:root {
  /* 植物学研究手稿风格 */
  /* 主背景：浅米色纸张质感 */
  --bg: #f9f7f1;
  --panel: #fcfaf5;
  --panel-soft: #f2efe6;
  
  /* 文字色：墨灰（不是纯黑） */
  --text: #3a3832;
  --muted: #7a7870;
  
  /* 植物绿：鼠尾草绿（低饱和） */
  --accent: #5c7560;
  --accent-hover: #4a5e4b;
  --accent-light: #e8ece6;
  
  /* 辅助色：暖棕（不是蓝色/紫色） */
  --warm: #8b7355;
  --warm-soft: #f0e8dc;
  
  /* 边框和阴影：极淡 */
  --border: rgba(58, 56, 50, 0.06);
  --shadow: 0 2px 8px rgba(58, 56, 50, 0.03);
  
  /* Hero 和卡片 */
  --hero-bg: #fcfaf5;
  --list-accent: #eef2ee;
}

/* 植物学研究手稿风格背景 - 响应式适配 */
body {
  margin: 0;
  background-color: var(--bg);
  /* 桌面端：完整背景图 */
  background-image: url("../background.png"),
    /* 纸张纹理 */
    repeating-radial-gradient(circle at 50% 50%, transparent 0, transparent 2px, rgba(58, 56, 50, 0.01) 2px, rgba(58, 56, 50, 0.01) 4px);
  background-size: cover, 4px 4px;
  background-position: center, center;
  background-repeat: no-repeat;
  background-attachment: fixed, local;
}

/* 移动端优化：避免画面断层 */
@media (max-width: 720px) {
  body {
    /* 移动端使用纯色背景 + SVG 角落装饰 */
    background-image: 
      /* 角落淡色晕影 */
      radial-gradient(circle at 0% 0%, rgba(139, 115, 85, 0.03) 0%, transparent 40%),
      radial-gradient(circle at 100% 0%, rgba(139, 115, 85, 0.03) 0%, transparent 40%),
      radial-gradient(circle at 0% 100%, rgba(139, 115, 85, 0.03) 0%, transparent 40%),
      radial-gradient(circle at 100% 100%, rgba(139, 115, 85, 0.03) 0%, transparent 40%),
      /* SVG 角落植物装饰 */
      url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='400' height='600'%3E%3Cdefs%3E%3Cfilter id='blur'%3E%3CfeGaussianBlur in='SourceGraphic' stdDeviation='2'/%3E%3C/filter%3E%3C/defs%3E%3Cg opacity='0.06'%3E%3Cpath fill='%235c7560' d='M10 100 Q30 80 50 100 T80 140 Q60 160 40 140 T10 100'/%3E%3Cpath fill='%235c7560' d='M350 100 Q330 80 310 100 T280 140 Q300 160 320 140 T350 100'/%3E%3Cpath fill='%235c7560' d='M10 550 Q30 530 50 550 T80 590 Q60 610 40 590 T10 550'/%3E%3Cpath fill='%235c7560' d='M350 550 Q330 530 310 550 T280 590 Q300 610 320 590 T350 550'/%3E%3C/g%3E%3C/svg%3E");
    background-size: auto, 4px 4px, 400px 600px;
    background-position: center, center, center;
    background-attachment: scroll, local, fixed;
  }
}

* { box-sizing: border-box; }

body {
  color: var(--text);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, sans-serif;
  line-height: 1.8;
  font-size: 16px;
  letter-spacing: 0.01em;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

.wrap {
  width: min(960px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: rgba(246, 243, 238, 0.88);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 18px 0;
  align-items: center;
}

.site-title {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: "Cormorant Garamond", "Noto Serif SC", "Source Han Serif CN", serif;
  font-size: 1.9rem;
  font-weight: 600;
  color: var(--text);
  letter-spacing: -0.01em;
}

.site-title a {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: inherit;
}

.site-title a:hover {
  color: var(--accent);
}

.site-tagline {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 400;
}

.site-logo {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--border);
}

.site-tagline {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.site-nav {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

/* Hamburger 菜单按钮 */
.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  flex-direction: column;
  gap: 5px;
  z-index: 100;
  margin-left: auto;
}

.menu-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text);
  transition: all 0.3s ease;
  border-radius: 2px;
}

.menu-toggle:hover span {
  background: var(--accent);
}

.menu-toggle.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
  opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

.site-nav a {
  color: var(--text);
  font-weight: 500;
  padding: 4px 2px;
  position: relative;
}

.site-nav a:hover {
  color: var(--accent);
  text-decoration: none;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -3px;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.22s ease;
}

.site-nav a:hover::after {
  width: 100%;
}

/* 移动端导航菜单 */
.mobile-nav {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  background: rgba(251, 249, 246, 0.98);
  border-bottom: 1px solid var(--border);
  padding: 16px 24px;
  backdrop-filter: blur(10px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.mobile-nav a {
  display: block;
  padding: 12px 0;
  color: var(--text);
  font-weight: 500;
  font-size: 1rem;
  border-bottom: 1px solid rgba(47, 49, 45, 0.06);
}

.mobile-nav a:last-child {
  border-bottom: none;
}

.mobile-nav a:hover {
  color: var(--accent);
}

main.wrap {
  padding: 32px 0 48px;
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 24px;
  box-shadow: var(--shadow);
  transition: border-color 0.2s ease;
}

.card:hover {
  border-color: rgba(92, 117, 96, 0.15);
}

.hero {
  padding: 32px 28px;
  margin-bottom: 28px;
  background: var(--hero-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.hero h1 {
  font-family: "Cormorant Garamond", "Noto Serif SC", "Source Han Serif CN", serif;
  font-size: 2rem;
  font-weight: 600;
  margin: 0 0 8px;
  color: var(--text);
  letter-spacing: -0.02em;
}

.hero p {
  margin: 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.6;
}

.hero h1 {
  font-family: "Noto Serif SC", "Source Han Serif CN", "Songti SC", "SimSun", serif;
  font-size: 1.8rem;
  font-weight: 700;
  margin: 0 0 8px;
  color: var(--text);
}

.eyebrow {
  display: inline-block;
  margin-bottom: 8px;
  color: var(--warm);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
}

.grid {
  display: grid;
  gap: 16px;
  margin-bottom: 24px;
}

.three-up {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

.section-card {
  transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.section-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(47, 49, 45, 0.06);
  border-color: rgba(66, 107, 87, 0.14);
}

.section-card h2,
.post-item h2,
.post-item h3 {
  margin-top: 0;
  color: var(--text);
  font-family: "Cormorant Garamond", "Noto Serif SC", "Source Han Serif CN", serif;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.section-card h2 { font-size: 1.25rem; }
.post-item h2 { font-size: 1.15rem; }
.post-item h3 { font-size: 1.1rem; }

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.section-head h2 {
  font-family: "Cormorant Garamond", "Noto Serif SC", "Source Han Serif CN", serif;
  font-size: 1.3rem;
  font-weight: 600;
  margin: 0;
  color: var(--text);
  letter-spacing: -0.01em;
}

.post-list {
  display: grid;
  gap: 14px;
  margin-top: 16px;
}

.post-item {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  transition: all 0.2s ease;
}

.post-item:hover {
  border-color: rgba(92, 117, 96, 0.2);
  box-shadow: var(--shadow);
}

/* 第一个项目用淡色背景 */
.post-item:first-child {
  background: var(--list-accent);
}

.meta {
  color: var(--muted);
  font-size: 0.9rem;
}

.article h1 {
  margin-bottom: 12px;
  font-family: "Cormorant Garamond", "Noto Serif SC", "Source Han Serif CN", serif;
  font-size: 2rem;
  letter-spacing: -0.02em;
  font-weight: 600;
  color: var(--text);
}

.article h2,
.article h3,
.article h4,
.article h5,
.article h6 {
  font-family: "Cormorant Garamond", "Noto Serif SC", "Source Han Serif CN", serif;
  font-weight: 600;
  margin-top: 1.8em;
  color: var(--text);
  letter-spacing: -0.01em;
}

.article h2 { font-size: 1.5rem; }
.article h3 { font-size: 1.3rem; }

.prose :first-child {
  margin-top: 0;
}

.prose img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
}

.prose blockquote {
  margin: 1.2rem 0;
  padding: 1rem 1.2rem;
  background: var(--panel-soft);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  color: var(--text);
}

.prose code {
  background: var(--panel-soft);
  padding: 0.2rem 0.4rem;
  border-radius: 4px;
  font-size: 0.9em;
}

.prose pre {
  background: var(--panel-soft);
  padding: 16px;
  border-radius: 10px;
  overflow-x: auto;
  border: 1px solid var(--border);
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.tag {
  display: inline-flex;
  padding: 4px 10px;
  border-radius: 4px;
  background: var(--panel-soft);
  color: var(--accent);
  font-size: 0.8rem;
  border: 1px solid var(--border);
  font-weight: 500;
  font-family: "PingFang SC", sans-serif;
}

.tag:first-child {
  background: var(--accent-light);
  border-color: rgba(92, 117, 96, 0.12);
  color: var(--accent);
}

.site-footer {
  padding: 0 0 48px;
  color: var(--muted);
  font-size: 0.9rem;
}

@media (max-width: 720px) {
  .header-inner,
  .section-head {
    flex-direction: column;
    align-items: flex-start;
  }

  .menu-toggle {
    display: flex;
  }

  .site-nav {
    display: none;
    width: 100%;
    flex-direction: column;
    margin-top: 12px;
    gap: 0;
  }

  .site-nav.active {
    display: flex;
  }

  .site-nav a {
    font-size: 0.9rem;
    padding: 12px 0;
    border-bottom: 1px solid rgba(47, 49, 45, 0.06);
    width: 100%;
  }

  .site-nav a::after {
    display: none;
  }

  .site-nav a:hover {
    background: var(--panel-soft);
  }

  .card,
  .hero {
    padding: 20px;
  }

  .article h1 {
    font-size: 1.5rem;
  }

  .site-title {
    font-size: 1.4rem;
  }

  .site-logo {
    width: 40px;
    height: 40px;
  }
  
  .site-nav a {
    font-size: 0.9rem;
    padding: 10px 0;
  }
}