:root{--ink:#203832;--green:#173e37;--green-light:#e8eee6;--paper:#f8f7f2;--white:#fff;--line:#e0e4db;--muted:#69766e;--accent:#d8e7ad;--orange:#96642b;--orange-light:#fcf1de;--red:#a24f42;--red-light:#faefec;--radius:18px;--shadow:0 6px 24px #19372b06;--font:"Microsoft YaHei UI","Microsoft YaHei","PingFang SC","Segoe UI",sans-serif;--math:"Cambria Math","Segoe UI Symbol","Microsoft YaHei",sans-serif}
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20px}.layout{display:grid;grid-template-columns:230px minmax(0,1fr);min-height:100vh}.sidebar{background:var(--green);color:#fff;display:flex;flex-direction:column;padding:30px 23px;position:sticky;top:0;height:100vh}.brand{display:flex;gap:12px;align-items:center;margin-bottom:40px}.brand-mark{width:43px;height:43px;border-radius:13px;background:var(--accent);color:var(--green);display:grid;place-items:center;font:30px var(--math);flex-shrink:0}.brand-name{font-size:17px;font-weight:700;letter-spacing:.5px}.brand-sub{font-size:11px;color:#b8cdc3;letter-spacing:1px}.side-label{font-size:11px;letter-spacing:2px;color:#a8bfb4;margin-bottom:13px}.flow-nav{display:flex;flex-direction:column;gap:8px}.nav-step{display:flex;align-items:center;gap:12px;border:0;background:transparent;color:#b8cdc3;text-align:left;padding:12px 9px;border-radius:10px;font-size:13px}.nav-step .number{font-size:11px;border:1px solid #638578;width:24px;height:24px;display:grid;place-items:center;border-radius:50%;flex-shrink:0}.nav-step.active{background:#ffffff16;color:white}.nav-step.active .number{background:var(--accent);border-color:var(--accent);color:var(--green)}.nav-step.done .number{color:var(--accent);border-color:var(--accent)}.nav-step:disabled{opacity:.37}.side-note{margin-top:auto;padding-top:30px;font-size:11px;line-height:1.9;color:#adc2b7}.side-note strong{display:block;color:#dfeadf;font-size:12px;font-weight:500;margin-bottom:6px}.workspace{min-width:0}.topbar{min-height:80px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;gap:12px;padding:17px 38px;background:#ffffff88}.breadcrumb{font-size:12px;color:var(--muted)}.breadcrumb 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#dde5d1;border-radius:var(--radius);padding:35px 38px;margin-bottom:27px;display:grid;grid-template-columns:1fr 150px;align-items:center;gap:24px}.hero h1{font-size:34px}.hero p{margin-top:13px;max-width:560px;color:#586b5e}.hero-art{font-family:var(--math);font-size:70px;text-align:center;color:#789477;position:relative}.hero-art::before{content:"";position:absolute;inset:-45px;background-image:linear-gradient(#8ea98820 1px,transparent 1px),linear-gradient(90deg,#8ea98820 1px,transparent 1px);background-size:20px 20px;transform:rotate(-10deg);border-radius:50%}.hero-art span{position:relative}.section-title{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:17px}.section-title p{font-size:12px;color:var(--muted)}.filters{display:grid;grid-template-columns:1fr 1fr 1.5fr;gap:15px;margin-bottom:22px}.field-label{display:block;font-size:12px;color:var(--muted);margin-bottom:7px}select,textarea{width:100%;border:1px solid var(--line);background:white;color:var(--ink);border-radius:10px;padding:10px 12px}select{min-height:43px}.chain-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.chain-card{background:white;border:1px solid var(--line);border-radius:var(--radius);padding:27px;box-shadow:var(--shadow);display:flex;flex-direction:column;gap:17px}.chain-top{display:flex;justify-content:space-between;align-items:center}.stage-label{font-size:12px;color:var(--muted)}.chain-card h2{font-size:20px}.chain-card p{color:var(--muted);font-size:13px}.chain-path{background:var(--paper);padding:15px;border-radius:10px;font-size:12px;color:#557063}.chain-path span{display:block;margin-bottom:4px;font-size:10px;color:var(--muted)}.chain-meta{display:flex;gap:15px;font-size:11px;color:var(--muted)}.chain-card .button{align-self:flex-start;margin-top:auto}.button{border:1px solid var(--green);background:var(--green);color:white;border-radius:10px;padding:11px 19px;min-height:45px;font-size:13px;font-weight:500;display:inline-flex;align-items:center;justify-content:center;gap:10px;text-decoration:none}.button:hover:not(:disabled){background:#23564b}.button.secondary{background:white;color:var(--green);border-color:var(--line)}.button.secondary:hover:not(:disabled){background:var(--green-light)}.button.soft{background:var(--green-light);color:var(--green);border-color:transparent}.link-button{background:transparent;border:0;color:var(--green);font-size:12px;padding:4px 0;text-decoration:underline;text-underline-offset:4px}.resume{display:flex;align-items:center;justify-content:space-between;gap:18px;margin-top:22px;padding:19px 22px;border:1px dashed #a7b89f;border-radius:12px}.footer{color:var(--muted);font-size:11px;text-align:center;margin-top:29px}.learning-grid{display:grid;grid-template-columns:minmax(0,1fr) 245px;gap:24px;align-items:start}.panel{border:1px solid var(--line);border-radius:var(--radius);background:white;padding:25px;box-shadow:var(--shadow);margin-bottom:20px;min-width:0}.panel:last-child{margin-bottom:0}.panel-heading{display:flex;justify-content:space-between;align-items:center;gap:12px;margin-bottom:18px}.panel-heading small{color:var(--muted)}.question-stem{font-family:var(--math);font-size:24px;line-height:1.8;margin:13px 0 22px;overflow-wrap:anywhere}.options{display:grid;gap:11px;border:0;padding:0;margin:0 0 22px;min-width:0}.option{border:1px solid var(--line);border-radius:11px;padding:14px;display:flex;align-items:center;gap:11px;cursor:pointer;background:#fff}.option:hover{background:var(--paper)}.option:has(input:checked){border-color:#658d63;background:#edf3e8}.option input{accent-color:var(--green);margin:0;flex-shrink:0}.option .letter{font-size:11px;color:var(--muted)}.option .math{overflow-wrap:anywhere}.actions{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-top:20px}.actions .caption{font-size:11px;color:var(--muted)}.hint-panel{background:var(--orange-light);border:1px solid #ecdec3;border-radius:12px;padding:17px 19px;margin-top:20px}.hint-panel p{font-size:12px;color:#846c47}.hint-panel ul{padding-left:19px;font-size:13px;color:#715632;margin:12px 0}.hint-panel .link-button{color:var(--orange)}.rail{position:sticky;top:24px}.rail .panel{padding:20px}.rail h3{margin-bottom:14px}.stat-row{display:flex;justify-content:space-between;gap:12px;color:var(--muted);font-size:12px;margin:10px 0}.stat-row strong{color:var(--ink);font-weight:500;font-size:16px}.rail progress{width:100%;height:7px;accent-color:var(--green);border-radius:10px;overflow:hidden}.rail progress::-webkit-progress-bar{background:var(--green-light);border-radius:10px}.rail progress::-webkit-progress-value{background:#698466;border-radius:10px}.rail-note{font-size:11px;color:var(--muted);margin-top:13px;line-height:1.9}.mini-evidence{font-size:11px;border-top:1px solid var(--line);padding:10px 0}.mini-evidence span{display:block;margin-bottom:4px}.result{border-left:3px solid #678f61;padding:4px 0 5px 18px;margin:22px 0}.result.incorrect{border-color:var(--red)}.result h3{margin-bottom:9px}.steps{padding-left:23px;color:#4e6557;font-size:13px;line-height:2;margin:10px 0}.steps li{padding-left:3px;margin-bottom:5px}.error-note{font-size:12px;color:var(--red);background:var(--red-light);border-radius:8px;padding:12px;margin:14px 0}.evidence-list{display:grid;gap:11px}.evidence-row{padding:14px 0;border-bottom:1px solid var(--line)}.evidence-row:last-child{border:0}.evidence-row .row-top{display:flex;align-items:center;justify-content:space-between;gap:12px}.evidence-row p{margin-top:8px;font-size:13px}.data-caption{font-size:10px;color:var(--muted);margin-top:8px}.callout{background:var(--green-light);border-radius:11px;padding:16px 19px;font-size:12px;color:#4e6858;margin:18px 0}.callout.amber{background:var(--orange-light);color:#816331}.diagnosis-row{padding:17px 0;border-bottom:1px solid var(--line)}.diagnosis-row:last-child{border:0}.diagnosis-row h3{display:flex;justify-content:space-between;gap:12px;margin-bottom:8px}.diagnosis-row p{font-size:12px;color:var(--muted)}.confirm-options{display:grid;gap:12px;margin:16px 0}.check-row{display:flex;align-items:flex-start;gap:10px;padding:15px;border:1px solid var(--line);border-radius:10px;cursor:pointer}.check-row input{margin-top:5px;accent-color:var(--green)}.ack{font-size:12px;color:var(--muted);display:flex;gap:9px;align-items:flex-start;margin-top:18px}.ack input{accent-color:var(--green);margin-top:5px}.lesson{border:1px solid var(--line);border-radius:12px;margin-bottom:15px;overflow:hidden}.lesson summary{padding:16px 18px;cursor:pointer;background:#f3f5ec;font-weight:500}.lesson-body{padding:18px}.lesson-rule{font-family:var(--math);font-size:18px;color:var(--green);margin-bottom:9px}.lesson-body>p{font-size:12px;color:var(--muted)}.worked{background:var(--paper);border-radius:10px;padding:16px;margin-top:18px}.worked h3{font-size:13px}.practice-levels{display:flex;gap:9px;margin-bottom:20px}.level-pill{padding:6px 14px;border:1px solid var(--line);border-radius:20px;font-size:12px;color:var(--muted)}.level-pill.active{color:var(--green);background:var(--green-light);border-color:#b9cfb1}.report-metrics{display:grid;grid-template-columns:repeat(3,1fr);gap:15px;margin-bottom:24px}.metric{padding:22px;background:white;border:1px solid var(--line);border-radius:14px}.metric p{font-size:12px;color:var(--muted)}.metric strong{font-size:32px;display:block;margin:4px 0;font-weight:500}.metric small{font-size:10px;color:var(--muted)}.report-evidence{border-bottom:1px solid var(--line);padding:13px 0}.report-evidence:last-child{border:0}.report-evidence summary{cursor:pointer;display:flex;align-items:center;justify-content:space-between;gap:15px;font-size:13px}.report-evidence summary .badge{flex-shrink:0}.report-evidence[open] summary{margin-bottom:13px}.report-evidence .math{display:block;margin-top:12px}.review-plan{display:grid;grid-template-columns:repeat(3,1fr);gap:13px;margin-top:17px}.review-date{padding:17px;background:var(--paper);border-radius:10px}.review-date small{color:var(--muted);font-size:10px}.review-date strong{display:block;font-size:14px;margin:7px 0}.review-date p{font-size:11px;color:var(--muted)}.empty{padding:35px;background:white;border:1px dashed var(--line);border-radius:14px;color:var(--muted)}#notice{position:fixed;bottom:25px;left:50%;transform:translateX(-50%);max-width:90vw;background:var(--green);color:white;border-radius:10px;box-shadow:0 4px 20px #0002;z-index:20;font-size:12px;padding:0;pointer-events:none}#notice:not(:empty){padding:12px 19px}.error-banner{padding:15px 20px;background:var(--red-light);border:1px solid #dec2ba;border-radius:12px;color:var(--red);margin-bottom:20px}.error-banner button{margin-left:12px}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap}
@media(min-width:1500px){.content{padding-top:40px}.hero{padding:44px}.learning-grid{grid-template-columns:minmax(0,1fr) 285px}}
@media(max-width:1120px){.layout{grid-template-columns:190px minmax(0,1fr)}.sidebar{padding:25px 16px}.content{padding:28px 24px}.topbar{padding:16px 24px}.learning-grid{grid-template-columns:minmax(0,1fr) 205px;gap:16px}.chain-card{padding:23px}.panel{padding:21px}.brand-name{font-size:15px}}
@media(max-width:900px){.learning-grid{grid-template-columns:minmax(0,1fr)}.rail{position:static;display:grid;grid-template-columns:1fr 1fr;gap:15px}.rail .panel{margin:0}.chain-grid{grid-template-columns:1fr}.hero-art{display:none}.hero{grid-template-columns:1fr;padding:28px}.hero h1{font-size:29px}.report-metrics{gap:9px}.metric{padding:17px}.filters{grid-template-columns:1fr 1fr}.filters>label:last-child{grid-column:1/-1}}
@media(max-width:650px){.layout{display:block}.sidebar{position:static;height:auto;padding:16px 18px}.brand{margin-bottom:14px}.brand-mark{width:34px;height:34px;font-size:25px;border-radius:10px}.side-label,.side-note{display:none}.flow-nav{flex-direction:row;overflow-x:auto;gap:5px;padding-bottom:4px}.nav-step{padding:7px 10px;white-space:nowrap;font-size:11px;gap:6px}.nav-step .number{width:20px;height:20px;font-size:9px}.topbar{min-height:64px;padding:13px 18px}.breadcrumb{font-size:10px;max-width:63%}.profile p{font-size:11px}.profile small{font-size:9px}.content{padding:22px 17px}.hero{padding:25px 22px;margin-bottom:22px}.hero h1{font-size:27px}.hero p{font-size:12px}.page-heading h1{font-size:24px}.page-heading p{font-size:12px}.chain-card{padding:22px}.filters{gap:11px}.section-title h2{font-size:17px}.section-title p{font-size:10px}.panel{padding:20px 18px}.question-stem{font-size:21px}.option{padding:13px 11px}.rail{grid-template-columns:1fr}.report-metrics{grid-template-columns:1fr 1fr 1fr;gap:7px}.metric{padding:13px 10px}.metric strong{font-size:26px}.metric p{font-size:10px}.metric small{font-size:9px}.review-plan{grid-template-columns:1fr}.diagnosis-row h3{flex-wrap:wrap}.report-evidence summary{font-size:12px;gap:10px}.resume{align-items:flex-start;flex-direction:column}.ack{font-size:11px}.button{font-size:12px}.learning-grid{gap:20px}}
@media(prefers-reduced-motion:reduce){*{transition:none!important;scroll-behavior:auto!important}}
@media print{.sidebar,.topbar,.footer,.actions,.rail,#notice,.page-heading .badge{display:none}.layout,.learning-grid{display:block}.content{padding:0}.panel,.metric{box-shadow:none;break-inside:avoid}.report-evidence{break-inside:avoid}}

input[type=search],.editor input:not([type=radio]):not([type=checkbox]){width:100%;min-width:0;border:1px solid var(--line);background:white;border-radius:10px;padding:11px 12px;color:var(--ink);font:inherit}
.role-switch{display:flex;gap:6px;flex-wrap:wrap;align-items:center;justify-content:center}.role-switch small{flex-basis:100%;text-align:center;color:var(--muted);font-size:10px}.role-button,.filter-chip{border:1px solid var(--line);background:white;border-radius:9px;padding:8px 12px;color:var(--muted);font-size:12px}.role-button.active,.filter-chip.active{background:var(--green-light);border-color:#b9cfb1;color:var(--green)}
.chip-group{display:flex;flex-wrap:wrap;gap:8px;margin:10px 0 16px}.finder{margin-top:18px}.review-cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}.mini-card{border:1px solid var(--line);border-radius:12px;padding:18px;background:var(--paper);min-width:0}.mini-card h3{overflow-wrap:anywhere}.record-row{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:15px 0;border-bottom:1px solid var(--line)}.record-row p{font-size:12px}.record-row>div{min-width:0;overflow-wrap:anywhere}.record-row .button{flex-shrink:0}.editor form>.field-label{margin:16px 0;font-size:13px}.editor input,.editor textarea{margin-top:7px}.choice-cards{display:flex;flex-wrap:wrap;gap:10px;border:1px solid var(--line);border-radius:12px;padding:15px;margin:16px 0;min-width:0}.choice-cards legend{font-size:13px;color:var(--muted)}.choice-card{display:flex;align-items:center;gap:8px;padding:10px 13px;border:1px solid var(--line);border-radius:10px;cursor:pointer;min-width:0;font-size:12px}.choice-card:has(input:checked){background:var(--green-light);border-color:#b9cfb1}.choice-card input{accent-color:var(--green)}.choice-card span{overflow-wrap:anywhere}.choice-card small{display:block;color:var(--muted)}.admin-grid .chain-card h2,.admin-grid .chain-card p{overflow-wrap:anywhere}.admin-grid details{font-size:12px}.admin-grid .actions{margin:0}.chain-meta{flex-wrap:wrap}.topbar{gap:14px}.topbar .breadcrumb{flex-shrink:1}.editor{scroll-margin-top:24px}
@media(max-width:1120px){.profile{display:none}.topbar{flex-wrap:wrap}.role-switch{justify-content:flex-start}.role-switch small{text-align:left}}
@media(max-width:650px){.topbar{align-items:flex-start;flex-direction:column}.breadcrumb{max-width:100%}.role-switch{width:100%}.role-button{flex:1;padding:8px 6px}.review-cards{grid-template-columns:1fr}.record-row{align-items:flex-start;flex-direction:column}.choice-card{max-width:100%}.chain-top{flex-wrap:wrap;gap:8px}.filter-chip{padding:9px 11px}.editor .actions .button{width:100%}}

.classroom-bar{display:flex;flex-wrap:wrap;gap:18px;align-items:center;border:2px solid #b5d0bb}.classroom-bar .rail-note{flex-basis:100%;margin:0}.clock{font-size:1.6rem;font-variant-numeric:tabular-nums}.classroom-bar small{display:block}.prewrap{white-space:pre-wrap;overflow-wrap:anywhere}.readonly{opacity:.65}.role-switch{flex-wrap:wrap}.assign-form{margin-top:16px}.worked form{margin:18px 0}.worked fieldset{margin:14px 0}.mini-card,.evidence-row{overflow-wrap:anywhere}.mini-card form input,.worked textarea{max-width:100%}

.observe-table{border-collapse:collapse;width:100%;max-width:400px;margin:18px 0}.observe-table th,.observe-table td{border:1px solid #d8e1dc;padding:10px;text-align:center}.prewrap{white-space:pre-wrap;overflow-wrap:anywhere}.question-stem{overflow-wrap:anywhere}textarea,select{max-width:100%;box-sizing:border-box}details p{overflow-wrap:anywhere}

.v4-entry{margin:0 0 34px}.v4-entry-heading{display:flex;justify-content:space-between;align-items:flex-start;gap:20px;margin-bottom:20px}.v4-version{display:inline-block;color:#21574a;background:#e7f0db;padding:7px 12px;border-radius:8px;font-weight:700}.v4-entry h1{font-size:clamp(26px,3vw,38px);line-height:1.25;margin:14px 0 10px}.v4-entry-heading p{margin:0;max-width:730px;line-height:1.7;color:#566d65}.v4-featured{margin-bottom:12px}.v4-lesson-card{border:2px solid #abc6b1;background:#fff}.v4-lesson-card h2{font-size:23px;margin:15px 0}.v4-lesson-code{font-weight:750;color:#20594d}.v4-learning-path{font-size:13px;line-height:1.7;color:#546d61;background:#f2f5ec;border-radius:8px;padding:9px 12px;margin:10px 0 16px}.v4-entry-note{font-size:13px;line-height:1.7;color:#63776d}.v4-featured .button{width:100%}@media(max-width:700px){.v4-entry-heading{display:block}.v4-entry-heading>.badge{margin-top:12px}.v4-lesson-card h2{font-size:21px}.v4-entry h1{font-size:27px}.v4-featured{grid-template-columns:1fr}.v4-entry-heading p{font-size:14px}}
/* Geometry classroom: original diagram-led layout inspired by the reviewed reference. */
.geometry-app{min-height:100vh;background:#f4f7fb;color:#26374a;font-family:"Microsoft YaHei",system-ui,sans-serif}.geo-header{min-height:78px;background:#fff;border-bottom:1px solid #e5ebf2;display:flex;align-items:center;gap:32px;padding:15px 28px;flex-wrap:wrap}.geo-brand{font-size:19px;font-weight:800;color:#173754;text-decoration:none;white-space:nowrap}.geo-brand span{color:#2187cb;font-size:27px;margin-right:6px}.geo-header nav{display:flex;gap:5px;flex:1}.geo-header button{border:0;background:transparent;color:#647287;padding:11px 13px;font-size:14px;cursor:pointer;border-radius:6px}.geo-header button.active{background:#e8f4fe;color:#1679b7;font-weight:700}.geo-role{display:flex;gap:2px}.geo-role button{padding:7px;font-size:12px}.geo-main{max-width:1200px;margin:auto;padding:30px 28px}.geo-home-title{margin:0 0 25px}.geo-kicker{font-size:13px;letter-spacing:.12em;color:#2586bc}.geo-home-title h1{font-size:36px;margin:8px 0 10px;line-height:1.2}.geo-home-title p{font-size:16px;color:#6a7788;margin:0}.geo-topic-cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:22px}.geo-topic-card{background:#fff;border:1px solid #dbe5ee;border-radius:12px;overflow:hidden;box-shadow:0 5px 18px #243b5310}.geo-topic-card>.geo-figure{border:0;border-radius:0;background:#f7fbff;margin:0;height:180px}.geo-topic-card>.geo-figure svg{width:100%;height:100%;min-height:0}.geo-topic-card>div:last-child{padding:20px 23px 25px}.geo-topic-number{font-size:12px;color:#3b93c8;font-weight:800}.geo-topic-card h2{font-size:22px;margin:6px 0 12px}.geo-topic-card p{font-size:14px;color:#6c7a8b;margin-bottom:23px}.geometry-app .button{border-radius:5px;background:#268ccc;border-color:#268ccc;min-height:42px;padding:10px 23px;font-size:15px}.geometry-app .button.secondary{background:#fff;border:1px solid #ccdce8;color:#4b6a83}.geo-topic-card .button{width:100%}.geo-home-note{font-size:13px;color:#7b8795;margin:20px 0}.geo-history{margin:20px 0;background:#fff;border:1px solid #e0e7ef;border-radius:8px;padding:16px}.geo-history>summary{cursor:pointer;color:#637790}.geo-history .v4-entry{padding-top:25px}.geo-footer{max-width:1200px;padding:20px 28px;margin:auto;font-size:12px;color:#8a95a2}.geo-workspace{display:grid;grid-template-columns:185px minmax(0,1fr);gap:25px}.geo-sidebar{align-self:start;background:#fff;border:1px solid #e0e8ef;border-radius:8px;padding:18px 12px}.geo-sidebar>p{font-size:12px;color:#8c98a5;margin:0 8px 9px}.geo-sidebar h2{font-size:17px;line-height:1.5;margin:0 8px 20px}.geo-sidebar nav{display:grid;gap:6px}.geo-sidebar nav button{border:0;padding:13px 10px;display:flex;gap:12px;align-items:center;background:#f3f6f8;border-radius:4px;text-align:left;font-size:14px;cursor:pointer;color:#536575}.geo-sidebar nav button.active{background:#49a5dc;color:white}.geo-sidebar nav span{font-size:12px}.geo-center-link{background:none;border:0;color:#66829a;font-size:13px;padding:22px 0 5px;cursor:pointer}.geo-sidebar>.button{font-size:13px;padding:7px;margin-top:15px;width:100%}.geo-body{min-width:0}.geo-class-status{background:#eaf4fb;border:1px solid #d3e8f6;border-radius:7px;display:flex;align-items:center;justify-content:space-between;gap:10px;padding:9px 16px;margin-bottom:14px;font-size:13px}.geo-class-status span{margin:0 18px 0 9px;color:#5b7e97}.geo-class-status b{font-variant-numeric:tabular-nums;font-size:17px;color:#236c9e}.geo-class-status .button{min-height:30px;padding:5px 12px;margin-left:5px;font-size:12px}.geo-paper{padding:25px 30px;background:#fff;border:1px solid #dfe7ef;border-radius:9px;box-shadow:0 4px 15px #21425708}.geo-paper-heading{position:relative;margin-bottom:12px}.geo-paper-heading>span{color:#8794a0;font-size:12px}.geo-paper-heading h1{font-size:23px;font-weight:650;line-height:1.6;margin:8px 35px 4px 0}.geo-star{position:absolute;right:0;top:0;background:none;border:0;color:#c59640;font-size:25px;cursor:pointer}.geo-figure{background:#fafdff;border:1px solid #edf2f6;border-radius:7px;margin:15px 0 18px}.geo-svg{display:block;width:100%;max-height:310px;height:auto;min-height:200px}.geo-svg text{text-anchor:middle;font-size:18px;fill:#41576b;stroke:none;font-family:"Microsoft YaHei",sans-serif}.geo-svg .geo-small{font-size:14px}.geo-top{fill:#d6edfc;stroke:#3e708d;stroke-width:2;stroke-linejoin:round}.geo-side{fill:#e8f3fb;stroke:#3e708d;stroke-width:2;stroke-linejoin:round}.geo-right{fill:#bfdff3;stroke:#3e708d;stroke-width:2}.geo-hidden{fill:none;stroke:#7b9db0;stroke-width:1.8;stroke-dasharray:6 5;stroke-linejoin:round}.geo-edge{fill:none;stroke:#3e708d;stroke-width:2}.geo-highlight-face,.geo-base{fill:#bdecd9}.geo-highlight-edge{stroke:#e18437;stroke-width:3}.geo-dot{fill:#e18437;stroke:white;stroke-width:1.5}.geo-net-face{cursor:pointer}.geo-net-face rect{fill:#e8f3fb;stroke:#4f819d;stroke-width:2}.geo-net-face.geo-net-selected rect{fill:#fde7bf;stroke:#d29431;stroke-width:3}.geo-arrow-line{fill:none;stroke:#dc7039;stroke-width:4}.geo-figure-tools{display:flex;justify-content:center;flex-wrap:wrap;gap:7px;margin:10px 0}.geo-figure-tools .button{font-size:12px;min-height:30px;padding:6px 12px}.geo-help{font-size:12px;color:#7f8c99;margin:15px 0;line-height:1.7}.geo-count-table{max-width:600px;width:100%;margin:14px auto 20px;border-collapse:collapse;text-align:center;font-size:14px}.geo-count-table th,.geo-count-table td{padding:10px;border:1px solid #dbe5ed}.geo-count-table th{background:#f0f7fc}.geo-options{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;border:0;padding:0;margin:18px 0}.geo-options label{display:flex;align-items:center;gap:10px;border:1px solid #d7e3ec;border-radius:6px;padding:13px 15px;cursor:pointer;font-size:15px;min-width:0}.geo-options label:has(input:checked){border-color:#3095d2;background:#eef8fe}.geo-options input{position:absolute;opacity:0;width:1px}.geo-options label>span{border:1px solid #bdd0dd;border-radius:50%;font-size:12px;display:grid;place-items:center;width:24px;height:24px;flex-shrink:0;color:#5e7b91}.geo-options label:focus-within{outline:2px solid #288dcb;outline-offset:2px}.geo-fill{display:flex;align-items:center;gap:20px;font-size:15px;margin:20px 0}.geo-fill input{width:180px;border:1px solid #b7cede;border-radius:5px;padding:12px;font-size:18px}.geo-submit-row{display:flex;gap:12px;justify-content:center;margin:20px 0 0}.geo-submit{min-width:190px}.geo-bottom-actions{display:flex;gap:10px;flex-wrap:wrap;justify-content:center;margin-top:17px}.geo-feedback{border-radius:7px;padding:20px 23px;margin-top:20px;border-left:4px solid #369767;background:#f2faf6}.geo-feedback.incorrect{border-color:#d88a3a;background:#fff8ef}.geo-feedback h2{font-size:18px;margin:0 0 9px}.geo-feedback p{font-size:14px;line-height:1.8;margin:6px 0}.geo-hint{padding:13px 18px;background:#fff8e7;border-radius:6px;margin-top:18px;font-size:14px}.geo-hint p{margin:8px 0 0}.geo-concept{font-size:17px;line-height:1.9;color:#455e72;margin:20px 0}.geo-example-steps{padding-left:24px;font-size:16px;line-height:1.9}.geo-example-steps li{margin-bottom:9px}.geo-coach-guide{margin-top:25px;border-top:1px dashed #d8e2eb;padding-top:15px;font-size:13px;color:#6b7c8c}.geo-coach-guide summary{cursor:pointer}.geo-coach-guide form{display:flex;gap:10px;flex-wrap:wrap}.geo-coach-guide input{padding:9px;border:1px solid #ccd9e4;border-radius:4px;width:min(390px,100%)}.geo-teacher-back{display:flex;justify-content:space-between;margin-top:20px}.geo-teacher-back .button{font-size:12px;min-height:30px;padding:6px 11px}.geo-complete{text-align:center;padding:35px 10px}.geo-complete-icon{width:75px;height:75px;background:#e3f5ee;color:#30976b;border-radius:50%;font-size:40px;display:grid;place-items:center;margin:0 auto 20px}.geo-complete h1{font-size:26px;margin:15px 0}.geo-complete p{max-width:580px;margin:15px auto 25px;line-height:1.8;color:#718190}.geo-complete .button{margin:7px}.geo-stats{display:grid;grid-template-columns:repeat(3,1fr);gap:15px;margin:23px 0}.geo-stats article{background:#f2f7fb;padding:22px 14px;text-align:center;border-radius:7px;font-size:13px;color:#718395}.geo-stats strong{display:block;color:#2987bf;font-size:30px;margin-bottom:8px}.geo-change-point{border-top:1px solid #e2e9f0;margin-top:25px;padding-top:20px}.geo-change-point h2{font-size:18px}.geo-change-point .button{margin:6px}.geo-report-row{padding:20px 0;border-bottom:1px solid #e4ebf1}.geo-report-row h2{font-size:20px}.geo-report-row h3{font-size:17px}.geo-page-heading{display:flex;justify-content:space-between;align-items:center;margin-bottom:20px}.geo-path{padding-left:25px;line-height:1.8;margin:30px 0}.geo-path li{padding-bottom:25px}.geo-path b{display:block}.geo-path span{font-size:15px;color:#657b8e}.geometry-app button:disabled{opacity:.5;cursor:not-allowed}.sr-only{position:absolute;width:1px;height:1px;padding:0;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
@media(max-width:900px){.geo-header{gap:12px;padding:12px 20px}.geo-header nav{order:3;width:100%;justify-content:center}.geo-role{margin-left:auto}.geo-topic-cards{gap:13px}.geo-topic-card>div:last-child{padding:15px}.geo-topic-card h2{font-size:18px}.geo-workspace{grid-template-columns:155px minmax(0,1fr);gap:15px}.geo-main{padding:22px 18px}.geo-paper{padding:20px}.geo-class-status span{margin:0 7px}.geo-class-status .button{padding:5px 8px}}
@media(max-width:600px){.geo-header{padding:10px 12px}.geo-brand{font-size:15px}.geo-brand span{font-size:22px}.geo-role{gap:0}.geo-role button{padding:5px;font-size:10px}.geo-header nav{gap:0;justify-content:space-between;overflow:auto}.geo-header nav button{padding:8px 5px;font-size:12px;white-space:nowrap}.geo-main{padding:18px 12px}.geo-home-title h1{font-size:29px}.geo-home-title p{font-size:14px;line-height:1.7}.geo-topic-cards{grid-template-columns:1fr;gap:16px}.geo-topic-card{display:grid;grid-template-columns:125px minmax(0,1fr)}.geo-topic-card>.geo-figure{height:auto;min-height:170px}.geo-topic-card>.geo-figure svg{min-height:130px}.geo-topic-card>div:last-child{padding:16px 13px}.geo-topic-card h2{font-size:19px;margin:3px 0 7px}.geo-topic-card p{font-size:12px;line-height:1.6;margin:7px 0 12px}.geo-topic-card .button{padding:7px;min-height:34px;font-size:13px}.geo-workspace{grid-template-columns:1fr;gap:12px}.geo-sidebar{padding:10px}.geo-sidebar>p,.geo-sidebar h2,.geo-sidebar>.button,.geo-center-link{display:none}.geo-sidebar nav{display:flex;gap:5px}.geo-sidebar nav button{flex:1;justify-content:center;font-size:12px;padding:10px 5px;gap:0;white-space:nowrap}.geo-sidebar nav span{display:none}.geo-class-status{padding:9px 10px;flex-wrap:wrap;gap:8px}.geo-class-status>div:last-child{margin-left:auto}.geo-paper{padding:18px 14px}.geo-paper-heading h1{font-size:19px;line-height:1.6}.geo-svg{min-height:150px;max-height:270px}.geo-options{grid-template-columns:1fr;gap:8px}.geo-options label{font-size:14px;padding:11px}.geo-fill{gap:12px}.geo-fill input{width:145px}.geometry-app .button{font-size:13px;padding:9px 14px}.geo-submit{min-width:145px}.geo-submit-row{gap:8px}.geo-concept{font-size:15px}.geo-stats{gap:6px}.geo-stats article{font-size:11px;padding:18px 5px}.geo-stats strong{font-size:25px}.geo-feedback{padding:15px}.geo-feedback h2{font-size:16px}.geo-footer{padding:12px;font-size:11px}.geo-count-table{font-size:12px}.geo-count-table td,.geo-count-table th{padding:8px 5px}.geo-coach-guide input{width:100%}}

@media(max-width:600px){.geo-figure-matching .geo-svg{max-height:none;min-height:0}}

@media(max-width:900px){.geo-header nav{flex:0 0 100%;width:100%;order:3}}

.active-classrooms{margin:0 0 26px;padding:20px;border:1px solid #aac8ef;border-radius:14px;background:#f1f7ff}.active-classrooms h2{font-size:20px;margin:0 0 8px}.active-classrooms>p{color:#40556f;font-size:14px}.active-classroom{display:flex;justify-content:space-between;gap:18px;padding:16px;background:white;border-radius:10px;margin-top:12px}.active-classroom p{margin:8px 0;font-size:14px}.active-classroom .actions{align-items:center;flex-wrap:wrap}.geo-class-status{position:sticky;top:0;z-index:5;background:#fff;border:1px solid #d6e2f1;border-radius:12px;padding:14px;box-shadow:0 3px 16px #183a6510}.geo-class-status>div:last-child{display:flex;gap:10px}.button[data-end-danger],.geo-button[data-end-danger]{background:#a52e35;color:#fff;border-color:#a52e35;min-height:44px;font-weight:700}.class-end-backdrop{position:fixed;inset:0;z-index:1000;background:#10264288;display:flex;align-items:center;justify-content:center;padding:20px;overflow:auto}.class-end-dialog{background:white;width:min(560px,100%);padding:26px;border-radius:16px;color:#24374d;max-height:90vh;overflow:auto;box-shadow:0 20px 80px #10264255}.class-end-dialog h2{font-size:24px;margin-top:0}.class-end-dialog dl{background:#f1f6fb;padding:16px;border-radius:10px}.class-end-dialog dl>div{display:flex;justify-content:space-between;gap:16px;padding:8px 0}.class-end-dialog dd{margin:0;font-weight:700}.class-end-dialog p{line-height:1.7}.class-end-policy{font-size:14px;color:#52647a}.class-end-dialog .actions{display:flex;flex-wrap:wrap;gap:12px}.classroom-complete{display:flex;justify-content:space-between;gap:16px;padding:18px;background:#eaf6ef;border-radius:12px;margin:16px 0}.classroom-complete h2{font-size:20px;margin:0 0 6px}.classroom-complete p{margin:0}@media(max-width:700px){.active-classroom,.classroom-complete{flex-direction:column}.geo-class-status{padding:12px;flex-wrap:wrap}.geo-class-status>div:last-child{width:100%;margin-top:8px}.class-end-dialog{padding:20px}.class-end-backdrop{padding:12px}}

.geo-section-title{font-size:23px;margin:34px 0 16px}.algebra-topic-cards{grid-template-columns:repeat(2,minmax(0,1fr))}.algebra-equation{padding:42px 24px;background:#f2f7fd;border:1px solid #e0eaf5;border-radius:14px;margin:22px 0;text-align:center}.algebra-equation>div{font-family:"Cambria Math","STIX Two Math",serif;font-size:38px;line-height:1.65;overflow-wrap:anywhere}.algebra-equation p{font-size:15px;color:#506985;margin:14px 0 0}.algebra-topic-cards .algebra-equation{border:0;margin:0;border-radius:0;padding:36px 20px;min-height:125px}.algebra-visual{background:#f2f7fd;border-radius:14px;padding:24px;margin:24px 0}.algebra-visual>p{text-align:center;color:#506985;font-size:15px}.algebra-table{margin:auto;width:min(470px,100%);border-collapse:collapse;font-size:25px}.algebra-table th,.algebra-table td{padding:16px;text-align:center;border-bottom:1px solid #c8d8ec}.algebra-table th{font-size:18px}.algebra-zero{color:#1c67bf;background:#dcecff;font-weight:700}.algebra-branch-root{font:34px "Cambria Math",serif;text-align:center;padding:12px}.algebra-branches{display:flex;align-items:center;justify-content:center;gap:30px;margin:28px 0}.algebra-branches>span{font:30px "Cambria Math",serif;border:2px solid #8bb5e5;border-radius:12px;padding:20px;background:white}.algebra-branches>b{font-size:24px;color:#2874cd}.algebra-contrast{display:grid;grid-template-columns:1fr 1fr;gap:20px}.algebra-contrast article{background:white;padding:20px;border-radius:12px}.algebra-contrast article>div{font:25px "Cambria Math",serif;margin:22px 0;overflow-wrap:anywhere}.algebra-work-label{display:flex;flex-direction:column;gap:12px;line-height:1.7;margin:22px 0;font-weight:600}.algebra-work-label textarea{font:17px/1.7 inherit;padding:14px;border:1px solid #b8cde6;border-radius:10px;resize:vertical;width:100%;box-sizing:border-box}.algebra-worked{padding:22px;border-left:4px solid #6c9dd9;background:#f2f7fd;line-height:1.8;white-space:pre-wrap}.algebra-repair-choice{padding:18px;border-radius:12px;background:#fff6e9;margin:16px 0}.algebra-repair-buttons{display:flex;flex-wrap:wrap;gap:8px}.algebra-review{padding:20px;margin:24px 0;border:1px solid #d8e3f1;border-radius:12px;line-height:1.8}.algebra-review summary{cursor:pointer;font-weight:700}.algebra-review article{padding:20px 0;border-bottom:1px solid #e5edf6}.algebra-review article p{white-space:pre-wrap;overflow-wrap:anywhere}.algebra-review button{margin-right:8px;margin-top:8px}.geo-feedback.pending{background:#f0f5ff;border-color:#92b7e8}@media(max-width:700px){.algebra-topic-cards,.algebra-contrast{grid-template-columns:1fr}.algebra-equation{padding:24px 12px}.algebra-equation>div{font-size:26px}.algebra-visual{padding:16px}.algebra-branches{gap:15px}.algebra-branches>span{font-size:24px;padding:15px}.algebra-contrast article>div{font-size:24px}.algebra-table th,.algebra-table td{padding:12px}.algebra-work-label textarea{font-size:16px}}

.algebra-work-label textarea{font-family:inherit;font-size:17px;font-weight:400;line-height:1.7}

.geo-book-image{margin:18px 0;padding:12px;border:1px solid #dedbd3;border-radius:12px;background:white}.geo-book-image img{display:block;max-width:100%;height:auto;margin:auto}.geo-book-image figcaption{margin-top:8px;font-size:13px;color:#65675d}.highschool-card-mark{padding:26px;background:#f4ead7;color:#6b512b;font-size:20px;font-weight:700}.geo-original-solution{margin:20px 0;line-height:1.8}.geo-original-solution li{white-space:pre-wrap}