/* === 字体 === */
@import url('https://fonts.googleapis.com/css2?family=Orbitron:wght@500;700&display=swap');

html, body {
  margin: 0;
  padding: 0;
  overscroll-behavior: none;
  /* 亮色背景：改为浅色渐变或纯白 */
  background: #bae8db; 
  overflow-x: hidden;
}

canvas#bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
  background: transparent;
}

body * {
  position: relative;
  z-index: 1;
}

body {
  font-family: 'Orbitron', 'Smiley Sans', 'Source Han Sans SC', sans-serif;
  /* 文字颜色改为深色 */
  color: #333; 
  text-align: center;
}

/* === 毛玻璃卡片 (改为浅色卡片) === */
.card {
  /* 背景改为白色，透明度降低或移除 */
  background: rgba(255, 255, 255, 0.95); 
  /* 移除蓝色边框 */
  border: 1px solid #e0e0e0; 
  /* 柔和的浅色阴影 */
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08); 
  backdrop-filter: blur(12px);
  border-radius: 18px;
  padding: 26px;
  width: 85%;
  max-width: 760px;
  margin: 40px auto;
  transition: all 0.4s ease;
}
.card:hover {
  transform: translateY(-4px);
  /* 柔和的悬停阴影 */
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.12); 
}

/* === Logo & Hero === */
.logo {
  width: 120px;
  margin-bottom: 10px;
  /* 移除蓝色 Logo 阴影，保持新 Logo 颜色 */
  filter: none; 
}

h1 {
  font-size: 2.8rem;
  /* 主标题颜色改为深色，可以使用绿色调渐变 */
  background: linear-gradient(90deg, #4CAF50, #8BC34A); 
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 10px;
}

.subtitle {
  font-size: 1.1rem;
  /* 副标题使用中等深度的颜色 */
  color: #555; 
  opacity: 1;
  margin-bottom: 26px;
}

/* === 按钮 === */
.button-group {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 14px;
}

.btn {
  text-decoration: none;
  padding: 12px 26px;
  border-radius: 8px;
  font-size: 1rem;
  letter-spacing: 0.5px;
  transition: 0.25s ease;
  /* 普通按钮改为白色背景，深色边框和文字 */
  border: 1px solid #ccc;
  color: #555;
  background: #fff;
}
.btn:hover {
  /* 悬停阴影改为柔和的浅色 */
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.1); 
  transform: translateY(-2px);
}

.btn.primary {
  /* Primary 按钮改为绿色主题色 */
  background: linear-gradient(90deg, #4CAF50, #689F38); 
  color: white; /* 保持白色文字 */
  font-weight: bold;
  /* Primary 按钮使用绿色阴影 */
  box-shadow: 0 4px 15px rgba(76, 175, 80, 0.4); 
  border: none;
}
.btn.primary:hover {
  /* 悬停时更亮的绿色阴影 */
  box-shadow: 0 6px 20px rgba(76, 175, 80, 0.6); 
}

/* === Features === */
.features h2,
.dev h2 {
  font-size: 1.6rem;
  margin-bottom: 18px;
  /* 标题颜色使用主题绿 */
  color: #4CAF50; 
}

.feature-list {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 22px;
}

.feature-item {
  width: 180px;
  opacity: 1; /* 保持高透明度 */
  color: #555;
  transition: 0.3s;
}
.feature-item:hover {
  transform: scale(1.08);
  /* 悬停时添加一点点绿色阴影 */
  text-shadow: 0 0 5px rgba(76, 175, 80, 0.3);
}
.feature-item .icon {
  font-size: 2rem;
  /* Icon 颜色使用主题绿 */
  color: #4CAF50; 
  margin-bottom: 8px;
}

/* === Developer Section === */
.dev-link {
  /* 链接颜色使用主题绿 */
  color: #4CAF50; 
  text-decoration: none;
  font-weight: 500;
  transition: 0.3s;
}
.dev-link:hover {
  /* 悬停时绿色阴影 */
  text-shadow: 0 0 8px #4CAF50; 
}

/* === Footer === */
footer {
  margin-top: 50px;
  font-size: 0.85rem;
  opacity: 1;
  color: #777; /* 底部文字改为中性色 */
  text-shadow: none;
}

/* === 动画 === */
.fade-in {
  opacity: 0;
  transform: translateY(15px);
  animation: fadeUp 1.2s ease forwards;
}
@keyframes fadeUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* === 导航栏 === */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  padding: 1rem 2rem;
  z-index: 100;
  /* 导航栏背景改为白色 */
  background: rgba(255, 255, 255, 0.95); 
  backdrop-filter: blur(10px);
  /* 边框改为浅灰色 */
  border-bottom: 1px solid #e0e0e0; 
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05); /* 柔和阴影 */
}

.nav-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: 'Orbitron', sans-serif;
  font-weight: 700;
  color: #333; /* 导航栏文字改为深色 */
}

.small-logo {
  width: 32px;
  height: 32px;
}

.language-switcher {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  /* 切换器背景改为透明或极浅色 */
  background: rgba(0, 0, 0, 0.03); 
  padding: 0.5rem 1rem;
  border-radius: 25px;
  backdrop-filter: blur(5px);
}

.lang-btn {
  background: none;
  border: none;
  color: #555; /* 按钮文字改为深色 */
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  border-radius: 15px;
  transition: all 0.3s ease;
  font-family: inherit;
}

.lang-btn:hover {
  background: rgba(0, 0, 0, 0.08); /* 悬停浅色背景 */
}

.lang-btn.active {
  background: #e0e0e0; /* 激活时浅灰色背景 */
  font-weight: bold;
}

.lang-separator {
  color: #ccc; /* 分隔符改为浅灰色 */
}

.card {
  margin-top: 100px; /* 增加边距以适应固定导航栏 */
}