/* ============================================================
 * 物理交互动画课堂 · 全站共享样式
 * 移动优先；核心断点 320 / 768 / 1200
 * ============================================================ */
* { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --bg: #0a1120;
  --bg-soft: #0e1729;
  --card: #121d33;
  --card-2: #16243f;
  --line: #233656;
  --txt: #eaf1fb;
  --txt-2: #9db0cc;
  --txt-3: #6b7f9e;
  --amber: #f5b244;
  --cyan: #5cc9f5;
  --green: #43d39e;
  --red: #ff7a7a;
  --purple: #b79bff;
  --radius: 16px;
  --shadow: 0 14px 40px rgba(0, 0, 0, .35);
  --tap: 44px;
}
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;
  background:
    radial-gradient(900px 420px at 80% -8%, rgba(92, 201, 245, .10), transparent 60%),
    radial-gradient(700px 380px at -10% 0%, rgba(245, 178, 68, .08), transparent 55%),
    var(--bg);
  color: var(--txt);
  line-height: 1.65;
  min-height: 100vh;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img, iframe { border: 0; display: block; }
button { font-family: inherit; cursor: pointer; }
:focus-visible { outline: 2px solid var(--cyan); outline-offset: 2px; }

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 16px; }

/* ---------- 顶部导航 ---------- */
.topnav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(10, 17, 32, .88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.topnav .inner {
  max-width: 1200px; margin: 0 auto; padding: 0 16px;
  height: 56px; display: flex; align-items: center; gap: 14px;
}
.brand { display: flex; align-items: center; gap: 9px; font-weight: 700; font-size: 16px; white-space: nowrap; }
.brand .logo {
  width: 30px; height: 30px; border-radius: 9px; flex: none;
  display: grid; place-items: center; font-size: 17px;
  background: linear-gradient(135deg, var(--amber), #e0881b);
  box-shadow: 0 4px 14px rgba(245, 178, 68, .35);
}
.brand small { color: var(--txt-3); font-weight: 500; font-size: 11px; letter-spacing: 1px; }
.nav-links { margin-left: auto; display: flex; align-items: center; gap: 4px; }
.nav-links a {
  padding: 8px 12px; border-radius: 10px; font-size: 14px; color: var(--txt-2);
  min-height: 40px; display: inline-flex; align-items: center; white-space: nowrap;
  transition: background .15s, color .15s;
}
.nav-links a:hover { color: var(--txt); background: var(--card-2); }
.nav-links a.active { color: var(--amber); background: rgba(245, 178, 68, .12); }

/* ---------- 首页 Hero ---------- */
.hero { padding: 40px 0 26px; text-align: center; }
.hero h1 { font-size: 27px; line-height: 1.3; letter-spacing: .5px; }
.hero h1 em { font-style: normal; color: var(--amber); }
.hero p.sub { color: var(--txt-2); font-size: 14.5px; margin: 12px auto 0; max-width: 620px; }
.searchbox { position: relative; max-width: 600px; margin: 22px auto 0; }
.searchbox input {
  width: 100%; height: 50px; border-radius: 14px;
  border: 1px solid var(--line); background: var(--card);
  color: var(--txt); font-size: 15px; padding: 0 88px 0 46px;
  transition: border-color .15s, box-shadow .15s;
}
.searchbox input::placeholder { color: var(--txt-3); }
.searchbox input:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(92, 201, 245, .15); outline: none; }
.searchbox .ico { position: absolute; left: 16px; top: 50%; transform: translateY(-50%); font-size: 17px; pointer-events: none; }
.searchbox button {
  position: absolute; right: 7px; top: 7px; height: 36px; padding: 0 16px;
  border: 0; border-radius: 10px; font-size: 14px; font-weight: 600;
  background: linear-gradient(135deg, var(--amber), #e0881b); color: #1a1206;
}
.search-suggest {
  position: absolute; left: 0; right: 0; top: 58px; z-index: 40; text-align: left;
  background: var(--card-2); border: 1px solid var(--line); border-radius: 14px;
  box-shadow: var(--shadow); overflow: hidden; display: none;
}
.search-suggest.show { display: block; }
.search-suggest a {
  display: flex; align-items: center; gap: 10px; padding: 11px 14px;
  font-size: 14px; border-bottom: 1px solid rgba(35, 54, 86, .6); min-height: 46px;
}
.search-suggest a:last-child { border-bottom: 0; }
.search-suggest a:hover { background: rgba(92, 201, 245, .08); }
.search-suggest .sg-emoji { font-size: 17px; }
.search-suggest .sg-tag { margin-left: auto; font-size: 11px; color: var(--txt-3); flex: none; }
.search-suggest .sg-empty { padding: 14px; color: var(--txt-3); font-size: 13.5px; }

/* ---------- 三维运动演示（首页 / 知识点页） ---------- */
.hero3d {
  position: relative; max-width: 1000px; margin: 24px auto 0;
  height: clamp(300px, 46vw, 470px);
  border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden;
  background:
    radial-gradient(120% 92% at 50% 6%, rgba(92, 201, 245, .10), transparent 60%),
    radial-gradient(90% 70% at 22% 96%, rgba(245, 178, 68, .07), transparent 62%),
    linear-gradient(180deg, #0c1526, #0a1120);
  box-shadow: var(--shadow); touch-action: pan-y;
}
.h3d-canvas { display: block; width: 100%; height: 100%; cursor: grab; }
.h3d-canvas:active { cursor: grabbing; }
.h3d-labels { position: absolute; inset: 0; pointer-events: none; }
.h3d-label {
  position: absolute; top: 0; left: 0; display: flex; flex-direction: column; align-items: center;
  gap: 1px; padding: 5px 11px; border-radius: 10px; white-space: nowrap;
  background: rgba(12, 20, 36, .8); border: 1px solid var(--line);
  font-size: 12px; line-height: 1.3; color: var(--txt-2);
  backdrop-filter: blur(6px); will-change: transform;
  transition: opacity .25s, border-color .25s, color .25s;
}
.h3d-label b { font-size: 10.5px; font-weight: 600; letter-spacing: .5px; color: var(--txt-3); }
.h3d-label.on { border-color: var(--green); color: var(--txt); }
.h3d-label.on b { color: var(--green); }
.h3d-cap {
  position: absolute; left: 12px; right: 12px; bottom: 12px;
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  padding: 9px 13px; border-radius: 12px; font-size: 12.5px; color: var(--txt-2);
  background: rgba(12, 20, 36, .84); border: 1px solid var(--line);
  backdrop-filter: blur(8px); pointer-events: none; line-height: 1.45;
}
.h3d-cap b { color: var(--amber); font-weight: 700; }
.h3d-cap .h3d-desc { flex: 1 1 60%; min-width: 0; max-height: 2.9em; overflow: hidden; }
.h3d-cap a { color: var(--green); font-weight: 700; pointer-events: auto; white-space: nowrap; }
.h3d-hint {
  position: absolute; right: 12px; top: 12px; padding: 5px 10px; border-radius: 9px;
  font-size: 11.5px; color: var(--txt-3); background: rgba(10, 17, 32, .7);
  border: 1px solid var(--line); pointer-events: none;
}
.h3d-fallback .h3d-canvas, .h3d-fallback .h3d-labels, .h3d-fallback .h3d-hint { display: none; }
.h3d-fallback::after {
  content: "当前浏览器不支持 WebGL，已跳过三维演示"; position: absolute; inset: 0;
  display: grid; place-items: center; padding: 0 20px; text-align: center;
  color: var(--txt-3); font-size: 13px;
}

/* ---------- 板块大入口 ---------- */
.section-block { padding: 26px 0 8px; }
.section-head { display: flex; align-items: baseline; gap: 12px; margin-bottom: 16px; flex-wrap: wrap; }
.section-head h2 { font-size: 20px; }
.section-head .cnt { color: var(--txt-3); font-size: 13px; }
.section-head .more { margin-left: auto; font-size: 13.5px; color: var(--cyan); }
.portal-grid { display: grid; grid-template-columns: 1fr; gap: 16px; }
.portal {
  position: relative; display: flex; flex-direction: column; border-radius: var(--radius);
  padding: 24px 20px; overflow: hidden;
  background: linear-gradient(155deg, var(--card), var(--card-2));
  border: 1px solid var(--line);
  transition: transform .18s, border-color .18s, box-shadow .18s;
}
.portal:hover { transform: translateY(-3px); border-color: rgba(245, 178, 68, .5); box-shadow: var(--shadow); }
.portal .p-icon { font-size: 34px; line-height: 1; }
.portal h3 { font-size: 19px; margin: 12px 0 6px; }
.portal p { color: var(--txt-2); font-size: 13.5px; }
.portal .p-meta { margin-top: 14px; font-size: 12.5px; color: var(--txt-3); display: flex; gap: 14px; flex-wrap: wrap; }
.portal .p-go {
  margin-top: 12px; text-align: right; font-size: 13px; font-weight: 600;
  color: var(--amber);
}
.portal.is-exam { border-color: rgba(245, 178, 68, .35); }
.portal.is-know { border-color: rgba(92, 201, 245, .30); }
.portal.is-know .p-go { color: var(--cyan); }
.portal .p-glow {
  position: absolute; width: 180px; height: 180px; border-radius: 50%; filter: blur(60px);
  right: -60px; top: -70px; opacity: .5; pointer-events: none;
}
.portal.is-exam .p-glow { background: rgba(245, 178, 68, .25); }
.portal.is-know .p-glow { background: rgba(92, 201, 245, .22); }

/* ---------- 快捷入口 / 动画卡片 ---------- */
.quick-grid, .card-grid { display: grid; grid-template-columns: 1fr; gap: 14px; }
.anim-card {
  display: flex; flex-direction: column; border-radius: 14px;
  background: var(--card); border: 1px solid var(--line);
  padding: 16px; transition: transform .16s, border-color .16s;
}
.anim-card:hover { transform: translateY(-2px); border-color: rgba(92, 201, 245, .45); }
.anim-card .ac-top { display: flex; align-items: center; gap: 10px; }
.anim-card .ac-emoji {
  width: 42px; height: 42px; flex: none; border-radius: 11px; font-size: 22px;
  display: grid; place-items: center; background: var(--card-2); border: 1px solid var(--line);
}
.anim-card .ac-title { font-size: 15.5px; font-weight: 700; line-height: 1.4; }
.anim-card .ac-sub { font-size: 12px; color: var(--txt-3); margin-top: 2px; }
.hot-dot {
  display: inline-block; margin-left: 6px; font-size: 10.5px; font-weight: 700;
  color: #1a1206; background: var(--amber); border-radius: 5px; padding: 1px 6px; vertical-align: 1px;
}
.anim-card .ac-line { color: var(--txt-2); font-size: 13.5px; margin: 10px 0 12px; flex: 1; }
.anim-card .tags { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 12px; }
.tag {
  font-size: 11.5px; color: var(--cyan); background: rgba(92, 201, 245, .10);
  border: 1px solid rgba(92, 201, 245, .25); border-radius: 999px; padding: 2px 9px;
}
.tag.exam { color: var(--amber); background: rgba(245, 178, 68, .10); border-color: rgba(245, 178, 68, .3); }
.anim-card .ac-foot { display: flex; align-items: center; gap: 10px; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  min-height: 40px; padding: 8px 16px; border-radius: 11px; font-size: 14px;
  border: 1px solid var(--line); background: var(--card-2); color: var(--txt);
  transition: filter .15s, background .15s;
}
.btn:hover { filter: brightness(1.12); }
.btn.primary { background: linear-gradient(135deg, var(--amber), #e0881b); border-color: transparent; color: #1a1206; font-weight: 700; }
.btn.cyan { background: linear-gradient(135deg, var(--cyan), #2aa3d6); border-color: transparent; color: #062233; font-weight: 700; }
.btn.ghost { background: transparent; }
.btn.block { width: 100%; }
.btn.sm { min-height: 34px; padding: 5px 12px; font-size: 13px; }

/* ---------- 列表页过滤条 ---------- */
.page-head { padding: 30px 0 6px; }
.page-head h1 { font-size: 24px; }
.page-head p { color: var(--txt-2); font-size: 14px; margin-top: 8px; max-width: 680px; }
.filter-bar { display: flex; gap: 8px; flex-wrap: wrap; margin: 18px 0 6px; }
.chip {
  min-height: 38px; padding: 7px 15px; border-radius: 999px; font-size: 13.5px;
  background: var(--card); border: 1px solid var(--line); color: var(--txt-2);
}
.chip.on { background: rgba(245, 178, 68, .14); border-color: rgba(245, 178, 68, .55); color: var(--amber); font-weight: 600; }
.list-wrap { padding: 14px 0 50px; }
.list-meta { color: var(--txt-3); font-size: 12.5px; margin: 4px 0 16px; }

/* ---------- 知识点树 ---------- */
.kp-layout { display: block; padding: 10px 0 50px; }
.module-tabs { display: flex; gap: 8px; overflow-x: auto; padding: 8px 0 14px; -webkit-overflow-scrolling: touch; scrollbar-width: none; }
.module-tabs::-webkit-scrollbar { display: none; }
.module-tab {
  flex: none; min-height: 44px; padding: 8px 16px; border-radius: 12px;
  background: var(--card); border: 1px solid var(--line); color: var(--txt-2); font-size: 14px;
  display: inline-flex; align-items: center; gap: 7px;
}
.module-tab.on { background: rgba(92, 201, 245, .12); border-color: rgba(92, 201, 245, .55); color: var(--cyan); font-weight: 700; }
.tree { display: flex; flex-direction: column; gap: 12px; }
.tree-module { border: 1px solid var(--line); border-radius: 14px; overflow: hidden; background: var(--card); scroll-margin-top: 76px; }
.tree-module.flash { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(92, 201, 245, .15); }
.tree-module > .m-head {
  width: 100%; display: flex; align-items: center; gap: 10px;
  padding: 14px 16px; background: var(--card-2); border: 0; color: var(--txt);
  font-size: 15.5px; font-weight: 700; text-align: left; min-height: 52px;
}
.tree-module > .m-head .m-caret { margin-left: auto; color: var(--txt-3); transition: transform .2s; font-size: 12px; }
.tree-module.open > .m-head .m-caret { transform: rotate(180deg); }
.m-body { display: none; padding: 6px 10px 12px; }
.tree-module.open .m-body { display: block; }
.topic { border-left: 2px solid var(--line); margin-left: 8px; padding-left: 12px; margin-top: 8px; scroll-margin-top: 76px; border-radius: 6px; }
.topic.flash { border-left-color: var(--cyan); background: rgba(92, 201, 245, .08); box-shadow: 0 0 0 3px rgba(92, 201, 245, .12); }
.t-head {
  width: 100%; display: flex; align-items: center; gap: 8px;
  background: none; border: 0; color: var(--txt); font-size: 14px; font-weight: 600;
  padding: 8px 4px; text-align: left; min-height: 40px;
}
.t-head .t-caret { color: var(--txt-3); transition: transform .2s; font-size: 10px; }
.topic.open .t-caret { transform: rotate(90deg); }
.t-head .t-count { margin-left: auto; font-size: 11px; color: var(--green); font-weight: 500; flex: none; }
.t-points { display: none; padding: 2px 0 8px; }
.topic.open .t-points { display: block; }
.point {
  display: flex; align-items: flex-start; gap: 10px; flex-wrap: wrap;
  padding: 10px 10px; border-radius: 11px; margin: 4px 0;
  background: rgba(22, 36, 63, .45); border: 1px solid transparent;
  scroll-margin-top: 76px;
}
.point.flash { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(92, 201, 245, .15); }
.point .p-name { font-size: 13.5px; line-height: 1.55; flex: 1 1 100%; }
.point .p-id {
  font-family: ui-monospace, Consolas, monospace; font-size: 11px; color: var(--txt-3);
  background: rgba(10, 17, 32, .7); border-radius: 6px; padding: 1px 7px;
}
.point .p-actions { display: flex; gap: 6px; }
.point .p-actions .btn { min-height: 30px; padding: 3px 10px; font-size: 12px; }
.point.has-anim { background: rgba(67, 211, 158, .08); border-color: rgba(67, 211, 158, .25); }
.point .p-anims { flex: 1 1 100%; display: flex; flex-direction: column; gap: 6px; margin-top: 8px; }
.mini-anim {
  display: flex; align-items: center; gap: 9px; padding: 9px 11px;
  background: var(--card-2); border: 1px solid var(--line); border-radius: 10px;
  font-size: 13px; min-height: 42px;
}
.mini-anim:hover { border-color: rgba(67, 211, 158, .5); }
.mini-anim .ma-emoji { font-size: 17px; }
.mini-anim .ma-play { margin-left: auto; color: var(--green); font-size: 12px; font-weight: 700; flex: none; }
.kp-empty-tip { color: var(--txt-3); font-size: 12px; margin-top: 4px; }
.kp-jump {
  display: flex; gap: 8px; align-items: center; margin: 14px 0 4px; flex-wrap: wrap;
  font-size: 12.5px; color: var(--txt-3);
}
.kp-jump select {
  min-height: 38px; border-radius: 10px; background: var(--card); color: var(--txt);
  border: 1px solid var(--line); padding: 0 10px; font-size: 13.5px; max-width: 100%;
}

/* ---------- 搜索结果页 ---------- */
.result-group { margin-bottom: 26px; }
.result-group h3 { font-size: 15px; color: var(--txt-2); margin-bottom: 10px; font-weight: 600; }
.result-item {
  display: flex; gap: 12px; align-items: flex-start; padding: 13px 14px;
  background: var(--card); border: 1px solid var(--line); border-radius: 12px; margin-bottom: 8px;
}
.result-item:hover { border-color: rgba(92, 201, 245, .45); }
.result-item .ri-emoji { font-size: 20px; margin-top: 2px; }
.result-item .ri-title { font-size: 14.5px; font-weight: 700; }
.result-item .ri-sub { font-size: 12.5px; color: var(--txt-3); margin-top: 2px; }
.result-item .ri-badge { margin-left: auto; flex: none; }
.empty-state { text-align: center; padding: 60px 20px; color: var(--txt-3); }
.empty-state .es-emoji { font-size: 42px; display: block; margin-bottom: 12px; }
mark { background: rgba(245, 178, 68, .35); color: var(--amber); border-radius: 3px; padding: 0 2px; }

/* ---------- 动画查看器 ---------- */
.viewer-page { display: flex; flex-direction: column; height: 100vh; height: 100dvh; }
.viewer-bar {
  flex: none; display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  padding: 8px 14px; background: var(--bg-soft); border-bottom: 1px solid var(--line);
}
.viewer-bar .vb-back { flex: none; min-height: 40px; }
.viewer-bar .vb-title { font-size: 14.5px; font-weight: 700; min-width: 0; }
.viewer-bar .vb-crumb { font-size: 12px; color: var(--txt-3); display: block; font-weight: 400; }
.viewer-bar .vb-actions { margin-left: auto; display: flex; gap: 8px; flex: none; }
.stage-wrap {
  position: relative; flex: 1; min-height: 0; background: #05080f;
  display: flex; align-items: center; justify-content: center; overflow: hidden;
}
.stage-wrap iframe.flow { width: 100%; height: 100%; }
/* 未指定动画时选择列表模式：可滚动、顶部对齐 */
.stage-wrap.picker-mode { align-items: flex-start; justify-content: flex-start; overflow-y: auto; }
.picker-list { display: grid; gap: 8px; width: 100%; max-width: 880px; margin: 0 auto; padding: 18px; align-content: start; }
.fixed-box { position: relative; flex: none; }
.fixed-box iframe { transform-origin: top left; background: #04080f; }
.loading-mask {
  position: absolute; inset: 0; z-index: 10; display: grid; place-items: center;
  background: #05080f; transition: opacity .35s; pointer-events: none;
}
.loading-mask.hide { opacity: 0; }
.loading-inner { text-align: center; color: var(--txt-2); font-size: 14px; }
.spinner {
  width: 42px; height: 42px; margin: 0 auto 14px; border-radius: 50%;
  border: 3px solid var(--line); border-top-color: var(--amber);
  animation: spin 1s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.loading-mask .retry-btn { margin-top: 14px; }
.info-panel {
  position: absolute; left: 0; right: 0; bottom: 0; z-index: 15;
  max-height: 52vh; overflow-y: auto;
  border-top: 1px solid var(--line);
  background: rgba(13, 22, 40, .94);
  -webkit-backdrop-filter: blur(10px); backdrop-filter: blur(10px);
  padding: 14px 16px calc(14px + env(safe-area-inset-bottom, 0px));
  display: none;
  box-shadow: 0 -8px 30px rgba(0, 0, 0, .45);
}
.info-panel.show { display: block; }
.info-panel .ip-grid { display: grid; gap: 12px; max-width: 1200px; margin: 0 auto; }
.info-panel h4 { font-size: 13px; color: var(--cyan); margin-bottom: 6px; }
.info-panel .ip-line { font-size: 13.5px; }
.info-panel ol { padding-left: 20px; font-size: 13px; color: var(--txt-2); }
.info-panel ol li { margin: 3px 0; }
.info-panel .ip-concl {
  font-size: 13.5px; background: rgba(67, 211, 158, .08); border: 1px solid rgba(67, 211, 158, .3);
  border-radius: 11px; padding: 10px 13px;
}
.info-panel .ip-related { display: flex; gap: 8px; flex-wrap: wrap; }
.ip-toggle {
  position: absolute; right: 12px; bottom: 12px; z-index: 20;
  min-height: 40px; padding: 8px 14px; border-radius: 999px;
  background: rgba(18, 29, 51, .92); border: 1px solid var(--line); color: var(--txt);
  font-size: 13px; backdrop-filter: blur(8px);
}

/* ---------- 页脚 ---------- */
.footer { border-top: 1px solid var(--line); padding: 26px 0 34px; color: var(--txt-3); font-size: 12.5px; text-align: center; }
.footer a { color: var(--cyan); }

/* ---------- Toast ---------- */
.toast {
  position: fixed; left: 50%; bottom: 28px; transform: translateX(-50%) translateY(20px);
  background: rgba(18, 29, 51, .96); border: 1px solid var(--cyan);
  color: var(--txt); padding: 11px 20px; border-radius: 999px; font-size: 13.5px;
  opacity: 0; pointer-events: none; transition: opacity .25s, transform .25s; z-index: 100;
  max-width: 90vw; text-align: center; box-shadow: var(--shadow);
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ============================================================
 * 断点 1：平板 ≥768px
 * ============================================================ */
@media (min-width: 768px) {
  .hero h1 { font-size: 34px; }
  .portal-grid { grid-template-columns: 1fr 1fr; }
  .quick-grid, .card-grid { grid-template-columns: 1fr 1fr; }
  .page-head h1 { font-size: 28px; }
  .info-panel .ip-grid { grid-template-columns: 1fr 1fr; }
  .info-panel .ip-grid .ip-span2 { grid-column: 1 / -1; }
}

/* ============================================================
 * 小屏（手机）：三维演示收紧文字与提示
 * ============================================================ */
@media (max-width: 767px) {
  .hero3d { margin-top: 20px; }
  .h3d-hint { display: none; }
  .h3d-label { font-size: 11px; padding: 4px 9px; }
  .h3d-label b { font-size: 10px; }
  .h3d-cap { left: 9px; right: 9px; bottom: 9px; font-size: 12px; padding: 8px 11px; }
}

/* ============================================================
 * 断点 2：宽屏 PC ≥1200px
 * ============================================================ */
@media (min-width: 1200px) {
  .hero { padding: 58px 0 36px; }
  .hero h1 { font-size: 40px; }
  .hero3d { height: 500px; margin-top: 30px; }
  .quick-grid, .card-grid { grid-template-columns: repeat(3, 1fr); }
  .kp-layout { display: grid; grid-template-columns: 232px minmax(0, 1fr); gap: 26px; align-items: start; }
  .module-tabs {
    position: sticky; top: 72px; flex-direction: column; overflow: visible;
    padding: 0; gap: 8px;
  }
  .module-tab { width: 100%; }
  .tree-module > .m-head { cursor: pointer; }
  .info-panel { max-height: 42vh; }
  .info-panel .ip-grid { grid-template-columns: repeat(4, 1fr); }
  .info-panel .ip-grid .ip-span2 { grid-column: span 2; }
  .ip-toggle { display: none; }
  .info-panel { display: block; }
}

/* ============================================================
 * 超小屏 320px 专项保护（默认即移动优先，此处收紧尺寸）
 * ============================================================ */
@media (max-width: 360px) {
  .container { padding: 0 12px; }
  .topnav .inner { padding: 0 12px; gap: 6px; }
  .brand { font-size: 13px; gap: 7px; }
  .brand .logo { width: 28px; height: 28px; font-size: 15px; }
  .brand small { display: none; }
  .nav-links { gap: 2px; }
  .nav-links a { padding: 7px 8px; font-size: 12.5px; }
  .hero h1 { font-size: 23px; }
  .hero p.sub { font-size: 13.5px; }
  .hero3d { height: 272px; }
  .h3d-label { font-size: 10px; padding: 3px 7px; }
  .h3d-cap { font-size: 11.5px; padding: 7px 10px; gap: 7px; }
  .searchbox input { padding-left: 42px; padding-right: 78px; font-size: 14px; }
  .portal { padding: 20px 16px; }
  .anim-card { padding: 14px; }
  .viewer-bar { padding: 7px 10px; gap: 7px; }
  .viewer-bar .vb-title { font-size: 13.5px; }
  .viewer-bar .vb-actions .btn { padding: 7px 10px; font-size: 12.5px; }
}

/* ============================================================
 * 竖屏（手机竖持 / 平板竖持）：16:9 固定舞台顶对齐，
 * 黑边集中到下方浮层区，避免舞台悬在视口中部
 * ============================================================ */
@media (max-width: 1199px) and (orientation: portrait) {
  .stage-wrap { align-items: flex-start; }
  .fixed-box { margin-top: 8px; }
}