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

:root {
  --c-white: #FFFFFF;
  --c-bg: #FFFFFF;
  --c-text: #1a1a1a;
  --c-text-light: #888888;
  --c-text-lighter: #b0b0b0;
  --c-border: #eeeeee;
  --c-accent: #1a1a1a;
  --c-dark: #1a1a1a;
  --font-serif: 'Noto Serif SC', 'Source Serif 4', Georgia, serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
}

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  color: var(--c-text);
  background: var(--c-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; }

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 40px; }

/* ========== Header ========== */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid transparent;
  transition: all var(--transition);
}

.header.scrolled { border-bottom-color: var(--c-border); }

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 96px;
}

.logo { display: flex; align-items: center; cursor: pointer; }

.logo-img {
  height: 76px;
  width: auto;
  display: block;
  transition: opacity var(--transition);
}

.logo:hover .logo-img { opacity: 0.8; }

.nav { display: flex; gap: 48px; }

.nav-link {
  font-size: 15px;
  font-weight: 500;
  color: var(--c-text-light);
  transition: color var(--transition);
  position: relative;
  padding: 4px 0;
}

.nav-link:hover, .nav-link.active { color: var(--c-text); }

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -2px; left: 0; right: 0;
  height: 2px;
  background: var(--c-text);
}

.header-actions { display: flex; align-items: center; gap: 20px; }

.lang-toggle {
  background: none;
  border: 1px solid var(--c-border);
  border-radius: 4px;
  padding: 6px 14px;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 13px;
  font-weight: 500;
  color: var(--c-text);
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 2px;
}

.lang-toggle:hover { border-color: var(--c-text); }

.lang-current { color: var(--c-text); font-weight: 600; }
.lang-switch { color: var(--c-text-lighter); }

.menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.menu-toggle span {
  width: 24px;
  height: 2px;
  background: var(--c-text);
  transition: all var(--transition);
}

/* ========== Hero ========== */
.hero {
  min-height: 70vh;
  display: flex;
  align-items: center;
  padding-top: 96px;
  background: var(--c-white);
}

.hero-content { text-align: center; }

.hero-title {
  font-family: var(--font-serif);
  font-size: 64px;
  font-weight: 700;
  line-height: 1.15;
  color: var(--c-text);
  margin-bottom: 24px;
}

.hero-title span { display: block; }

.hero-title-accent {
  font-weight: 400;
  color: var(--c-text-light);
}

html[lang="en"] .hero-title { font-size: 56px; }

.hero-subtitle {
  font-size: 17px;
  color: var(--c-text-light);
  max-width: 560px;
  margin: 0 auto;
  line-height: 1.8;
}

/* ========== Section ========== */
.section { padding: 120px 0; }

.section-header { text-align: center; margin-bottom: 64px; }

.section-title {
  font-family: var(--font-serif);
  font-size: 36px;
  font-weight: 700;
  color: var(--c-text);
  margin-bottom: 12px;
}

.section-desc {
  font-size: 16px;
  color: var(--c-text-light);
}

/* ========== Products ========== */
.product-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.product-card {
  background: var(--c-white);
  border: 1px solid var(--c-border);
  border-radius: 8px;
  overflow: hidden;
  transition: all var(--transition);
}

.product-card:hover {
  border-color: var(--c-text-lighter);
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.06);
}

.product-img-wrap {
  width: 100%;
  aspect-ratio: 1 / 1;
  overflow: hidden;
  background: #f8f8f8;
}

.product-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s ease;
}

.product-card:hover .product-img { transform: scale(1.05); }

.product-body { padding: 20px; }

.product-name {
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 600;
  color: var(--c-text);
  margin-bottom: 6px;
}

.product-desc {
  font-size: 13px;
  color: var(--c-text-light);
  line-height: 1.6;
}

/* ========== About ========== */
.about-wrapper { max-width: 800px; margin: 0 auto; text-align: center; }

.about-content { width: 100%; }

.about-text {
  font-size: 17px;
  line-height: 2;
  color: var(--c-text-light);
  margin: 24px 0 48px;
  text-align: left;
}

.about-stats {
  display: flex;
  justify-content: center;
  gap: 64px;
}

.about-stat { text-align: center; }

.about-stat-num {
  font-family: var(--font-serif);
  font-size: 48px;
  font-weight: 700;
  color: var(--c-text);
  line-height: 1;
}

.about-stat-num span { font-size: 28px; font-weight: 400; }

.about-stat-label {
  font-size: 14px;
  color: var(--c-text-light);
  margin-top: 8px;
}

/* ========== Contact ========== */
.section-dark { background: var(--c-dark); }

.contact-wrapper { text-align: center; }

.contact-title {
  font-family: var(--font-serif);
  font-size: 36px;
  font-weight: 700;
  color: var(--c-white);
  margin-bottom: 12px;
}

.contact-desc {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: 48px;
}

.contact-items {
  display: flex;
  justify-content: center;
  gap: 48px;
  flex-wrap: wrap;
}

.contact-item {
  display: flex;
  align-items: center;
  gap: 10px;
  color: rgba(255, 255, 255, 0.8);
  font-size: 15px;
  transition: color var(--transition);
}

.contact-item:hover { color: var(--c-white); }

.contact-item svg { width: 20px; height: 20px; }

/* ========== Footer ========== */
.footer {
  background: var(--c-white);
  border-top: 1px solid var(--c-border);
  padding: 32px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.footer-brand { display: flex; align-items: center; }

.footer-logo-img {
  height: 48px;
  width: auto;
  display: block;
}

.footer-copy {
  font-size: 13px;
  color: var(--c-text-lighter);
}

/* ========== Scroll Reveal ========== */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible { opacity: 1; transform: translateY(0); }

/* ========== Responsive ========== */
@media (max-width: 1024px) {
  .product-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 640px) {
  .header-inner { height: 64px; }
  .logo-img { height: 48px; }
  .hero { padding-top: 64px; min-height: 60vh; }
  .hero-title { font-size: 40px; }
  html[lang="en"] .hero-title { font-size: 36px; }
  .hero-subtitle { font-size: 15px; }

  .nav { display: none; }
  .menu-toggle { display: flex; }

  .nav.nav-open {
    display: flex;
    position: fixed;
    top: 64px; left: 0; right: 0;
    flex-direction: column;
    background: var(--c-white);
    padding: 20px 32px;
    gap: 14px;
    border-bottom: 1px solid var(--c-border);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
  }

  .section { padding: 64px 0; }
  .section-title { font-size: 28px; }
  .product-grid { grid-template-columns: 1fr; }
  .about-stats { gap: 32px; }
  .about-stat-num { font-size: 36px; }
  .contact-title { font-size: 28px; }
  .contact-items { gap: 24px; }
  .footer-inner { flex-direction: column; text-align: center; }
  .footer-logo-img { height: 40px; }
}