/* ========== Boya Website - Design System ========== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --bg-dark: #1d1d1f;
  --text: #1d1d1f;
  --text-secondary: #6e6e73;
  --text-tertiary: #86868b;
  --accent: #0071e3;
  --accent-hover: #0077ed;
  --accent-light: #e8f4fd;
  --border: #d2d2d7;
  --border-light: #e8e8ed;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.08);
  --radius-sm: 12px;
  --radius-md: 18px;
  --radius-lg: 24px;
  --radius-full: 980px;
  --transition: 0.35s cubic-bezier(0.25, 0.1, 0.25, 1);
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  overflow-x: hidden;
  letter-spacing: -0.01em;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== Navigation ========== */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid transparent;
  transition: background var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.navbar.scrolled {
  background: rgba(255, 255, 255, 0.92);
  border-bottom: 1px solid var(--border-light);
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.02);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 52px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text);
}

.nav-logo .logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
  border-radius: 6px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 28px;
}

.nav-menu a {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  transition: color var(--transition);
  padding: 6px 0;
  position: relative;
}

.nav-menu a:hover,
.nav-menu a.active {
  color: var(--text);
}

.nav-menu a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--accent);
  border-radius: 2px;
}

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

.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ========== Hero ========== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  padding: 120px 24px 80px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, #f0f4ff 0%, #ffffff 100%);
  z-index: 0;
}

.hero-bg::after {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(0, 113, 227, 0.06) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 680px;
}

.badge {
  display: inline-block;
  padding: 6px 16px;
  background: var(--accent-light);
  color: var(--accent);
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  letter-spacing: 0.04em;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
  margin-bottom: 20px;
  color: var(--text);
}

.hero h1 .highlight {
  background: linear-gradient(135deg, #0071e3, #40a9ff);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero .desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 36px;
  line-height: 1.7;
  max-width: 520px;
  margin-left: auto;
  margin-right: auto;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 1;
}

.arrow {
  width: 24px;
  height: 24px;
  border-right: 2px solid var(--text-tertiary);
  border-bottom: 2px solid var(--text-tertiary);
  transform: rotate(45deg);
  animation: scrollBounce 2s ease infinite;
}

@keyframes scrollBounce {
  0%, 100% { opacity: 0.3; transform: rotate(45deg) translate(0, 0); }
  50% { opacity: 1; transform: rotate(45deg) translate(6px, 6px); }
}

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 28px;
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: -0.01em;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
  font-family: inherit;
  white-space: nowrap;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: scale(1.03);
  box-shadow: 0 4px 16px rgba(0, 113, 227, 0.3);
}

.btn-outline {
  background: transparent;
  color: var(--accent);
  border: 1px solid var(--accent);
}

.btn-outline:hover {
  background: var(--accent);
  color: #fff;
}

/* ========== Sections ========== */
.section {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-header .label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

.section-header h2 {
  font-size: 2.5rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
  color: var(--text);
}

.section-header .desc {
  font-size: 1rem;
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto;
}

.label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 12px;
}

/* ========== About ========== */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.about-image {
  position: relative;
  background: linear-gradient(135deg, #f0f4ff, #e8f4fd);
  border-radius: var(--radius-lg);
  min-height: 360px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 5rem;
  overflow: hidden;
}

.about-image .placeholder {
  opacity: 0.6;
}

.stat-card {
  position: absolute;
  bottom: 24px;
  right: 24px;
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 16px 24px;
  box-shadow: var(--shadow-md);
  text-align: center;
}

.stat-card .number {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent);
  line-height: 1.2;
}

.stat-card .text {
  font-size: 0.75rem;
  color: var(--text-tertiary);
}

.about-text h2 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  color: var(--text);
}

.about-text p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.about-stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 24px 0;
}

.about-stat {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 16px;
  background: var(--bg-alt);
  border-radius: var(--radius-sm);
}

.about-stat .stat-icon {
  font-size: 1.5rem;
}

.stat-info .stat-value {
  font-size: 0.9375rem;
  font-weight: 700;
  color: var(--text);
}

.stat-info .stat-label {
  font-size: 0.75rem;
  color: var(--text-tertiary);
  margin-top: 2px;
}

/* ========== Category Nav ========== */
.category-nav {
  display: flex;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 32px;
  padding-bottom: 8px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.category-nav::-webkit-scrollbar {
  height: 4px;
}

.category-nav::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 2px;
}

.category-nav-btn {
  padding: 8px 20px;
  border: 1px solid var(--border-light);
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  font-family: inherit;
  color: var(--text-secondary);
  background: var(--bg);
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.category-nav-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.category-nav-btn.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.category-nav-loading {
  text-align: center;
  color: var(--text-tertiary);
  font-size: 0.875rem;
  padding: 12px;
}

/* ========== Gallery ========== */
.gallery-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 16px;
}

.gallery-item {
  position: relative;
  border-radius: var(--radius-sm);
  overflow: hidden;
  cursor: pointer;
  aspect-ratio: 1;
  background: var(--bg-alt);
}

.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.gallery-item:hover img {
  transform: scale(1.05);
}

.gallery-item .overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 60%, rgba(0, 0, 0, 0.6));
  opacity: 0;
  transition: opacity 0.3s ease;
  display: flex;
  align-items: flex-end;
  padding: 16px;
}

.gallery-item:hover .overlay {
  opacity: 1;
}

.gallery-item .overlay span {
  color: #fff;
  font-size: 0.8125rem;
  font-weight: 500;
}

.category-section {
  margin-bottom: 40px;
}

.category-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--border-light);
  display: flex;
  align-items: center;
  gap: 10px;
}

.category-title .count {
  font-size: 0.8125rem;
  font-weight: 400;
  color: var(--text-tertiary);
}

/* ========== Lightbox ========== */
.lightbox {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.92);
  z-index: 3000;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
}

.lightbox img {
  max-width: 90vw;
  max-height: 80vh;
  object-fit: contain;
  border-radius: 4px;
}

.lightbox-close {
  position: absolute;
  top: 20px;
  right: 24px;
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
  border: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  font-size: 1.5rem;
  cursor: pointer;
  transition: background var(--transition);
}

.lightbox-close:hover {
  background: rgba(255, 255, 255, 0.3);
}

.lightbox-prev,
.lightbox-next {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
  border: none;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  font-size: 1.5rem;
  cursor: pointer;
  transition: background var(--transition);
}

.lightbox-prev:hover,
.lightbox-next:hover {
  background: rgba(255, 255, 255, 0.3);
}

.lightbox-prev { left: 24px; }
.lightbox-next { right: 24px; }

.lightbox-counter {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.8125rem;
  margin-top: 12px;
}

.lightbox-info {
  color: rgba(255, 255, 255, 0.8);
  font-size: 0.875rem;
  margin-top: 4px;
}

/* ========== Advantage ========== */
.advantage-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.advantage-card {
  padding: 32px 28px;
  background: var(--bg);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  transition: all var(--transition);
}

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

.advantage-card .adv-icon {
  font-size: 2rem;
  display: block;
  margin-bottom: 16px;
}

.advantage-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--text);
}

.advantage-card p {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ========== CTA ========== */
.cta-strip {
  padding: 80px 0;
  text-align: center;
  background: linear-gradient(135deg, #f0f4ff, #e8f4fd);
}

.cta-strip h3 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text);
}

.cta-strip p {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  margin-bottom: 28px;
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

/* ========== Footer ========== */
#contact.footer {
  background: var(--bg-dark);
  color: #a1a1a6;
  padding: 60px 0 0;
}

#contact.footer a {
  color: #a1a1a6;
  transition: color var(--transition);
}

#contact.footer a:hover {
  color: #fff;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.5fr;
  gap: 40px;
  padding-bottom: 40px;
}

.footer-about .logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.05rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 16px;
}

.footer-about .logo .logo-img {
  width: 32px;
  height: 32px;
  object-fit: contain;
  border-radius: 6px;
}

.footer-about p {
  font-size: 0.8125rem;
  line-height: 1.8;
  color: #a1a1a6;
}

.footer-links h4,
.footer-contact h4 {
  font-size: 0.8125rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 16px;
  letter-spacing: 0.02em;
}

.footer-links a {
  display: block;
  font-size: 0.8125rem;
  color: #a1a1a6;
  margin-bottom: 10px;
  transition: color var(--transition);
}

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

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 10px;
  font-size: 0.8125rem;
  color: #a1a1a6;
}

.contact-item .icon {
  font-size: 0.9rem;
  flex-shrink: 0;
  width: 18px;
  text-align: center;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 20px 0;
  font-size: 0.75rem;
}

/* ========== Back to Top ========== */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  border: none;
  font-size: 1.25rem;
  cursor: pointer;
  opacity: 0;
  transform: translateY(20px);
  transition: all var(--transition);
  z-index: 999;
  box-shadow: var(--shadow-md);
}

.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
}

/* ========== Reveal Animation ========== */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

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

/* ========== Loading ========== */
.loading {
  text-align: center;
  padding: 60px 20px;
}

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

@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }

  .nav-menu {
    position: fixed;
    top: 52px;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(20px);
    flex-direction: column;
    gap: 0;
    padding: 16px 0;
    border-bottom: 1px solid var(--border-light);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-10px);
    transition: all var(--transition);
  }

  .nav-menu.open {
    opacity: 1;
    pointer-events: all;
    transform: translateY(0);
  }

  .nav-menu a {
    padding: 14px 24px;
    width: 100%;
    font-size: 0.9375rem;
  }

  .nav-menu a.active::after {
    display: none;
  }

  .nav-menu a.active {
    background: var(--accent-light);
    color: var(--accent);
  }

  .nav-toggle {
    display: flex;
  }

  .hero h1 {
    font-size: 2.2rem;
  }

  .hero .desc {
    font-size: 0.9375rem;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .about-image {
    min-height: 250px;
  }

  .about-stats {
    grid-template-columns: 1fr;
  }

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

  .gallery-grid {
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 10px;
  }

  .section-header h2 {
    font-size: 1.75rem;
  }

  .section {
    padding: 60px 0;
  }

  .cta-strip h3 {
    font-size: 1.35rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .lightbox-prev,
  .lightbox-next {
    width: 36px;
    height: 36px;
    font-size: 1rem;
  }

  .lightbox-prev { left: 12px; }
  .lightbox-next { right: 12px; }

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 1.8rem;
  }

  .hero-buttons {
    flex-direction: column;
    align-items: center;
  }

  .hero-buttons .btn {
    width: 100%;
    max-width: 260px;
  }

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

  .category-nav {
    gap: 6px;
  }

  .category-nav-btn {
    padding: 6px 14px;
    font-size: 0.75rem;
  }
}