@import url('data:text/css,');
:root{font-family:system-ui,-apple-system,BlinkMacSystemFont,"PingFang TC","Microsoft JhengHei",sans-serif;color:#183c43;background:#f4f8fa;font-synthesis:none;font-size:16px;--green:#175b49;--blue:#118ba7;--yellow:#ffd568;--line:#dce7e9;--muted:#526b73}
*{box-sizing:border-box}body{margin:0}button,input{font:inherit}button,a,input,summary{-webkit-tap-highlight-color:transparent}button{cursor:pointer}button:disabled{cursor:default;opacity:.5}button:focus-visible,a:focus-visible,input:focus-visible,summary:focus-visible{outline:3px solid #b06500;outline-offset:4px}button{touch-action:manipulation}a{color:inherit}button{color:inherit}button:active:not(:disabled){transform:translateY(1px)}.skip-link{position:fixed;top:-100px;left:16px;background:white;padding:16px;z-index:10}.skip-link:focus{top:8px}.site-header{height:90px;max-width:1280px;margin:auto;display:flex;align-items:center;justify-content:space-between;padding:0 36px;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-size:23px;font-weight:850;letter-spacing:1px}.brand small{display:block;font-size:12px;letter-spacing:2px;font-weight:500;color:var(--muted);margin-top:4px}.brand-mark{display:grid;place-items:center;width:46px;height:46px;border-radius:15px;background:var(--green);color:#b1f0e4;font-size:33px;font-weight:500}.header-end{display:flex;align-items:center;gap:24px}.age-tag{font-size:14px;color:var(--muted)}.icon-button{background:white;border:1px solid var(--line);border-radius:12px;min-height:44px;padding:9px 14px;font-weight:700;font-size:14px}main{max-width:1210px;padding:0 32px;margin:auto;outline:none}.chapter-nav{display:flex;align-items:center;gap:8px;padding:25px 0 20px;overflow-x:auto;scrollbar-width:thin}.chapter-pill{border:1px solid transparent;border-radius:100px;white-space:nowrap;padding:10px 15px;min-height:44px;background:transparent;font-size:14px;color:var(--muted);display:flex;gap:8px;align-items:center}.chapter-pill .nav-number{width:22px;height:22px;border-radius:50%;display:grid;place-items:center;background:#e0e9ec;font-size:12px;font-weight:800}.chapter-pill.active{background:var(--green);color:white}.chapter-pill.active .nav-number{background:#ffffff24;color:white}.chapter-pill.visited:not(.active) .nav-number{background:#cbe8dd;color:var(--green)}.chapter-heading{display:flex;justify-content:space-between;gap:20px;align-items:center;margin:6px 0 25px}.eyebrow{font-size:12px;letter-spacing:2px;color:var(--green);font-weight:800;margin:0 0 10px;display:flex;align-items:center;gap:10px}.eyebrow::before{content:"";display:inline-block;width:20px;height:3px;background:#25aaa3}.chapter-heading h1{font-size:clamp(28px,3.5vw,42px);line-height:1.25;letter-spacing:-1px;margin:0 0 12px;font-weight:850}.chapter-heading p{color:var(--muted);margin:0;line-height:1.65;font-size:16px}.chapter-position{flex:none;text-align:right;color:var(--muted);font-size:14px}.chapter-position strong{display:block;font-size:40px;font-weight:300;line-height:1.2;color:#b3c5c9}.workspace{display:grid;grid-template-columns:minmax(0,1fr) 320px;border:1px solid var(--line);border-radius:24px;overflow:hidden;background:white;box-shadow:0 8px 30px #133f4605}.stage{min-width:0;position:relative;background:#eef9f9;display:flex;flex-direction:column}.landscape{--rain-opacity:.5;--rain-speed:1s;--flow-speed:2s;--inflow-opacity:1;position:relative;height:100%;display:flex;flex-direction:column;min-height:495px;background:#f1faf9}.scene-top{display:flex;justify-content:space-between;align-items:center;padding:22px 22px 0;gap:10px;position:relative;z-index:1}.scene-tag{font-size:12px;color:#3a656c;font-weight:700;letter-spacing:1px}.weather-chip{font-size:14px;font-weight:600;padding:8px 12px;border-radius:99px;background:#ffffffb8;border:1px solid #ffffff;white-space:nowrap}.reservoir-svg{display:block;width:100%;height:auto;flex:1;min-height:0;max-height:490px}.diagram-label{fill:#284c49;font-size:26px;font-weight:750;font-family:inherit;paint-order:stroke;stroke:#f7faf0;stroke-width:4px;stroke-linejoin:round}.green-label{fill:#275a43}.lake-label{fill:white;stroke:#118dab;stroke-width:2px}.catchment-boundary{fill:none;stroke:#327257;stroke-width:3;stroke-dasharray:6 7}.stream-bed,.river-bed,.downstream-bed{fill:none;stroke:#5faab0;stroke-width:10;stroke-linecap:round}.river-bed{stroke-width:21}.downstream-bed{stroke-width:36;stroke:#b1d9db}.stream-flow,.river-flow,.downstream-flow{fill:none;stroke:#c4f8ff;stroke-width:5;stroke-linecap:round;stroke-dasharray:10 20;animation:flow var(--flow-speed) linear infinite;opacity:var(--inflow-opacity)}.river-flow{stroke-width:12;stroke:#72ddef}.downstream-flow{stroke:#27afcf;stroke-dasharray:18 13;animation-duration:1.4s}.rain-drop{stroke:#249ec4;stroke-width:3;stroke-linecap:round;animation:rain var(--rain-speed) linear infinite}#rain{opacity:var(--rain-opacity)}.city-pipe{fill:none;stroke:#78999b;stroke-width:9}.city-flow{fill:none;stroke:#56d4ec;stroke-width:5;stroke-dasharray:10 13;animation:flow 1s linear infinite}.scene-bottom{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:2px 24px 18px;margin-top:auto}.scene-bottom>span{max-width:70%;font-size:14px;line-height:1.5;color:#476b72}.level-badge{display:flex;gap:10px;align-items:center;padding:7px 11px;background:#ffffffc9;border-radius:12px;white-space:nowrap}.level-badge>span{font-size:12px}.level-badge strong{font-size:28px;color:#116c86;line-height:1.1;font-variant-numeric:tabular-nums}.level-badge small{font-size:14px;margin-left:2px}.water-gauge{height:6px;background:#d2e8eb}.water-gauge span{display:block;height:100%;background:#1bb5c7;transition:width .25s linear}.landscape.full .water-gauge span{background:#ed9e26}.landscape.full .level-badge strong{color:#986000}.control-panel{padding:26px;background:white;border-left:1px solid var(--line);display:flex;flex-direction:column;gap:20px;min-width:0}.control-panel h2{font-size:22px;line-height:1.4;margin:0}.control-panel p{font-size:16px;line-height:1.65;margin:0}.control-kicker{font-size:12px!important;font-weight:800;color:var(--green);letter-spacing:2px}.panel-hero{width:56px;height:56px;display:grid;place-items:center;background:#e5f3ee;border-radius:18px;font-size:29px;margin-bottom:-6px}.range-card{padding:18px 16px;background:#f3f7f8;border:1px solid #e4ecee;border-radius:16px}.range-title{display:flex;justify-content:space-between;gap:12px;font-size:16px;font-weight:700;margin-bottom:14px}.range-title output{color:#12728b}.range-labels{display:flex;justify-content:space-between;color:var(--muted);font-size:14px;margin-top:8px}.range-labels span{text-align:center}.range-input{appearance:none;-webkit-appearance:none;display:block;width:100%;height:44px;background:transparent;cursor:pointer;touch-action:pan-y;margin:0}.range-input::-webkit-slider-runnable-track{height:9px;border-radius:99px;background:#c9e3e6}.range-input::-moz-range-track{height:9px;border-radius:99px;background:#c9e3e6}.range-input::-webkit-slider-thumb{-webkit-appearance:none;width:30px;height:30px;background:var(--green);border:4px solid white;border-radius:50%;margin-top:-10px;box-shadow:0 0 0 1px #bcd4ce}.range-input::-moz-range-thumb{width:23px;height:23px;background:var(--green);border:4px solid white;border-radius:50%}.primary-button,.secondary-button,.choice-button{border:0;border-radius:13px;min-height:52px;padding:13px 18px;font-size:17px;font-weight:750;line-height:1.5}.primary-button{background:var(--green);color:white;box-shadow:0 3px 0 #104735}.secondary-button{background:#f0f5f6;border:1px solid var(--line)}.yellow-button{background:var(--yellow);color:#3d3b24;box-shadow:0 3px 0 #dfb750}.button-stack{display:grid;gap:10px}.choice-button{text-align:left;background:#f5f8f9;border:2px solid #e1eaed;display:flex;align-items:center;gap:12px;font-size:16px}.choice-button.selected{border-color:var(--green);background:#eaf5ee}.choice-icon{font-size:24px}.hint-box{background:#fff8df;padding:14px;border-radius:12px;font-size:15px;line-height:1.65;color:#675324}.panel-note{font-size:14px!important;color:var(--muted)}.concept-bar{display:flex;gap:14px;align-items:center;border:1px solid #d5e7de;background:#edf6f0;border-radius:16px;padding:17px 20px;margin-top:18px;font-size:16px;line-height:1.6}.concept-icon{flex:none;display:grid;place-items:center;width:35px;height:35px;border-radius:50%;background:#d5eadb;font-size:20px}.concept-bar p{margin:0}.more-details{padding:14px 4px 0;font-size:14px;color:var(--muted);line-height:1.8}.more-details summary{cursor:pointer;min-height:44px;display:list-item;padding-top:8px;font-weight:650;width:fit-content}.more-details p{max-width:850px;font-size:16px;line-height:1.85;margin:8px 0 14px}.bottom-nav{display:flex;justify-content:space-between;align-items:center;gap:12px;margin:18px 0 28px}.next-button{min-width:150px}.back-button{border:0;background:none;padding:12px 4px;min-height:44px;font-size:15px;color:var(--muted)}.site-footer{max-width:1146px;display:flex;justify-content:space-between;gap:16px;border-top:1px solid var(--line);padding:20px 0 28px;margin:0 auto;color:var(--muted);font-size:12px}.forecast-card{background:#f1f7f9;border:1px solid var(--line);border-radius:14px;padding:14px 16px;display:flex;align-items:center;gap:16px}.forecast-card>span{font-size:36px}.forecast-card small{display:block;font-size:14px;color:var(--muted);margin-bottom:4px}.forecast-card strong{font-size:19px}.journey-scene{padding-bottom:22px;min-height:495px;display:flex;flex-direction:column;background:#eef8fa}.journey-stops{display:grid;grid-template-columns:repeat(3,1fr);gap:30px 14px;padding:55px 28px 20px}.journey-stop{position:relative;display:flex;flex-direction:column;align-items:center;gap:12px;font-size:16px;color:#47616a;transition:opacity .3s;opacity:.45}.stop-icon{font-size:47px;display:grid;place-items:center;width:82px;height:82px;background:white;border:2px solid #d2e5e8;border-radius:23px}.journey-stop.active,.journey-stop.passed{opacity:1}.journey-stop.active .stop-icon{border-color:#1b9abc;box-shadow:0 0 0 5px #b3e8ec}.journey-stop.passed .stop-icon{background:#e1f1ed;border-color:#80bcb0}.stop-drop{position:absolute;font-size:25px;top:-26px;opacity:0}.journey-stop.active .stop-drop{opacity:1;animation:drop-hop 1s ease-in-out infinite}.journey-caption{font-size:17px;font-weight:650;line-height:1.65;margin:auto 20px 0;padding:17px;background:white;border-radius:14px;text-align:center}.treatment{display:flex;justify-content:center;gap:8px;padding:8px 16px 20px;flex-wrap:wrap}.treatment span{background:#dcecee;border:2px solid transparent;padding:10px 12px;border-radius:12px;font-size:14px}.treatment span.active{background:#fff2bb;border-color:#c39515}.treatment span.done{background:#d0ebda}.treatment[hidden]{display:none}.game-forecast{display:grid;grid-template-columns:repeat(7,minmax(0,1fr));gap:8px;margin-bottom:18px}.day-card{padding:10px 5px;text-align:center;background:white;border:1px solid var(--line);border-radius:13px;color:var(--muted);font-size:12px;position:relative}.day-card strong{display:block;font-size:25px;margin:5px 0}.day-card.today{background:#fff5d5;border:2px solid #dfb34f;padding:9px 4px;color:#6b4e12}.day-card.past{background:#eaf0ef}.day-card.past::after{content:'✓';position:absolute;top:3px;right:6px;color:#256745;font-weight:800}.game-choices{display:grid;grid-template-columns:1fr 1fr;gap:8px}.game-choices .choice-button{font-size:14px;padding:10px;min-height:56px;display:block;text-align:center}.game-choices .choice-button span{display:block;font-size:23px;margin-bottom:3px}.day-status{min-height:62px;font-size:15px!important;color:#36535c}.phase-label{padding:10px 12px;border-radius:12px;background:#e7f4f7;color:#116d83;font-weight:700}.game-result{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;min-height:495px;padding:32px 25px;background:#edf8f3}.result-icon{font-size:74px;margin-bottom:15px}.game-result h2{font-size:32px;margin:0 0 14px}.game-result p{font-size:17px;line-height:1.7;margin:0;max-width:460px}.mini-history{display:flex;align-items:flex-end;height:100px;gap:14px;padding:0 12px;margin:26px 0 12px;width:100%;max-width:420px}.history-col{flex:1;text-align:center;display:flex;flex-direction:column;justify-content:flex-end;height:100%;font-size:12px;gap:5px}.history-col .bar{background:#29b1c5;border-radius:5px 5px 0 0;width:100%;min-height:2px}.history-col.warning .bar{background:#e4a334}.quiz-stage{min-height:495px;display:flex;flex-direction:column;align-items:center;justify-content:center;padding:30px;text-align:center;background:#edf8fa}.quiz-symbol{font-size:92px;margin-bottom:22px}.quiz-stage h2{font-size:26px;line-height:1.5;max-width:420px;margin:0 0 20px}.quiz-dots{display:flex;gap:10px;margin-bottom:25px}.quiz-dot{width:12px;height:12px;border-radius:50%;background:#c4dfe3}.quiz-dot.done{background:var(--green)}.quiz-dot.current{background:#e5b53d;box-shadow:0 0 0 4px #fbebbe}.quiz-feedback{min-height:70px;font-size:17px;line-height:1.7;max-width:440px;padding:16px;border-radius:14px;background:#fff}.quiz-symbol.rain{animation:drop-hop 1.3s infinite}.quiz-symbol.dry{opacity:.6}.quiz-symbol.space{transform:scale(.8)}.quiz-symbol.clean{filter:saturate(1.4)}.score-pills{display:flex;gap:12px;flex-wrap:wrap;justify-content:center;margin-top:20px}.score-pills span{padding:10px 14px;background:white;border:1px solid #bed8c8;border-radius:12px;font-size:14px}.paused .rain-drop,.paused .stream-flow,.paused .river-flow,.paused .downstream-flow,.paused .city-flow,.paused .stop-drop,.paused .quiz-symbol{animation-play-state:paused}button,summary{transition:background .15s}.muted{color:var(--muted)}[hidden]{display:none!important}
@keyframes flow{to{stroke-dashoffset:-60}}@keyframes rain{from{transform:translate(0,-6px);opacity:.2}to{transform:translate(-12px,54px);opacity:1}}@keyframes drop-hop{50%{transform:translateY(-7px)}}
@media(min-width:1400px){main{padding:0 32px}.chapter-heading{margin-top:16px;margin-bottom:30px}.workspace{grid-template-columns:minmax(0,1fr) 330px}.landscape,.journey-scene,.game-result,.quiz-stage{min-height:525px}.control-panel{padding:30px}}
@media(max-width:900px){.site-header{padding:0 24px;height:80px}main{padding:0 24px}.chapter-nav{gap:3px;padding:20px 0}.chapter-pill{padding:9px 12px}.workspace{grid-template-columns:minmax(0,1fr) 275px}.control-panel{padding:20px;gap:17px}.scene-top{padding:16px 14px 0}.scene-tag{font-size:12px}.weather-chip{font-size:12px;padding:7px 9px}.scene-bottom{padding:5px 14px 18px;gap:6px}.scene-bottom>span{font-size:13px;max-width:60%}.level-badge{display:block;text-align:center}.level-badge>span{display:block}.level-badge strong{font-size:24px}.site-footer{margin:0 24px}.journey-stops{padding:42px 12px 24px;gap:34px 8px}.stop-icon{width:68px;height:68px;font-size:40px}.journey-stop{font-size:14px}}
@media(max-width:680px){.site-header{padding:0 18px;height:75px}.brand{font-size:20px;gap:9px}.brand-mark{width:39px;height:39px;border-radius:12px;font-size:29px}.brand small{font-size:11px;letter-spacing:1px}.header-end{gap:0}.age-tag{display:none}.icon-button{padding:9px 11px}.icon-button span{font-size:13px}main{padding:0 16px}.chapter-nav{padding:17px 0 19px;margin-right:-16px}.chapter-pill{font-size:13px;gap:6px;padding:8px 12px}.chapter-heading{margin:4px 0 21px}.eyebrow{font-size:11px;margin-bottom:9px}.chapter-heading h1{font-size:28px;letter-spacing:-.5px;margin-bottom:10px}.chapter-heading p{font-size:15px;max-width:285px}.chapter-position{display:none}.workspace{display:flex;flex-direction:column;border-radius:20px}.landscape{min-height:0}.reservoir-svg{height:auto;flex:none;max-height:none;aspect-ratio:900/570}.scene-top{padding:15px 14px 0}.scene-tag{font-size:11px}.scene-bottom{padding:0 14px 15px;min-height:60px}.scene-bottom>span{font-size:14px;max-width:67%}.level-badge{display:flex;gap:5px;padding:8px}.level-badge>span{font-size:11px}.level-badge strong{font-size:23px}.control-panel{border-left:0;border-top:1px solid var(--line);padding:22px;gap:16px}.panel-hero{display:none}.control-panel h2{font-size:21px}.control-panel p{font-size:16px}.control-kicker{display:none}.range-card{padding:12px 16px}.range-title{margin-bottom:4px}.button-stack{grid-template-columns:1fr 1fr}.button-stack.vertical{grid-template-columns:1fr}.choice-button{font-size:15px;padding:12px;gap:7px}.choice-icon{font-size:20px}.concept-bar{font-size:15px;padding:15px 16px;gap:10px;margin-top:14px;align-items:flex-start}.concept-icon{width:30px;height:30px;font-size:17px}.bottom-nav{margin:12px 0 24px}.next-button{min-width:140px;font-size:16px}.more-details{padding-top:6px}.site-footer{margin:0 16px;flex-direction:column;gap:8px;padding:18px 0 22px}.journey-scene{min-height:400px;padding-bottom:16px}.journey-stops{padding:40px 15px 26px;gap:35px 10px}.journey-stop{font-size:14px;gap:10px}.stop-icon{width:66px;height:66px;font-size:38px;border-radius:18px}.journey-caption{font-size:16px;margin:0 14px}.treatment{padding-bottom:16px;gap:6px}.treatment span{font-size:13px;padding:8px}.game-forecast{gap:4px;margin-bottom:14px}.day-card{font-size:11px;padding:8px 2px;border-radius:10px}.day-card strong{font-size:21px}.day-card.today{padding:7px 1px}.game-choices{grid-template-columns:repeat(4,1fr);gap:5px}.game-choices .choice-button{font-size:13px;padding:8px 3px;min-height:65px}.game-choices .choice-button span{font-size:21px}.game-result,.quiz-stage{min-height:380px;padding:28px 20px}.game-result h2{font-size:27px}.result-icon{font-size:62px}.quiz-symbol{font-size:70px;margin-bottom:14px}.quiz-stage h2{font-size:23px}.quiz-feedback{font-size:16px;padding:12px}.mini-history{height:90px;gap:9px}.score-pills{gap:8px}.score-pills span{font-size:13px}}
@media(max-width:350px){main{padding:0 12px}.site-header{padding:0 12px}.chapter-heading h1{font-size:25px}.control-panel{padding:18px}.scene-bottom{padding:0 10px 12px}.scene-bottom>span{font-size:13px}.level-badge{display:block}.choice-button{font-size:14px}.game-choices{grid-template-columns:1fr 1fr}.journey-stop{font-size:13px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}.stream-flow,.river-flow,.downstream-flow,.city-flow{stroke-dasharray:none}.rain-drop{opacity:1}.quiz-symbol{transform:none!important}}
@media(max-width:900px){.diagram-label{font-size:32px}}
@media(max-width:680px){.diagram-label{font-size:44px}}