/* ==========================================================================
   奶油小星球 · 博客首页样式表
   --------------------------------------------------------------------------
   目录
   01. 设计令牌（颜色 / 圆角 / 阴影 / 深色模式）
   02. 基础重置与全局排版
   03. 通用组件（按钮 / 标签 / 卡片 / 输入框 / 头像）
   04. 顶部导航、搜索与移动端抽屉
   05. 精选文章轮播
   06. 标签云
   07. 文章列表
   08. 侧边栏
   09. 页脚与浮动按钮
   10. 动画与滚动出现
   11. 雨幕背景（CSS 雨丝纹理 + JS 雨滴）
   12. 响应式与无障碍降级
   ========================================================================== */

/* ==========================================================================
   01. 设计令牌
   ========================================================================== */
:root {
  /* —— 表面与文字 —— */
  --bg: #f5f9ff;
  --bg-soft: #eef5ff;
  --surface: #ffffff;
  --surface-2: #eef4fd;
  --ink: #1f2b3d;
  --ink-soft: #53627a;
  --ink-mute: #8b98ac;
  --line: #e2eaf5;

  /* —— 主题色（奶油系）—— */
  --blue: #3b82f6;
  --blue-soft: #dbeafe;
  --indigo: #6366f1;
  --indigo-soft: #e0e7ff;
  --cyan: #06b6d4;
  --cyan-soft: #cffafe;
  --sky: #38bdf8;
  --sky-soft: #e0f2fe;
  --yellow: #60a5fa;

  /* —— 圆角 —— */
  --r-sm: 14px;
  --r-md: 20px;
  --r-lg: 26px;
  --r-xl: 34px;

  /* —— 阴影 —— */
  --shadow-sm: 0 2px 10px rgba(59, 130, 246, 0.08);
  --shadow: 0 12px 30px -12px rgba(59, 130, 246, 0.38);
  --shadow-lg: 0 28px 60px -24px rgba(37, 99, 235, 0.45);

  /* —— 动效节奏 —— */
  --ease-pop: cubic-bezier(0.34, 1.28, 0.64, 1); /* 轻微回弹，克制不浮夸 */
  --ease-smooth: cubic-bezier(0.22, 0.61, 0.36, 1);
}

/* 深色模式：仅替换令牌，组件自动跟随 */
html.dark {
  --bg: #0b1220;
  --bg-soft: #0e1729;
  --surface: #131c2e;
  --surface-2: #1a253a;
  --ink: #e8f0fb;
  --ink-soft: #b6c4d8;
  --ink-mute: #7d8da3;
  --line: #26344c;
  --blue-soft: #1c3450;
  --indigo-soft: #26305c;
  --cyan-soft: #0e3a44;
  --sky-soft: #0e2f45;
  --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.4);
  --shadow: 0 12px 30px -12px rgba(0, 0, 0, 0.6);
  --shadow-lg: 0 28px 60px -24px rgba(0, 0, 0, 0.7);
}

/* ==========================================================================
   02. 基础重置与全局排版
   ========================================================================== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  scroll-padding-top: 6rem; /* 锚点跳转时避开吸顶导航 */
}

body {
  margin: 0;
  min-height: 100vh;
  /* 背景：冷色调云层渐变（雨丝与雨滴由 .rain 层负责，见第 11 节） */
  background-color: var(--bg);
  background-image:
    radial-gradient(ellipse 70% 45% at 15% -5%, rgba(59, 130, 246, 0.15), transparent 60%),
    radial-gradient(ellipse 60% 40% at 92% 2%, rgba(99, 102, 241, 0.12), transparent 58%),
    radial-gradient(ellipse 80% 50% at 60% 100%, rgba(6, 182, 212, 0.1), transparent 62%);
  background-attachment: fixed;
  line-height: 1.7;
  transition: background-color 0.4s var(--ease-smooth), color 0.4s var(--ease-smooth);
}

html.dark body {
  background-image:
    radial-gradient(ellipse 70% 45% at 15% -5%, rgba(59, 130, 246, 0.24), transparent 60%),
    radial-gradient(ellipse 60% 40% at 92% 2%, rgba(99, 102, 241, 0.2), transparent 58%),
    radial-gradient(ellipse 80% 50% at 60% 100%, rgba(6, 182, 212, 0.14), transparent 62%);
}

/* 自定义滚动条 */
::-webkit-scrollbar {
  width: 12px;
  height: 12px;
}

::-webkit-scrollbar-track {
  background: var(--surface-2);
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(var(--blue), var(--indigo));
  border: 3px solid var(--surface-2);
  border-radius: 99px;
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(var(--indigo), var(--blue));
}

::selection {
  background: var(--blue-soft);
  color: var(--ink);
}

/* 统一的键盘焦点样式（无障碍） */
:focus-visible {
  outline: 3px solid var(--indigo);
  outline-offset: 3px;
  border-radius: 6px;
}

/* hidden 属性优先于组件自身的 display（保证 JS 显隐切换可靠） */
[hidden] {
  display: none !important;
}

/* 屏幕阅读器专用文本 */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* 跳到主要内容 */
.skip-link {
  position: fixed;
  top: -100px;
  left: 50%;
  z-index: 100;
  transform: translateX(-50%);
  padding: 0.7rem 1.4rem;
  background: var(--blue);
  color: #fff;
  font-weight: 700;
  border-radius: 0 0 var(--r-md) var(--r-md);
  transition: top 0.25s var(--ease-pop);
}

.skip-link:focus {
  top: 0;
}

/* 区块标题：统一黑体，仅靠字重与字距区分层级 */
.section-title {
  font-size: clamp(1.3rem, 1rem + 1vw, 1.6rem);
  font-weight: 700;
  line-height: 1.35;
  display: inline-block;
  position: relative;
  letter-spacing: -0.01em;
}

/* 标题下的细渐变短线（替代原先的波点装饰） */
.section-title::after {
  content: '';
  display: block;
  width: 46px;
  height: 3px;
  margin-top: 9px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--blue), var(--indigo));
}

.section-sub {
  margin-top: 0.35rem;
  font-size: 0.85rem;
  color: var(--ink-mute);
}

/* ==========================================================================
   03. 通用组件
   ========================================================================== */

/* —— 按钮：主按钮 —— */
.btn-cute {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.72rem 1.5rem;
  border: none;
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 700;
  color: #fff;
  cursor: pointer;
  text-decoration: none;
  position: relative;
  overflow: hidden;
  background-image: linear-gradient(135deg, var(--blue), #60a5fa 45%, var(--indigo));
  background-size: 160% 160%;
  box-shadow: 0 10px 22px -10px rgba(59, 130, 246, 0.85), inset 0 -2px 0 rgba(0, 0, 0, 0.08);
  transition: transform 0.28s var(--ease-pop), box-shadow 0.28s var(--ease-smooth),
    background-position 0.5s var(--ease-smooth);
}

/* 按钮上的光泽扫过效果 */
.btn-cute::after {
  content: '';
  position: absolute;
  inset: 0 auto 0 -60%;
  width: 45%;
  background: linear-gradient(100deg, transparent, rgba(255, 255, 255, 0.55), transparent);
  transform: skewX(-18deg);
  transition: left 0.6s var(--ease-smooth);
}

.btn-cute:hover {
  transform: translateY(-3px) scale(1.03);
  background-position: 100% 50%;
  box-shadow: 0 16px 28px -12px rgba(59, 130, 246, 0.95);
}

.btn-cute:hover::after {
  left: 130%;
}

.btn-cute:active {
  transform: translateY(0) scale(0.96);
}

/* —— 按钮：次级 —— */
.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.72rem 1.4rem;
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  text-decoration: none;
  background: var(--surface);
  border: 2px dashed var(--blue-soft);
  transition: transform 0.28s var(--ease-pop), border-color 0.28s, background 0.28s;
}

.btn-ghost:hover {
  transform: translateY(-2px);
  border-color: var(--blue);
  background: var(--surface-2);
}

.btn-ghost:active {
  transform: scale(0.96);
}

/* —— 圆形图标按钮（主题切换 / 关闭等）—— */
.icon-btn {
  display: inline-grid;
  place-items: center;
  width: 42px;
  height: 42px;
  padding: 0;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  color: var(--ink);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s var(--ease-pop), background 0.3s, box-shadow 0.3s;
}

.icon-btn svg {
  width: 20px;
  height: 20px;
}

.icon-btn:hover {
  transform: translateY(-2px);
  background: var(--blue-soft);
  box-shadow: var(--shadow);
}

.icon-btn:active {
  transform: scale(0.9);
}

.theme-icon {
  font-size: 1.05rem;
  line-height: 1;
  display: block;
}

/* —— 用户入口按钮 —— */
.btn-user {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.38rem 0.95rem 0.38rem 0.4rem;
  border-radius: 999px;
  text-decoration: none;
  color: var(--ink);
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s var(--ease-pop), box-shadow 0.3s;
}

.btn-user:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

/* —— 头像（姓名首字母，零图片请求）—— */
.avatar {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  flex: none;
  border-radius: 50%;
  font-family: 'Baloo 2', 'Noto Sans SC', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
  background: linear-gradient(135deg, var(--blue-soft), var(--indigo-soft));
  box-shadow: inset 0 0 0 2px var(--surface);
}

.avatar-sm {
  width: 30px;
  height: 30px;
  font-size: 0.78rem;
}

/* —— 分类徽章 —— */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.24rem 0.7rem;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 700;
  white-space: nowrap;
  background: var(--surface-2);
  color: var(--ink-soft);
}

.chip--blue { background: var(--blue-soft); color: #1d4ed8; }
.chip--indigo { background: var(--indigo-soft); color: #4338ca; }
.chip--cyan { background: var(--cyan-soft); color: #0e7490; }
.chip--sky { background: var(--sky-soft); color: #0369a1; }

html.dark .chip--blue { color: #93c5fd; }
html.dark .chip--indigo { color: #a5b4fc; }
html.dark .chip--cyan { color: #67e8f9; }
html.dark .chip--sky { color: #7dd3fc; }

/* —— 输入框 —— */
.input-cute {
  width: 100%;
  padding: 0.8rem 1rem;
  font: inherit;
  font-size: 0.9rem;
  color: var(--ink);
  background: var(--surface-2);
  border: 2px solid transparent;
  border-radius: var(--r-md);
  transition: border-color 0.25s, background 0.25s, box-shadow 0.25s;
}

.input-cute::placeholder {
  color: var(--ink-mute);
}

.input-cute:focus {
  outline: none;
  background: var(--surface);
  border-color: var(--blue);
  box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.18);
}

/* —— 卡片基类 —— */
.side-card {
  padding: 1.4rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow);
}

.side-card__title {
  font-size: 1.02rem;
  font-weight: 700; /* 抵消 Tailwind preflight 对标题字重的重置 */
  letter-spacing: -0.01em;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

/* —— 轻提示 Toast —— */
.toast {
  position: fixed;
  left: 50%;
  bottom: 2rem;
  z-index: 200;
  pointer-events: none; /* 纯提示，不拦截点击 */
  transform: translate(-50%, 130%);
  padding: 0.85rem 1.5rem;
  max-width: min(90vw, 420px);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--ink);
  text-align: center;
  background: var(--surface);
  border: 2px solid var(--blue-soft);
  border-radius: 999px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  transition: transform 0.45s var(--ease-pop), opacity 0.35s;
}

.toast.is-visible {
  transform: translate(-50%, 0);
  opacity: 1;
}

/* ==========================================================================
   04. 顶部导航、搜索与移动端抽屉
   ========================================================================== */
.nav-bar {
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}

/* 兼容不支持 color-mix 的旧浏览器 */
@supports not (background: color-mix(in srgb, red 50%, blue)) {
  .nav-bar {
    background: rgba(245, 249, 255, 0.88);
  }
  html.dark .nav-bar {
    background: rgba(11, 18, 32, 0.88);
  }
}

/* —— 站点名称：仅四个字母，作为主标识 —— */
.site-name {
  font-size: 1.4rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.03em;
  color: var(--ink);
  transition: color 0.25s;
}

a:hover > .site-name {
  color: var(--blue);
}

/* —— 抽屉标题 —— */
.drawer-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--ink);
}

/* —— 分类导航项 —— */
.nav-link {
  padding: 0.5rem 0.9rem;
  border: none;
  border-radius: 999px;
  font: inherit;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--ink-soft);
  background: transparent;
  cursor: pointer;
  transition: color 0.25s, background 0.3s var(--ease-smooth), transform 0.3s var(--ease-pop);
}

.nav-link:hover {
  color: var(--ink);
  background: var(--surface-2);
  transform: translateY(-2px);
}

.nav-link.is-active {
  color: #fff;
  background: linear-gradient(135deg, var(--blue), var(--indigo));
  box-shadow: 0 8px 18px -10px rgba(59, 130, 246, 0.9);
}

/* —— 搜索 —— */
.search-form {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  height: 42px;
  padding: 0 0.5rem 0 0.8rem;
  background: var(--surface);
  border: 2px solid var(--line);
  border-radius: 999px;
  box-shadow: var(--shadow-sm);
  transition: width 0.4s var(--ease-smooth), border-color 0.3s, box-shadow 0.3s;
  width: clamp(120px, 26vw, 190px);
}

.search-form:focus-within {
  border-color: var(--blue);
  box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.16);
  width: clamp(180px, 42vw, 280px);
}

.search-icon-btn {
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  flex: none;
  padding: 0;
  border: none;
  border-radius: 50%;
  color: var(--ink-mute);
  background: transparent;
  cursor: pointer;
  transition: color 0.25s, transform 0.3s var(--ease-pop);
}

.search-icon-btn svg {
  width: 17px;
  height: 17px;
}

.search-icon-btn:hover {
  color: var(--blue);
  transform: scale(1.08);
}

.search-input {
  width: 100%;
  min-width: 0;
  border: none;
  outline: none;
  font: inherit;
  font-size: 0.87rem;
  color: var(--ink);
  background: transparent;
}

/* 隐藏原生 search 清除按钮，使用自定义按钮 */
.search-input::-webkit-search-cancel-button {
  display: none;
}

.search-clear {
  display: grid;
  place-items: center;
  width: 24px;
  height: 24px;
  flex: none;
  padding: 0;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  color: var(--ink-mute);
  background: var(--surface-2);
  transition: transform 0.25s var(--ease-pop), color 0.25s;
}

.search-clear svg {
  width: 13px;
  height: 13px;
}

.search-clear:hover {
  transform: rotate(90deg) scale(1.1);
  color: var(--blue);
}

/* 搜索结果面板 */
.search-panel {
  position: absolute;
  top: calc(100% + 12px);
  right: 0;
  width: min(92vw, 380px);
  max-height: 420px;
  overflow-y: auto;
  padding: 0.6rem;
  background: var(--surface);
  border: 2px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-lg);
  animation: pop-in 0.28s var(--ease-pop) both;
}

.search-group-title {
  padding: 0.5rem 0.75rem 0.3rem;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--ink-mute);
}

.search-item {
  display: flex;
  gap: 0.7rem;
  align-items: center;
  padding: 0.6rem 0.75rem;
  border-radius: var(--r-md);
  text-decoration: none;
  color: var(--ink);
  transition: background 0.2s, transform 0.2s var(--ease-pop);
}

.search-item:hover,
.search-item.is-highlight {
  background: var(--surface-2);
  transform: translateX(3px);
}

/* 搜索结果左侧：分类首字标记 */
.search-item__emoji {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: none;
  font-size: 0.82rem;
  font-weight: 700;
  color: var(--ink);
  border-radius: 12px;
  background: linear-gradient(135deg, var(--blue-soft), var(--indigo-soft));
}

.search-item__text {
  min-width: 0;
}

.search-item__title {
  font-size: 0.86rem;
  font-weight: 600;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 1;
  -webkit-box-orient: vertical;
}

.search-item__meta {
  font-size: 0.72rem;
  color: var(--ink-mute);
}

.search-empty {
  padding: 1.5rem 1rem;
  text-align: center;
  font-size: 0.85rem;
  color: var(--ink-mute);
}

/* —— 移动端抽屉 —— */
.drawer {
  position: fixed;
  inset: 0;
  z-index: 90;
  pointer-events: none;
}

.drawer-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(15, 23, 42, 0.45);
  backdrop-filter: blur(2px);
  opacity: 0;
  transition: opacity 0.35s var(--ease-smooth);
}

.drawer-panel {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: min(84vw, 340px);
  padding: 1.5rem;
  background: var(--surface);
  border-left: 2px solid var(--line);
  border-radius: var(--r-xl) 0 0 var(--r-xl);
  box-shadow: var(--shadow-lg);
  transform: translateX(100%);
  transition: transform 0.42s var(--ease-pop);
  overflow-y: auto;
}

.drawer.is-open {
  pointer-events: auto;
}

.drawer.is-open .drawer-backdrop {
  opacity: 1;
}

.drawer.is-open .drawer-panel {
  transform: translateX(0);
}

.drawer-link {
  display: block;
  width: 100%;
  padding: 0.85rem 1rem;
  text-align: left;
  font: inherit;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--ink);
  background: var(--surface-2);
  border: none;
  border-radius: var(--r-md);
  cursor: pointer;
  transition: transform 0.28s var(--ease-pop), background 0.25s;
}

.drawer-link:hover,
.drawer-link.is-active {
  transform: translateX(5px);
  background: var(--blue-soft);
}

/* ==========================================================================
   05. 精选文章轮播
   ========================================================================== */
.carousel {
  position: relative;
}

/* 背景光斑（装饰） */
.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(70px);
  opacity: 0.32;
  pointer-events: none;
  z-index: 0;
}

.blob--blue {
  width: 260px;
  height: 260px;
  top: -60px;
  left: -40px;
  background: var(--blue);
  animation: float-slow 14s ease-in-out infinite;
}

.blob--indigo {
  width: 300px;
  height: 300px;
  right: -60px;
  bottom: -80px;
  background: var(--indigo);
  animation: float-slow 18s ease-in-out infinite reverse;
}

.carousel-viewport {
  position: relative;
  z-index: 1;
  min-height: 540px;
  border-radius: var(--r-xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  isolation: isolate;
}

.carousel-viewport:focus-visible {
  outline-offset: 6px;
}

.carousel-track {
  position: relative;
  min-height: inherit;
}

.carousel-slide {
  position: relative;
}

/* 有 JS 时，才启用「同一网格单元叠放 + 淡入淡出」：
   用 grid 叠放可自动取最高一张幻灯片的高度，视觉更稳定；无 JS 时则顺序排列。 */
.js .carousel-track {
  display: grid;
}

.js .carousel-slide {
  grid-area: 1 / 1;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.65s var(--ease-smooth), visibility 0.65s;
}

.js .carousel-slide.is-active {
  opacity: 1;
  visibility: visible;
}

.slide-inner {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1.5rem;
  height: 100%;
  padding: 2.25rem 1.6rem;
  background: linear-gradient(135deg, var(--slide-a), var(--slide-b));
  position: relative;
  overflow: hidden;
}

/* 幻灯片配色主题 */
.slide-theme--blue { --slide-a: #dbeafe; --slide-b: #e0e7ff; }
.slide-theme--indigo { --slide-a: #e0e7ff; --slide-b: #cffafe; }
.slide-theme--cyan { --slide-a: #cffafe; --slide-b: #dbeafe; }

html.dark .slide-theme--blue { --slide-a: #14243d; --slide-b: #1b2450; }
html.dark .slide-theme--indigo { --slide-a: #1b2450; --slide-b: #0d3440; }
html.dark .slide-theme--cyan { --slide-a: #0d3440; --slide-b: #14243d; }

/* 幻灯片内的柔光装饰 */
.slide-inner::before {
  content: '';
  position: absolute;
  width: 320px;
  height: 320px;
  right: -80px;
  top: -110px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.45);
  filter: blur(10px);
  pointer-events: none;
}

html.dark .slide-inner::before {
  background: rgba(255, 255, 255, 0.06);
}

.slide-copy {
  position: relative;
  z-index: 2;
  max-width: 34rem;
}

.slide-title {
  margin: 0.85rem 0 0;
  font-size: clamp(1.45rem, 1.1rem + 1.9vw, 2.1rem);
  font-weight: 700; /* Tailwind preflight 会把标题字重重置为 inherit，这里显式声明 */
  line-height: 1.32;
  letter-spacing: -0.01em;
}

.slide-desc {
  margin-top: 0.8rem;
  max-width: 30rem;
  font-size: 0.94rem;
  color: var(--ink-soft);
}

.slide-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  margin-top: 1.1rem;
  font-size: 0.8rem;
  color: var(--ink-soft);
}

/* 幻灯片插画区：抽象几何装饰（不使用 emoji） */
.slide-art {
  position: absolute;
  right: 6%;
  top: 50%;
  transform: translateY(-50%);
  display: grid;
  place-items: center;
  width: 210px;
  height: 210px;
  z-index: 1;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.45);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.7);
}

html.dark .slide-art {
  background: rgba(255, 255, 255, 0.07);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.1);
}

/* 内部缓慢旋转的虚线圆环 */
.art-ring {
  width: 58%;
  height: 58%;
  border-radius: 50%;
  border: 2px dashed rgba(255, 255, 255, 0.95);
  animation: spin 28s linear infinite;
}

html.dark .art-ring {
  border-color: rgba(255, 255, 255, 0.2);
}

/* 三个渐变小圆点（呼应主题色） */
.art-dot {
  position: absolute;
  border-radius: 50%;
}

.art-dot--1 {
  width: 46px;
  height: 46px;
  top: 10%;
  left: 8%;
  background: linear-gradient(135deg, var(--blue), #93c5fd);
  animation: bob 7s ease-in-out infinite;
}

.art-dot--2 {
  width: 32px;
  height: 32px;
  right: 10%;
  bottom: 18%;
  background: linear-gradient(135deg, var(--indigo), #a5b4fc);
  animation: bob 8s ease-in-out infinite reverse;
}

.art-dot--3 {
  width: 20px;
  height: 20px;
  left: 24%;
  bottom: 8%;
  background: linear-gradient(135deg, var(--cyan), #67e8f9);
  animation: bob 9s ease-in-out infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* 切换箭头 */
.carousel-arrow {
  position: absolute;
  /* 视口下方还有指示点区域，向上偏移以保持视觉居中 */
  top: calc(50% - 16px);
  z-index: 3;
  display: grid;
  place-items: center;
  width: 46px;
  height: 46px;
  padding: 0;
  margin-top: -23px;
  border: 2px solid var(--line);
  border-radius: 50%;
  color: var(--ink);
  background: var(--surface);
  box-shadow: var(--shadow);
  cursor: pointer;
  transition: transform 0.3s var(--ease-pop), background 0.3s, color 0.3s;
}

.carousel-arrow svg {
  width: 20px;
  height: 20px;
}

.carousel-arrow--prev { left: 0.9rem; }
.carousel-arrow--next { right: 0.9rem; }

.carousel-arrow:hover {
  background: var(--blue);
  color: #fff;
  border-color: var(--blue);
}

.carousel-arrow--prev:hover { transform: translateX(-4px) scale(1.08); }
.carousel-arrow--next:hover { transform: translateX(4px) scale(1.08); }

.carousel-arrow:active {
  transform: scale(0.92);
}

/* 底部：指示点 + 播放进度 */
.carousel-footer {
  position: relative;
  z-index: 3;
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: 1.1rem;
  padding: 0 0.4rem;
}

.carousel-dots {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.carousel-dot {
  width: 10px;
  height: 10px;
  padding: 0;
  border: none;
  border-radius: 999px;
  background: var(--blue-soft);
  cursor: pointer;
  transition: width 0.4s var(--ease-pop), background 0.3s;
}

.carousel-dot:hover {
  background: var(--blue);
}

.carousel-dot.is-active {
  width: 30px;
  background: linear-gradient(90deg, var(--blue), var(--indigo));
}

.carousel-progress {
  flex: 1;
  height: 6px;
  border-radius: 999px;
  background: var(--surface-2);
  overflow: hidden;
}

.carousel-progress > span {
  display: block;
  height: 100%;
  width: 0;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--blue), var(--indigo));
}

.carousel-progress > span.is-running {
  animation: grow 5.5s linear forwards;
}

@keyframes grow {
  from { width: 0; }
  to { width: 100%; }
}

/* ==========================================================================
   06. 标签云
   ========================================================================== */
.cloud-card {
  padding: 1.6rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow);
  background-image: radial-gradient(circle at 96% 10%, var(--indigo-soft), transparent 45%);
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.tag {
  padding: 0.45rem 1rem;
  border: 2px solid transparent;
  border-radius: 999px;
  font: inherit;
  font-weight: 700;
  color: var(--ink-soft);
  background: var(--surface-2);
  cursor: pointer;
  transition: transform 0.32s var(--ease-pop), color 0.25s, background 0.3s, border-color 0.3s;
}

.tag--sm { font-size: 0.8rem; }
.tag--md { font-size: 0.88rem; }
.tag--lg { font-size: 0.98rem; padding: 0.5rem 1.15rem; }
.tag--xl { font-size: 1.08rem; padding: 0.55rem 1.3rem; }

.tag:hover {
  transform: translateY(-2px);
  color: #fff;
  background: linear-gradient(135deg, var(--indigo), var(--blue));
}

.tag.is-active {
  color: #fff;
  background: linear-gradient(135deg, var(--blue), var(--indigo));
  border-color: var(--surface);
  box-shadow: 0 10px 20px -10px rgba(59, 130, 246, 0.9);
  transform: translateY(-2px);
}

/* ==========================================================================
   07. 文章列表
   ========================================================================== */
.post-card {
  display: flex;
  gap: 1.1rem;
  padding: 1.1rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-xl);
  box-shadow: var(--shadow-sm);
  transition: transform 0.4s var(--ease-pop), box-shadow 0.4s var(--ease-smooth), border-color 0.3s;
  will-change: transform;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--blue-soft);
}

/* 文章封面：纯 CSS 渐变色块 + 抽象装饰（零图片请求） */
.post-cover {
  display: block;
  width: 118px;
  flex: none;
  position: relative;
  overflow: hidden;
  border-radius: var(--r-lg);
  text-decoration: none;
  transition: transform 0.45s var(--ease-pop);
}

.post-card:hover .post-cover {
  transform: scale(1.03);
}

/* 封面内的柔光圆 */
.post-cover::before {
  content: '';
  position: absolute;
  width: 92px;
  height: 92px;
  right: -28px;
  bottom: -32px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.5);
}

/* 封面内的细点纹理 */
.post-cover::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(255, 255, 255, 0.6) 1.4px, transparent 1.5px);
  background-size: 14px 14px;
  opacity: 0.55;
}

.cover--blue { background: linear-gradient(150deg, #dbeafe, #bfdbfe); }
.cover--indigo { background: linear-gradient(150deg, #e0e7ff, #a5b4fc); }
.cover--cyan { background: linear-gradient(150deg, #cffafe, #a5f3fc); }
.cover--sky { background: linear-gradient(150deg, #e0f2fe, #bae6fd); }

html.dark .cover--blue { background: linear-gradient(150deg, #1c3450, #25456b); }
html.dark .cover--indigo { background: linear-gradient(150deg, #26305c, #33407a); }
html.dark .cover--cyan { background: linear-gradient(150deg, #0e3a44, #155560); }
html.dark .cover--sky { background: linear-gradient(150deg, #0e2f45, #154060); }

.post-body {
  min-width: 0;
  flex: 1;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.74rem;
  color: var(--ink-mute);
}

.post-title {
  margin: 0.5rem 0 0;
  font-size: 1.06rem;
  line-height: 1.5;
  font-weight: 700;
}

.post-title a {
  color: var(--ink);
  text-decoration: none;
  background-image: linear-gradient(var(--blue), var(--blue));
  background-repeat: no-repeat;
  background-size: 0 3px;
  background-position: 0 100%;
  transition: background-size 0.4s var(--ease-smooth), color 0.25s;
}

.post-title a:hover {
  color: var(--blue);
  background-size: 100% 3px;
}

.post-excerpt {
  margin: 0.5rem 0 0;
  font-size: 0.87rem;
  color: var(--ink-soft);
}

.post-foot {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem;
  margin-top: 0.85rem;
  padding-top: 0.75rem;
  border-top: 1px dashed var(--line);
  font-size: 0.78rem;
  color: var(--ink-mute);
}

.author {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-weight: 600;
  color: var(--ink-soft);
}

.post-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--indigo);
  font-weight: 600;
}

/* 空状态 */
.empty-state {
  padding: 3rem 1rem;
  text-align: center;
  background: var(--surface);
  border: 2px dashed var(--blue-soft);
  border-radius: var(--r-xl);
}

.empty-title {
  font-size: 1.02rem;
  font-weight: 700;
}

/* ==========================================================================
   08. 侧边栏
   ========================================================================== */
.about-avatar {
  display: grid;
  place-items: center;
  width: 68px;
  height: 68px;
  font-family: 'Baloo 2', 'Noto Sans SC', sans-serif;
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--ink);
  border-radius: 24px;
  background: linear-gradient(135deg, var(--blue-soft), var(--indigo-soft) 65%, var(--cyan-soft));
  box-shadow: var(--shadow), inset 0 -3px 0 rgba(255, 255, 255, 0.6);
}

/* 作者名与身份 */
.about-name {
  margin-top: 0.85rem;
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.about-role {
  margin-top: 0.15rem;
  font-size: 0.75rem;
  color: var(--ink-mute);
}

.stat {
  padding: 0.6rem 0.2rem;
  border-radius: var(--r-sm);
  background: var(--surface-2);
}

.stat-label {
  font-size: 0.68rem;
  color: var(--ink-mute);
}

.stat-value {
  margin: 0;
  font-family: 'Baloo 2', cursive;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--blue);
}

.hot-list {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: hot;
}

.hot-list li {
  display: flex;
  align-items: flex-start;
  gap: 0.7rem;
  padding: 0.6rem 0;
  border-bottom: 1px dashed var(--line);
}

.hot-list li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.hot-rank {
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  flex: none;
  font-family: 'Baloo 2', cursive;
  font-size: 0.8rem;
  font-weight: 800;
  color: var(--ink-soft);
  background: var(--surface-2);
  border-radius: 10px;
}

.hot-rank--1 { color: #fff; background: linear-gradient(135deg, #3b82f6, #93c5fd); }
.hot-rank--2 { color: #fff; background: linear-gradient(135deg, #6366f1, #a5b4fc); }
.hot-rank--3 { color: #fff; background: linear-gradient(135deg, #06b6d4, #67e8f9); }

.hot-link {
  display: block;
  min-width: 0;
  text-decoration: none;
  transition: transform 0.3s var(--ease-pop);
}

.hot-link:hover {
  transform: translateX(4px);
}

.hot-name {
  display: block;
  font-size: 0.87rem;
  font-weight: 600;
  color: var(--ink);
  line-height: 1.5;
}

.hot-link:hover .hot-name {
  color: var(--blue);
}

.hot-meta {
  display: block;
  font-size: 0.72rem;
  color: var(--ink-mute);
}

/* 订阅卡片 */
.subscribe-card {
  background-image: linear-gradient(160deg, var(--blue-soft), var(--surface) 55%);
  border: 2px dashed var(--blue-soft);
}

html.dark .subscribe-card {
  background-image: linear-gradient(160deg, var(--blue-soft), var(--surface) 55%);
}

/* ==========================================================================
   09. 页脚与浮动按钮
   ========================================================================== */
.footer {
  background: var(--bg-soft);
  border-top: 1px solid var(--line);
}

.footer-title {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 0.9rem;
}

.footer-list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  font-size: 0.86rem;
}

.footer-list a {
  color: var(--ink-soft);
  text-decoration: none;
  transition: color 0.25s, transform 0.3s var(--ease-pop);
  display: inline-block;
}

.footer-list a:hover {
  color: var(--blue);
  transform: translateX(4px);
}

.footer-contact {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--ink-soft);
  text-decoration: none;
}

.footer-contact:hover {
  color: var(--blue);
}

/* 社交媒体：文字胶囊（替代图标，更简洁） */
.social-btn {
  display: inline-flex;
  align-items: center;
  padding: 0.45rem 0.95rem;
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--ink-soft);
  border-radius: 999px;
  text-decoration: none;
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  transition: transform 0.3s var(--ease-pop), box-shadow 0.3s, background 0.3s, color 0.3s;
}

.social-btn:hover {
  transform: translateY(-3px);
  color: var(--ink);
  background: var(--blue-soft);
  box-shadow: var(--shadow);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.6rem;
  margin-top: 2.5rem;
  padding-top: 1.4rem;
  border-top: 1px dashed var(--line);
  font-size: 0.8rem;
  color: var(--ink-mute);
}

.footer-bottom a {
  color: inherit;
  text-decoration: none;
}

.footer-bottom a:hover {
  color: var(--blue);
}

/* 回到顶部 */
.back-to-top {
  position: fixed;
  right: 1.2rem;
  bottom: 1.6rem;
  z-index: 80;
  display: grid;
  place-items: center;
  width: 50px;
  height: 50px;
  padding: 0;
  border: 2px solid var(--line);
  border-radius: 50%;
  color: #fff;
  cursor: pointer;
  background: linear-gradient(135deg, var(--blue), var(--indigo));
  box-shadow: var(--shadow-lg);
  opacity: 0;
  pointer-events: none; /* 隐藏时不拦截点击 */
  transform: translateY(20px) scale(0.8);
  transition: opacity 0.35s, transform 0.45s var(--ease-pop), filter 0.3s;
}

.back-to-top svg {
  width: 22px;
  height: 22px;
}

.back-to-top.is-visible {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0) scale(1);
}

.back-to-top:hover {
  filter: brightness(1.08);
  transform: translateY(-4px) scale(1.06);
}

.back-to-top:active {
  transform: scale(0.92);
}

/* ==========================================================================
   10. 动画与滚动出现
   ========================================================================== */
@keyframes bob {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-12px) rotate(3deg); }
}

@keyframes float-slow {
  0%, 100% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(24px, -18px) scale(1.08); }
}

@keyframes pop-in {
  from { opacity: 0; transform: translateY(-10px) scale(0.96); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

/* 滚动出现：仅在有 JS 时生效，避免内容被永久隐藏 */
.js .reveal {
  opacity: 0;
  transform: translateY(26px);
  transition: opacity 0.7s var(--ease-smooth), transform 0.7s var(--ease-pop);
  transition-delay: var(--reveal-delay, 0ms);
}

.js .reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* 幻灯片激活时，内容轻微上浮 */
.js .carousel-slide.is-active .slide-copy > * {
  animation: slide-up 0.7s var(--ease-pop) both;
}

.js .carousel-slide.is-active .slide-copy > *:nth-child(2) { animation-delay: 0.08s; }
.js .carousel-slide.is-active .slide-copy > *:nth-child(3) { animation-delay: 0.16s; }
.js .carousel-slide.is-active .slide-copy > *:nth-child(4) { animation-delay: 0.24s; }
.js .carousel-slide.is-active .slide-copy > *:nth-child(5) { animation-delay: 0.32s; }

@keyframes slide-up {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: none; }
}

/* ==========================================================================
   11. 雨幕背景
   --------------------------------------------------------------------------
   分两层叠加：
   · .rain::before / ::after：纯 CSS 的斜向雨丝纹理 + 顶部云层光晕，体现整体氛围
   · .rain-drop：由 JS 依屏幕尺寸动态生成，每条随机位置 / 速度 / 透明度 / 长短
   z-index: -1 让它位于「内容之下、页面背景之上」，且 pointer-events 关闭，不影响任何点击。
   ========================================================================== */
.rain {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

/* 斜向雨丝纹理，缓慢向下滚动形成雨幕 */
.rain::before {
  content: '';
  position: absolute;
  inset: -30% -20%;
  background-image: repeating-linear-gradient(104deg,
      rgba(147, 197, 253, 0.3) 0 1px,
      transparent 1px 10px);
  animation: rain-drift 1.6s linear infinite;
}

/* 顶部云层光晕 + 自上而下的冷色渐变 */
.rain::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(ellipse 85% 42% at 50% -6%, rgba(96, 165, 250, 0.26), transparent 68%),
    linear-gradient(180deg, rgba(59, 130, 246, 0.08), transparent 42%);
}

@keyframes rain-drift {
  from { transform: translate3d(0, -12%, 0); }
  to { transform: translate3d(-4%, 12%, 0); }
}

/* 单条雨滴：所有参数通过内联 CSS 变量注入 */
.rain-drop {
  position: absolute;
  top: -12%;
  left: var(--left, 50%);
  width: 1px;
  height: var(--h, 70px);
  opacity: var(--op, 0.5);
  border-radius: 999px;
  background-image: linear-gradient(180deg, transparent, rgba(96, 165, 250, 0.85));
  animation: rain-fall var(--dur, 0.9s) linear infinite;
  animation-delay: var(--delay, 0s);
}

/* 每秒 0.6~1.3 屏的下落速度 + 轻微斜切，模拟被风吹斜的雨 */
@keyframes rain-fall {
  from { transform: translate3d(0, 0, 0) rotate(12deg); }
  to { transform: translate3d(-16vw, 120vh, 0) rotate(12deg); }
}

/* 深色模式：雨线提亮，避免在深底上糊成一团 */
html.dark .rain::before {
  background-image: repeating-linear-gradient(104deg,
      rgba(147, 197, 253, 0.22) 0 1px,
      transparent 1px 10px);
}

html.dark .rain-drop {
  background-image: linear-gradient(180deg, transparent, rgba(191, 219, 254, 0.8));
}

/* ==========================================================================
   12. 响应式与无障碍降级
   ========================================================================== */

/* 平板及以上：轮播改为左右布局 */
@media (min-width: 768px) {
  .slide-inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    padding: 2.5rem 3.5rem;
  }

  .slide-art {
    position: relative;
    right: auto;
    top: auto;
    transform: none;
    width: 230px;
    height: 230px;
    flex: none;
  }

  .carousel-viewport {
    min-height: 400px;
  }

  .carousel-arrow--prev { left: 1.4rem; }
  .carousel-arrow--next { right: 1.4rem; }
}

@media (min-width: 1024px) {
  .carousel-viewport {
    min-height: 380px;
  }
}

/* 小屏：插画缩小并淡化为背景装饰，避免遮挡文字 */
@media (max-width: 767px) {
  .slide-art {
    width: 150px;
    height: 150px;
    right: -30px;
    bottom: -30px;
    top: auto;
    transform: none;
    opacity: 0.7;
  }

  .art-dot--1 { width: 30px; height: 30px; }
  .art-dot--2 { width: 22px; height: 22px; }
  .art-dot--3 { width: 14px; height: 14px; }

  .post-card {
    flex-direction: column;
    gap: 0.9rem;
  }

  .post-cover {
    width: 100%;
    height: 120px;
  }
}

/* 移动端：搜索框收成图标，点击后由 JS 展开为可输入的胶囊 */
@media (max-width: 639px) {
  .search-form {
    width: 46px;
    padding: 0 0.6rem;
  }

  .search-form .search-input,
  .search-form .search-clear {
    display: none;
  }

  .search-form.is-expanded {
    width: min(72vw, 260px);
  }

  .search-form.is-expanded .search-input {
    display: block;
  }

  .search-form.is-expanded .search-clear {
    display: grid;
  }

  /* 展开时让面板撑满可视宽度，方便点选结果 */
  .search-panel {
    width: min(88vw, 340px);
  }
}

/* 极窄屏：隐藏用户入口胶囊，避免导航拥挤（登录入口在抽屉菜单中） */
@media (max-width: 400px) {
  .btn-user {
    display: none;
  }
}

/* —— 尊重系统的「减少动态效果」偏好 —— */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .js .reveal {
    opacity: 1;
    transform: none;
  }

  /* 持续下落的雨会对前庭敏感用户造成干扰，直接关闭 */
  .rain {
    display: none;
  }
}

/* —— 打印样式：去掉装饰，保留内容 —— */
@media print {
  .nav-bar,
  .carousel-arrow,
  .carousel-footer,
  .back-to-top,
  .side-card,
  .footer,
  .rain,
  .toast {
    display: none !important;
  }

  body {
    background: #fff;
  }
}