/* ==========================================================================
   Main Stylesheet: Reverent Photography & Minimal UI
   Strictly aligned with Apple Web Design Language (design.md)
   ========================================================================== */

@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/variable/pretendardvariable.css');
@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500&display=swap');

/* Reset & Base Setup */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-family: var(--font-text);
  background-color: var(--colors-canvas);
  color: var(--colors-ink);
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--total-nav-height) + 16px);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  line-height: 1.47;
  font-size: 17px; /* typography.body: Apple runs paragraph at 17px, not 16px */
  font-weight: var(--weight-regular); /* 400 */
  letter-spacing: -0.374px;
  color: var(--colors-ink);
  background-color: var(--colors-canvas);
  overflow-x: hidden;
}

/* Typography Hierarchy (Apple tight display tracking) */
.hero-display {
  font-family: var(--font-display);
  font-size: clamp(38px, 5.5vw, 56px);
  font-weight: var(--weight-semibold); /* 600 */
  line-height: 1.07;
  letter-spacing: -0.28px;
}

.display-lg {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 40px);
  font-weight: var(--weight-semibold);
  line-height: 1.10;
  letter-spacing: 0;
}

.display-md {
  font-family: var(--font-display);
  font-size: clamp(24px, 3.2vw, 34px);
  font-weight: var(--weight-semibold);
  line-height: 1.47;
  letter-spacing: -0.374px;
}

.lead {
  font-size: clamp(20px, 2.5vw, 28px);
  font-weight: var(--weight-regular); /* 400 */
  line-height: 1.14;
  letter-spacing: 0.196px;
  color: var(--colors-ink);
}

.lead-on-dark {
  color: var(--colors-body-muted);
}

.tagline {
  font-size: 21px;
  font-weight: var(--weight-semibold);
  line-height: 1.19;
  letter-spacing: 0.231px;
}

.body-strong {
  font-size: 17px;
  font-weight: var(--weight-semibold);
  line-height: 1.24;
  letter-spacing: -0.374px;
}

.caption-apple {
  font-size: 14px;
  font-weight: var(--weight-regular);
  line-height: 1.43;
  letter-spacing: -0.224px;
  color: var(--colors-ink-muted-48);
}

/* Links */
a.text-link {
  color: var(--colors-primary); /* Action Blue #0066cc */
  text-decoration: none;
  font-size: 17px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

a.text-link:hover {
  text-decoration: underline;
}

a.text-link-on-dark {
  color: var(--colors-primary-on-dark); /* Sky Link Blue #2997ff */
  text-decoration: none;
  font-size: 17px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

a.text-link-on-dark:hover {
  text-decoration: underline;
}

/* Container */
.container {
  width: 100%;
  max-width: 1024px;
  margin-inline: auto;
  padding-inline: var(--spacing-lg);
}

.container-wide {
  width: 100%;
  max-width: 1280px;
  margin-inline: auto;
  padding-inline: var(--spacing-lg);
}

/* ==========================================================================
   Navigation: Two-Row Nav (Global Nav + Frosted Sub-Nav)
   ========================================================================== */

/* 1. Global Nav (Pure Black 44px) */
.global-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--global-nav-height);
  background-color: var(--colors-surface-black);
  z-index: 1000;
  display: flex;
  align-items: center;
}

.global-nav .container-wide {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.global-nav-brand {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #ffffff;
  font-size: 14px;
  font-weight: var(--weight-semibold);
  text-decoration: none;
}

.global-nav-links {
  display: flex;
  align-items: center;
  gap: 24px;
  list-style: none;
}

.global-nav-link {
  color: #d6d6d6;
  font-size: 12px;
  font-weight: var(--weight-regular);
  letter-spacing: -0.12px;
  text-decoration: none;
  transition: color var(--transition-fast);
}

.global-nav-link:hover {
  color: #ffffff;
}

/* 2. Sub-Nav (Frosted Glass 52px, Sticky below Global Nav) */
.sub-nav-frosted {
  position: fixed;
  top: var(--global-nav-height);
  left: 0;
  right: 0;
  height: var(--sub-nav-height);
  background-color: rgba(245, 245, 247, 0.8);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--colors-divider-soft);
  z-index: 999;
  display: flex;
  align-items: center;
}

.sub-nav-frosted .container-wide {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.sub-nav-category {
  font-size: 21px;
  font-weight: var(--weight-semibold);
  line-height: 1.19;
  letter-spacing: 0.231px;
  color: var(--colors-ink);
  text-decoration: none;
}

.sub-nav-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.sub-nav-menu {
  display: flex;
  align-items: center;
  gap: 16px;
  list-style: none;
}

.sub-nav-link {
  font-size: 14px;
  font-weight: var(--weight-regular);
  letter-spacing: -0.224px;
  color: var(--colors-ink-muted-80);
  text-decoration: none;
}

.sub-nav-link:hover {
  color: var(--colors-primary);
}

/* ==========================================================================
   Full-Bleed Alternating Tiles: Light ↔ Dark ↔ Parchment (No Borders)
   ========================================================================== */

.product-tile {
  padding-block: var(--spacing-section);
  text-align: center;
  position: relative;
}

.product-tile-light {
  background-color: var(--colors-canvas); /* White #ffffff */
  color: var(--colors-ink);
}

.product-tile-parchment {
  background-color: var(--colors-canvas-parchment); /* Parchment #f5f5f7 */
  color: var(--colors-ink);
}

.product-tile-dark {
  background-color: var(--colors-surface-tile-1); /* Near-Black Tile 1 #272729 */
  color: var(--colors-body-on-dark);
}

.product-tile-dark-2 {
  background-color: var(--colors-surface-tile-2); /* Near-Black Tile 2 #2a2a2c */
  color: var(--colors-body-on-dark);
}

/* Header Inside Tile */
.tile-header {
  max-width: 780px;
  margin-inline: auto;
  margin-bottom: var(--spacing-xl);
}

.tile-title {
  margin-bottom: 8px;
}

.tile-lead {
  margin-bottom: var(--spacing-md);
}

.tile-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
  flex-wrap: wrap;
}

/* Grids */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--spacing-lg);
  text-align: left;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-lg);
  text-align: left;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-md);
  text-align: left;
}

/* Footer (Parchment with Dense Link Stacks at 2.41 line-height) */
.site-footer {
  background-color: var(--colors-canvas-parchment);
  color: var(--colors-ink-muted-80);
  padding: 64px var(--spacing-lg);
  border-top: 1px solid var(--colors-divider-soft);
  font-size: 14px;
}

.footer-top {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xxl);
}

.footer-col h4 {
  font-size: 14px;
  font-weight: var(--weight-semibold);
  color: var(--colors-ink);
  margin-bottom: 12px;
}

.footer-links-dense {
  list-style: none;
  display: flex;
  flex-direction: column;
}

.footer-links-dense a {
  color: var(--colors-ink-muted-80);
  text-decoration: none;
  line-height: 2.41; /* typography.dense-link */
  font-size: 13px;
}

.footer-links-dense a:hover {
  text-decoration: underline;
  color: var(--colors-ink);
}

.footer-bottom {
  border-top: 1px solid var(--colors-divider-soft);
  padding-top: var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--colors-ink-muted-48);
}

/* Responsive */
@media (max-width: 834px) {
  .global-nav-links {
    display: none;
  }
  .sub-nav-menu {
    display: none;
  }
  .grid-2, .grid-3, .grid-4, .footer-top {
    grid-template-columns: 1fr;
  }
}

/* Mobile Smartphone Optimization (600px & below) */
@media (max-width: 600px) {
  .container,
  .container-wide {
    padding-inline: 16px;
  }

  .product-tile {
    padding-block: 52px;
  }

  .tile-header {
    margin-bottom: 20px;
  }

  .sub-nav-category {
    font-size: 15px;
    letter-spacing: -0.2px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 175px;
  }

  .site-footer {
    padding: 44px 16px 28px 16px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .hero-display {
    font-size: clamp(26px, 7.5vw, 34px);
    line-height: 1.15;
  }

  .display-lg {
    font-size: clamp(22px, 6vw, 28px);
  }

  .lead {
    font-size: 17px;
    line-height: 1.4;
  }
}