/* ============================================================
   LEIBROTHER — MV 私人定制工作室
   Redesigned with impeccable principles
   Direction: Cinematic warmth × Editorial elegance
   ============================================================ */

/* --- CSS Custom Properties (OKLCH palette) --- */
:root {
  /* Warm-tinted neutrals — never pure gray */
  --bg: oklch(95% 0.01 55);
  --bg-warm: oklch(94% 0.012 60);
  --text-primary: oklch(18% 0.008 60);
  --text-secondary: oklch(42% 0.01 60);
  --text-muted: oklch(55% 0.012 60);
  --border: oklch(88% 0.008 60);
  --border-strong: oklch(72% 0.012 60);

  /* Accent — warm terracotta, not AI purple */
  --accent: oklch(58% 0.16 35);
  --accent-hover: oklch(50% 0.17 35);
  --accent-subtle: oklch(92% 0.025 35);

  /* Semantic */
  --success: oklch(62% 0.14 150);
  --error: oklch(55% 0.18 25);

  /* Typography */
  --font-serif: 'Noto Serif SC', 'Source Han Serif SC', 'STSong', serif;
  --font-sans: 'Source Sans 3', 'Noto Sans SC', system-ui, sans-serif;

  /* Modular scale (1.333 perfect fourth) */
  --text-xs: clamp(0.65rem, 0.6rem + 0.25vw, 0.75rem);
  --text-sm: clamp(0.8rem, 0.75rem + 0.25vw, 0.875rem);
  --text-base: clamp(0.95rem, 0.9rem + 0.25vw, 1.05rem);
  --text-lg: clamp(1.15rem, 1.05rem + 0.5vw, 1.4rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.2vw, 2.2rem);
  --text-2xl: clamp(2rem, 1.4rem + 2.5vw, 3.5rem);
  --text-3xl: clamp(2.8rem, 1.8rem + 4vw, 5.5rem);

  /* Spacing (4pt base × line-height 1.6 = 24px rhythm) */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4.5rem;
  --space-4xl: 6rem;

  /* Motion — smooth cinematic, never bounce */
  --ease-out: cubic-bezier(0.22, 1, 0.36, 1);
  --duration-fast: 100ms;
  --duration-normal: 300ms;
  --duration-slow: 500ms;

  /* Container */
  --container-max: 1400px;
  --container-narrow: 720px;
}

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

html {
  font-size: 100%; /* Respect user browser settings */
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: #f0ebe4;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

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

a {
  color: inherit;
  text-decoration: none;
}

/* --- Navigation --- */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: oklch(97% 0.005 60 / 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: var(--space-md) var(--space-xl);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.nav-logo {
  height: 52px;
  width: auto;
  border-radius: 6px;
}

.nav-title {
  font-family: var(--font-sans);
  font-size: var(--text-lg);
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-primary);
}

.nav-links {
  display: flex;
  gap: var(--space-lg);
}

.nav-link {
  font-size: var(--text-lg);
  font-weight: 500;
  color: var(--text-secondary);
  padding: var(--space-xs) 0;
  border-bottom: 2px solid transparent;
  transition: color var(--duration-normal) var(--ease-out),
              border-color var(--duration-normal) var(--ease-out);
}

.nav-link:hover {
  color: var(--text-primary);
  border-bottom-color: var(--accent);
}

.nav-link--premium {
  color: #f0c040 !important;
  position: relative;
}
.nav-link--premium:hover {
  color: #ffd700 !important;
  border-bottom-color: #f0c040 !important;
}

.nav-link--demo {
  color: var(--accent) !important;
  position: relative;
  font-weight: 600;
}
.nav-link--demo::after {
  content: 'NEW';
  position: absolute;
  top: -6px;
  right: -22px;
  font-size: 0.55rem;
  font-weight: 700;
  padding: 1px 5px;
  border-radius: 4px;
  background: var(--accent);
  color: #fff;
  line-height: 1.3;
}
.nav-link--demo:hover {
  color: var(--accent-hover) !important;
  border-bottom-color: var(--accent) !important;
}

/* --- Hero --- */
.hero {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  padding-top: 80px; /* nav height */
  overflow: hidden;
}

.hero-content {
  padding: var(--space-4xl) var(--space-3xl);
  max-width: 680px;
}

.hero-eyebrow {
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--space-lg);
}

.hero-heading {
  font-family: var(--font-serif);
  font-size: var(--text-3xl);
  font-weight: 700;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: var(--space-xl);
  letter-spacing: -0.01em;
}

.hero-heading em {
  font-style: normal;
  color: var(--accent);
}

.hero-lead {
  font-size: var(--text-lg);
  font-weight: 300;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: var(--space-2xl);
  max-width: 50ch;
}

/* --- Buttons --- */
.cta-primary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 600;
  color: oklch(98% 0 0);
  background: var(--accent);
  padding: var(--space-md) var(--space-xl);
  border-radius: 6px;
  transition: background var(--duration-normal) var(--ease-out),
              transform var(--duration-normal) var(--ease-out);
}

.cta-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
}

.cta-primary:active {
  transform: translateY(0);
}

.cta-primary--large {
  font-size: var(--text-lg);
  padding: var(--space-lg) var(--space-2xl);
}

/* --- Hero Visual (film grain background) --- */
.hero-visual {
  position: relative;
  height: 100%;
  min-height: 500px;
  background:
    linear-gradient(135deg, oklch(85% 0.02 35) 0%, oklch(78% 0.03 45) 100%);
  overflow: hidden;
}

.film-grain {
  position: absolute;
  inset: 0;
  opacity: 0.04;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  background-size: 128px 128px;
  animation: grain 0.5s steps(1) infinite;
}

@keyframes grain {
  0%, 100% { transform: translate(0, 0); }
  10% { transform: translate(-5%, -10%); }
  20% { transform: translate(-15%, 5%); }
  30% { transform: translate(7%, -25%); }
  40% { transform: translate(-5%, 25%); }
  50% { transform: translate(-15%, 10%); }
  60% { transform: translate(15%, 0%); }
  70% { transform: translate(0%, 15%); }
  80% { transform: translate(3%, 35%); }
  90% { transform: translate(-10%, 10%); }
}

/* --- Works Section --- */
.works {
  padding: var(--space-4xl) var(--space-xl);
  max-width: var(--container-max);
  margin: 0 auto;
}

.works-header {
  margin-bottom: var(--space-3xl);
  padding-left: var(--space-md);
  border-left: 3px solid var(--accent);
}

.section-heading {
  font-family: var(--font-serif);
  font-size: var(--text-2xl);
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
  margin-bottom: var(--space-sm);
}

.section-lead {
  font-size: var(--text-lg);
  font-weight: 300;
  color: var(--text-muted);
}

/* --- Work Items (editorial layout, not cards) --- */
.works-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3xl);
}

.work-item {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: var(--space-3xl);
  align-items: center;
  padding: var(--space-2xl) 0;
  border-bottom: 1px solid var(--border);
}

.work-item:last-child {
  border-bottom: none;
}

.work-item--reversed {
  grid-template-columns: 1fr 1.2fr;
}

.work-item--reversed .work-visual {
  order: 2;
}

.work-item--reversed .work-details {
  order: 1;
}

/* --- Video Wrapper (cinematic 16:9) --- */
.video-wrapper {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: var(--text-primary);
  border-radius: 4px;
  overflow: hidden;
}

.video-wrapper iframe {
  width: 100%;
  height: 100%;
  border: none;
}

/* --- Work Details --- */
.work-number {
  display: block;
  font-family: var(--font-serif);
  font-size: var(--text-xl);
  font-weight: 400;
  color: var(--accent);
  margin-bottom: var(--space-sm);
  opacity: 0.7;
}

.work-title {
  font-family: var(--font-serif);
  font-size: var(--text-xl);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: var(--space-md);
}

.work-description {
  font-size: var(--text-base);
  font-weight: 300;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: var(--space-lg);
  max-width: 55ch;
}

/* --- Tags --- */
.work-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.tag {
  font-size: var(--text-xs);
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--text-muted);
  background: var(--bg-warm);
  padding: var(--space-xs) var(--space-md);
  border-radius: 3px;
  border: 1px solid var(--border);
}

/* --- CTA Section --- */
.cta-section {
  padding: var(--space-4xl) var(--space-xl);
  text-align: center;
  background: var(--bg-warm);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.cta-content {
  max-width: 600px;
  margin: 0 auto;
}

.cta-heading {
  font-family: var(--font-serif);
  font-size: var(--text-2xl);
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: var(--space-2xl);
}

/* --- Footer --- */
.site-footer {
  padding: var(--space-2xl) var(--space-xl);
  background: var(--text-primary);
  color: oklch(90% 0.005 60);
}

.footer-inner {
  max-width: var(--container-max);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer-brand {
  font-size: var(--text-sm);
  font-weight: 500;
  letter-spacing: 0.05em;
}

.footer-copy {
  font-size: var(--text-xs);
  color: oklch(65% 0.008 60);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */

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

  .hero-content {
    padding: var(--space-3xl) var(--space-xl);
    text-align: center;
  }

  .hero-lead {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-visual {
    min-height: 300px;
  }

  .work-item,
  .work-item--reversed {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .work-item--reversed .work-visual {
    order: 0;
  }

  .work-item--reversed .work-details {
    order: 0;
  }

  .works-header {
    text-align: left;
  }
}

@media (max-width: 600px) {
  .nav-inner {
    padding: var(--space-sm) var(--space-md);
  }

  .nav-logo {
    height: 36px;
  }

  .nav-title {
    font-size: var(--text-xs);
  }

  .nav-links {
    gap: var(--space-md);
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding-bottom: 2px;
  }

  .nav-links::-webkit-scrollbar { display: none; }

  .nav-link {
    font-size: var(--text-sm);
    white-space: nowrap;
  }

  .hero-content {
    padding: var(--space-2xl) var(--space-lg);
  }

  .hero-heading {
    font-size: var(--text-2xl);
  }

  .hero-lead {
    font-size: var(--text-base);
  }

  .hero-visual {
    min-height: auto;
    padding-top: 40%; /* 16:9-ish aspect ratio for workflow */
  }

  .works {
    padding: var(--space-3xl) var(--space-lg);
  }

  .section-heading {
    font-size: var(--text-xl);
  }

  .work-item,
  .work-item--reversed {
    gap: var(--space-lg);
  }

  .work-title {
    font-size: var(--text-lg);
  }

  .work-description {
    font-size: var(--text-sm);
  }

  .cta-section {
    padding: var(--space-3xl) var(--space-lg);
  }

  .cta-heading {
    font-size: var(--text-xl);
  }

  .footer-inner {
    flex-direction: column;
    gap: var(--space-sm);
    text-align: center;
  }

  .cta-primary--large {
    font-size: var(--text-base);
    padding: var(--space-md) var(--space-xl);
  }
}

@media (max-width: 420px) {
  .nav-inner {
    flex-wrap: wrap;
    gap: var(--space-xs);
  }

  .nav-links {
    width: 100%;
    justify-content: flex-start;
    padding: var(--space-xs) 0;
    overflow-x: auto;
  }

  .nav-link {
    font-size: var(--text-xs);
  }

  .hero-content {
    padding: var(--space-xl) var(--space-md);
  }

  .hero-heading {
    font-size: var(--text-xl);
  }

  .works {
    padding: var(--space-2xl) var(--space-md);
  }

  .work-item,
  .work-item--reversed {
    gap: var(--space-md);
  }
}

/* ============================================================
   REDUCED MOTION
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .film-grain {
    animation: none;
  }
}