:root{--ink:#163c3c;--muted:#54716e;--paper:#f5f1e7;--gold:#b17d37;--line:#d5ded5;--teal:#16685e;font-family:'Microsoft YaHei','PingFang SC',sans-serif;color:var(--ink);background:var(--paper)}*{box-sizing:border-box}body{margin:0}button,select,input,textarea{font:inherit}button,select{cursor:pointer}button{padding:12px 19px;border:1px solid #93b0a5;border-radius:9px;background:#fffdf7;color:var(--ink);font-size:clamp(16px,1.3vw,21px);font-weight:600}button:hover{background:#e2ede4}button:focus-visible,select:focus-visible,input:focus-visible,textarea:focus-visible{outline:3px solid 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15px;background:#173d3de8;color:#f8e3ac;border-color:#bd9961;font-size:16px;z-index:4}dialog{width:min(96vw,1450px);height:min(95dvh,1100px);border:0;border-radius:12px;padding:20px;background:#f8f5ed;color:var(--ink);text-align:center}dialog::backdrop{background:#062320df}dialog img{max-width:100%;max-height:calc(100% - 94px);object-fit:contain;margin:0 auto}dialog p{font-size:14px;line-height:1.5;margin:10px 0}#closeImage{display:block;margin:0 0 10px auto;font-size:16px;padding:6px 14px}#toast{position:fixed;left:50%;bottom:90px;transform:translateX(-50%);padding:13px 22px;max-width:90vw;border-radius:9px;background:#143d3cf0;color:white;z-index:100;opacity:0;pointer-events:none;transition:opacity .2s;font-size:18px}#toast.visible{opacity:1}[hidden]{display:none!important}@media(max-height:760px) and (min-width:1000px){.slide{padding-top:22px;padding-bottom:22px}h2{font-size:38px;margin-bottom:22px}p{font-size:21px;line-height:1.6;margin-bottom:17px}.lead{font-size:29px}h3{font-size:28px}.large-note{padding:24px 28px}.bottom-call{margin-top:22px}.hero h1{font-size:74px}.hero .lead{font-size:29px}.note{font-size:19px;margin:15px 0}.transfer-grid textarea{min-height:85px}.chips{margin-bottom:20px}.number{font-size:30px;margin-bottom:10px}article{padding:24px}details p{font-size:17px}}@media(max-width:900px){.slide{padding:25px;justify-content:flex-start!important}.split,.hero,.three,.transfer-grid{grid-template-columns:1fr!important}.hero-photo{height:45vh}.hero h1 br{display:none}.hero h1{font-size:58px}.hero{gap:25px}.photo-split{gap:24px}.lead{font-size:27px}.cards{gap:14px}.cards article{padding:19px}.number{float:left;font-size:25px;margin-right:20px}#toolbar{height:auto;min-height:70px;gap:5px;padding:9px;flex-wrap:wrap}#toolbar button,#toolbar select{font-size:14px;padding:7px}#pageSelect{max-width:140px}.grade-label{display:none}.spacer{display:none}#classroom{height:calc(100dvh - 112px)}.handbook-card{max-height:480px}.handbook-card img{max-height:480px}.bottom-call{margin-top:20px}.photo-split img{max-height:50vh}.hero-copy>p{font-size:19px}}@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}

body.bar-hidden #demoPanel{bottom:0}@media(max-width:900px){#demoPanel{bottom:112px}}
/* 三江口课堂增补：静态公共图标与大屏构图 */
.slide-head{display:flex;gap:20px;align-items:center;margin-bottom:28px}.slide-head h2{margin:0;flex:1}.activity-icon{width:100px;height:100px;object-fit:contain;background:transparent;border-radius:22px;flex:none}.two{grid-template-columns:1fr 1fr}.rule-tag{font-size:33px;display:inline-block;background:#ad742e;color:white;padding:8px 22px;border-radius:12px;margin-bottom:12px}.rule-tag.teal{background:#16685e}.command{font-size:clamp(40px,4.4vw,72px);background:#fffcf5;border:2px solid #b79b67;padding:24px 30px;border-radius:16px;margin-bottom:24px;letter-spacing:.08em}.button{display:inline-block;text-decoration:none;padding:12px 18px;border:1px solid #93b0a5;border-radius:9px;background:#fffdf7;font-size:19px}.footer-line{margin-top:26px;margin-bottom:0;color:#54716e}.hero-photo figcaption{position:absolute;bottom:0;left:0;right:0;margin:0;padding:60px 28px 25px;background:linear-gradient(transparent,#092928e8);color:white;font-size:25px;line-height:1.7}.hero-photo figcaption span{font-size:18px;color:#ecdfb8}.demo-top{height:54px;display:flex;align-items:center;gap:24px;padding:6px 18px;color:#f3eddc;background:#133b3b}.demo-top span{font-size:16px;flex:1}.demo-top #closeDemo{position:static;font-size:16px;padding:7px 15px}#demoPanel iframe{height:calc(100% - 54px)}.compare-shots{display:grid;grid-template-columns:1fr 1fr;gap:20px}.compare-shots figure{padding:12px;background:#fffaf0;border:1px solid #cedbd1;border-radius:14px}.compare-shots figcaption{font-size:22px;color:#163c3c}.compare-shots img{width:100%;display:block;border-radius:8px}.handbook-card img{object-fit:contain}body.reduced *{animation:none!important;transition:none!important}.rest .slide-head{justify-content:center}.rest .slide-head h2{flex:none}#classroom:focus{outline:none}
@media(max-height:760px) and (min-width:1000px){.activity-icon{width:76px;height:76px}.slide-head{margin-bottom:22px}.slide-head h2{font-size:36px}.cards.two article{padding:20px 26px}.cards.two p{font-size:21px;line-height:1.5}.rule-tag{font-size:27px;padding:5px 19px}.command{font-size:50px}.compare-shots figcaption{font-size:18px}.footer-line{margin-top:19px}.hero-photo figcaption{font-size:23px}}
@media(max-width:900px){.two,.compare-shots{grid-template-columns:1fr}.activity-icon{width:65px;height:65px}.slide-head{gap:12px}.slide-head h2{font-size:30px}.demo-top span{display:none}.demo-top{gap:10px}.demo-top strong{flex:1}.command{font-size:35px}}
@media(max-height:760px) and (min-width:1000px){.photo-split .image-button img{max-height:calc(100dvh - 260px);width:100%;object-fit:contain}.photo-split .image-button{width:100%}}
.slide.route-review .bottom-call{flex-wrap:nowrap}.slide.route-review .bottom-call p{flex:1;flex-basis:auto;margin:0}.slide.route-review .bottom-call button{flex:none}@media(max-width:900px){.slide.route-review .bottom-call{flex-wrap:wrap}.slide.route-review .bottom-call p{flex-basis:100%}}
.slide.rule-overview article .small{font-size:22px;line-height:1.6}@media(max-height:760px) and (min-width:1000px){.slide.rule-overview article .small{font-size:20px}}

/* 第02课开场：沿用原02—13课PPT满幅纸雕图与左侧标题构图。 */
.slide.hero{position:relative;isolation:isolate;max-width:none;overflow:hidden;padding:42px 5vw;background:#103e40;color:#fff9eb;gap:0}
.slide.hero.active{display:flex;align-items:flex-start;justify-content:center}
.hero .opening-art{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:-2}
.hero::before{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,rgba(16,62,64,.95) 0%,rgba(16,62,64,.78) 35%,rgba(16,62,64,.05) 100%)}
.hero-copy{width:min(620px,48vw);position:relative}
.hero .series{font-size:clamp(20px,2vw,32px);letter-spacing:.035em;color:#e4c78c;margin-bottom:clamp(30px,6vh,70px)}
.hero h1{font-size:clamp(52px,5.25vw,84px);line-height:1.2;letter-spacing:.015em;white-space:nowrap;margin:0 0 28px;color:#fff9eb}
.hero .lead{font-size:clamp(28px,2.875vw,46px);line-height:1.5;margin-bottom:24px;color:#fff9eb}
.hero-copy>p:not(.series):not(.lead){font-size:clamp(18px,1.4vw,23px);line-height:1.6;color:#eee5d0;margin-bottom:26px}
.hero .primary{background:#e4c78c;border-color:#e4c78c;color:#123d3e;padding:13px 23px}
.hero .primary:hover{background:#f3dcae}
.hero .opening-note{position:absolute;bottom:18px;right:28px;margin:0;font-size:14px;letter-spacing:.04em;color:#f6edda;text-shadow:0 1px 5px #092d32}
@media(max-height:760px) and (min-width:901px){.slide.hero{padding-top:28px;padding-bottom:42px}.hero .series{margin-bottom:32px}.hero h1{margin-bottom:24px}.hero .lead{margin-bottom:18px}.hero-copy>p:not(.series):not(.lead){margin-bottom:20px}}
@media(max-width:900px){.slide.hero.active{justify-content:center!important}.slide.hero{padding:40px 6vw 64px}.hero-copy{width:88vw}.hero .opening-art{object-position:62% center}.hero::before{background:linear-gradient(90deg,#103e40ee,#103e40b8 60%,#103e4040)}.hero .series{font-size:22px;margin-bottom:38px}.hero h1{font-size:clamp(38px,7vw,60px)}.hero .lead{font-size:30px}.hero .opening-note{left:6vw;right:auto;font-size:12px}}
body.bar-hidden .hero .opening-note{bottom:70px}


/* R2026-09-08.3：七页历史介绍与三页故事。 */
.history .slide-head{margin-bottom:25px}.history .activity-icon{width:76px;height:76px;border-radius:18px}.history .slide-head h2{font-size:clamp(34px,3.2vw,52px)}
.history .lead{font-size:clamp(26px,2.5vw,40px);line-height:1.55}.history-split{grid-template-columns:1.1fr 1fr;gap:50px}
.epoch{display:inline-block;color:#9c6e2f;font-size:clamp(26px,2.5vw,40px);font-weight:600;letter-spacing:.04em;margin-bottom:20px}
.history .history-source{font-size:13px;line-height:1.5;margin:18px 0 0;color:#60776b}.history-source a{text-underline-offset:3px}
.history .history-question{font-size:clamp(23px,1.9vw,30px);line-height:1.5;color:#19675b;margin:20px 0 0}
.river-diagram{background:#e6eee4;border:1px solid #c5d3c6;border-radius:15px;padding:12px 18px}.river-diagram svg{display:block;width:100%;max-height:215px}.river-diagram span{font-size:13px;color:#60776b}
.old-map{display:flex;flex-direction:column;align-items:center}.old-map .image-button{display:flex;justify-content:center;width:100%}.old-map img{height:min(57vh,600px);max-width:100%;object-fit:contain;border-radius:8px}.old-map figcaption{font-size:15px;text-align:center}
.harbor-flow{background:#e6eee4;border:1px solid #c3d1c6;border-radius:18px;padding:25px 35px;text-align:center}.harbor-flow>div{padding:16px;border:1px solid #bfd0c1;background:#fffaf0;border-radius:12px}.harbor-flow span{display:block;font-size:18px;color:#6d7c64;margin-bottom:7px}.harbor-flow b{font-size:clamp(23px,2vw,32px);color:#1c5148}.harbor-flow i{display:block;font-size:26px;line-height:1.3;color:#ae7c35;font-style:normal}.harbor-flow .small{margin:15px 0 0}
.old-photo-page .photo-split{grid-template-columns:1.5fr .85fr}.old-photo-page .image-button img{width:100%;height:auto;max-height:55vh;object-fit:contain}.old-photo-page figcaption{font-size:15px}
.history-pair{display:grid;grid-template-columns:1fr 1fr;gap:25px}.history-pair figure{padding:20px;background:#fffaf0;border:1px solid #c5d1c4;border-radius:14px}.history-pair .period-label{font-size:clamp(22px,2vw,31px);font-weight:600;line-height:1.4;margin-bottom:14px}.history-pair .image-button{width:100%}.history-pair img{height:32vh;max-height:340px;min-height:200px;width:100%;object-fit:contain;background:#e7e5d8}.history-pair figcaption{font-size:14px}
.comparison-limit{font-size:16px;color:#60776b;margin:13px 0 0;line-height:1.6}
.history-timeline{display:grid;grid-template-columns:repeat(3,1fr);gap:22px}.history-timeline article{padding:24px 27px}.history-timeline span{display:block;color:#a06f2c;font-size:25px;margin-bottom:16px}.history-timeline h3{font-size:27px}.history-timeline p{font-size:24px;margin:0;line-height:1.5}
.history-bridge{display:grid;grid-template-columns:1fr 1fr auto;gap:25px;align-items:center;margin-top:32px}.history-bridge p{font-size:24px;margin:0;line-height:1.6}.history-bridge .lead{font-size:31px}.history-bridge button{white-space:nowrap}
.slide.story-spread.active{display:grid;grid-template-columns:1fr 1fr;gap:clamp(35px,4vw,70px);align-items:center;justify-content:center}
.story-art-large{width:min(100%,65vh);aspect-ratio:1;background-image:url('../资源/三江口任务故事.png');background-size:300% 100%;background-position:var(--position) center;background-repeat:no-repeat;border-radius:24px;margin:auto;box-shadow:0 15px 45px #173a3525}
.story-prose .chapter-label{font-size:20px;color:#a06f2c;letter-spacing:.05em;margin-bottom:20px}
.story-prose h2{font-size:clamp(37px,3.7vw,59px);margin-bottom:24px;line-height:1.35}
.story-prose>p:not(.chapter-label):not(.story-source){font-size:clamp(22px,1.8vw,29px);line-height:1.7;margin-bottom:20px}
.story-prose blockquote{font-size:clamp(23px,2vw,32px);line-height:1.6;background:#e4eadc;border-left:4px solid #a67d3b;padding:18px 22px;margin:20px 0}
.story-prose .story-ask{color:#19675b;font-weight:600}.story-prose .story-source{font-size:13px;line-height:1.5;color:#60776b;margin:14px 0 0}
@media(max-height:760px) and (min-width:901px){
.history .slide-head{margin-bottom:18px}.history .activity-icon{width:57px;height:57px}.history .slide-head h2{font-size:34px}.history .lead{font-size:28px;margin-bottom:17px}.history-split{gap:35px}.epoch{font-size:27px;margin-bottom:15px}
.history .history-source{margin-top:12px;font-size:12px}.history .history-question{font-size:23px;margin-top:15px}.river-diagram svg{max-height:165px}.river-diagram span{font-size:12px}.old-map img{height:50vh}.old-map figcaption{font-size:13px}.harbor-flow{padding:18px 25px}.harbor-flow>div{padding:12px}.harbor-flow span{font-size:16px}.harbor-flow b{font-size:24px}
.history-pair{gap:18px}.history-pair figure{padding:15px}.history-pair .period-label{font-size:23px}.history-pair img{height:28vh;min-height:160px}.history-pair figcaption{font-size:13px}.comparison-limit{font-size:14px}
.history-timeline article{padding:20px}.history-timeline h3{font-size:23px}.history-timeline span{font-size:23px}.history-timeline p{font-size:22px}.history-bridge{gap:20px;margin-top:24px}.history-bridge .lead{font-size:27px}.history-bridge p{font-size:21px}
.story-art-large{width:min(100%,65vh)}.story-prose .chapter-label{font-size:17px;margin-bottom:12px}.story-prose h2{font-size:37px;margin-bottom:17px}.story-prose>p:not(.chapter-label):not(.story-source){font-size:20px;line-height:1.5;margin-bottom:14px}.story-prose blockquote{font-size:23px;line-height:1.5;padding:14px 18px;margin:15px 0}.story-prose .story-source{font-size:12px;margin-top:11px}
}
@media(max-width:900px){.history-split,.history-pair,.history-timeline,.history-bridge{grid-template-columns:1fr}.history .slide-head h2{font-size:30px}.history .activity-icon{width:60px;height:60px}.old-map img{height:480px;max-height:60vh}.history-pair img{height:30vh}.history-bridge button{justify-self:start}.slide.story-spread.active{grid-template-columns:1fr}.story-art-large{width:min(80vw,480px)}.story-prose h2{font-size:38px}.story-prose .chapter-label{margin-top:10px}.story-prose>p:not(.chapter-label):not(.story-source){font-size:23px}.story-prose blockquote{font-size:25px}.history-source{overflow-wrap:anywhere}}

.demo-top strong{color:#f3eddc}
/* R2026-09-08.7: shared history materials with grade-specific questions. */
.slide.history40{padding:28px 4vw;justify-content:center;max-width:1700px}
.history40 .slide-head{margin-bottom:20px;gap:18px}.history40 .activity-icon{width:64px;height:64px}.history40 h2{font-size:clamp(30px,3.1vw,48px);line-height:1.3}
.h40-grid{display:grid;grid-template-columns:1.08fr 1fr;gap:36px;align-items:center;min-height:0}.history40 .lead{font-size:clamp(25px,2.45vw,36px);line-height:1.55;margin-bottom:20px}.h40-grid p{font-size:clamp(21px,1.75vw,28px);line-height:1.5;margin-bottom:18px}.history40 .epoch{font-size:25px;margin-bottom:16px}
.h40-media{min-width:0;margin:0}.h40-media .image-button{display:flex;width:100%;align-items:center;justify-content:center}.h40-media img{height:35vh;max-height:360px;min-height:190px;width:100%;object-fit:contain;border-radius:12px}.h40-media figcaption{font-size:13px;line-height:1.5;color:#62766b;margin-top:8px}.h40-small{font-size:19px!important;color:#5a7268}.h40-source{font-size:12px!important;line-height:1.45;margin:10px 0 0!important;color:#60746b}.h40-source a{color:inherit}
.inquiry{background:#e4ebdf;border-left:5px solid #3b8274;border-radius:0 13px 13px 0;padding:16px 22px;margin-top:22px}.inquiry .ask{font-size:clamp(24px,2vw,31px);font-weight:600;line-height:1.4;color:#174f45;margin:0 0 8px}.inquiry .support{font-size:clamp(18px,1.35vw,23px);line-height:1.45;margin:0;color:#4b6357}
.h40-diagram svg{width:100%;height:36vh;max-height:370px;display:block}.h40-diagram p{font-size:14px;text-align:center;color:#61796c;margin:8px 0}.h40-location{display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:16px;padding:25px;border:1px solid #bacbbf;border-radius:18px;background:#e3ece2}.h40-location div{background:#fffaf0;border-radius:14px;padding:30px 18px;text-align:center}.h40-location b{display:block;font-size:34px;margin-bottom:14px}.h40-location span{font-size:19px;line-height:1.6}.h40-location>p{font-size:19px}.h40-location small{grid-column:1/-1;font-size:15px;text-align:center;line-height:1.7}.fact-quote{font-size:27px;color:#9d6b24;border-left:4px solid #bc914f;padding:16px 20px;background:#fffbef;margin:18px 0}
.h40-route{display:grid;grid-template-columns:1fr auto 1fr;gap:15px;padding:25px;background:#e3ece2;border-radius:18px;text-align:center;align-items:center}.h40-route>div{padding:20px 10px;border-radius:12px;background:#fffaf0}.h40-route span{display:block;font-size:19px;color:#596e60;margin-bottom:13px}.h40-route b{font-size:31px}.h40-route p{font-size:19px;margin:13px 0 0}.h40-route i{font-size:18px;font-style:normal}.h40-route aside{grid-column:1/-1;border-top:1px solid #bdcebf;padding:20px 0 0}.h40-route aside b{font-size:26px}.h40-route small{grid-column:1/-1;font-size:14px;line-height:1.7}
.h40-artifacts,.h40-pair{display:grid;grid-template-columns:1fr 1fr;gap:28px}.h40-artifacts figure{background:#fffcf5;border:1px solid #c9d4c9;border-radius:16px;padding:16px}.h40-artifacts img{height:31vh;max-height:340px}.h40-pair img{height:30vh;max-height:320px}.h40-pair figcaption{font-size:16px}.h40-limit{font-size:15px;margin:8px 0 0;color:#596f63}
.h40-evidence{display:grid;gap:12px}.h40-evidence article{display:grid;grid-template-columns:130px 1fr;gap:6px 15px;padding:14px 18px;background:#fffaf0;border:1px solid #c6d3c7;border-radius:12px}.h40-evidence span{font-size:18px;color:#947031;align-self:center}.h40-evidence b{font-size:27px}.h40-evidence p{grid-column:1/-1;font-size:20px;margin:0}.h40-evidence small{font-size:13px;line-height:1.5;color:#5a7165}
.fact-reveal{margin:24px 0;padding:16px 18px;background:#e3eade;border-radius:13px}.fact-reveal summary{font-size:24px;font-weight:600;cursor:pointer;color:#1b6555}.fact-reveal p{font-size:23px;margin:15px 0 0}.h40-video{text-align:center}.h40-video video{display:block;width:min(100%,780px);height:34vh;max-height:380px;min-height:230px;object-fit:contain;background:#113c3d;margin:0 auto;border-radius:12px}.h40-video>p,.media-location{font-size:15px;line-height:1.5;margin:9px 0 0;text-align:center;color:#596f62}.media-alternative{font-size:15px;position:relative;margin:6px 0 0;text-align:center}.media-alternative summary{cursor:pointer;display:inline-block;color:#416d60;text-decoration:underline}.media-alternative[open]{background:#fffaf0;border:1px solid #b6c9b8;border-radius:10px;padding:12px 18px}.media-alternative p{font-size:17px;margin:10px 0}
.h40-recap{display:grid;grid-template-columns:repeat(3,1fr);gap:23px}.h40-recap article{padding:25px;background:#fffcf5;border:1px solid #c3d1c3;border-radius:16px}.h40-recap span{display:block;font-size:21px;color:#987032;margin-bottom:17px}.h40-recap h3{font-size:27px;line-height:1.5;margin-bottom:17px}.h40-recap p{font-size:23px;margin:0}.h40-recap-end{display:flex;align-items:center;gap:30px;margin-top:24px}.h40-recap-end p{font-size:23px;line-height:1.5;margin:0}
@media(max-height:760px) and (min-width:901px){.slide.history40{padding:20px 4vw}.history40 .slide-head{margin-bottom:16px}.history40 .activity-icon{width:52px;height:52px}.history40 h2{font-size:32px}.history40 .epoch{font-size:22px;margin-bottom:12px}.h40-grid{gap:25px}.history40 .lead{font-size:26px;margin-bottom:15px}.h40-grid p{font-size:21px;margin-bottom:12px}.h40-media img{height:33vh;min-height:165px}.h40-diagram svg{height:33vh}.inquiry{margin-top:16px;padding:13px 18px}.inquiry .ask{font-size:23px;margin-bottom:6px}.inquiry .support{font-size:18px}.h40-evidence{gap:8px}.h40-evidence article{padding:10px 15px;grid-template-columns:115px 1fr}.h40-evidence span{font-size:16px}.h40-evidence b{font-size:24px}.h40-evidence p{font-size:18px}.h40-location{padding:17px;gap:10px}.h40-location div{padding:24px 12px}.h40-location b{font-size:28px}.h40-location span{font-size:17px}.h40-route{padding:20px}.h40-route aside{padding-top:16px}.h40-route b{font-size:26px}.fact-quote{font-size:23px;padding:11px 16px;margin:13px 0}.h40-video video{height:33vh;min-height:220px}.h40-recap article{padding:20px}.h40-recap h3{font-size:22px}.h40-recap p{font-size:20px}.h40-recap-end p{font-size:21px}.fact-reveal{margin:17px 0;padding:13px 15px}.fact-reveal summary{font-size:23px}.fact-reveal p{font-size:21px}}
@media(max-width:900px){.h40-grid,.h40-artifacts,.h40-pair,.h40-recap{grid-template-columns:1fr}.slide.history40{padding:24px}.h40-media img{height:auto;max-height:45vh}.h40-video video{width:100%;height:auto;min-height:0}.h40-recap-end{flex-wrap:wrap}.inquiry .ask{font-size:25px}.inquiry .support{font-size:19px}.h40-location{grid-template-columns:1fr}.h40-location small{grid-column:auto}.h40-location>p{text-align:center}}

/* R2026-09-08.8: illustrated narration and evidence-based observation stops. */
.kind-intro > .h40-grid > .content-visual img{height:46vh;max-height:460px}
.kind-intro .h40-grid > div > .content-visual img{height:23vh;max-height:210px;min-height:0}
.kind-intro .h40-grid > div > .content-visual{margin:12px 0}
.slide.practice-illustrated{padding:28px 4vw;max-width:1700px}
.practice-illustrated .slide-head{gap:18px;margin-bottom:24px}
.practice-illustrated .slide-head h2{font-size:clamp(30px,3.1vw,48px)}
.practice-illustrated .activity-icon{width:64px;height:64px}
.practice-illustrated .h40-grid{grid-template-columns:1.25fr 1fr}
.practice-illustrated .content-visual img{height:44vh;max-height:460px}
.practice-copy .lead{font-size:clamp(26px,2.3vw,35px)}
.practice-copy p{font-size:clamp(21px,1.8vw,28px);line-height:1.6}
.practice-copy .small{font-size:20px;line-height:1.6;color:#4b6357}
.practice-copy .command{font-size:clamp(35px,3.1vw,50px);padding:16px 20px;letter-spacing:.04em;margin-bottom:18px}
.compact-rule{border-left:4px solid #b17d37;background:#fffbef;padding:12px 16px;margin-bottom:18px}
.compact-rule + .compact-rule{border-color:#16685e}
.compact-rule h3{font-size:clamp(24px,2vw,32px);margin-bottom:8px}
.compact-rule p{font-size:clamp(21px,1.6vw,25px);line-height:1.5;margin-bottom:8px}
.compact-rule small{font-size:18px;line-height:1.55;color:#4b6357}
.slide.rest{position:relative;isolation:isolate;overflow:hidden;max-width:none}
.slide.rest.active{align-items:flex-start;justify-content:center}
.rest .rest-art{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:-2}
.rest::before{content:"";position:absolute;inset:0;z-index:-1;background:linear-gradient(90deg,#103e40eb 0%,#103e40b8 45%,#103e4010 100%)}
.rest-copy{width:52%;text-align:left}
.rest-copy .slide-head{justify-content:flex-start}
.rest-copy p{color:#f7f0df}
.rest .rest-source{position:absolute;bottom:16px;right:25px;color:#fff6df;font-size:13px;margin:0;text-shadow:0 1px 4px #163c3c}
@media(max-height:760px) and (min-width:901px){
.kind-intro > .h40-grid > .content-visual img{height:45vh;max-height:370px}
.kind-intro .h40-grid > div > .content-visual img{height:20vh;max-height:160px}
.slide.practice-illustrated{padding:20px 4vw}
.practice-illustrated .slide-head{margin-bottom:16px}
.practice-illustrated .slide-head h2{font-size:32px}
.practice-illustrated .activity-icon{width:52px;height:52px}
.practice-copy .lead{font-size:27px}.practice-copy p{font-size:21px;margin-bottom:15px}
.practice-copy .small{font-size:19px}.practice-copy .command{font-size:36px}
.compact-rule{padding:10px 14px;margin-bottom:13px}.compact-rule h3{font-size:25px}.compact-rule p{font-size:21px;margin-bottom:7px}
}
@media(max-width:900px){
.practice-illustrated .h40-grid{grid-template-columns:1fr}.slide.practice-illustrated{padding:24px}
.kind-intro > .h40-grid > .content-visual img,.practice-illustrated .content-visual img{height:auto;min-height:0;max-height:50vh}
.rest-copy{width:100%}.rest::before{background:#103e40b8}.rest-copy .slide-head h2{font-size:29px}
}
.open-result-review .slide-head h2{font-size:clamp(32px,3.1vw,48px)}
.open-result-review .activity-icon{width:64px;height:64px}
.open-result-review .h40-pair img{height:35vh;max-height:390px}
.open-result-review .lead{font-size:clamp(25px,2.3vw,36px);margin:24px 0 8px}
.open-result-review .small{margin:0}
@media(max-height:760px) and (min-width:901px){.open-result-review .activity-icon{width:52px;height:52px}.open-result-review .slide-head h2{font-size:32px}.open-result-review .lead{font-size:26px;margin-top:19px}}
/* R2026-09-08.9: clear shared prompts; artifact introduction stays a narrated page. */
.kind-intro .h40-artifacts img{height:36vh;max-height:380px}
.artifact-intro{font-size:clamp(23px,2vw,31px);line-height:1.5;margin:24px 0 0}
.review-prompt{font-size:clamp(24px,2vw,32px);font-weight:600;line-height:1.45}
@media(max-height:760px) and (min-width:901px){.artifact-intro{font-size:23px;margin-top:18px}.review-prompt{font-size:23px}}

/* Search/planning comparison keeps a large legible diagram within the teaching page. */
.search-comparison .h40-media{margin:0 auto;max-width:1160px;width:100%}.search-comparison .h40-media img{width:100%;height:43vh;max-height:440px;object-fit:contain}.search-comparison .h40-media figcaption{font-size:13px}.search-comparison>.lead{font-size:clamp(24px,2.4vw,34px);margin:14px 0 8px}.search-comparison>.small{margin:10px 0 0}.practice-illustrated .practice-copy .primary+.primary{margin-top:8px}

/* R2026-09-09.3: grade variants retain shared image geometry and fixed text regions. */
.grade-adapted .practice-copy{align-self:center;min-width:0}.grade-adapted .grade-copy{min-height:350px;display:flex;flex-direction:column;justify-content:center}.grade-adapted .grade-copy>.primary,.grade-adapted .grade-copy>.button{align-self:flex-start}.grade-adapted .grade-copy>.primary:last-child{margin-top:4px}.grade-adapted .grade-goal,.grade-adapted .grade-required,.grade-adapted .grade-summary{font-size:clamp(23px,2vw,31px);font-weight:600;line-height:1.55;color:#185d52}.grade-adapted .grade-goal{border-left:4px solid #b17d37;padding-left:15px}.grade-adapted .h40-media img{object-fit:contain}.grade-adapted[data-slide-id=transfer] .content-visual img,.grade-adapted[data-slide-id=transfer_record] .content-visual img{height:55vh;max-height:540px}.grade-adapted .slide-head h2{min-height:1.3em}.grade-adapted .grade-copy p:last-child{margin-bottom:0}
@media(max-height:760px) and (min-width:901px){.grade-adapted .grade-copy{min-height:335px}.grade-adapted .grade-goal,.grade-adapted .grade-required,.grade-adapted .grade-summary{font-size:23px;line-height:1.5}.grade-adapted .grade-copy .lead{font-size:25px;line-height:1.5}.grade-adapted .grade-copy p{font-size:21px;line-height:1.55;margin-bottom:13px}.grade-adapted .grade-copy .small{font-size:18px;line-height:1.5}.grade-adapted .slide-head h2{font-size:30px}.grade-adapted[data-slide-id=transfer] .content-visual img,.grade-adapted[data-slide-id=transfer_record] .content-visual img{height:52vh;max-height:405px}}
@media(max-width:900px){.grade-adapted .grade-copy{min-height:0}.grade-adapted .grade-goal,.grade-adapted .grade-required,.grade-adapted .grade-summary{font-size:24px}.grade-adapted[data-slide-id=transfer] .content-visual img,.grade-adapted[data-slide-id=transfer_record] .content-visual img{height:auto;max-height:55vh}}
.grade-comparison .grade-copy{min-height:0;margin-top:15px}.grade-comparison .grade-copy p{margin-bottom:8px}.grade-comparison .h40-media img{height:34vh;max-height:360px}.grade-comparison .grade-copy .lead{font-size:clamp(23px,2.1vw,31px);line-height:1.4}.grade-comparison .grade-summary{font-size:clamp(22px,1.9vw,28px);line-height:1.4}.grade-comparison .grade-copy .small{font-size:18px;line-height:1.4}
@media(max-height:760px) and (min-width:901px){.grade-comparison .grade-copy{min-height:0;margin-top:10px}.grade-comparison .slide-head{margin-bottom:12px}.grade-comparison .grade-copy p{margin-bottom:5px}.grade-comparison .grade-copy .lead{font-size:23px;line-height:1.4}.grade-comparison .grade-summary{font-size:22px;line-height:1.4}.grade-comparison .h40-media img{height:32vh}.grade-comparison .grade-copy .small{font-size:17px}}


/* R2026-09-09.4 · Shared teacher navigation; retain responsive lesson layouts. */
#toolbar{height:68px;padding:10px 16px;gap:16px;background:#0b3438;color:#f7f2e8;border-top:1px solid #355c58}
#toolbar .nav-directory{flex:1;min-width:150px;max-width:300px}#pageSelect{width:100%;max-width:none}
#toolbar .nav-pagination,#toolbar .nav-settings{display:flex;align-items:center;gap:8px;flex:none}#toolbar .nav-pagination{justify-content:center}#toolbar .nav-settings{margin-left:auto}
#toolbar button,#toolbar select{font-family:'Microsoft YaHei',sans-serif;font-size:15px;padding:8px 11px;min-height:40px;border-radius:7px;background:#16484a;color:#f7f2e8;border-color:#53716b;font-weight:400}
#toolbar button:hover{background:#28645f}#toolbar #next{background:#e5ce9d;color:#153c39;border-color:#e5ce9d;font-weight:700}
#toolbar #prev,#toolbar #next{min-width:84px}#pageStatus{font-size:16px;min-width:68px;text-align:center;font-variant-numeric:tabular-nums;white-space:nowrap}#toolbar label{font-size:15px;white-space:nowrap}
#toolbar #grade{max-width:122px}#showBar{background:#0b3438;color:#f7f2e8;border-color:#53716b;font-size:15px;border-radius:7px;z-index:40}
#classroom{height:calc(100dvh - 68px)}#demoPanel{bottom:68px}body.bar-hidden #classroom{height:100dvh}body.bar-hidden #demoPanel{bottom:0}
.slide:not(.hero)>.slide-head h2{font-weight:700;line-height:1.25}
#helpDialog{padding:0;text-align:left;width:min(94vw,1050px);height:min(90dvh,850px)}#helpDialog[open]{display:flex;flex-direction:column}.help-top{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:16px 24px;background:#0b3438;color:#f7f2e8}.help-top h2{font-size:26px;line-height:1.3;margin:0}.help-top button{font-size:16px;background:#16484a;color:#f7f2e8;border-color:#53716b;padding:8px 14px}.help-body{padding:24px 30px;overflow:auto}.help-body p{font-size:20px;line-height:1.8;margin:0 0 20px}.help-body p:last-child{margin-bottom:0}
@media(max-width:1180px){#toolbar{gap:10px;padding:10px}#toolbar .nav-pagination,#toolbar .nav-settings{gap:6px}#toolbar .nav-directory{max-width:230px}#toolbar button,#toolbar select{font-size:14px;padding:8px}#toolbar label{display:none}#toolbar #prev,#toolbar #next{min-width:76px}#pageStatus{min-width:59px}}
@media(max-width:900px){#toolbar{height:112px;display:grid;grid-template-columns:1fr auto;align-content:center;gap:8px}#toolbar .nav-directory{max-width:none;min-width:0}#toolbar .nav-pagination{justify-self:end}#toolbar .nav-settings{grid-column:1/-1;justify-self:end;flex-wrap:wrap}#toolbar #prev,#toolbar #next{font-size:14px;min-width:76px}#classroom{height:calc(100dvh - 112px)}#demoPanel{bottom:112px}}
@media(max-width:600px){#toolbar{height:156px}#toolbar .nav-pagination{gap:4px}#toolbar #prev,#toolbar #next{font-size:12px;min-width:64px}#pageStatus{min-width:47px;font-size:13px}#toolbar .nav-settings{gap:4px;justify-content:flex-end}#toolbar .nav-settings button,#toolbar .nav-settings select{font-size:12px;padding:6px;min-height:36px}#classroom{height:calc(100dvh - 156px)}#demoPanel{bottom:156px}.help-body{padding:18px}.help-body p{font-size:17px}}

#toolbar .nav-settings{gap:6px}#toolbar .nav-settings button,#toolbar .nav-settings select{padding-left:9px;padding-right:9px}
@media(min-width:1200px){#toolbar .nav-pagination{position:absolute;left:50%;transform:translateX(-50%)}}

:root{--teacher-bar-height:68px}#toast{bottom:calc(var(--teacher-bar-height) + 16px)}
@media(max-width:900px){:root{--teacher-bar-height:112px}}
@media(max-width:600px){:root{--teacher-bar-height:156px}}
body.bar-hidden{--teacher-bar-height:0px}

@media(max-width:1400px){#toolbar label{display:none}}