/* ===========================================================
   雪中漫步 · 个人博客  —  暗色雪夜主题（默认）
   配色：深蓝夜空 + 冰雪蓝点缀 + 暖白文字
   头部=巴黎夜晚街景 / 身体区=夜景背景 / 尾部=夜景背景
   亮色主题（[data-theme="light"]）仅切换身体与尾部为浅色渐变，头部保持夜景
   =========================================================== */

:root {
  --bg-deep:   #0a0f1c;
  --bg-2:      #121a2e;
  --panel:     rgba(255, 255, 255, 0.05);
  --panel-2:   rgba(255, 255, 255, 0.09);
  --border:    rgba(207, 232, 255, 0.14);
  --text:      #e8eef6;
  --text-dim:  #9fb2cc;
  --accent:    #acd4ff;
  --accent-2:  #e8f4ff;
  --shadow:    0 10px 30px rgba(0, 0, 0, 0.45);
  --serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", "Source Han Serif SC", serif;
  --sans:  "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, sans-serif;
}

/* 亮色主题：身体/尾部转浅色渐变，头部仍为夜景 */
[data-theme="light"] {
  --bg-deep:  #dfe8f5;
  --bg-2:     #f4f8fd;
  --panel:    rgba(20, 35, 65, 0.04);
  --panel-2:  rgba(20, 35, 65, 0.08);
  --border:   rgba(30, 60, 110, 0.16);
  --text:     #1b2742;
  --text-dim: #5a6b86;
  --accent:   #2f6fd0;
  --accent-2: #184d96;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--text);
  /* 暗色默认：夜景身体背景 + 深蓝压暗遮罩，保证正文可读 */
  background:
    linear-gradient(180deg, rgba(8, 12, 24, 0.84) 0%, rgba(8, 12, 24, 0.92) 100%),
    url("../images/body-bg.jpg") center / cover fixed;
  background-attachment: fixed;
  line-height: 1.85;
  -webkit-font-smoothing: antialiased;
  transition: background-color .3s, color .3s;
}
[data-theme="light"] body {
  background:
    radial-gradient(1200px 600px at 50% -10%, #ffffff 0%, transparent 60%),
    linear-gradient(180deg, var(--bg-deep) 0%, var(--bg-2) 100%);
}

a { color: var(--accent); text-decoration: none; transition: color .2s; }
a:hover { color: var(--accent-2); }

/* ---------- 头部横幅（巴黎夜晚街景） ---------- */
.banner {
  position: relative;
  min-height: 62vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  background: url("../images/header-banner.jpg") center / cover no-repeat fixed;
  overflow: hidden;
}
.banner::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg,
    rgba(10, 15, 28, 0.32) 0%,
    rgba(10, 15, 28, 0.50) 50%,
    rgba(10, 15, 28, 0.90) 100%);
}
.banner > * { position: relative; z-index: 1; }

.site-brand {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 10px;
}
.site-brand img { width: 46px; height: 46px; filter: drop-shadow(0 2px 6px rgba(0,0,0,.5)); }
.site-title {
  font-family: var(--serif);
  font-size: clamp(2.4rem, 6vw, 4rem);
  letter-spacing: .35em;
  margin: 0;
  text-indent: .35em;
  color: #fff;
  text-shadow: 0 4px 24px rgba(0, 0, 0, .6);
  font-weight: 600;
}
.site-subtitle {
  max-width: 640px;
  margin: 14px auto 0;
  padding: 0 20px;
  color: #dbe6f5;
  font-size: 1rem;
  text-shadow: 0 2px 12px rgba(0, 0, 0, .7);
}
[data-theme="light"] .site-subtitle { color: #f3ece3; }

/* ---------- 导航 ---------- */
.nav {
  margin-top: 30px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 4px;
}
.nav a {
  color: #e8eef6;
  padding: 8px 16px;
  border-radius: 999px;
  font-size: .95rem;
  letter-spacing: .08em;
  border: 1px solid transparent;
  transition: all .25s;
}
.nav a:hover {
  background: var(--panel-2);
  border-color: var(--border);
  color: #fff;
}
[data-theme="light"] .nav a { color: var(--text-dim); }
[data-theme="light"] .nav a:hover { background: var(--panel-2); color: var(--text); border-color: var(--border); }

/* ---------- 主体 ---------- */
.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 56px 20px 40px;
}

.section-head {
  display: flex;
  align-items: center;
  gap: 14px;
  margin: 0 0 28px;
  color: var(--text-dim);
  font-family: var(--serif);
  letter-spacing: .2em;
}
.section-head::before,
.section-head::after {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border), transparent);
}

/* ---------- 文章卡片 ---------- */
.post-list { display: grid; gap: 26px; }

.post {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
  backdrop-filter: blur(8px);
  box-shadow: var(--shadow);
  transition: transform .3s ease, border-color .3s ease;
}
.post:hover { transform: translateY(-4px); border-color: rgba(172, 212, 255, .4); }
[data-theme="light"] .post:hover { border-color: rgba(47, 111, 208, .45); }

.post-feature {
  display: block;
  width: 100%;
  height: 240px;
  overflow: hidden;
}
.post-feature img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .6s ease;
}
.post:hover .post-feature img { transform: scale(1.06); }

.post-body { padding: 22px 26px 26px; }
.post-title {
  font-family: var(--serif);
  font-size: 1.5rem;
  margin: 0 0 6px;
  color: var(--text);
  letter-spacing: .03em;
}
.post-title:hover { color: var(--accent-2); }
.post-meta {
  font-size: .82rem;
  color: var(--text-dim);
  letter-spacing: .05em;
  margin-bottom: 12px;
}
.post-meta .dot { margin: 0 8px; opacity: .5; }
.post-excerpt { color: #cdd9ea; margin: 0; font-size: .98rem; }
[data-theme="light"] .post-excerpt { color: var(--text-dim); }

/* 纯文字卡片（无配图） */
.post.text-only .post-body { padding-top: 26px; }

/* ---------- 分页 ---------- */
.pager {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 40px;
}
.pager a, .pager span {
  min-width: 40px;
  height: 40px;
  padding: 0 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text-dim);
  font-size: .9rem;
}
.pager .current { background: var(--panel-2); color: #fff; border-color: rgba(172,212,255,.4); }
[data-theme="light"] .pager .current { color: var(--text); border-color: rgba(47,111,208,.5); }

/* ---------- 底部（夜景背景） ---------- */
.footer {
  margin-top: 60px;
  border-top: 1px solid var(--border);
  background:
    linear-gradient(180deg, rgba(8, 12, 24, 0.82) 0%, rgba(8, 12, 24, 0.96) 100%),
    url("../images/footer-bg.jpg") center bottom / cover no-repeat;
}
[data-theme="light"] .footer {
  background: linear-gradient(180deg, transparent, rgba(20, 35, 65, 0.05));
}
.footer-widgets {
  max-width: 980px;
  margin: 0 auto;
  padding: 46px 20px 10px;
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 40px;
}
.widget h3 {
  font-family: var(--serif);
  font-size: 1.05rem;
  letter-spacing: .15em;
  color: var(--text);
  margin: 0 0 18px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}
.recent-comments { list-style: none; margin: 0; padding: 0; }
.recent-comments li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  margin-bottom: 16px;
  font-size: .9rem;
}
.recent-comments img { width: 38px; height: 38px; border-radius: 50%; flex: 0 0 auto; }
.recent-comments a { color: var(--text); line-height: 1.5; }

.tag-cloud { display: flex; flex-wrap: wrap; gap: 10px; }
.tag-cloud a {
  font-size: .85rem;
  padding: 5px 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text-dim);
}
.tag-cloud a:hover { color: #fff; border-color: rgba(172,212,255,.45); }
[data-theme="light"] .tag-cloud a:hover { color: var(--accent); border-color: rgba(47,111,208,.5); }

.message-wall { display: flex; flex-wrap: wrap; gap: 12px; }
.message-wall img { width: 44px; height: 44px; border-radius: 50%; border: 1px solid var(--border); }

.footer-copy {
  text-align: center;
  color: var(--text-dim);
  font-size: .82rem;
  padding: 26px 20px 40px;
  letter-spacing: .04em;
}
.footer-copy a { color: var(--text-dim); }

/* ---------- 飘雪层 ---------- */
.snow-container {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
}

/* ---------- 文章详情页 ---------- */
.post-detail { max-width: 760px; margin: 0 auto; padding: 90px 20px 40px; }
.post-detail .back { display: inline-block; margin-bottom: 26px; color: var(--text-dim); }
.post-detail h1 {
  font-family: var(--serif);
  font-size: 2.2rem;
  color: var(--text);
  margin: 0 0 12px;
  letter-spacing: .04em;
}
.post-detail .cover { width: 100%; border-radius: 14px; margin: 22px 0; box-shadow: var(--shadow); }
.post-detail p { color: #d3deec; font-size: 1.05rem; margin: 0 0 1.2em; }
[data-theme="light"] .post-detail p { color: var(--text); }

/* ---------- 吸顶导航（默认暗色毛玻璃） ---------- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(10, 15, 28, .72);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
[data-theme="light"] .navbar { background: rgba(244, 248, 253, .82); }
.navbar-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 10px 20px;
  display: flex;
  align-items: center;
  gap: 16px;
}
.brand-mini {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text);
  font-family: var(--serif);
  letter-spacing: .12em;
  white-space: nowrap;
}
.brand-mini img { width: 26px; height: 26px; }
.menu {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  margin: 0;
  padding: 0;
  flex: 1;
}
.menu a {
  display: block;
  padding: 7px 13px;
  border-radius: 999px;
  color: var(--text-dim);
  font-size: .9rem;
  letter-spacing: .06em;
  transition: all .2s;
}
.menu a:hover { color: var(--text); background: var(--panel-2); }
.theme-toggle {
  flex: 0 0 auto;
  min-width: 44px;
  height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text-dim);
  cursor: pointer;
  font-size: .85rem;
  letter-spacing: .1em;
  transition: all .2s;
}
.theme-toggle:hover { color: var(--text); border-color: rgba(172, 212, 255, .45); }
[data-theme="light"] .theme-toggle:hover { border-color: rgba(47, 111, 208, .5); }

/* ---------- 搜索框 ---------- */
.search-wrap { margin: 0 0 26px; }
.search-wrap input {
  width: 100%;
  padding: 13px 18px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  font-size: .98rem;
  outline: none;
  transition: border-color .2s, background .2s;
}
.search-wrap input::placeholder { color: var(--text-dim); }
.search-wrap input:focus { border-color: rgba(172, 212, 255, .5); background: var(--panel-2); }
[data-theme="light"] .search-wrap input:focus { border-color: rgba(47, 111, 208, .5); }

/* ---------- 返回顶部 ---------- */
.to-top {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 60;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  cursor: pointer;
  font-size: .82rem;
  letter-spacing: .05em;
  backdrop-filter: blur(8px);
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity .3s, transform .3s;
}
.to-top.show { opacity: 1; transform: translateY(0); pointer-events: auto; }
.to-top:hover { border-color: rgba(172, 212, 255, .5); color: var(--accent-2); }
[data-theme="light"] .to-top:hover { border-color: rgba(47, 111, 208, .5); }

/* ---------- 文章详情：上下篇导航 ---------- */
.post-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 40px;
  padding-top: 22px;
  border-top: 1px solid var(--border);
}
.post-nav a { color: var(--text-dim); font-size: .92rem; max-width: 48%; }
.post-nav a:hover { color: var(--accent-2); }
.post-nav .next { text-align: right; }

/* ---------- 分类/标签筛选 ---------- */
.filters { margin: 0 0 22px; display: grid; gap: 10px; }
.filter-row { display: flex; align-items: center; flex-wrap: wrap; gap: 8px; }
.filter-label {
  color: var(--text-dim);
  font-size: .82rem;
  letter-spacing: .1em;
  margin-right: 4px;
  flex: 0 0 auto;
}
.chip {
  cursor: pointer;
  font-size: .85rem;
  padding: 5px 13px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text-dim);
  transition: all .2s;
  font-family: inherit;
}
.chip:hover { color: var(--text); border-color: rgba(172, 212, 255, .45); }
[data-theme="light"] .chip:hover { border-color: rgba(47, 111, 208, .5); }
.chip.active { background: var(--panel-2); color: #fff; border-color: rgba(172, 212, 255, .55); }
[data-theme="light"] .chip.active { background: var(--accent); color: #fff; border-color: var(--accent); }

.mini-tags { margin-top: 12px; display: flex; flex-wrap: wrap; gap: 6px; }
.mini-tag {
  font-size: .74rem;
  color: var(--text-dim);
  padding: 2px 9px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--panel);
}

/* ---------- 时光轴 ---------- */
.timeline { max-width: 720px; margin: 0 auto; padding: 8px 0 10px; }
.tl-group { margin-bottom: 30px; }
.tl-month {
  font-family: var(--serif);
  font-size: 1.15rem;
  color: var(--accent);
  letter-spacing: .12em;
  margin-bottom: 14px;
  padding-left: 18px;
  border-left: 3px solid rgba(172, 212, 255, .5);
}
.tl-items { list-style: none; margin: 0; padding: 0; }
.tl-items li {
  display: flex;
  align-items: baseline;
  gap: 14px;
  padding: 9px 0;
  border-bottom: 1px dashed var(--border);
}
.tl-date { color: var(--text-dim); font-size: .85rem; flex: 0 0 56px; text-align: right; }
.tl-items a { color: var(--text); font-size: 1rem; }
.tl-items a:hover { color: var(--accent-2); }

/* ---------- 关于/个人档 ---------- */
.about { max-width: 720px; margin: 0 auto; text-align: center; }
.about .avatar {
  width: 120px; height: 120px; border-radius: 50%;
  object-fit: cover; margin: 10px auto 18px;
  border: 2px solid var(--border); box-shadow: var(--shadow);
}
.about h1 { font-family: var(--serif); color: var(--text); font-size: 1.8rem; margin: 0 0 6px; }
.about .role { color: var(--text-dim); letter-spacing: .1em; margin-bottom: 22px; }
.about p { color: #cdd9ea; text-align: left; line-height: 1.95; }
[data-theme="light"] .about p { color: var(--text); }
.about-stats { display: flex; justify-content: center; gap: 30px; margin: 26px 0 8px; }
.about-stats .num { font-family: var(--serif); font-size: 1.7rem; color: var(--accent); }
.about-stats .lbl { color: var(--text-dim); font-size: .82rem; }

/* ---------- 阅读进度条 ---------- */
.progress {
  position: fixed; top: 0; left: 0; right: 0; height: 3px;
  z-index: 70; background: transparent;
}
.progress-bar {
  height: 100%; width: 0;
  background: linear-gradient(90deg, #acd4ff, #e8f4ff);
  transition: width .1s linear;
}
[data-theme="light"] .progress-bar { background: linear-gradient(90deg, #2f6fd0, #184d96); }

/* ---------- 响应式 ---------- */
@media (max-width: 760px) {
  .footer-widgets { grid-template-columns: 1fr; gap: 30px; }
  .banner { background-attachment: scroll; min-height: 54vh; }
  .post-feature { height: 200px; }
  .navbar-inner { flex-wrap: wrap; }
  .menu { order: 3; flex-basis: 100%; justify-content: center; }
  .theme-toggle { margin-left: auto; }
}