── */

.section-label {
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin: 36px 0 12px;
}

/* ── Accordion (FAQ) ── */

details.faq {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-card);
  margin-bottom: 10px;
  overflow: hidden;
}

details.faq summary {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-primary);
  padding: 20px 24px;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  user-select: none;
}

details.faq summary::-webkit-details-marker { display: none; }

details.faq summary::after {
  content: "+";
  font-size: 20px;
  font-weight: 300;
  color: var(--text-muted);
  flex-shrink: 0;
  transition: transform 0.2s;
}

details.faq[open] summary::after {
  transform: rotate(45deg);
}

details.faq .faq-body {
  padding: 0 24px 20px;
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.65;
  border-top: 1px solid var(--surface-border);
  padding-top: 16px;
}

details.faq .faq-body p { margin-bottom: 8px; }
details.faq .faq-body p:last-child { margin-bottom: 0; }

/* ── Contact button ── */

.contact-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 20px;
  padding: 12px 24px;
  background: var(--text-primary);
  color: var(--bg);
  border-radius: var(--radius-pill);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: opacity 0.2s;
}

.contact-btn:hover { opacity: 0.8; }

/* ── Footer ── */

.site-footer {
  border-top: 1px solid var(--surface-border);
  padding: 28px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 13px;
  color: var(--text-muted);
}

.site-footer a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

.site-footer a:hover { color: var(--text-secondary); }

/* ── Responsive ── */

@media (max-width: 480px) {
  .card { padding: 22px 20px; }
  .hero { padding: 36px 0 28px; }
  .nav-links { gap: 14px; }
}