/* ===== 全局样式 ===== */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  background-color: #1A1A2E;
  color: #E8E8F0;
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

/* ===== 导航栏滚动效果 ===== */
#navbar {
  background: transparent;
}

#navbar.scrolled {
  background: rgba(26, 26, 46, 0.85);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

/* ===== 网格背景 ===== */
.grid-bg {
  background-image:
    linear-gradient(rgba(155, 143, 224, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(155, 143, 224, 0.07) 1px, transparent 1px);
  background-size: 80px 80px;
}

/* ===== 渐变文字 ===== */
.text-gradient {
  background: linear-gradient(135deg, #A594F9 0%, #7C6FCD 60%, #5A4FB0 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ===== 动画 ===== */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in {
  animation: fadeIn 1s ease-out forwards;
}

.animate-slide-up {
  animation: slideUp 0.9s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.delay-100 { animation-delay: 0.1s; opacity: 0; }
.delay-200 { animation-delay: 0.2s; opacity: 0; }
.delay-300 { animation-delay: 0.35s; opacity: 0; }
.delay-400 { animation-delay: 0.5s; opacity: 0; }

/* ===== 步骤卡片 ===== */
.step-card {
  transition: transform 0.3s ease, border-color 0.3s ease, background 0.3s ease;
}

/* ===== 下载卡片 ===== */
.download-card {
  transition: transform 0.3s ease, border-color 0.3s ease;
}

.download-card:hover {
  transform: translateY(-3px);
}

/* ===== 截图轮播 ===== */
.screenshots-container {
  position: relative;
}

.screenshots-track {
  will-change: transform;
}

/* ===== FAQ 手风琴 ===== */
.faq-item {
  transition: border-color 0.3s ease;
}

.faq-btn {
  cursor: pointer;
  background: none;
  border: none;
  outline: none;
}

.faq-btn:focus {
  outline: none;
}

.faq-content {
  transition: all 0.3s ease;
}

.faq-btn .fa-chevron-down {
  transition: transform 0.3s ease;
}

.faq-item.open .faq-btn .fa-chevron-down {
  transform: rotate(180deg);
}

/* ===== 统计数字动画 ===== */
.stat-item {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.stat-item.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 滚动显示动画 ===== */
.scroll-reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.8s cubic-bezier(0.16, 1, 0.3, 1), transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

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

/* ===== 轮播指示点 ===== */
.dot {
  cursor: pointer;
  transition: all 0.3s ease;
  border: none;
  outline: none;
}

.dot.active {
  background-color: #7C6FCD;
  width: 20px;
  border-radius: 4px;
}

/* ===== 自定义滚动条 ===== */
::-webkit-scrollbar {
  width: 5px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: #3A3A5C;
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: #7C6FCD;
}

/* ===== 选中文字颜色 ===== */
::selection {
  background: rgba(124, 111, 205, 0.25);
  color: white;
}

/* ===== 光晕动画 ===== */
@keyframes glow-pulse {
  0%, 100% { opacity: 0.4; transform: scale(1); }
  50% { opacity: 0.7; transform: scale(1.04); }
}

.glow-animate {
  animation: glow-pulse 5s ease-in-out infinite;
}