/**
 * FEATOL Lower Back Brace — EMD Authority Microsite
 * Medical Clean • Distinctive typography • Layered depth • Single light source
 */

:root {
  /* Brand — depth variants */
  --brand-primary: #2563eb;
  --brand-primary-hover: #1d4ed8;
  --brand-light: rgba(37, 99, 235, 0.06);
  --brand-border: rgba(37, 99, 235, 0.2);
  --glow-primary: rgba(37, 99, 235, 0.28);

  /* Tinted neutrals (cool slate) — not flat gray */
  --neutral-50: #f8fafc;
  --neutral-100: #f1f5f9;
  --neutral-150: #e2e8f0;
  --neutral-200: #cbd5e1;
  --neutral-300: #94a3b8;
  --neutral-400: #64748b;
  --neutral-500: #475569;
  --neutral-600: #334155;
  --neutral-700: #1e293b;
  --neutral-800: #0f172a;
  --neutral-900: #020617;

  /* Single light source: top-left → shadows bottom-right */
  --shadow-sm: 2px 2px 8px rgba(2, 6, 23, 0.04), 4px 4px 16px rgba(2, 6, 23, 0.02);
  --shadow-md: 4px 4px 16px rgba(2, 6, 23, 0.06), 8px 8px 32px rgba(2, 6, 23, 0.04);
  --shadow-lg: 8px 8px 24px rgba(2, 6, 23, 0.08), 16px 16px 48px rgba(2, 6, 23, 0.04);
  --shadow-brand: 4px 4px 20px var(--glow-primary), 8px 8px 32px rgba(37, 99, 235, 0.12);

  --spacing-unit: 8px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Typography */
  --font-display: "Syne", system-ui, sans-serif;
  --font-body: "Source Serif 4", Georgia, serif;
  --font-technical: "Source Serif 4", Georgia, serif;
}

/* Base */
html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--neutral-800);
  background: var(--neutral-50);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Display headings */
h1, h2, h3, .font-display {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--neutral-900);
}

h1 { letter-spacing: -0.03em; }
h2 { letter-spacing: -0.025em; }

/* Glass panel — refined */
.glass-panel {
  background: linear-gradient(145deg, rgba(255, 255, 255, 0.9) 0%, rgba(248, 250, 252, 0.85) 100%);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.6);
  box-shadow: var(--shadow-md), inset 0 1px 0 rgba(255, 255, 255, 0.8);
  border-radius: var(--radius-xl);
}

/* CTA Amazon — plugin-compatible, premium feel */
.cta-amazon-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  background: var(--brand-primary);
  color: #fff !important;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.9375rem;
  letter-spacing: 0.01em;
  padding: 14px 28px;
  border-radius: var(--radius-md);
  border: none;
  box-shadow: var(--shadow-brand);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
  text-decoration: none;
  cursor: pointer;
}

.cta-amazon-link:hover {
  background: var(--brand-primary-hover);
  box-shadow: 6px 6px 28px var(--glow-primary), 12px 12px 40px rgba(37, 99, 235, 0.15);
  transform: translateY(-2px);
}

.cta-amazon-link:focus {
  outline: 2px solid var(--brand-primary);
  outline-offset: 3px;
}

.cta-glow {
  box-shadow: var(--shadow-brand);
}

.cta-glow:hover {
  box-shadow: 6px 6px 28px var(--glow-primary), 12px 12px 40px rgba(37, 99, 235, 0.15);
}

/* Nav */
.nav-cta-reveal {
  opacity: 0;
  pointer-events: none;
  transform: translateY(-6px);
  transition: opacity 0.35s ease, transform 0.35s ease;
}

.nav-cta-reveal.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

/* Hero badge — refined, not pill-generic */
.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  background: var(--neutral-100);
  border: 1px solid var(--neutral-150);
  border-radius: var(--radius-sm);
  font-family: var(--font-display);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--neutral-600);
  box-shadow: var(--shadow-sm);
}

/* Trust bar — icon blocks with depth */
.trust-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid var(--neutral-150);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.trust-item:hover {
  border-color: var(--neutral-200);
  box-shadow: var(--shadow-md);
}

.trust-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--brand-light);
  border-radius: var(--radius-sm);
  color: var(--brand-primary);
  flex-shrink: 0;
}

/* Bento cards — layered depth, hover lift */
.bento-card {
  background: #fff;
  border: 1px solid var(--neutral-150);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.bento-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--neutral-200);
}

.bento-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(145deg, var(--brand-light) 0%, rgba(37, 99, 235, 0.03) 100%);
  border: 1px solid var(--brand-border);
  border-radius: var(--radius-md);
  color: var(--brand-primary);
}

/* Spec table — editorial feel */
.spec-table-wrap {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--neutral-150);
  box-shadow: var(--shadow-sm);
}

.spec-table-wrap table {
  font-family: var(--font-technical);
}

.spec-table-wrap thead {
  background: var(--neutral-100);
  border-bottom: 1px solid var(--neutral-200);
}

.spec-table-wrap th {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.8125rem;
  letter-spacing: 0.02em;
  text-transform: uppercase;
  color: var(--neutral-600);
}

.spec-table-wrap tbody tr {
  border-bottom: 1px solid var(--neutral-150);
  transition: background 0.15s ease;
}

.spec-table-wrap tbody tr:last-child {
  border-bottom: none;
}

.spec-table-wrap tbody tr:hover {
  background: var(--neutral-50);
}

/* Comparison table — winner column */
.comparison-wrap {
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--neutral-150);
  box-shadow: var(--shadow-md);
}

.comparison-winner {
  background: linear-gradient(135deg, var(--brand-light) 0%, rgba(37, 99, 235, 0.02) 100%);
  border-left: 2px solid var(--brand-primary);
}

.ribbon-best-value {
  position: absolute;
  top: 0;
  right: 0;
  background: var(--brand-primary);
  color: #fff;
  font-family: var(--font-display);
  font-size: 0.6875rem;
  font-weight: 700;
  padding: 6px 14px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-radius: 0 var(--radius-md) 0 8px;
  box-shadow: var(--shadow-sm);
}

/* Price disclaimer */
.price-disclaimer-trigger {
  position: relative;
  cursor: help;
  font-size: 0.8125rem;
  color: var(--neutral-500);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-style: dotted;
}

.price-disclaimer-tooltip {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(-10px);
  background: var(--neutral-800);
  color: var(--neutral-100);
  font-family: var(--font-body);
  font-size: 0.75rem;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  z-index: 20;
  box-shadow: var(--shadow-lg);
}

.price-disclaimer-trigger:hover .price-disclaimer-tooltip,
.price-disclaimer-tooltip.is-visible {
  opacity: 1;
  transform: translateX(-50%) translateY(-6px);
}

/* Section backgrounds — subtle variation */
.section-hero {
  background: linear-gradient(180deg, var(--neutral-50) 0%, #fff 50%, var(--neutral-50) 100%);
}

.section-alt {
  background: linear-gradient(180deg, var(--neutral-50) 0%, var(--neutral-100) 100%);
}

.section-alt .section-inner {
  position: relative;
}

/* Footer */
.footer-dark {
  background: linear-gradient(180deg, var(--neutral-900) 0%, var(--neutral-800) 100%);
  color: var(--neutral-400);
}

.footer-dark a {
  color: var(--neutral-300);
  transition: color 0.2s ease;
}

.footer-dark a:hover {
  color: #fff;
}

.footer-dark h3 {
  font-family: var(--font-display);
  font-size: 0.6875rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--neutral-500);
}

/* Nav header — minimal, confident */
.site-header {
  background: rgba(248, 250, 252, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(203, 213, 225, 0.5);
}

.site-logo {
  font-family: var(--font-display);
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--neutral-900);
}

.nav-forum-link {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.875rem;
  letter-spacing: 0.02em;
  color: var(--neutral-600);
  padding: 8px 16px;
  border: 1px solid var(--neutral-200);
  border-radius: var(--radius-md);
  background: #fff;
  text-decoration: none;
  box-shadow: 0 1px 2px rgba(2, 6, 23, 0.04);
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.nav-forum-link:hover {
  color: var(--brand-primary);
  border-color: var(--brand-primary);
  background: rgba(37, 99, 235, 0.06);
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.12);
}

.nav-forum-link:focus {
  outline: 2px solid var(--brand-primary);
  outline-offset: 2px;
}

/* Testimonial cards */
.testimonial-card {
  background: #fff;
  border: 1px solid var(--neutral-150);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.testimonial-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--neutral-200);
}

.testimonial-star {
  color: #eab308;
  font-size: 1rem;
}

/* FAQ accordion */
.faq-list {
  --faq-shadow: var(--shadow-sm);
}

.faq-item {
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.faq-item:hover {
  box-shadow: var(--shadow-md);
}

.faq-item.is-open {
  border-color: var(--neutral-200);
  box-shadow: var(--shadow-md);
}

.faq-trigger {
  cursor: pointer;
  border: none;
  background: none;
  font-size: 0.9375rem;
}

.faq-trigger:focus {
  outline: 2px solid var(--brand-primary);
  outline-offset: 2px;
}

.faq-trigger:focus:not(:focus-visible) {
  outline: none;
}

.faq-panel {
  transition: opacity 0.2s ease;
}

.faq-panel.is-open .faq-chevron {
  transform: rotate(180deg);
}

.faq-item .faq-chevron {
  transform: rotate(0deg);
}

.faq-item.is-open .faq-chevron {
  transform: rotate(180deg);
}

/* Decorative — very subtle hero accent */
.hero-accent {
  position: absolute;
  width: 60%;
  height: 80%;
  top: 10%;
  right: -10%;
  background: radial-gradient(ellipse at 70% 50%, var(--brand-light) 0%, transparent 70%);
  pointer-events: none;
}

/* Subtle depth — hero section feels less flat */
.section-hero {
  position: relative;
}