/* ================= 全局重置与基础样式 ================= */
* { margin: 0; padding: 0; box-sizing: border-box; }
body { 
    font-family: 'PingFang SC', sans-serif; 
    background-color: #0a0a0a; 
    color: #fff; 
    overflow-x: hidden; 
    scroll-behavior: smooth; 
}


/* ================= 全局悬浮导航栏 ================= */
/* 全局悬浮导航栏 - 默认样式（滚动后生效：深色底色+毛玻璃） */
nav {
    position: fixed; top: 0; left: 0; width: 100%; z-index: 1000;
    display: flex; justify-content: space-between; align-items: center; padding: 20px 50px;
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(10px);
    opacity: 1; 
    transition: all 0.5s ease;
    pointer-events: auto; 
}
nav.visible { opacity: 1; pointer-events: auto; }

/* 新增：第一层专属样式（透明底色 + 黑色字体） */
nav.nav-home {
    background: transparent !important;
    backdrop-filter: none !important;
}
nav.nav-home .nav-links a {
    color: #000 !important;
}
nav.nav-home .nav-links a:hover {
    color: #222 !important;
}

/* 原有导航链接样式（滚动后恢复） */
.nav-logo {
    display: flex; align-items: center; text-decoration: none; color: #fff;
    transition: filter 0.3s ease;
}
.nav-logo:hover { filter: drop-shadow(0 0 8px rgba(74, 222, 128, 0.6)); }
.logo-img { height: 35px; width: auto; margin-right: 10px; }
.logo-text { font-size: 1.2rem; font-weight: bold; letter-spacing: 2px; }
.nav-links a { color: #ccc; text-decoration: none; margin-left: 30px; font-size: 0.9rem; transition: 0.3s; }
.nav-links a:hover { color: #4ade80; }
nav.visible { opacity: 1; pointer-events: auto; }

/* Logo 区域样式 */
.nav-logo {
    display: flex; align-items: center; text-decoration: none; color: #fff;
    transition: filter 0.3s ease;
}
.nav-logo:hover { filter: drop-shadow(0 0 8px rgba(74, 222, 128, 0.6)); } /* 悬停发光效果 */
.logo-img { height: 35px; width: auto; margin-right: 10px; }
.logo-text { font-size: 1.2rem; font-weight: bold; letter-spacing: 2px; }

/* 导航链接样式 */
.nav-links a { color: #ccc; text-decoration: none; margin-left: 30px; font-size: 0.9rem; transition: 0.3s; }
.nav-links a:hover { color: #4ade80; }

/* ================= 通用区块样式 ================= */
section { 
    width: 100%; min-height: 100vh; 
    display: flex; flex-direction: column; justify-content: center; align-items: center; text-align: center; 
    padding: 100px 20px; position: relative; 
}
h1 { font-size: 3.5rem; margin-bottom: 20px; letter-spacing: 5px; }
p.subtitle { font-size: 1.2rem; color: #aaa; max-width: 800px; line-height: 1.8; margin-bottom: 40px; }
.btn-enter { 
    padding: 15px 40px; border: 1px solid #fff; background: transparent; color: #fff; 
    font-size: 1rem; cursor: pointer; transition: 0.3s; text-decoration: none; 
}
.btn-enter:hover { background: #fff; color: #000; }

/* ================= 第一层：作品名页 ================= */
#intro-page { background: radial-gradient(circle at center, #1a1a1a 0%, #000 100%); }
.breathing-dot { 
    width: 10px; height: 10px; background: #4ade80; border-radius: 50%; margin-top: 30px; 
    animation: breathe 2s infinite; 
}
@keyframes breathe { 
    0%, 100% { opacity: 0.3; transform: scale(1); } 
    50% { opacity: 1; transform: scale(1.5); } 
}

/* ================= 第二层：视频引出页 ================= */
#video-page { background: #000; padding-bottom: 50px; }
.video-container { 
    width: 80%; max-width: 1000px; aspect-ratio: 16/9; background: #222; 
    border-radius: 8px; overflow: hidden; margin-bottom: 30px; position: relative;
}
video { width: 100%; height: 100%; object-fit: cover; }
.scroll-hint { 
    position: absolute; bottom: 30px; animation: bounce 2s infinite; 
    cursor: pointer; font-size: 0.9rem; color: #aaa; 
}
@keyframes bounce { 
    0%, 100% { transform: translateY(0); } 
    50% { transform: translateY(10px); } 
}

/* ================= 第三层：3D交互体验页 ================= */
#interactive-page { background: linear-gradient(to bottom, #0f172a, #1e293b); padding-top: 120px;}
.game-area { 
    width: 80%; max-width: 900px; height: 450px; 
    background-color: #352a1b; 
    background-size: cover; border-radius: 12px; position: relative; overflow: hidden; 
    border: 2px solid #334155; cursor: crosshair;
}
.garbage-item { 
    position: absolute; font-size: 2.5rem; transition: all 0.5s ease; cursor: pointer; user-select: none;
}
.garbage-item:hover { transform: scale(1.2); filter: drop-shadow(0 0 10px rgba(255,255,255,0.5)); }
.progress-bar-container { 
    width: 80%; max-width: 900px; height: 10px; background: #334155; 
    border-radius: 5px; margin-top: 30px; overflow: hidden;
}
.progress-bar-fill { height: 100%; width: 0%; background: #4ade80; transition: width 0.5s ease; }
.status-text { margin-top: 15px; font-size: 1rem; color: #94a3b8; }

/* ================= 第四层：科普详情页 ================= */
#science-page { background: #f8fafc; color: #1e293b; padding-top: 120px; align-items: stretch;}
.cards-container { 
    display: flex; gap: 30px; width: 90%; max-width: 1200px; margin: 0 auto; 
    flex-wrap: wrap; justify-content: center;
}
.card { 
    flex: 1; min-width: 300px; background: #fff; border-radius: 12px; padding: 40px 30px; text-align: left; 
    box-shadow: 0 4px 6px rgba(0,0,0,0.05); transition: transform 0.3s; border-top: 5px solid #ccc;
}
.card:hover { transform: translateY(-5px); }
.card.inorganic { border-top-color: #64748b; }
.card.organic { border-top-color: #f59e0b; }
.card.bio { border-top-color: #ef4444; }
.card h3 { font-size: 1.5rem; margin-bottom: 15px; }
.card .slogan { font-size: 1rem; color: #64748b; margin-bottom: 20px; font-style: italic; }
.card ul { list-style-type: disc; padding-left: 20px; line-height: 1.8; font-size: 0.95rem; color: #334155; }
.source-tag { 
    display: inline-block; margin-top: 20px; font-size: 0.75rem; color: #94a3b8; 
    background: #f1f5f9; padding: 4px 8px; border-radius: 4px; 
}

.bottom-action { margin-top: 60px; margin-bottom: 40px; }
.btn-secondary { 
    padding: 15px 30px; border: 1px solid #1e293b; background: transparent; color: #1e293b; 
    font-size: 1rem; cursor: pointer; transition: 0.3s; text-decoration: none; margin: 0 10px;
}
.btn-secondary:hover { background: #1e293b; color: #fff; }
/* 页面左上角 Logo 容器 */
.page-logo {
    position: fixed; /* 固定定位，不会随页面滚动 */
    top: 20px;       /* 距离页面顶部的距离 */
    left: 20px;      /* 距离页面左侧的距离 */
    display: flex;
    align-items: center;
    gap: 10px;       /* 图片和文字之间的间距 */
    z-index: 9999;   /* 层级设高一点，确保不会被其他内容挡住 */
    color: #fff;
    text-decoration: none;
    pointer-events: none; /* 可选：让 Logo 不影响点击，背景内容依然可交互 */
}

/* Logo 图片样式 */
.page-logo-img {
    height: 35px;    /* 和你原来的导航栏 Logo 保持一样的高度 */
    width: auto;
    display: block;
    object-fit: contain;
}

/* Logo 文字样式 */
.page-logo-text {
    font-size: 1.2rem;
    font-weight: bold;
    letter-spacing: 2px;
    white-space: nowrap; /* 防止文字换行 */
}

/* 卡片详情按钮 */
.btn-detail {
    display: inline-block;
    margin-top: 16px;
    padding: 8px 18px;
    background-color: #1e293b;
    color: #fff;
    text-decoration: none;
    font-size: 0.9rem;
    border-radius: 4px;
    transition: 0.3s;
}
.btn-detail:hover {
    background-color: #4ade80;
    color: #000;
}
/* 仅第一层导航文字变黑 */
nav.nav-first .nav-links a {
    color: #000;
}
nav.nav-first .nav-links a:hover {
    color: #222;
}
:root {
  --green-deep: #1b3b2b;
  --white: #ffffff;
  --max-width: 1200px;
  --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
}
html {
  font-size:16px;
}
body {
  font-family:var(--font-sans);
}
.footer {
  background:var(--green-deep);
  color:rgba(255,255,255,0.8);
  padding:60px 32px 30px;
}
.footer-inner {
  max-width:var(--max-width);
  margin:0 auto;
  display:grid;
  grid-template-columns:repeat(auto-fit, minmax(220px,1fr));
  gap:40px;
}
.footer h4 {
  color:#fff;
  margin-bottom:14px;
}
.footer p,.footer li {
  font-size:0.85rem;
  color:rgba(255,255,255,0.65);
}
.footer-bottom {
  text-align:center;
  padding-top:30px;
  margin-top:30px;
  border-top:1px solid rgba(255,255,255,0.15);
  font-size:0.8rem;
  color:rgba(255,255,255,0.5);
}
@media (max-width:900px) {
  .footer {
    padding: 60px 20px 30px;
  }
  .footer-inner {
    gap: 30px;
  }
}