:root{font-family:"Microsoft YaHei","PingFang SC",system-ui,sans-serif;color:#22372f;font-synthesis:none;font-size:16px;--green:#254b3d;--line:rgba(35,57,46,.12);--glass:rgba(255,254,248,.92)}*{box-sizing:border-box}body{margin:0;overflow:hidden;background:#dddace}button,a{-webkit-tap-highlight-color:transparent}button{font:inherit;cursor:pointer;color:inherit;border:0}button:focus-visible,a:focus-visible{outline:3px solid 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#172c2824;backdrop-filter:blur(18px);overflow:hidden;display:flex;flex-direction:column;z-index:8;transition:transform .3s,opacity .3s}.lesson-panel.collapsed{transform:translateX(calc(100% + 40px));opacity:0;pointer-events:none}.panel-top{display:flex;align-items:center;justify-content:space-between;padding:17px 21px 5px}.eyebrow{font-size:13px;letter-spacing:1px;color:#697a6d}.icon-btn.small{width:30px;height:30px;background:transparent;border:0;box-shadow:none}.scene-tabs{display:flex;margin:8px 21px 4px;background:#e5e9e14f;padding:4px;border-radius:12px;border:1px solid var(--line)}.scene-tabs button{width:50%;font-size:15px;background:transparent;border-radius:9px;padding:10px}.scene-tabs button.active{background:var(--green);color:white;box-shadow:0 3px 9px #1d443421}.panel-scroll{overflow:auto;padding:0 23px 23px;scrollbar-width:thin;scrollbar-color:#b7c5b9 transparent}.scene-heading{display:flex;align-items:center;gap:8px;margin:22px 0 15px}.scene-symbol{color:#c48437;font-size:23px}.scene-heading h2{font-size:20px;line-height:1.6;margin:0;font-weight:650;letter-spacing:.1px}.story-text{position:relative;background:#fff9;padding:19px 18px 14px;border-radius:13px;border:1px solid #d8ddcc}.quote-mark{font-family:Georgia,serif;font-size:46px;line-height:28px;color:#abb99c;display:block;height:22px}.story-text p{font-size:16px;line-height:1.9;margin:5px 0 10px;color:#405246}.speaker{display:block;text-align:right;font-size:13px;color:#80917f}.intention{font-size:15px;line-height:1.8;margin:18px 0 20px;color:#627158}.panel-buttons{display:grid;gap:10px;grid-template-columns:1fr}.primary-btn{background:var(--green);color:white;border-radius:11px;padding:13px 17px;font-size:15px;min-height:46px;transition:background .2s}.primary-btn:hover{background:#163c2c}.secondary-btn{display:flex;align-items:center;justify-content:center;gap:8px;background:transparent;border:1px solid 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svg{width:19px;height:19px}.nav-hint{display:block;font-size:12px;text-align:center;margin-top:9px;color:#6e7a6b;white-space:nowrap}.bottom-left{position:fixed;left:30px;bottom:25px;display:flex;flex-direction:column;gap:11px;align-items:flex-start;pointer-events:none}.minimap-wrap{width:110px;padding:6px;background:rgba(253,254,248,.83);border:1px solid #fff9;border-radius:13px;box-shadow:0 3px 20px #24332913}.minimap-wrap canvas{display:block;width:96px;height:103px}.minimap-wrap span{display:block;text-align:center;color:#7b876f;font-size:10px;letter-spacing:1px;margin:2px 0 4px}.reset-btn{pointer-events:auto;display:flex;align-items:center;gap:7px;color:#fdfcf2;font-size:12px;background:#1a2d27b3;border:1px solid #fff2;border-radius:10px;padding:9px 12px;backdrop-filter:blur(8px)}.reset-btn svg{width:15px;height:15px}.move-pad{position:fixed;right:34px;bottom:25px;display:grid;grid-template-columns:repeat(3,42px);grid-template-rows:repeat(2,40px);gap:5px;z-index:7}.move-pad button{border-radius:10px;background:#f9fbf0d6;border:1px solid #fff9;color:#465d46;font-size:14px;box-shadow:0 3px 14px #29382114;touch-action:none;user-select:none}.move-pad button:active,.move-pad button.held{background:#31553d;color:white}.move-forward{grid-column:2}.move-left{grid-column:1;grid-row:2}.move-back{grid-column:2;grid-row:2}.move-right{grid-column:3;grid-row:2}.hotspot{position:fixed;top:0;left:0;display:flex;align-items:center;gap:9px;padding:0;background:transparent;will-change:transform;z-index:4;transition:opacity .2s;white-space:nowrap}.hotspot-dot{width:35px;height:35px;border:2px solid #fff;box-shadow:0 0 0 6px #fff3,0 3px 14px #282b183d;border-radius:50%;display:grid;place-items:center;background:#bf863d;color:white;font-weight:650;font-size:15px}.hotspot-label{font-size:13px;color:#fff;background:#203a32c9;border:1px solid #ffffff30;padding:9px 12px;border-radius:9px;backdrop-filter:blur(10px)}.hotspot:hover 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h1{font-size:23px;letter-spacing:2px;margin:27px 0 8px;font-weight:500}.loader p{font-size:14px;color:#72816a}.load-track{margin-top:15px;height:3px;width:200px;background:#d9dfd0;overflow:hidden}.load-track i{display:block;height:100%;width:0;background:#b28b4c;transition:width .3s}dialog{border:1px solid #d1d7c8;border-radius:23px;padding:28px;color:#304934;background:#fdfdf6;max-width:480px;width:calc(100% - 36px);box-shadow:0 25px 100px #15271e60}dialog::backdrop{background:#1d322b66;backdrop-filter:blur(5px)}.dialog-heading{display:flex;align-items:center;justify-content:space-between;gap:20px}.dialog-heading h2{font-size:22px;margin:0}.dialog-heading .icon-btn{font-size:25px;box-shadow:none}dialog p{font-size:15px;line-height:1.8}dialog dl{display:grid;grid-template-columns:95px 1fr;gap:15px 12px;font-size:14px;line-height:1.7;margin:25px 0}dialog dt{font-weight:650}dialog dd{margin:0;color:#69775f}dialog .primary-btn{width:100%}video{width:100%;margin-top:16px;background:#16281d;border-radius:11px;aspect-ratio:16/9}.walking .lesson-panel,.walking .location,.walking .hotspot{opacity:0;pointer-events:none}.walking .nav-hint{color:#8f5726}.walking .walking .topbar{opacity:.5}body.focus-scene .hotspot{opacity:0;pointer-events:none}@media(max-width:1100px){.lesson-panel{width:310px;right:20px}.scene-heading h2{font-size:18px}.panel-scroll{padding:0 18px 18px}.topbar{left:20px;right:20px}.hotspot-label{display:none}.navigation-bar{left:44%}}@media(max-height:730px) and (min-width:761px){.lesson-panel{max-height:calc(100dvh - 195px)}.panel-scroll .story-text p{font-size:14px;line-height:1.75}.intention{font-size:14px;margin:12px 0}.scene-heading{margin:14px 0 10px}.panel-top{padding-top:10px}.brand{padding:8px 15px 8px 9px}.topbar{top:16px}.lesson-panel{top:91px}.minimap-wrap{display:none}.navigation-bar{bottom:17px}.bottom-left,.move-pad{bottom:19px}}@media(max-width:760px){.topbar{top:14px;left:13px;right:13px}.brand{padding:9px 13px 9px 9px;gap:9px;border-radius:13px}.brand-icon{width:35px;height:35px;border-radius:9px}.brand-icon svg{width:22px;height:22px}.brand strong{font-size:16px}.brand small{font-size:10px;letter-spacing:1px}.top-actions{gap:6px}.top-actions .soft-btn{display:none}.icon-btn{width:36px;height:36px;border-radius:10px}.location{top:92px;left:19px}.location span:nth-child(2){font-size:12px}.location small{font-size:10px}.sun-icon{font-size:22px}.lesson-panel{right:13px;top:88px;width:min(310px,calc(100vw - 26px));max-height:calc(100dvh - 225px);border-radius:17px}.lesson-panel:not(.collapsed)~.move-pad{opacity:.9}.panel-top{padding-top:11px}.eyebrow{font-size:12px}.scene-tabs button{font-size:14px;padding:8px}.scene-heading{margin:15px 0 10px}.story-text{padding:14px}.story-text p{font-size:15px;line-height:1.75}.intention{font-size:14px;margin:12px 0}.secondary-btn,.primary-btn{font-size:14px;min-height:41px;padding:10px}.navigation-bar{bottom:17px;left:13px;transform:none;padding:5px 5px 9px;border-radius:13px}.mode-buttons button{font-size:12px;padding:9px;gap:5px}.mode-buttons svg{width:16px;height:16px}.nav-hint{font-size:10px;margin-top:6px}.bottom-left{left:14px;bottom:115px}.minimap-wrap{display:none}.reset-btn{font-size:11px;padding:7px 9px}.move-pad{right:15px;bottom:17px;grid-template-columns:repeat(3,37px);grid-template-rows:repeat(2,38px);gap:4px}.expand-btn{right:13px;top:89px;font-size:13px;padding:12px}.toast{bottom:118px;font-size:13px;width:max-content}.hotspot-dot{width:29px;height:29px;font-size:13px}.hotspot-label{display:none}.choice span span{font-size:14px}.choice{padding:12px 10px}.choice strong{font-size:13px}}@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
.video-entry{display:flex;align-items:center;gap:12px;width:100%;text-align:left;background:#ece8d4a8;border:1px solid #d9d4b9;border-radius:12px;padding:14px;margin-top:16px}.video-entry>svg{width:38px;height:38px;background:#a87c3b;color:#fff;border-radius:50%;padding:9px;fill:#fff;stroke:none}.video-entry span{font-size:15px;font-weight:550}.video-entry small{display:block;font-size:12px;font-weight:400;color:#858571;margin-top:5px}.video-entry:hover{background:#e8e0c2}#videoDialog{max-width:1040px;width:calc(100vw - 40px);padding:20px;background:#f8f9f1}#videoDialog video{max-height:calc(100dvh - 190px);display:block;margin-top:18px;border-radius:13px;background:#16241b}.video-footer{display:flex;align-items:center;justify-content:space-between;margin-top:14px;gap:15px}.video-footer span{font-size:14px;color:#7b856e}.video-footer .primary-btn{width:auto;padding:10px 30px}@media(max-width:760px){#videoDialog{width:calc(100vw - 20px);padding:13px;border-radius:15px}#videoDialog h2{font-size:17px}.video-footer span{font-size:12px}.video-footer .primary-btn{font-size:13px;padding:10px 16px}}

/* 静态教室背景：无模型、材质、HDR或持续渲染。 */
#world{pointer-events:none}#classroomBackground{display:block;width:100%;height:100%;object-fit:cover;object-position:center}