/* Calcohol — web styles */

:root {
  --bg: #121225;
  --surface: #1e1e38;
  --surface-elevated: #2e2e52;
  --border: rgba(255, 255, 255, 0.08);
  --text: #f4f4f8;
  --text-secondary: rgba(244, 244, 248, 0.62);
  --text-tertiary: rgba(244, 244, 248, 0.38);
  --accent: #f5b54a;
  --accent-soft: rgba(245, 181, 74, 0.14);
  --accent-gradient-start: #fad661;
  --bac-safe: #4ade80;
  --bac-moderate: #e8a838;
  --bac-high: #f87171;
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 28px;
  --shadow: 0 24px 64px rgba(0, 0, 0, 0.45);
  --max-width: 1080px;
  --nav-height: 64px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow-x: clip;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: opacity 0.2s ease;
}

a:hover {
  opacity: 0.85;
}

.container {
  width: min(100% - 40px, var(--max-width));
  margin-inline: auto;
}

/* Navigation */

.nav {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  height: var(--nav-height);
  backdrop-filter: blur(18px);
  background: rgba(18, 18, 37, 0.78);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text);
  font-weight: 600;
  letter-spacing: -0.02em;
}

.brand img {
  width: 28px;
  height: 28px;
  border-radius: 7px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--text);
  opacity: 1;
}

/* Hero */

.hero {
  position: relative;
  padding: calc(var(--nav-height) + 72px) 0 96px;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 70% 50% at 50% -10%, rgba(245, 181, 74, 0.12), transparent),
    linear-gradient(180deg, rgba(30, 30, 56, 0.55) 0%, var(--bg) 55%);
  pointer-events: none;
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 20px;
}

.hero h1 {
  margin: 0 0 18px;
  font-size: clamp(2.4rem, 5vw, 3.6rem);
  font-weight: 700;
  line-height: 1.08;
  letter-spacing: -0.03em;
}

.hero h1 span {
  background: linear-gradient(135deg, var(--accent-gradient-start), var(--accent));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.hero-lead {
  margin: 0 0 32px;
  max-width: 520px;
  font-size: 1.125rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 22px;
  border-radius: 14px;
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.btn:hover {
  transform: translateY(-1px);
  opacity: 1;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-gradient-start), var(--accent));
  color: #1a1208;
  box-shadow: 0 8px 28px rgba(245, 181, 74, 0.28);
}

.btn-secondary {
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--border);
}

.hero-visual {
  position: relative;
}

.phone-card {
  background: linear-gradient(160deg, var(--surface-elevated), var(--surface));
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  box-shadow: var(--shadow);
}

.phone-card-label {
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: 8px;
}

.bac-display {
  font-family: ui-rounded, "SF Pro Rounded", "Inter", sans-serif;
  font-size: 4rem;
  font-weight: 200;
  font-variant-numeric: tabular-nums;
  line-height: 1;
  margin-bottom: 6px;
  color: var(--bac-moderate);
}

.bac-caption {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 24px;
}

.chart-preview {
  height: 140px;
  border-radius: var(--radius-sm);
  background: rgba(0, 0, 0, 0.22);
  border: 1px solid var(--border);
  overflow: hidden;
  position: relative;
}

.chart-preview svg {
  width: 100%;
  height: 100%;
}

.bac-legend {
  display: flex;
  gap: 16px;
  margin-top: 18px;
  flex-wrap: wrap;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 7px;
  font-size: 0.78rem;
  color: var(--text-secondary);
}

.legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

/* Difference / comparison */

.difference {
  padding-top: 0;
}

.compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 32px;
}

.compare-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
}

.compare-calcohol {
  border-color: rgba(245, 181, 74, 0.3);
  background: linear-gradient(160deg, rgba(245, 181, 74, 0.06), var(--surface));
}

.compare-label {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  margin-bottom: 12px;
}

.compare-calcohol .compare-label {
  color: var(--accent);
}

.compare-card h3 {
  margin: 0 0 16px;
  font-size: 1.15rem;
}

.compare-card ul {
  margin: 0 0 20px;
  padding-left: 18px;
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.compare-card li {
  margin-bottom: 8px;
}

.compare-card li::marker {
  color: var(--text-tertiary);
}

.compare-calcohol li::marker {
  color: var(--accent);
}

.compare-result {
  padding: 12px 16px;
  border-radius: 10px;
  font-family: ui-rounded, "SF Pro Rounded", "Inter", sans-serif;
  font-size: 0.88rem;
  font-variant-numeric: tabular-nums;
  font-weight: 500;
}

.compare-result.muted {
  background: rgba(0, 0, 0, 0.25);
  color: var(--text-tertiary);
}

.compare-result.accent {
  background: var(--accent-soft);
  color: var(--accent);
}

.difference-note {
  margin: 0;
  padding: 24px 28px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 1.02rem;
  line-height: 1.75;
}

/* Sections */

section {
  padding: 88px 0;
}

.section-header {
  max-width: 640px;
  margin-bottom: 48px;
}

.section-label {
  display: inline-block;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.section-header h2 {
  margin: 0 0 14px;
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.section-header p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 1.05rem;
}

/* Feature cards */

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.feature-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.feature-card:hover {
  border-color: rgba(245, 181, 74, 0.25);
  transform: translateY(-2px);
}

.feature-icon {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 1.25rem;
  margin-bottom: 18px;
}

.feature-card h3 {
  margin: 0 0 10px;
  font-size: 1.1rem;
}

.feature-card p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* Science / methodology */

.science {
  background:
    radial-gradient(ellipse 60% 40% at 80% 20%, rgba(74, 222, 128, 0.04), transparent),
    radial-gradient(ellipse 50% 35% at 10% 80%, rgba(245, 181, 74, 0.05), transparent);
}

.methodology-grid {
  display: grid;
  gap: 24px;
  min-width: 0;
}

.method-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 32px;
  min-width: 0;
  max-width: 100%;
}

.method-card h3 {
  margin: 0 0 8px;
  font-size: 1.25rem;
  line-height: 1.35;
  overflow-wrap: anywhere;
}

.method-card .method-intro {
  margin: 0 0 20px;
  color: var(--text-secondary);
  overflow-wrap: anywhere;
}

.formula-block {
  background: rgba(0, 0, 0, 0.28);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 20px 24px;
  margin: 16px 0;
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.formula-block .katex-display {
  margin: 0;
  overflow-x: auto;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
}

.formula-block .katex {
  font-size: clamp(0.88rem, 2.8vw, 1.05rem);
}

.table-wrap {
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 16px 0;
}

.constants-table {
  width: 100%;
  min-width: 0;
  border-collapse: collapse;
  font-size: 0.92rem;
}

.constants-table th,
.constants-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.constants-table th {
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.constants-table td:first-child {
  font-family: ui-monospace, "SF Mono", monospace;
  color: var(--accent);
}

.constants-table tr:last-child td {
  border-bottom: none;
}

.method-list {
  margin: 12px 0 0;
  padding-left: 20px;
  color: var(--text-secondary);
}

.method-list li {
  margin-bottom: 8px;
}

.method-list li::marker {
  color: var(--accent);
}

.citation {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 4px;
  margin-top: 16px;
  padding: 10px 14px;
  border-radius: 10px;
  background: var(--accent-soft);
  font-size: 0.85rem;
  color: var(--text-secondary);
  max-width: 100%;
  overflow-wrap: anywhere;
}

.citation a {
  font-weight: 500;
}

.flow-diagram {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
  margin: 24px 0;
}

.flow-step {
  background: rgba(0, 0, 0, 0.22);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 18px 14px;
  text-align: center;
}

.flow-step-num {
  display: inline-grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 10px;
}

.flow-step h4 {
  margin: 0 0 6px;
  font-size: 0.88rem;
}

.flow-step p {
  margin: 0;
  font-size: 0.78rem;
  color: var(--text-secondary);
  line-height: 1.45;
}

/* References */

.references-list {
  display: grid;
  gap: 14px;
}

.reference-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  padding: 20px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}

.ref-num {
  font-weight: 700;
  color: var(--accent);
  font-size: 0.9rem;
}

.reference-item p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.reference-item strong {
  color: var(--text);
  display: block;
  margin-bottom: 4px;
}

/* Disclaimer */

.disclaimer {
  padding-bottom: 48px;
}

.disclaimer-box {
  background: linear-gradient(135deg, rgba(232, 168, 56, 0.08), rgba(248, 113, 113, 0.06));
  border: 1px solid rgba(232, 168, 56, 0.22);
  border-radius: var(--radius-md);
  padding: 32px;
}

.disclaimer-box h2 {
  margin: 0 0 16px;
  font-size: 1.3rem;
  display: flex;
  align-items: center;
  gap: 10px;
}

.disclaimer-box ul {
  margin: 0;
  padding-left: 20px;
  color: var(--text-secondary);
}

.disclaimer-box li {
  margin-bottom: 10px;
}

.disclaimer-box li::marker {
  color: var(--bac-moderate);
}

/* Footer */

.footer {
  border-top: 1px solid var(--border);
  padding: 32px 0 48px;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  color: var(--text-tertiary);
  font-size: 0.85rem;
}

.footer-links {
  display: flex;
  align-items: center;
  gap: 20px;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
}

/* Subpages — privacy, FAQ */

.page-hero {
  padding: calc(var(--nav-height) + 56px) 0 40px;
}

.page-hero h1 {
  margin: 0 0 14px;
  font-size: clamp(2rem, 4vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.page-lead {
  margin: 0;
  max-width: 640px;
  color: var(--text-secondary);
  font-size: 1.08rem;
  line-height: 1.7;
}

.page-meta {
  margin: 16px 0 0;
  color: var(--text-tertiary);
  font-size: 0.88rem;
}

.legal-content {
  padding: 0 0 88px;
}

.legal-grid,
.faq-grid {
  display: grid;
  gap: 20px;
}

.legal-card,
.support-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 28px 32px;
}

.legal-card h2,
.faq-group h2 {
  margin: 0 0 14px;
  font-size: 1.2rem;
}

.legal-card p,
.support-card p {
  margin: 0 0 14px;
  color: var(--text-secondary);
}

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

.legal-list {
  margin: 0;
  padding-left: 20px;
  color: var(--text-secondary);
}

.legal-list li {
  margin-bottom: 10px;
}

.legal-list li::marker {
  color: var(--accent);
}

.faq-section {
  padding: 0 0 88px;
}

.faq-group {
  display: grid;
  gap: 12px;
}

.faq-item {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0 22px;
}

.faq-item summary {
  cursor: pointer;
  padding: 18px 0;
  font-weight: 600;
  list-style: none;
}

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

.faq-item summary::after {
  content: "+";
  float: right;
  color: var(--accent);
  font-weight: 700;
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item p {
  margin: 0 0 18px;
  color: var(--text-secondary);
  line-height: 1.65;
}

/* Responsive */

@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 40px;
  }

  .hero-visual {
    max-width: 420px;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .compare-grid {
    grid-template-columns: 1fr;
  }

  .flow-diagram {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .nav-links {
    display: none;
  }

  .container {
    width: min(100% - 32px, var(--max-width));
  }

  section {
    padding: 64px 0;
  }

  .section-header {
    margin-bottom: 32px;
  }

  .flow-diagram {
    grid-template-columns: 1fr;
  }

  .method-card {
    padding: 20px 16px;
  }

  .method-card h3 {
    font-size: 1.05rem;
  }

  .method-card .method-intro,
  .method-list {
    font-size: 0.92rem;
  }

  .formula-block {
    padding: 14px 12px;
    margin: 12px 0;
  }

  .table-wrap {
    overflow-x: visible;
    margin: 12px 0;
  }

  .constants-table {
    font-size: 0.88rem;
  }

  .constants-table thead {
    display: none;
  }

  .constants-table tbody,
  .constants-table tr,
  .constants-table td {
    display: block;
  }

  .constants-table tr {
    margin-bottom: 10px;
    padding: 12px 14px;
    background: rgba(0, 0, 0, 0.18);
    border: 1px solid var(--border);
    border-radius: 10px;
  }

  .constants-table tr:last-child {
    margin-bottom: 0;
  }

  .constants-table td {
    display: grid;
    grid-template-columns: minmax(72px, 34%) 1fr;
    gap: 8px 12px;
    padding: 5px 0;
    border-bottom: none;
    text-align: left;
  }

  .constants-table td::before {
    content: attr(data-label);
    font-family: "Inter", sans-serif;
    font-size: 0.68rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--text-secondary);
  }

  .constants-table td:first-child {
    font-family: "Inter", sans-serif;
    color: var(--text);
    font-weight: 600;
    font-size: 0.92rem;
    grid-template-columns: 1fr;
  }

  .constants-table td:first-child::before {
    content: none;
  }

  .citation {
    font-size: 0.82rem;
    padding: 10px 12px;
  }

  .difference-note {
    padding: 18px 16px;
    font-size: 0.95rem;
  }
}