/* ========================
   CSS 变量和基础重置
   ======================== */
:root {
  --color-bg: #0f172a;
  --color-bg-section: #111827;
  --color-bg-card: #1e293b;
  --color-bg-header: rgba(15, 23, 42, 0.9);
  --color-text: #f1f5f9;
  --color-text-muted: #94a3b8;
  --color-text-dim: #64748b;
  --color-accent: #22c55e;
  --color-accent-hover: #16a34a;
  --color-border: rgba(255, 255, 255, 0.08);
  --color-border-light: rgba(255, 255, 255, 0.12);
  --font-sans: "PingFang SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --max-width: 960px;
  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 32px;
  --spacing-lg: 64px;
  --spacing-xl: 96px;
  --radius: 8px;
  --radius-lg: 12px;
  --transition: 0.2s ease;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 72px;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

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

ul {
  list-style: none;
}

/* ========================
   全局排版和容器
   ======================== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

.section {
  padding: var(--spacing-xl) 0;
}

.section-title {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
  letter-spacing: 0.5px;
}

.section-subtitle {
  color: var(--color-text-muted);
  font-size: 16px;
  margin-bottom: var(--spacing-lg);
}

/* ========================
   Header 导航栏
   ======================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--color-bg-header);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
  transition: box-shadow var(--transition);
}

.site-header.scrolled {
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: 2px;
}

.main-nav {
  display: flex;
  gap: var(--spacing-md);
}

.main-nav a {
  font-size: 14px;
  color: var(--color-text-muted);
  transition: color var(--transition);
  padding: 4px 0;
}

.main-nav a:hover,
.main-nav a:focus {
  color: var(--color-text);
}

/* 移动端菜单按钮 */
.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}

.menu-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.menu-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ========================
   Hero 区块
   ======================== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 60px;
}

.hero .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-lg);
  align-items: center;
}

.hero h1 {
  font-size: 56px;
  font-weight: 800;
  letter-spacing: 4px;
  line-height: 1.1;
  margin-bottom: var(--spacing-sm);
}

.hero-tagline {
  font-size: 22px;
  color: var(--color-accent);
  font-weight: 500;
  margin-bottom: var(--spacing-sm);
}

.hero-desc {
  font-size: 16px;
  color: var(--color-text-muted);
  line-height: 1.8;
  margin-bottom: var(--spacing-md);
  max-width: 440px;
}

.hero-actions {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

/* ========================
   产品预览占位图
   ======================== */
.preview-placeholder {
  width: 100%;
  aspect-ratio: 4 / 3;
  background: var(--color-bg-card);
  border: 2px dashed var(--color-border-light);
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--color-text-dim);
  font-size: 14px;
  gap: var(--spacing-xs);
}

.preview-placeholder.small {
  aspect-ratio: 3 / 2;
}

.preview-hint {
  font-size: 12px;
  color: var(--color-text-dim);
  opacity: 0.6;
}

/* ========================
   Products 产品卡片
   ======================== */
.product-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-md);
}

.product-card {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}

.product-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
}

.product-image {
  border-radius: var(--radius);
  overflow: hidden;
}

.product-info {
  padding: var(--spacing-sm) var(--spacing-sm) var(--spacing-sm) 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.product-status {
  display: inline-block;
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 20px;
  font-weight: 500;
  margin-bottom: var(--spacing-sm);
  width: fit-content;
}

.status-coming {
  background: rgba(34, 197, 94, 0.15);
  color: var(--color-accent);
}

.status-live {
  background: rgba(59, 130, 246, 0.15);
  color: #60a5fa;
}

.product-info h3 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: var(--spacing-xs);
}

.product-info p {
  font-size: 15px;
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: var(--spacing-xs);
}

.product-detail {
  font-size: 14px;
  color: var(--color-text-dim);
  margin-bottom: 4px;
}

.product-detail strong {
  color: var(--color-text-muted);
}

.product-actions {
  margin-top: var(--spacing-sm);
}

/* ========================
   About 区块
   ======================== */
.about {
  background: var(--color-bg-section);
}

.about-content {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: var(--spacing-lg);
}

.about-text p {
  font-size: 16px;
  color: var(--color-text-muted);
  line-height: 1.9;
  margin-bottom: var(--spacing-sm);
}

.about-focus h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: var(--spacing-sm);
}

.about-focus li {
  font-size: 15px;
  color: var(--color-text-muted);
  padding: var(--spacing-xs) 0;
  border-bottom: 1px solid var(--color-border);
}

.about-focus li:last-child {
  border-bottom: none;
}

/* ========================
   Contact 区块
   ======================== */
.contact-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.contact-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: var(--spacing-sm);
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color var(--transition);
}

a.contact-item:hover,
a.contact-item:focus {
  border-color: var(--color-border-light);
}

.contact-label {
  font-size: 12px;
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.contact-value {
  font-size: 15px;
  color: var(--color-text);
}

.contact-note {
  font-size: 14px;
  color: var(--color-text-dim);
  text-align: center;
}

/* ========================
   Footer
   ======================== */
.site-footer {
  padding: var(--spacing-md) 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.site-footer p {
  font-size: 13px;
  color: var(--color-text-dim);
}

/* ========================
   按钮
   ======================== */
.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  transition: background var(--transition), transform var(--transition);
  cursor: pointer;
  border: none;
}

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

.btn-primary:hover,
.btn-primary:focus {
  background: var(--color-accent-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text-muted);
  border: 1px solid var(--color-border-light);
}

.btn-secondary:hover,
.btn-secondary:focus {
  color: var(--color-text);
  border-color: var(--color-text-dim);
}

.btn-small {
  padding: 8px 18px;
  font-size: 13px;
}

/* focus 可见状态 */
.btn:focus-visible,
.main-nav a:focus-visible,
.contact-item:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

/* ========================
   滚动淡入动画
   ======================== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ========================
   响应式适配
   ======================== */

/* 平板 */
@media (max-width: 768px) {
  .hero .container {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    text-align: center;
  }

  .hero h1 {
    font-size: 40px;
  }

  .hero-desc {
    max-width: 100%;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-preview {
    order: -1;
  }

  .product-card {
    grid-template-columns: 1fr;
  }

  .product-info {
    padding: var(--spacing-sm);
  }

  .about-content {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
  }

  .contact-links {
    grid-template-columns: 1fr;
  }

  /* 移动端导航 */
  .menu-toggle {
    display: flex;
  }

  .main-nav {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background: var(--color-bg-header);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: var(--spacing-sm);
    gap: 0;
    border-bottom: 1px solid var(--color-border);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.3s ease, opacity 0.3s ease;
  }

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

  .main-nav a {
    padding: 12px var(--spacing-sm);
    font-size: 16px;
    border-bottom: 1px solid var(--color-border);
  }

  .main-nav a:last-child {
    border-bottom: none;
  }
}

/* 手机 */
@media (max-width: 480px) {
  :root {
    --spacing-xl: 64px;
    --spacing-lg: 48px;
  }

  .hero h1 {
    font-size: 32px;
    letter-spacing: 2px;
  }

  .hero-tagline {
    font-size: 18px;
  }

  .section-title {
    font-size: 24px;
  }

  .btn {
    padding: 10px 20px;
    font-size: 13px;
  }
}