/* ============================================================
   ux-enhance.css · 北创大为站群统一体验增强层
   适用：www.evtol.bj.cn / www.aam.bj.cn / www.jszn.net.cn
   主题自适应：JS 会按宿主页面背景明度写 html[data-ux-theme=light|dark]
   说明：所有类名以 ux- 前缀，避免与站点既有样式冲突
   ============================================================ */

/* ---------- 主题变量 ---------- */
html {
  --ux-accent: #3fb3d9;
  --ux-accent-2: #7dd1ef;
  --ux-primary: #002890;
  --ux-radius: 14px;
  --ux-shadow: 0 18px 44px rgba(0, 12, 48, .28);

  /* 浅色（默认） */
  --ux-surface: rgba(255, 255, 255, .96);
  --ux-surface-2: #f3f7ff;
  --ux-fg: #0a1a40;
  --ux-fg-muted: #52608a;
  --ux-line: rgba(0, 40, 144, .12);
  --ux-line-strong: rgba(0, 40, 144, .22);
  --ux-chip: rgba(0, 40, 144, .06);
  --ux-overlay: rgba(6, 18, 48, .52);
}

html[data-ux-theme="dark"] {
  --ux-surface: rgba(12, 28, 70, .96);
  --ux-surface-2: rgba(204, 226, 255, .05);
  --ux-fg: #eef4ff;
  --ux-fg-muted: #a9bde4;
  --ux-line: rgba(255, 255, 255, .14);
  --ux-line-strong: rgba(63, 179, 217, .42);
  --ux-chip: rgba(204, 226, 255, .08);
  --ux-overlay: rgba(1, 5, 26, .68);
  --ux-shadow: 0 18px 44px rgba(0, 5, 26, .6);
}

/* ---------- 阅读进度条 ---------- */
.ux-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  z-index: 9990;
  background: linear-gradient(90deg, var(--ux-primary) 0%, var(--ux-accent) 55%, var(--ux-accent-2) 100%);
  box-shadow: 0 0 12px rgba(63, 179, 217, .55);
  transition: opacity .3s;
  pointer-events: none;
}

/* ---------- 右侧悬浮操作轨道 ---------- */
.ux-rail {
  position: fixed;
  right: 20px;
  bottom: 26px;
  z-index: 9985;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  font-family: "PingFang SC", "Microsoft YaHei", -apple-system, sans-serif;
}

/* aam 站已有 contact-fab（右下角 24px，直径 60）→ 整体上移 */
html.ux-has-fab .ux-rail { bottom: 104px; }
html.ux-has-fab .ux-toast { bottom: 190px; }

.ux-rail-btn {
  position: relative;
  width: 46px;
  height: 46px;
  border: 1px solid var(--ux-line);
  border-radius: 14px;
  background: var(--ux-surface);
  color: var(--ux-fg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: var(--ux-shadow);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform .2s cubic-bezier(.4, 0, .2, 1), box-shadow .2s, border-color .2s, background .2s;
  padding: 0;
}

.ux-rail-btn:hover {
  transform: translateY(-2px);
  border-color: var(--ux-line-strong);
  box-shadow: 0 22px 50px rgba(0, 12, 48, .3), 0 0 0 4px rgba(63, 179, 217, .12);
}

.ux-rail-btn:active { transform: scale(.94); }
.ux-rail-btn svg { width: 20px; height: 20px; display: block; }
.ux-rail-btn::after {
  content: attr(data-ux-tip);
  position: absolute;
  right: calc(100% + 10px);
  top: 50%;
  transform: translateY(-50%) translateX(6px);
  white-space: nowrap;
  font-size: 12.5px;
  line-height: 1;
  padding: 7px 10px;
  border-radius: 8px;
  background: var(--ux-fg);
  color: var(--ux-surface);
  opacity: 0;
  pointer-events: none;
  transition: opacity .18s, transform .18s;
}
.ux-rail-btn:hover::after { opacity: .95; transform: translateY(-50%) translateX(0); }

/* 回到顶部：环形进度 */
.ux-top { overflow: visible; }
.ux-top .ux-ring {
  position: absolute;
  inset: -3px;
  width: calc(100% + 6px);
  height: calc(100% + 6px);
  transform: rotate(-90deg);
  pointer-events: none;
}
.ux-top .ux-ring circle {
  fill: none;
  stroke: var(--ux-accent);
  stroke-width: 2.5;
  stroke-linecap: round;
  opacity: .85;
}
.ux-top.ux-off { opacity: 0; visibility: hidden; transform: translateY(10px); }

/* 搜索入口轻微呼吸提示 */
.ux-rail-btn.ux-hint { animation: uxHint 2.6s ease-in-out 3; }
@keyframes uxHint {
  0%, 100% { box-shadow: var(--ux-shadow); }
  50% { box-shadow: 0 0 0 8px rgba(63, 179, 217, .16), var(--ux-shadow); }
}

/* ---------- 轻提示 ---------- */
.ux-toast {
  position: fixed;
  right: 82px;
  bottom: 34px;
  z-index: 9995;
  padding: 11px 16px;
  border-radius: 12px;
  background: var(--ux-fg);
  color: var(--ux-surface);
  font-size: 13.5px;
  line-height: 1.4;
  box-shadow: 0 16px 40px rgba(0, 10, 40, .34);
  opacity: 0;
  transform: translateY(8px);
  transition: opacity .22s, transform .22s;
  pointer-events: none;
  max-width: 70vw;
}
.ux-toast.ux-on { opacity: 1; transform: translateY(0); }

/* ---------- 遮罩 ---------- */
.ux-mask {
  position: fixed;
  inset: 0;
  z-index: 9996;
  background: var(--ux-overlay);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  visibility: hidden;
  transition: opacity .22s, visibility .22s;
}
.ux-mask.ux-on { opacity: 1; visibility: visible; }

/* ---------- 站内搜索 ---------- */
.ux-search {
  position: fixed;
  left: 50%;
  top: 10vh;
  transform: translateX(-50%) translateY(-14px) scale(.98);
  width: min(720px, 92vw);
  max-height: 76vh;
  z-index: 9998;
  display: flex;
  flex-direction: column;
  border-radius: 20px;
  background: var(--ux-surface);
  border: 1px solid var(--ux-line);
  box-shadow: 0 40px 100px rgba(0, 8, 32, .45);
  opacity: 0;
  visibility: hidden;
  overflow: hidden;
  transition: opacity .22s, transform .22s, visibility .22s;
  color: var(--ux-fg);
}
.ux-search.ux-on {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0) scale(1);
}

.ux-search-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 18px;
  border-bottom: 1px solid var(--ux-line);
  background: linear-gradient(180deg, rgba(63, 179, 217, .1), transparent);
}
.ux-search-head svg { width: 20px; height: 20px; color: var(--ux-accent); flex: none; }
.ux-search-input {
  flex: 1;
  border: 0;
  outline: 0;
  background: transparent;
  font-size: 16.5px;
  color: var(--ux-fg);
  font-family: inherit;
  min-width: 0;
}
.ux-search-input::placeholder { color: var(--ux-fg-muted); opacity: .75; }
.ux-kbd {
  flex: none;
  font-size: 11.5px;
  padding: 3px 7px;
  border-radius: 6px;
  border: 1px solid var(--ux-line);
  background: var(--ux-chip);
  color: var(--ux-fg-muted);
  letter-spacing: .04em;
}

.ux-search-body { overflow-y: auto; padding: 8px; overscroll-behavior: contain; }

.ux-search-hint {
  padding: 14px 12px 16px;
  font-size: 13px;
  color: var(--ux-fg-muted);
  line-height: 1.9;
}
.ux-chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 10px; }
.ux-chip {
  border: 1px solid var(--ux-line);
  background: var(--ux-chip);
  color: var(--ux-fg);
  border-radius: 999px;
  padding: 6px 13px;
  font-size: 13px;
  cursor: pointer;
  transition: all .18s;
  font-family: inherit;
}
.ux-chip:hover { border-color: var(--ux-accent); color: var(--ux-accent); transform: translateY(-1px); }

.ux-res {
  display: block;
  padding: 11px 12px;
  border-radius: 12px;
  border: 1px solid transparent;
  transition: background .15s, border-color .15s;
  cursor: pointer;
}
.ux-res:hover, .ux-res.ux-cur { background: var(--ux-chip); border-color: var(--ux-line-strong); }
.ux-res-t {
  font-size: 15px;
  font-weight: 600;
  line-height: 1.5;
  margin-bottom: 3px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.ux-res-t em, .ux-res-s em { font-style: normal; color: var(--ux-accent); font-weight: 800; }
.ux-res-m { font-size: 12.5px; color: var(--ux-fg-muted); display: flex; gap: 10px; flex-wrap: wrap; }
.ux-res-m span {
  padding: 1px 8px;
  border-radius: 999px;
  background: var(--ux-chip);
  border: 1px solid var(--ux-line);
}
.ux-res-s {
  font-size: 13px;
  color: var(--ux-fg-muted);
  margin-top: 4px;
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.ux-search-foot {
  padding: 9px 16px;
  border-top: 1px solid var(--ux-line);
  font-size: 12px;
  color: var(--ux-fg-muted);
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

/* ---------- 分享面板 ---------- */
.ux-share {
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%) scale(.94);
  width: min(420px, 92vw);
  z-index: 9998;
  border-radius: 20px;
  background: var(--ux-surface);
  border: 1px solid var(--ux-line);
  box-shadow: 0 40px 100px rgba(0, 8, 32, .45);
  padding: 22px;
  color: var(--ux-fg);
  opacity: 0;
  visibility: hidden;
  transition: opacity .22s, transform .22s, visibility .22s;
}
.ux-share.ux-on { opacity: 1; visibility: visible; transform: translate(-50%, -50%) scale(1); }
.ux-share h4 { font-size: 17px; margin-bottom: 4px; font-weight: 800; }
.ux-share p { font-size: 13px; color: var(--ux-fg-muted); margin-bottom: 16px; }
.ux-share-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; }
.ux-share-btn {
  border: 1px solid var(--ux-line);
  background: var(--ux-chip);
  border-radius: 14px;
  padding: 12px 6px 10px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 7px;
  cursor: pointer;
  font-size: 12.5px;
  color: var(--ux-fg);
  font-family: inherit;
  transition: all .18s;
}
.ux-share-btn:hover { transform: translateY(-2px); border-color: var(--ux-accent); }
.ux-share-btn svg { width: 22px; height: 22px; }
.ux-share-link {
  margin-top: 14px;
  display: flex;
  gap: 8px;
}
.ux-share-link input {
  flex: 1;
  min-width: 0;
  border: 1px solid var(--ux-line);
  border-radius: 10px;
  padding: 9px 12px;
  font-size: 13px;
  background: var(--ux-surface-2);
  color: var(--ux-fg-muted);
  font-family: inherit;
  outline: none;
}
.ux-share-link button {
  flex: none;
  border: 0;
  border-radius: 10px;
  padding: 0 18px;
  background: linear-gradient(135deg, var(--ux-primary), var(--ux-accent));
  color: #fff;
  font-size: 13.5px;
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
}
.ux-qr {
  margin: 16px auto 0;
  width: 168px;
  height: 168px;
  border-radius: 12px;
  background: #fff;
  padding: 8px;
  display: none;
}
.ux-qr.ux-on { display: block; }
.ux-qr canvas, .ux-qr img { width: 100%; height: 100%; display: block; image-rendering: pixelated; }
.ux-qr-tip { text-align: center; font-size: 12.5px; color: var(--ux-fg-muted); margin-top: 8px; display: none; }
.ux-qr-tip.ux-on { display: block; }

/* ---------- 相关阅读 ---------- */
.ux-rel {
  margin: 40px 0 8px;
  padding: 24px 22px;
  border-radius: 18px;
  border: 1px solid var(--ux-line);
  background: var(--ux-surface-2);
}
.ux-rel-h {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 16px;
  font-weight: 800;
  margin-bottom: 14px;
  color: var(--ux-fg);
}
.ux-rel-h::before {
  content: "";
  width: 4px;
  height: 17px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--ux-primary), var(--ux-accent));
}
.ux-rel-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.ux-rel-a {
  display: block;
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid var(--ux-line);
  background: var(--ux-surface);
  transition: all .2s;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ux-fg);
}
.ux-rel-a:hover {
  transform: translateY(-2px);
  border-color: var(--ux-accent);
  box-shadow: 0 14px 32px rgba(0, 12, 48, .16);
}
.ux-rel-a b { display: block; font-weight: 600; margin-bottom: 5px; }
.ux-rel-a span { font-size: 12.5px; color: var(--ux-fg-muted); }

/* ---------- 资讯页侧栏：热门排行 / 标签云 ---------- */
.ux-hot {
  border: 1px solid var(--ux-line);
  border-radius: 18px;
  background: var(--ux-surface-2);
  padding: 22px 20px;
}
.ux-hot-h {
  font-size: 16px;
  font-weight: 800;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ux-fg);
}
.ux-hot-h::before {
  content: "";
  width: 4px;
  height: 17px;
  border-radius: 2px;
  background: linear-gradient(180deg, var(--ux-primary), var(--ux-accent));
}
.ux-hot-list { display: flex; flex-direction: column; gap: 2px; counter-reset: uxhot; }
.ux-hot-a {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 10px 8px;
  border-radius: 10px;
  transition: background .18s;
  color: var(--ux-fg);
  font-size: 14px;
  line-height: 1.55;
}
.ux-hot-a:hover { background: var(--ux-chip); }
.ux-hot-a::before {
  counter-increment: uxhot;
  content: counter(uxhot);
  flex: none;
  width: 21px;
  height: 21px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--ux-chip);
  color: var(--ux-fg-muted);
  margin-top: 2px;
}
.ux-hot-a:nth-child(1)::before { background: #e5484d; color: #fff; }
.ux-hot-a:nth-child(2)::before { background: #f76808; color: #fff; }
.ux-hot-a:nth-child(3)::before { background: #ffb224; color: #fff; }

/* ---------- 正文目录（TOC） ---------- */
.ux-toc {
  position: fixed;
  right: 22px;
  top: 50%;
  transform: translateY(-50%);
  width: 210px;
  max-height: 62vh;
  overflow-y: auto;
  z-index: 9980;
  padding: 16px 14px;
  border-radius: 16px;
  border: 1px solid var(--ux-line);
  background: var(--ux-surface);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  box-shadow: var(--ux-shadow);
  opacity: 0;
  visibility: hidden;
  transition: opacity .25s, visibility .25s;
}
.ux-toc.ux-on { opacity: 1; visibility: visible; }
.ux-toc-t {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .1em;
  color: var(--ux-fg-muted);
  margin-bottom: 10px;
  text-transform: uppercase;
}
.ux-toc a {
  display: block;
  font-size: 13px;
  line-height: 1.5;
  padding: 6px 9px;
  border-radius: 8px;
  border-left: 2px solid transparent;
  color: var(--ux-fg-muted);
  transition: all .18s;
}
.ux-toc a:hover { color: var(--ux-accent); background: var(--ux-chip); }
.ux-toc a.ux-on { color: var(--ux-accent); border-left-color: var(--ux-accent); background: var(--ux-chip); font-weight: 700; }
.ux-toc a.ux-lv3 { padding-left: 20px; font-size: 12.5px; }
@media (max-width: 1500px) { .ux-toc { display: none; } }

/* ---------- 滚动进入动效 ---------- */
.ux-js [data-ux-reveal] {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity .7s cubic-bezier(.22, 1, .36, 1), transform .7s cubic-bezier(.22, 1, .36, 1);
  will-change: opacity, transform;
}
.ux-js [data-ux-reveal].ux-in { opacity: 1; transform: none; }

/* ---------- 图片淡入 ---------- */
.ux-js img[loading="lazy"] { transition: opacity .5s ease; }
.ux-js img[loading="lazy"].ux-img-pending { opacity: 0; }
.ux-js img[loading="lazy"].ux-img-done { opacity: 1; }

/* ---------- 关键数字滚动 ---------- */
[data-ux-count] { font-variant-numeric: tabular-nums; }

/* ---------- 骨架占位（资讯列表图） ---------- */
.ux-skel {
  background: linear-gradient(100deg, var(--ux-chip) 30%, var(--ux-line) 50%, var(--ux-chip) 70%);
  background-size: 220% 100%;
  animation: uxSkel 1.3s linear infinite;
}
@keyframes uxSkel { from { background-position: 220% 0; } to { background-position: -20% 0; } }

/* ---------- 常见问题（FAQ 手风琴） ---------- */
.ux-faq {
  margin-top: 8px;
}
.ux-faq-h {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 18px;
}
.ux-faq-h b {
  font-size: clamp(20px, 2.4vw, 26px);
  font-weight: 800;
  color: var(--ux-fg);
}
.ux-faq-h span {
  font-size: 12.5px;
  letter-spacing: .12em;
  color: var(--ux-fg-muted);
  text-transform: uppercase;
}
.ux-faq-item {
  border: 1px solid var(--ux-line);
  border-radius: 14px;
  background: var(--ux-surface-2);
  padding: 0 18px;
  margin-bottom: 10px;
  transition: border-color .2s, background .2s;
}
.ux-faq-item[open] {
  border-color: var(--ux-line-strong);
  background: var(--ux-surface);
}
.ux-faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: 16px 0;
  font-size: 15.5px;
  font-weight: 700;
  color: var(--ux-fg);
  display: flex;
  align-items: center;
  gap: 12px;
  line-height: 1.5;
}
.ux-faq-item summary::-webkit-details-marker { display: none; }
.ux-faq-item summary::before {
  content: "Q";
  flex: none;
  width: 24px;
  height: 24px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--ux-primary), var(--ux-accent));
  color: #fff;
  font-size: 13px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
}
.ux-faq-item summary::after {
  content: "";
  flex: none;
  margin-left: auto;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--ux-fg-muted);
  border-bottom: 2px solid var(--ux-fg-muted);
  transform: rotate(45deg);
  transition: transform .22s;
}
.ux-faq-item[open] summary::after { transform: rotate(225deg); }
.ux-faq-a {
  padding: 0 0 18px 36px;
  font-size: 14.5px;
  line-height: 1.85;
  color: var(--ux-fg-muted);
}
.ux-faq-a a { color: var(--ux-accent); font-weight: 600; text-decoration: none; border-bottom: 1px solid currentColor; }
.ux-faq-a a:hover { color: var(--ux-primary); }

/* ---------- 视频封面 ---------- */
.video-cover { position: relative; overflow: hidden; }
.video-cover .video-cover-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
  transition: transform .45s cubic-bezier(.22, 1, .36, 1);
}
.video-card:hover .video-cover-img { transform: scale(1.06); }

/* ---------- 移动端适配 ---------- */
@media (max-width: 720px) {
  .ux-rail { right: 12px; bottom: 16px; gap: 8px; }
  html.ux-has-fab .ux-rail { bottom: 92px; }
  .ux-rail-btn { width: 42px; height: 42px; border-radius: 12px; }
  .ux-rail-btn::after { display: none; }
  .ux-search { top: 4vh; width: 94vw; max-height: 84vh; border-radius: 16px; }
  .ux-rel-list { grid-template-columns: 1fr; }
  .ux-share-grid { grid-template-columns: repeat(4, 1fr); gap: 8px; }
  .ux-toast { right: 16px; left: 16px; max-width: none; text-align: center; }
}

@media print, (prefers-reduced-motion: reduce) {
  .ux-js [data-ux-reveal] { opacity: 1 !important; transform: none !important; }
  .ux-rail, .ux-progress, .ux-toc, .ux-toast { display: none !important; }
}