/*
 * df-skin.css - 当发网「季节/春节」换肤系统（全站皮肤层）
 * 版本：1.0
 * 说明：
 *   1) 五套季节色板经 theme-preview.html 目验锁定，通过 html[data-skin="…"] 覆写两套 CSS 变量：
 *      - 首页 index.css 的 --color-*（语义化命名体系）
 *      - 各频道/内容/错误页的 --*-color（频道模板命名体系）
 *      未声明"data-skin"时本文件不改变站点任何外观（优雅降级）。
 *   2) 附带的 3 条非破坏性规则（h1 白字、副标语去透明度、阅读进度条渐变终点=季节装饰亮色）
 *      与 4b. 氛围动效容器 .df-ambient、5. 悬浮换肤面板 .df-skin-* 的 UI 样式。
 * 作者：当发网
 * 版权所有：Dangfa.com
 */

/* ============================================================ */
/* 1. 五套季节色板（值锁定自 theme-preview.html v1.1 验收版本）   */
/* ============================================================ */
/* 春 · 翡翠绿（立春 → 立夏） */
html[data-skin="spring"] {
  --primary-color: #0A6B50; --primary-dark: #064A37;
  --secondary-color: #0D8259; --accent-color: #F3E8C2;
  --dark-color: #0A2E24; --light-color: #E6F1EA;
  --gray-light: #EFF6F1; --gray-medium: #CCE0D3;
  --color-primary: #0A6B50; --color-primary-dark: #064A37;
  --color-secondary: #0D8259; --color-accent: #F3E8C2;
  --color-dark: #0A2E24; --color-light: #E6F1EA;
  --color-gray-light: #EFF6F1; --color-gray-medium: #CCE0D3;
  --color-text-primary: #26282A; --color-text-secondary: #5B675F;
  --color-text-on-primary: #ffffff; --color-text-on-dark: #E6F1EA;
  --color-card-bg: #F3E8C2; --color-card-text: #26282A;
  --color-card-title: #0A6B50; --color-card-border: #CCE0D3;
  --skin-bright: #35C48C;
}

/* 夏 · 深海蓝（立夏 → 立秋） */
html[data-skin="summer"] {
  --primary-color: #0F5F8A; --primary-dark: #0A405F;
  --secondary-color: #1A6D9C; --accent-color: #F2E9C9;
  --dark-color: #0A2A3F; --light-color: #E8F2F8;
  --gray-light: #EFF6FA; --gray-medium: #CBDDE8;
  --color-primary: #0F5F8A; --color-primary-dark: #0A405F;
  --color-secondary: #1A6D9C; --color-accent: #F2E9C9;
  --color-dark: #0A2A3F; --color-light: #E8F2F8;
  --color-gray-light: #EFF6FA; --color-gray-medium: #CBDDE8;
  --color-text-primary: #222B31; --color-text-secondary: #57656F;
  --color-text-on-primary: #ffffff; --color-text-on-dark: #E8F2F8;
  --color-card-bg: #F2E9C9; --color-card-text: #222B31;
  --color-card-title: #0F5F8A; --color-card-border: #CBDDE8;
  --skin-bright: #39C0E8;
}

/* 秋 · 栗枫红棕（立秋 → 立冬） */
html[data-skin="autumn"] {
  --primary-color: #9C4A23; --primary-dark: #6B3115;
  --secondary-color: #8E3B1F; --accent-color: #F7E6BC;
  --dark-color: #3A2010; --light-color: #F7ECDC;
  --gray-light: #FAF3E8; --gray-medium: #E6D3BA;
  --color-primary: #9C4A23; --color-primary-dark: #6B3115;
  --color-secondary: #8E3B1F; --color-accent: #F7E6BC;
  --color-dark: #3A2010; --color-light: #F7ECDC;
  --color-gray-light: #FAF3E8; --color-gray-medium: #E6D3BA;
  --color-text-primary: #2B2620; --color-text-secondary: #6B5F50;
  --color-text-on-primary: #ffffff; --color-text-on-dark: #F7ECDC;
  --color-card-bg: #F7E6BC; --color-card-text: #2B2620;
  --color-card-title: #9C4A23; --color-card-border: #E6D3BA;
  --skin-bright: #F2A05C;
}

/* 冬 · 深钢青蓝（立冬 → 次年立春） */
html[data-skin="winter"] {
  --primary-color: #245A80; --primary-dark: #123C57;
  --secondary-color: #2E6B8F; --accent-color: #ECEBD9;
  --dark-color: #0E2233; --light-color: #EAF2F6;
  --gray-light: #F2F6F8; --gray-medium: #C9DCE5;
  --color-primary: #245A80; --color-primary-dark: #123C57;
  --color-secondary: #2E6B8F; --color-accent: #ECEBD9;
  --color-dark: #0E2233; --color-light: #EAF2F6;
  --color-gray-light: #F2F6F8; --color-gray-medium: #C9DCE5;
  --color-text-primary: #222A30; --color-text-secondary: #56656E;
  --color-text-on-primary: #ffffff; --color-text-on-dark: #EAF2F6;
  --color-card-bg: #ECEBD9; --color-card-text: #222A30;
  --color-card-title: #245A80; --color-card-border: #C9DCE5;
  --skin-bright: #9BD6EE;
}

/* 春节 · 绛红（除夕 00:00 → 正月十六 00:00，优先于四季） */
html[data-skin="cny"] {
  --primary-color: #A8242C; --primary-dark: #7A141C;
  --secondary-color: #A93A40; --accent-color: #F9E4AE;
  --dark-color: #460A0F; --light-color: #FBEED6;
  --gray-light: #FCF5EA; --gray-medium: #E8D3B4;
  --color-primary: #A8242C; --color-primary-dark: #7A141C;
  --color-secondary: #A93A40; --color-accent: #F9E4AE;
  --color-dark: #460A0F; --color-light: #FBEED6;
  --color-gray-light: #FCF5EA; --color-gray-medium: #E8D3B4;
  --color-text-primary: #2B211F; --color-text-secondary: #6E5B55;
  --color-text-on-primary: #ffffff; --color-text-on-dark: #FBEED6;
  --color-card-bg: #F9E4AE; --color-card-text: #2B211F;
  --color-card-title: #A8242C; --color-card-border: #E8D3B4;
  --skin-bright: #FFD36B;
}

/* ============================================================ */
/* 2. 换肤伴随的三条非破坏性规则（预览验收要求）                 */
/* ============================================================ */
/* 频道/内容页 h1 由原 accent 色改为白色，与 5 套主色均保持 AA */
html[data-skin] header h1 {
  color: #ffffff;
}

/* 频道副标语取消原 0.85/0.9 透明度，保证浅金副标语对比度达标 */
html[data-skin] header p {
  opacity: 1;
}

/* 阅读进度条：渐变终点由固定粉色改为“季节装饰亮色 --skin-bright”
   （本规则同时覆盖 5 个频道 CSS 与 Bootstrap 频道进度条的既有渐变） */
html[data-skin] .reading-progress {
  background: linear-gradient(90deg, var(--primary-color), var(--skin-bright));
}

/* ============================================================ */
/* 3. 氛围动效容器（由 js/df-skin.js 程序化建立于页头/留白区内） */
/*    粒子仅绘制在这些容器中，正文与教学演示区天然无覆盖       */
/* ============================================================ */
.df-ambient {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.df-ambient canvas {
  display: block;
  width: 100%;
  height: 100%;
}

/* ============================================================ */
/* 4. 悬浮换肤面板 UI                                           */
/* ============================================================ */
.df-skin-fab {
  position: fixed;
  left: 16px;
  bottom: 16px;
  width: 52px;
  height: 52px;
  margin: 0;
  padding: 0;
  border: 3px solid #ffffff;
  border-radius: 50%;
  background: conic-gradient(#0A6B50 0 25%, #0F5F8A 25% 50%, #9C4A23 50% 75%, #A8242C 75%);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.35);
  cursor: pointer;
  z-index: 2147483000;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  -webkit-tap-highlight-color: transparent;
}

.df-skin-fab:hover,
.df-skin-fab:focus-visible {
  transform: scale(1.08);
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.45);
}

.df-skin-fab:focus-visible {
  outline: 3px solid #e8d8b0;
  outline-offset: 3px;
}

.df-skin-fab[aria-expanded="true"] {
  transform: none;
}

.df-skin-fab::after {
  content: "";
  position: absolute;
  inset: 6px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.92);
  box-shadow: inset 0 0 0 1px rgba(0, 0, 0, 0.08);
}

.df-skin-fab .df-fab-glyph {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.15rem;
  font-size: 0.8rem;
  line-height: 1;
  z-index: 1;
}

.df-skin-panel {
  position: fixed;
  left: 16px;
  bottom: 78px;
  width: 318px;
  max-width: calc(100vw - 32px);
  max-height: min(74vh, 560px);
  overflow-y: auto;
  background: var(--color-white, #ffffff);
  color: var(--color-text-primary, #333333);
  border: 1px solid var(--color-gray-medium, #e0e0e0);
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
  z-index: 2147483001;
  display: none;
  font-size: 0.85rem;
}

.df-skin-panel[hidden] {
  display: none;
}

.df-skin-panel.df-open {
  display: block;
  animation: df-panel-in 0.18s ease;
}

@keyframes df-panel-in {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: none; }
}

.df-skin-panel .df-skin-head {
  background: var(--color-primary, #82255e);
  color: var(--color-text-on-primary, #ffffff);
  padding: 12px 14px;
  border-radius: 11px 11px 0 0;
}

.df-skin-panel .df-skin-head h2 {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
  color: #ffffff;
}

.df-skin-panel .df-skin-head p {
  margin: 4px 0 0;
  font-size: 0.75rem;
  opacity: 0.92;
  color: #ffffff;
}

.df-skin-panel .df-skin-body {
  padding: 12px 14px 14px;
}

.df-skin-panel .df-skin-group {
  margin-bottom: 10px;
}

.df-skin-panel .df-skin-group > .df-skin-label {
  display: block;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-text-secondary, #595959);
  margin-bottom: 6px;
  letter-spacing: 0.02em;
}

.df-skin-modes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
}

.df-skin-modes button,
.df-skin-opts button {
  font: inherit;
  border: 1px solid var(--color-gray-medium, #e0e0e0);
  background: var(--color-white, #ffffff);
  color: var(--color-text-primary, #333);
  border-radius: 8px;
  padding: 7px 4px;
  cursor: pointer;
  transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.df-skin-modes button:hover,
.df-skin-modes button:focus-visible,
.df-skin-opts button:hover,
.df-skin-opts button:focus-visible {
  border-color: var(--color-primary, #82255e);
}

.df-skin-modes button.df-active {
  background: var(--color-primary, #82255e);
  border-color: var(--color-primary, #82255e);
  color: #ffffff;
  font-weight: 700;
}

.df-skin-panel .df-skin-status {
  font-size: 0.75rem;
  line-height: 1.55;
  color: var(--color-text-secondary, #595959);
  background: var(--color-gray-light, #f5f5f5);
  border: 1px solid var(--color-gray-medium, #e0e0e0);
  border-radius: 8px;
  padding: 8px 10px;
  margin-bottom: 10px;
}

.df-skin-panel .df-skin-status b {
  color: var(--color-primary, #82255e);
  font-weight: 700;
}

.df-skin-opts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
}

.df-skin-opts button {
  display: flex;
  align-items: center;
  gap: 6px;
  justify-content: flex-start;
  padding: 7px 8px;
  text-align: left;
}

.df-skin-opts button .df-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex: none;
  border: 1px solid rgba(0, 0, 0, 0.2);
}

.df-skin-opts button.df-active {
  background: var(--color-primary, #82255e);
  border-color: var(--color-primary, #82255e);
  color: #ffffff;
}

.df-skin-opts button.df-now::after {
  content: "本季";
  font-size: 0.65rem;
  opacity: 0.85;
  margin-left: auto;
}

.df-skin-opts button.df-now.df-active::after {
  color: #ffffff;
}

.df-skin-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 8px 0;
  border-top: 1px solid var(--color-gray-medium, #e0e0e0);
}

.df-skin-row span {
  font-weight: 600;
  font-size: 0.8rem;
  color: var(--color-text-primary, #333);
}

.df-skin-row small {
  display: block;
  font-weight: 400;
  color: var(--color-text-secondary, #595959);
  margin-top: 2px;
}

/* 动效开关（无障碍开关） */
.df-switch {
  position: relative;
  width: 40px;
  height: 22px;
  flex: none;
}

.df-switch input {
  position: absolute;
  opacity: 0;
  width: 100%;
  height: 100%;
  margin: 0;
  cursor: pointer;
}

.df-switch .df-track {
  position: absolute;
  inset: 0;
  background: var(--color-gray-medium, #c0c0c0);
  border-radius: 11px;
  transition: background 0.2s ease;
}

.df-switch .df-track::before {
  content: "";
  position: absolute;
  top: 2px;
  left: 2px;
  width: 18px;
  height: 18px;
  background: #ffffff;
  border-radius: 50%;
  transition: transform 0.2s ease;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

.df-switch input:checked + .df-track {
  background: var(--color-primary, #82255e);
}

.df-switch input:checked + .df-track::before {
  transform: translateX(18px);
}

.df-switch input:focus-visible + .df-track {
  outline: 2px solid var(--color-primary, #82255e);
  outline-offset: 2px;
}

.df-skin-panel .df-skin-note {
  margin: 8px 0 0;
  font-size: 0.72rem;
  line-height: 1.5;
  color: var(--color-text-secondary, #595959);
}

.df-skin-panel .df-skin-foot {
  padding: 8px 14px;
  border-top: 1px solid var(--color-gray-medium, #e0e0e0);
  text-align: right;
}

.df-skin-panel .df-skin-foot a {
  color: var(--color-primary, #82255e);
  font-size: 0.72rem;
  text-decoration: none;
}

/* 打印与减弱动效：隐藏悬浮面板并让粒子静止（JS 侧另有 prefers-reduced-motion 检测） */
@media print {
  .df-skin-fab,
  .df-skin-panel {
    display: none !important;
  }
  .df-ambient {
    display: none !important;
  }
}

@media (prefers-reduced-motion: reduce) {
  .df-skin-fab {
    transition: none;
  }
}

/* 深色系统偏好：首页卡片在深色模式下的少量文字交互色需显式对齐季节色板
   （避免 index.css 深色 media 覆盖出的浅字悬停色在换肤后失去对比） */
@media (prefers-color-scheme: dark) {
  html[data-skin] .tech-card .read-more {
    color: var(--color-primary);
  }
  html[data-skin] .tech-card:hover .read-more,
  html[data-skin] .tech-card:focus-within .read-more {
    color: var(--color-dark);
  }
  html[data-skin] .nav-link:hover,
  html[data-skin] .nav-link:focus-visible {
    color: var(--color-primary-dark);
  }
}