/* ============================================================
   全局重置 + 排版 + 工具类
   ============================================================ */

/* --- 重置 --- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--od-font-ui);
  background: var(--od-bg-base);
  color: var(--od-text-primary);
  overflow-x: hidden;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

/* --- 容器 --- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--od-space-xl);
}

/* --- Section --- */
.section-padding {
  padding: 100px 0;
}
.section-title {
  font-size: 36px;
  font-weight: 700;
  text-align: center;
  margin-bottom: var(--od-space-lg);
  letter-spacing: 0.03em;
}
.section-subtitle {
  font-size: var(--od-text-xl);
  color: var(--od-text-secondary);
  text-align: center;
  max-width: 640px;
  margin: 0 auto 56px;
  line-height: 1.8;
}

/* --- 滚动渐入动画 --- */
.fade-section {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}
.fade-section.visible {
  opacity: 1;
  transform: translateY(0);
}
.stagger-1 { transition-delay: 0.1s; }
.stagger-2 { transition-delay: 0.2s; }
.stagger-3 { transition-delay: 0.3s; }
.stagger-4 { transition-delay: 0.4s; }
.stagger-5 { transition-delay: 0.5s; }
.stagger-6 { transition-delay: 0.6s; }

/* JS 未加载时 2s 后自动显示（防止内容永久隐藏） */
@keyframes fade-fallback {
  to { opacity: 1; transform: translateY(0); }
}
.fade-section {
  animation: fade-fallback 0.8s ease 2s forwards;
}
.fade-section.visible {
  animation: none;
}

/* --- 渐变文字 --- */
.gradient-text {
  background: linear-gradient(135deg, var(--od-primary), var(--od-primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* --- Pill 标签 --- */
.pill {
  display: inline-block;
  padding: var(--od-space-xs) 14px;
  font-size: var(--od-text-xs);
  font-weight: 600;
  border-radius: 20px;
  letter-spacing: 0.5px;
}
.pill-cyan {
  color: var(--od-primary);
  border: 1px solid var(--od-border-glow);
  background: rgba(0, 212, 255, 0.08);
}

/* --- 等宽数字 --- */
.mono {
  font-family: var(--od-font-mono);
  font-feature-settings: 'tnum';
}

/* --- 截图占位 --- */
.screenshot-placeholder {
  background: var(--od-glass-bg);
  backdrop-filter: blur(var(--od-glass-blur));
  -webkit-backdrop-filter: blur(var(--od-glass-blur));
  border: 2px dashed var(--od-border-glow);
  border-radius: var(--od-radius-lg);
  min-height: 300px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--od-text-tertiary);
  font-family: var(--od-font-mono);
  font-size: var(--od-text-base);
  text-align: center;
  padding: var(--od-space-xl);
}

/* --- 减弱动效 --- */
@media (prefers-reduced-motion: reduce) {
  .fade-section {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .fade-section.visible {
    transition: none;
  }
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}