:root {
  --bg: #f6f8fb; /* cooler light blue-gray */
  --panel: #ffffff;
  --text: #2a1e16;
  --muted: #6b5e55;
  --brand: #cc6c00; /* warm accent */
  --brand-2: #ffb347; /* warm accent 2 */
  --border: #e6dfd6;
  --header-h: 64px; /* approximate header height */
  --masthead-image: url('./images/7.png'); /* replace with your image URL */
}

/* 全局图片渲染优化 */
* {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, 
[style*="background-image"] {
  image-rendering: auto; /* 现代浏览器默认渲染，适合SVG */
  image-rendering: -webkit-optimize-contrast;
}

/* 防止缩放时的布局抖动 */
.hero {
  transform: translateZ(0);
  -webkit-transform: translateZ(0);
  will-change: transform;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
}

.container {
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Narrower content after hero */
.content-narrow .container {
  max-width: 760px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(180deg, rgba(255,255,255,0.92), rgba(255,255,255,0.85));
  backdrop-filter: saturate(140%) blur(8px);
  -webkit-backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
}
.brand {
  text-decoration: none;
  color: var(--text);
  font-weight: 700; /* match title weight */
  letter-spacing: 0.2px;
}
.menu-toggle {
  display: none;
  background: transparent;
  border: none;
  border-radius: 8px;
  color: var(--text);
  padding: 8px 10px;
}
.site-nav a {
  color: var(--text);
  text-decoration: none;
  margin-left: 18px;
  padding: 8px 10px;
  border-radius: 8px;
  font-weight: 700; /* align with title styling */
}
.site-nav a:hover { background: transparent; }

.hero {
  position: relative;
  padding: 100px 0 140px;
  border-bottom: 1px solid var(--border);
  min-height: 420px;
}
.hero::before {
  content: "";
  position: absolute;
  left: 0; 
  right: 0; 
  top: 0; /* 从顶部开始，完全覆盖 */
  bottom: 0; /* 到底部 */
  z-index: 15; /* 图片浮在hero card上方 */
  background-color: var(--bg); /* 与页面背景一致，避免明显色块 */
  background-image: var(--masthead-image);
  background-size: contain; /* 不裁剪，整张图片完整显示 */
  background-position: center center; /* 居中显示整张图片 */
  background-repeat: no-repeat;
  background-attachment: scroll; /* 防止背景固定导致的缩放问题 */
  /* SVG图片渲染优化 */
  image-rendering: auto; /* SVG使用默认渲染 */
  image-rendering: -webkit-optimize-contrast;
  /* 确保图片清晰度和稳定性 */
  transform: translateZ(0);
  backface-visibility: hidden;
  will-change: auto; /* 优化渲染性能 */
  /* 防止缩放时的重绘问题 */
  contain: layout style paint;
  /* SVG特殊处理 */
  background-origin: border-box;
  background-clip: border-box;
}
.hero > .container { 
  position: relative; 
  z-index: 5; /* 确保容器在背景图片上方 */
}
.kicker {
  color: #000000;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin: 0 0 10px;
  text-align: left;
  padding-left: 0;
}
h1 { 
  font-size: 42px; 
  line-height: 1.15; 
  margin: 0 0 10px; 
  color: #000000;
  text-align: left;
  padding-left: 0;
}
h2 { 
  font-size: 18px; 
  font-weight: 600; 
  color: #000000; 
  margin: 0 0 10px; 
  text-align: left;
  padding-left: 0;
}
h3 { font-size: 28px; margin: 0 0 12px; }
h4 { font-size: 20px; margin: 20px 0 6px; }
h5 { font-size: 16px; margin: 16px 0 6px; color: var(--brand); }

.hero-card {
  position: relative;
  display: inline-block;
  padding: 28px 28px 40px 28px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.9); /* 半透明白色背景，让图片透过 */
  border: 0;
  overflow: hidden;
  z-index: 10; /* 确保hero card在图片上方 */
  backdrop-filter: blur(5px); /* 添加模糊效果 */
  -webkit-backdrop-filter: blur(5px);
}
.hero-card::before { content: none; }
.hero-badge {
  position: absolute;
  right: 12px;
  bottom: 10px;
  background: #fefefe;
  color: #5a3b14;
  border: 1px solid rgba(90,59,20,0.15);
  border-radius: 10px;
  font-weight: 700;
  padding: 6px 10px;
  font-size: 12px;
}

.hero-cofun {
  position: absolute;
  left: 4px;
  bottom: 4px;
  width: 180px;
  height: auto;
  z-index: 1;
}

.btn {
  display: inline-block;
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 14px;
  text-decoration: none;
  margin-right: 10px;
}
.btn.primary {
  background: linear-gradient(90deg, var(--brand), var(--brand-2));
  border-color: transparent;
  color: #2a1e16;
  font-weight: 700;
}

.section { padding: 40px 0; }
.section + .section { border-top: none; }
.dates { list-style: none; padding: 0; margin: 0; }
.dates li { padding: 6px 0; }
.note { color: var(--muted); }

.grid.two-col {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px 24px;
}

.refs { padding-left: 18px; }
.bibtex {
  background: #fffefb;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px;
  overflow: auto;
}

/* Code / pre blocks: allow wrapping to avoid horizontal overflow */
pre {
  white-space: pre-wrap;
  word-wrap: break-word;
  overflow-x: auto;
  padding: 12px 14px;
  border-radius: 8px;
  background: #fffefb;
  border: 1px solid var(--border);
}

.site-footer {
  border-top: none;
  padding: 24px 0 60px;
  color: var(--muted);
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.footer-copy { margin: 0; }
.back-to-top {
  display: inline-block;
  margin-top: 10px;
  color: var(--brand);
  text-decoration: none;
}

/* 响应式图片优化 - 始终自适应铺满（cover） */
@media (max-width: 1200px) {
  .hero::before {
    background-position: center center;
  }
}

@media (max-width: 860px) {
  .menu-toggle { display: inline-block; }
  .site-nav { display: none; position: absolute; right: 20px; top: 56px; background: transparent; padding: 10px; border: none; border-radius: 10px; }
  .site-nav.open { display: block; }
  .site-nav a { display: block; margin: 6px 0; }
  h1 { font-size: 34px; }
  .grid.two-col { grid-template-columns: 1fr; }
  .hero-cofun { width: 130px; left: 6px; bottom: 6px; }
}

@media (max-width: 480px) {
}

html { scroll-behavior: smooth; }