:root{color-scheme:light;--bg:#fff;--panel:#fff;--panel-dark:#f7f9fc;--line:#dce2eb;--muted:#586274;--text:#151922;--blue:#145ce6;font-family:system-ui,-apple-system,'Hiragino Sans','Yu Gothic',sans-serif;font-size:16px;font-synthesis:none}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text)}button,input,select{font:inherit}button,a,input,select{touch-action:manipulation;-webkit-tap-highlight-color:transparent}button{cursor:pointer;transition:background .15s,border-color .15s}button:disabled{cursor:default}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid var(--blue);outline-offset:4px}a{color:var(--blue)}h1,h2,h3{margin:0;font-weight:600;line-height:1.6}h1{font-size:28px;letter-spacing:-.03em}h2{font-size:21px}h3{font-size:18px}p{line-height:1.9;color:var(--muted);margin:10px 0 18px}small{font-size:13px}button{line-height:1.6}.shell{max-width:1100px;padding:28px 40px 40px;margin:auto}.app-header{display:flex;align-items:center;justify-content:space-between;margin-bottom:24px;gap:16px}.brand{display:flex;align-items:center;gap:11px;text-decoration:none;color:var(--text);font-size:18px;letter-spacing:1px}.brand b{color:var(--blue);font-weight:600}.logo{display:grid;place-items:center;width:38px;height:38px;border-radius:9px;background:var(--blue);color:#fff;font-size:27px}.icon-button{display:grid;place-items:center;width:40px;height:40px;border:1px solid var(--line);border-radius:50%;background:#fff;color:var(--muted);font-size:23px;flex-shrink:0}.sound-toggle.enabled{color:var(--blue);border-color:var(--blue)}.navigation{display:flex;gap:16px;border-bottom:1px solid var(--line);margin-bottom:32px}.navigation button{border:0;background:transparent;padding:15px 10px;color:var(--muted);font-size:14px;display:flex;gap:8px;align-items:center;position:relative;min-height:50px}.navigation button>span{font-size:19px}.navigation button.active{color:var(--blue)}.navigation button.active:after{content:'';position:absolute;bottom:-1px;left:10px;right:10px;height:2px;background:var(--blue)}main{min-height:65vh}.page-heading{margin:0 0 24px}.eyebrow,.mini-label{font-size:12px;color:var(--muted);font-weight:500}.eyebrow{color:var(--blue)}.home-grid{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(0,1fr);gap:24px}.daily-card{padding:28px;border:1px solid var(--line);border-radius:16px;background:var(--panel-dark)}.card-top{display:flex;justify-content:space-between;align-items:center;gap:12px}.daily-card h2{font-size:27px;margin:15px 0 8px}.daily-card>p{font-size:14px;margin-bottom:26px}.primary,.secondary,.small-primary{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:48px;border-radius:9px;font-weight:500;padding:12px 18px;text-decoration:none}.primary{width:100%;background:var(--blue);color:#fff;border:1px solid var(--blue)}.primary:hover,.small-primary:hover{background:#104cbe;border-color:#104cbe}.secondary{background:#fff;color:var(--text);border:1px solid var(--line)}.secondary:hover{background:#f2f6fd;border-color:#a8b8d2}.small-primary{background:var(--blue);color:#fff;border:1px solid var(--blue);font-size:14px;min-height:44px}.pill{border-radius:20px;background:#eaf1ff;color:#164db0;font-size:12px;padding:5px 10px}.lesson-duration{display:block;text-align:center;font-size:12px;color:var(--muted);margin-top:13px}.home-side{display:flex;flex-direction:column;gap:14px;min-width:0}.review-card,.resume,.pace-shortcut{display:flex;justify-content:space-between;align-items:center;gap:16px;border:1px solid var(--line);border-radius:12px;background:#fff;color:var(--text);width:100%;padding:20px;text-align:left;min-height:56px}.review-card b{font-size:17px;font-weight:500}.review-card small{display:block;color:var(--muted);margin-top:6px}.review-card>span:last-child,.resume>span:last-child,.pace-shortcut>span{color:var(--blue)}.resume{background:#f3f7ff}.resume b{display:block;font-size:15px;margin-top:6px;font-weight:500}.resume>span:first-child{font-size:12px;color:var(--muted)}.resume b{color:var(--text)}.pace-shortcut{font-size:14px;margin-top:auto}.welcome{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-top:18px}.welcome p{font-size:12px;margin:0}.text-button,.inline-button{background:none;border:0;padding:10px 3px;color:var(--blue);font-size:14px;min-height:44px}.text-button:hover,.inline-button:hover{text-decoration:underline}.text-button:disabled{color:var(--muted);text-decoration:none}.section-heading{display:flex;justify-content:space-between;align-items:center;margin:34px 0 16px}.section-heading h2{font-size:18px}.subject-grid{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:12px}.subject-card{display:flex;flex-direction:column;align-items:flex-start;text-align:left;border:1px solid var(--line);border-radius:12px;background:#fff;padding:19px 16px;color:var(--text);min-width:0}.subject-card:hover{border-color:var(--blue);background:#f7faff}.subject-icon{font-size:23px;color:var(--blue);margin-bottom:14px}.subject-card b{font-size:15px;font-weight:500}.subject-meta{width:100%;font-size:12px;color:var(--muted);margin-top:16px}.subject-meta>span{float:right}.subject-tabs{display:flex;flex-wrap:wrap;gap:8px;margin:20px 0 26px}.subject-tabs button{border:1px solid var(--line);border-radius:8px;background:#fff;color:var(--muted);padding:10px 18px;min-height:44px;font-size:14px}.subject-tabs button.selected{color:var(--blue);border-color:var(--blue);background:#edf3ff}.map-heading{display:flex;justify-content:space-between;gap:20px;align-items:center;margin-bottom:22px}.map-heading h2>span{font-size:13px;font-weight:400;color:var(--muted);margin-left:12px}.map-heading p{font-size:13px;margin:5px 0 0}.journey{display:grid;gap:14px}.journey-row{display:block}.journey-marker{display:none}.journey-content{border:1px solid var(--line);border-radius:12px;padding:21px 23px;min-width:0}.unit-meta{display:flex;justify-content:space-between;gap:10px;flex-wrap:wrap;font-size:12px;color:var(--muted);margin-bottom:9px}.progress-count{color:var(--muted);font-size:12px;white-space:nowrap;font-weight:400}.journey-content h3{font-size:18px}.unit-bottom{display:flex;justify-content:space-between;align-items:center;gap:14px;margin-top:18px}.unit-bottom>span{font-size:12px;color:var(--muted)}.challenge-link{display:flex;justify-content:space-between;width:100%;border:0;border-top:1px solid var(--line);background:none;color:var(--blue);padding:13px 0 0;margin-top:16px;font-size:13px;text-align:left}.scope-note{margin-top:25px;font-size:13px;color:var(--muted)}.scope-note summary{cursor:pointer;padding:12px 0}.scope-note p{font-size:13px}.quiet-note{font-size:12px;margin:20px 0;line-height:1.9;color:var(--muted)}.pace-guide{background:#f4f7fc;padding:12px 20px;border-radius:10px}.pace-guide p{font-size:14px;margin:0}.pace-batch{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-bottom:16px}.pace-batch>div{display:flex;gap:16px}.pace-batch .text-button{font-size:12px}.pace-list{border:1px solid var(--line);border-radius:12px;overflow:hidden}.pace-row{padding:17px 20px;display:flex;justify-content:space-between;align-items:center;gap:18px;border-bottom:1px solid var(--line)}.pace-row:last-child{border-bottom:0}.pace-row label{font-size:15px}.pace-row label small{display:block;margin-top:5px}.pace-row select{color:var(--text);background:#fff;border:1px solid #bdc8d8;border-radius:8px;padding:10px 12px;min-height:44px;font-size:14px}.save-status{font-size:12px;color:var(--muted);margin:17px 0}.pace-finish{max-width:420px}.source-details{margin-top:26px}.source-details summary{font-size:13px;color:var(--muted);cursor:pointer;padding:12px 0}.source-details p,.source-details a{font-size:13px}.review-summary{display:flex;gap:20px;align-items:center;border-bottom:1px solid var(--line);padding-bottom:20px;margin-bottom:20px}.review-icon{font-size:30px;color:var(--blue)}.review-summary strong{font-size:30px;font-weight:500}.review-summary small{font-size:14px}.review-summary p{font-size:13px;margin:0}.review-list{display:grid;gap:12px}.review-row{display:flex;align-items:center;gap:17px;padding:20px;border:1px solid var(--line);border-radius:12px;background:#fff;color:var(--text);text-align:left;width:100%}.review-row:hover{border-color:var(--blue)}.review-dot{font-size:21px;color:var(--blue)}.review-row>span:nth-child(2){flex:1;min-width:0}.review-row small{display:block;font-size:12px;color:var(--muted)}.review-row b{display:block;margin:7px 0;font-size:16px;font-weight:500}.review-row>span:nth-child(2)>span{display:block;font-size:14px;color:var(--muted);overflow-wrap:anywhere}.empty-state{padding:32px 20px;text-align:center;background:var(--panel-dark);border-radius:12px}.empty-state>span{display:none}.empty-state h2{font-size:18px}.empty-state p{font-size:14px}.record-grid{display:grid;grid-template-columns:1fr 1fr;gap:20px}.record-number{padding:24px;border:1px solid var(--line);border-radius:12px}.record-number>span{font-size:13px;color:var(--muted)}.record-number>strong{display:block;margin-top:14px;font-size:34px;font-weight:500;color:var(--text)}.record-number small{font-size:13px;margin-left:7px;color:var(--muted)}.record-subjects{display:grid;grid-template-columns:1fr 1fr;gap:25px 32px;margin:30px 0}.record-subjects>div{display:flex;align-items:center;gap:14px}.record-subjects b{font-size:14px;white-space:nowrap;font-weight:500}.record-subjects>div>span{font-size:12px;color:var(--muted);white-space:nowrap}.meter{flex:1;height:5px;border-radius:5px;background:#e8edf5;overflow:hidden}.meter i{display:block;height:100%;background:var(--blue)}.record-settings{border-top:1px solid var(--line);padding-top:25px}.record-settings h2{font-size:19px}.sound-setting{display:flex;justify-content:space-between;align-items:center;max-width:500px;margin:24px 0;font-size:14px}.sound-setting input{width:20px;height:20px;accent-color:var(--blue)}.tip{font-size:13px!important}.backup-actions{display:flex;gap:12px;margin-top:20px}.file-label{position:relative;cursor:pointer}.file-label input{position:absolute;inset:0;width:100%;height:100%;opacity:0;cursor:pointer}.file-label:focus-within{outline:3px solid var(--blue);outline-offset:4px}
.in-lesson .app-header{border-bottom:1px solid var(--line);padding-bottom:22px}.lesson-shell{max-width:740px;margin:0 auto}.lesson-top{display:flex;align-items:center;gap:18px}.lesson-top .icon-button{border:0}.lesson-progress{height:5px;border-radius:6px;background:#e8edf5;flex:1;overflow:hidden}.lesson-progress>span{display:block;height:100%;background:var(--blue)}.lesson-breadcrumb{display:flex;gap:9px;flex-wrap:wrap;font-size:12px;color:var(--muted);margin:16px 0 24px}.lesson-paper{background:#fff;border:1px solid var(--line);border-radius:14px;padding:32px;min-width:0}.lesson-paper h1{font-size:25px;margin:12px 0 22px;line-height:1.8}.concept{font-size:17px;color:var(--text);line-height:2}.worked-example{padding:18px 21px;border-left:3px solid var(--blue);background:#f4f7fc;margin:23px 0;border-radius:0 8px 8px 0}.worked-example p{font-size:16px;color:var(--text);line-height:2;margin-bottom:0}.question-top{display:flex;justify-content:space-between}.question-text{font-size:23px!important;line-height:1.9!important;overflow-wrap:anywhere}.answer-options{display:grid;gap:11px;margin:24px 0}.answer-option{display:flex;align-items:center;gap:15px;width:100%;min-height:60px;border:1px solid #c3ccd9;background:#fff;color:var(--text);border-radius:9px;padding:13px 17px;text-align:left;font-size:18px;overflow-wrap:anywhere}.answer-option:hover:not(:disabled){background:#f3f7ff;border-color:var(--blue)}.answer-letter{display:grid;place-items:center;width:27px;height:27px;flex-shrink:0;font-size:12px;color:var(--muted);border:1px solid var(--line);border-radius:5px}.answer-option.correct{border:2px solid var(--blue);background:#edf3ff;color:#0e4099}.answer-option.correct .answer-letter{background:var(--blue);border-color:var(--blue);color:#fff}.answer-option.incorrect{border:2px dashed #404957;background:#f1f3f6}.answer-option.muted{color:#687385;background:#fafbfd}.hint-area{margin:18px 0}.hint-area small{margin-left:10px;color:var(--muted)}.hint-area #hints p{display:flex;gap:14px;align-items:baseline;padding:14px 16px;background:#f4f7fc;border-radius:8px;font-size:15px}.hint-area #hints b{font-size:12px;color:var(--blue)}.answer-feedback{padding:17px 20px;background:#edf3ff;border-radius:9px;margin-top:22px}.answer-feedback h2{font-size:17px;color:#114cae}.answer-feedback p{margin:6px 0 0;font-size:14px}.answer-feedback.is-wrong{background:#f0f2f5}.answer-feedback.is-wrong h2{color:var(--text)}.solution{padding:24px 0 8px}.solution p{font-size:16px;color:var(--text);line-height:2.1;overflow-wrap:anywhere}.insight-tabs{display:grid;gap:10px;margin:10px 0 24px}.insight-tabs details{border:1px solid var(--line);border-radius:9px;overflow:hidden}.insight-tabs summary{cursor:pointer;padding:15px 18px;color:var(--blue);font-size:14px}.insight-tabs h3{font-size:16px;margin:3px 18px 9px}.insight-tabs details>p{font-size:16px;line-height:2;margin:0 18px 18px;color:var(--text)}.condition{border-top:1px solid var(--line);background:#f7f9fc;padding:16px 18px}.condition b{font-size:12px;color:var(--muted)}.condition p{font-size:14px;margin:6px 0 0;line-height:1.9}.after-answer{display:grid;gap:12px;margin-top:18px}.reference-basics{margin-top:24px;padding-top:10px;border-top:1px solid var(--line)}.reference-basics summary{font-size:13px;color:var(--muted);padding:12px 0;cursor:pointer}.reference-basics p{font-size:15px;line-height:2}.skip-bonus{display:block;margin:15px auto}.bonus-invitation,.summary-paper{text-align:center}.bonus-invitation>.secondary{width:100%;margin-top:12px}.bonus-invitation>p{margin-bottom:28px}.takeaway{text-align:left;background:#f4f7fc;border-radius:9px;padding:20px;margin:24px 0}.takeaway p{font-size:16px;line-height:2;color:var(--text);margin-bottom:0}.summary-paper>.text-button{margin-top:13px}.challenge-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px;margin:22px 0}.challenge-card{border:1px solid var(--line);border-radius:12px;padding:23px;min-width:0;display:flex;flex-direction:column;gap:15px}.challenge-card h2{font-size:17px;line-height:1.9;overflow-wrap:anywhere}.challenge-card .secondary{width:100%;margin-top:auto}.graph-discovery{border:1px solid var(--line);border-radius:9px;padding:0 18px;margin:22px 0;background:#fafcff}.graph-discovery summary{padding:16px 0;color:var(--blue);font-size:14px;cursor:pointer}.graph-discovery svg{display:block;width:100%;height:auto}.graph-discovery p{font-size:14px}.graph-discovery label{display:flex;justify-content:space-between;flex-wrap:wrap;gap:10px;font-size:14px;margin:15px 0}.graph-discovery output{color:var(--blue)}.graph-discovery input{width:100%;min-height:36px;accent-color:var(--blue)}.graph-caption{min-height:48px}.storage-notice{padding:16px;border:1px solid #596b88;background:#eef3fb;border-radius:8px;line-height:1.8;font-size:14px;margin-bottom:20px}.storage-notice[hidden],.navigation[hidden]{display:none}dialog{max-width:560px;width:calc(100% - 32px);border:1px solid var(--line);border-radius:14px;padding:30px;background:#fff;color:var(--text)}dialog::backdrop{background:#15233c66}dialog h2{font-size:22px}dialog .primary,dialog .secondary{width:100%;margin-top:12px}.dialog-close{display:block;margin-left:auto;background:none;border:0;font-size:27px;min-width:40px;min-height:40px;color:var(--muted)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.skip-link{position:absolute;top:-100px;left:12px;background:var(--blue);color:#fff;padding:12px;z-index:100}.skip-link:focus{top:12px}
@media(max-width:850px){.shell{padding:24px}.subject-grid{grid-template-columns:repeat(3,minmax(0,1fr))}.navigation{gap:5px}.navigation button{flex:1;justify-content:center;font-size:13px;padding:14px 6px}.home-grid{grid-template-columns:1.2fr 1fr;gap:18px}}
@media(max-width:680px){.shell{padding:20px 18px calc(100px + env(safe-area-inset-bottom))}.app-header{margin-bottom:25px}.brand{font-size:16px}.logo{width:35px;height:35px}.sound-toggle{width:35px;height:35px;font-size:20px}.navigation{position:fixed;bottom:0;left:0;right:0;z-index:10;background:#fffffffa;border-top:1px solid var(--line);border-bottom:0;margin:0;padding:7px 4px calc(7px + env(safe-area-inset-bottom));gap:0}.navigation button{flex-direction:column;gap:4px;font-size:11px;padding:7px 2px;min-height:53px}.navigation button.active:after{display:none}.navigation button.active{background:#edf3ff;border-radius:8px}.page-heading{margin-bottom:20px}.page-heading h1{font-size:24px}.home-grid{grid-template-columns:minmax(0,1fr);gap:15px}.daily-card{padding:23px;border-radius:13px}.daily-card h2{font-size:24px}.daily-card>p{font-size:13px;margin-bottom:22px}.primary{min-height:50px}.home-side{gap:12px}.review-card,.resume,.pace-shortcut{padding:17px 19px}.welcome{align-items:flex-start;gap:10px}.welcome p{flex:1;line-height:1.9}.welcome .text-button{white-space:nowrap;font-size:12px;padding-top:0}.section-heading{margin-top:28px}.subject-grid{gap:10px}.subject-card{padding:17px 13px}.subject-card b{font-size:14px}.subject-icon{font-size:22px;margin-bottom:10px}.subject-meta{font-size:12px;margin-top:14px}.subject-tabs{gap:7px;margin:20px 0}.subject-tabs button{flex:1;min-width:28%;padding:9px 12px}.map-heading{display:block}.map-heading h2{font-size:20px}.map-heading h2>span{font-size:12px}.map-heading p{font-size:12px}.map-heading>.text-button{padding-bottom:0}.journey-content{padding:19px}.unit-meta{font-size:11px}.progress-count{font-size:11px}.unit-bottom{flex-wrap:wrap;gap:10px}.unit-bottom>span{font-size:11px}.unit-bottom button{margin-left:auto}.pace-row{padding:15px 14px;gap:10px}.pace-row label{font-size:14px}.pace-row select{padding:10px 7px;font-size:13px;max-width:145px}.pace-batch{align-items:flex-start}.pace-batch>div{display:flex;flex-direction:column;gap:0;align-items:flex-end}.pace-batch .text-button{min-height:34px;padding:5px 0}.record-grid{gap:12px}.record-number{padding:19px}.record-number>strong{font-size:30px}.record-subjects{grid-template-columns:1fr;gap:20px}.backup-actions .secondary{flex:1;padding:12px 8px;font-size:13px}.in-lesson .shell{padding-bottom:35px}.in-lesson .app-header{margin-bottom:16px;padding-bottom:20px}.lesson-top{gap:10px}.lesson-top .icon-button{width:30px;height:33px}.lesson-breadcrumb{font-size:11px;margin:14px 0 20px}.lesson-paper{padding:23px 20px;border-radius:12px}.lesson-paper h1{font-size:23px}.concept{font-size:16px}.worked-example{padding:16px;margin:22px 0}.worked-example p{font-size:16px}.question-text{font-size:21px!important}.answer-option{font-size:17px;padding:13px 14px;gap:12px}.answer-letter{width:25px;height:25px}.hint-area #hints p{padding:13px;font-size:15px}.solution p{font-size:16px}.insight-tabs summary{padding:15px;font-size:14px}.insight-tabs details>p{margin:0 15px 16px;font-size:16px}.insight-tabs h3{margin:3px 15px 9px}.condition{padding:15px}.takeaway{padding:18px}.summary-paper h1,.bonus-invitation h1{font-size:22px}.challenge-list{grid-template-columns:1fr}.challenge-card{padding:20px}.review-row{gap:12px;padding:17px 14px}.review-row small{font-size:11px}.review-row>span:nth-child(2)>span{font-size:14px}.graph-discovery{padding:0 12px}dialog{padding:23px}}
@media(max-width:360px){.shell{padding-left:13px;padding-right:13px}.subject-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.lesson-paper{padding:21px 16px}.question-text{font-size:19px!important}.pace-row{flex-wrap:wrap}.pace-row select{margin-left:auto}.unit-meta{flex-direction:column;align-items:flex-start}.daily-card{padding:20px}.daily-card h2{font-size:22px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{transition:none!important;animation:none!important;scroll-behavior:auto!important}}

.app-connection:not([hidden]){display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 16px;margin-bottom:18px;background:#edf3ff;border-radius:9px;font-size:14px}.app-connection button{background:#fff;color:var(--blue);border:1px solid var(--line);border-radius:7px;padding:8px 14px;min-height:44px;white-space:nowrap}#unit-dialog ol{padding-left:24px;line-height:2.2}#unit-dialog h3{font-size:16px;margin-top:18px}@media(max-width:640px){.shell{padding-top:max(20px,env(safe-area-inset-top));padding-left:max(16px,env(safe-area-inset-left));padding-right:max(16px,env(safe-area-inset-right))}.pace-row select{font-size:16px;max-width:155px}.icon-button{min-width:44px;min-height:44px}.in-lesson .lesson-top .icon-button{min-width:44px;min-height:44px}}