/* ============================================================
 *  Header (顶部导航)
 * ============================================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: var(--sp-4) 0;
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: saturate(180%) blur(24px);
  -webkit-backdrop-filter: saturate(180%) blur(24px);
  border-bottom: 1px solid transparent;
  transition: all var(--duration) var(--ease-out);
}

.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.92);
  border-bottom-color: var(--color-border);
  box-shadow: var(--shadow-sm);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-8);
}

.site-logo {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  font-weight: 600;
  font-size: var(--fs-md);
  color: var(--color-text);
}

.site-logo__mark {
  width: 36px;
  height: 36px;
  flex: none;
  background: var(--gradient-primary);
  border-radius: var(--radius-sm);
  display: grid;
  place-items: center;
  color: #fff;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 14px;
  letter-spacing: -0.02em;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.site-logo__mark::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 30%, rgba(255, 255, 255, 0.3) 50%, transparent 70%);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
}

.site-nav__link {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  font-size: var(--fs-base);
  color: var(--color-text-secondary);
  border-radius: var(--radius-full);
  position: relative;
  transition: all var(--duration) var(--ease-out);
}

.site-nav__link:hover {
  color: var(--color-primary);
  background: var(--color-primary-soft);
}

.site-nav__link.is-active {
  color: var(--color-primary);
  background: var(--color-primary-soft);
  font-weight: 500;
}

.site-nav__icon {
  width: 16px;
  height: 16px;
  flex: none;
}

.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  align-items: center;
  justify-content: center;
  color: var(--color-text);
}

@media (max-width: 900px) {
  .menu-toggle { display: inline-flex; }
  .site-nav {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    align-items: stretch;
    padding: var(--sp-4);
    gap: var(--sp-1);
    transform: translateY(-12px);
    opacity: 0;
    pointer-events: none;
    transition: all var(--duration) var(--ease-out);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
  }
  .site-nav.is-open {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
  }
  .site-nav__link {
    justify-content: flex-start;
    padding: var(--sp-3) var(--sp-4);
  }
}

/* ============================================================
 *  Hero (项目规划主视觉 + 项目轮播)
 * ============================================================ */
.hero {
  position: relative;
  padding: 120px 0 var(--sp-12);
  overflow: hidden;
  background:
    radial-gradient(ellipse at 20% 0%, rgba(37, 99, 235, 0.12) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 30%, rgba(124, 58, 237, 0.10) 0%, transparent 50%),
    linear-gradient(180deg, #f0f5ff 0%, #fafbff 100%);
}

/* 网格背景 */
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(37, 99, 235, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.06) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(ellipse at 50% 30%, #000 0%, transparent 70%);
  -webkit-mask-image: radial-gradient(ellipse at 50% 30%, #000 0%, transparent 70%);
  pointer-events: none;
}

/* 浮动装饰球 */
.hero__deco {
  position: absolute;
  pointer-events: none;
  z-index: 1;
}

.hero__deco--ai {
  top: 80px;
  left: 4%;
  width: 110px;
  height: 110px;
  animation: float-y 7s ease-in-out infinite;
}

.hero__deco--xr {
  top: 100px;
  right: 4%;
  width: 130px;
  height: 130px;
  animation: float-y 6s ease-in-out -3s infinite;
}

@keyframes float-y {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50%      { transform: translateY(-18px) rotate(2deg); }
}

@media (max-width: 1100px) {
  .hero__deco--ai, .hero__deco--xr { display: none; }
}

/* Hero 标题 */
.hero__title-wrap {
  text-align: center;
  margin-bottom: var(--sp-10);
  position: relative;
  z-index: 2;
}

.hero__title {
  font-family: var(--font-display);
  font-size: clamp(36px, 5.5vw, 64px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.02em;
  background: linear-gradient(180deg, #1e293b 0%, #2563eb 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: var(--sp-3);
}

.hero__subtitle {
  font-family: var(--font-display);
  font-size: clamp(11px, 1vw, 14px);
  letter-spacing: 0.4em;
  color: var(--color-text-tertiary);
  font-weight: 500;
  text-transform: uppercase;
  margin-bottom: var(--sp-6);
}

.hero__tagline {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
  font-size: var(--fs-md);
  color: var(--color-text-secondary);
}

.hero__tagline::before,
.hero__tagline::after {
  content: "";
  width: 32px;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--color-primary-light));
}

.hero__tagline::after {
  background: linear-gradient(90deg, var(--color-primary-light), transparent);
}

/* Hero 主轮播卡片 */
.hero-carousel {
  position: relative;
  z-index: 2;
  max-width: 1180px;
  margin: 0 auto;
}

.hero-card {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: var(--sp-8);
  align-items: center;
  padding: var(--sp-10);
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.9);
  border-radius: var(--radius-2xl);
  box-shadow:
    0 4px 16px rgba(15, 23, 42, 0.04),
    0 24px 64px rgba(37, 99, 235, 0.10);
  overflow: hidden;
  min-height: 360px;
}

.hero-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-primary), var(--color-accent), transparent);
}

.hero-card__index {
  font-family: var(--font-display);
  font-size: var(--fs-sm);
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--color-primary);
  margin-bottom: var(--sp-4);
}

.hero-card__index strong {
  font-size: var(--fs-lg);
  font-weight: 700;
}

.hero-card__index .sep {
  color: var(--color-text-tertiary);
  margin: 0 var(--sp-2);
  font-weight: 400;
}

.hero-card__title {
  font-family: var(--font-display);
  font-size: clamp(24px, 3vw, 38px);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
  color: var(--color-text);
  margin-bottom: var(--sp-4);
}

.hero-card__desc {
  font-size: var(--fs-md);
  line-height: 1.7;
  color: var(--color-text-secondary);
  margin-bottom: var(--sp-5);
  max-width: 460px;
}

.hero-card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  margin-bottom: var(--sp-5);
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: var(--sp-1) var(--sp-4);
  font-size: var(--fs-xs);
  font-weight: 500;
  border-radius: var(--radius-full);
  letter-spacing: 0.02em;
}

.tag--blue {
  background: linear-gradient(135deg, #dbeafe, #bfdbfe);
  color: #1e40af;
}

.tag--purple {
  background: linear-gradient(135deg, #ede9fe, #ddd6fe);
  color: #6d28d9;
}

.tag--pink {
  background: linear-gradient(135deg, #fce7f3, #fbcfe8);
  color: #be185d;
}

.tag--cyan {
  background: linear-gradient(135deg, #cffafe, #a5f3fc);
  color: #0e7490;
}

.tag--orange {
  background: linear-gradient(135deg, #fed7aa, #fdba74);
  color: #c2410c;
}

.tag--teal {
  background: linear-gradient(135deg, #ccfbf1, #99f6e4);
  color: #0f766e;
}

.hero-card__chips {
  display: flex;
  gap: var(--sp-3);
  flex-wrap: wrap;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
  font-size: var(--fs-sm);
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-secondary);
  transition: all var(--duration) var(--ease-out);
}

.chip:hover {
  border-color: var(--color-primary-light);
  color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.chip__icon {
  width: 14px;
  height: 14px;
  flex: none;
}

/* Hero 卡片右侧媒体区域 */
.hero-card__media {
  position: relative;
  border-radius: var(--radius-xl);
  overflow: hidden;
  background: linear-gradient(135deg, #1e1b4b 0%, #312e81 100%);
  aspect-ratio: 16 / 11;
  box-shadow: var(--shadow-lg);
}

.hero-card__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hero-card__media .media-placeholder {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: rgba(255, 255, 255, 0.5);
  font-family: var(--font-mono);
  font-size: var(--fs-sm);
  letter-spacing: 0.1em;
  background:
    radial-gradient(circle at 30% 30%, rgba(96, 165, 250, 0.3) 0%, transparent 50%),
    radial-gradient(circle at 70% 70%, rgba(124, 58, 237, 0.3) 0%, transparent 50%),
    linear-gradient(135deg, #1e1b4b 0%, #312e81 100%);
  text-align: center;
  padding: var(--sp-6);
}

/* Hero 轮播按钮 */
.hero-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  border: 1px solid var(--color-border);
  display: grid;
  place-items: center;
  color: var(--color-text-secondary);
  box-shadow: var(--shadow-md);
  transition: all var(--duration) var(--ease-out);
  z-index: 3;
}

.hero-arrow:hover {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
  transform: translateY(-50%) scale(1.05);
}

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

@media (max-width: 1280px) {
  .hero-arrow--prev { left: 8px; }
  .hero-arrow--next { right: 8px; }
}

/* Hero 轮播指示器 */
.hero-dots {
  display: flex;
  justify-content: center;
  gap: var(--sp-2);
  margin-top: var(--sp-6);
}

.hero-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-border);
  transition: all var(--duration) var(--ease-out);
}

.hero-dot.is-active {
  width: 28px;
  border-radius: var(--radius-full);
  background: var(--gradient-primary);
}

@media (max-width: 768px) {
  .hero {
    padding: 100px 0 var(--sp-8);
  }
  .hero-card {
    grid-template-columns: 1fr;
    padding: var(--sp-6);
    min-height: auto;
  }
  .hero-card__media {
    order: -1;
    aspect-ratio: 16 / 10;
  }
}