:root{--ink:#322e27;--muted:#746951;--page:#f8f6f0;--paper:#fffefb;--line:#d8cfbd;--accent:#865a17;--accent-hover:#70480e;--soft:#f4ead4;--good:#246347;--bad:#a33229;font-family:-apple-system,BlinkMacSystemFont,'Pretendard','Segoe UI',sans-serif;color:var(--ink);background:var(--page);line-height:1.7;color-scheme:light;scrollbar-color:#b3a17b var(--page)}
*{box-sizing:border-box}body{margin:0;-webkit-font-smoothing:antialiased;word-break:keep-all;overflow-wrap:anywhere}button,input,select{font:inherit}button,a,input,select{touch-action:manipulation}button,a{-webkit-tap-highlight-color:transparent}button{min-height:44px;border:1px solid var(--line);background:var(--paper);color:var(--ink);border-radius:9px;padding:10px 16px;cursor:pointer;font-weight:600;transition:background .18s ease-out}button:hover{background:var(--soft)}button:disabled{cursor:default;opacity:.55}input,select{caret-color:var(--accent)}a{color:var(--accent);text-underline-offset:4px}a:hover{text-decoration-thickness:2px}:is(a,button,input,select,canvas,summary):focus-visible{outline:3px solid var(--accent);outline-offset:3px}::selection{background:#e8d5a9;color:#3e3321}h1,h2,h3,p{margin-top:0}h1,h2,h3{line-height:1.5;word-break:keep-all;overflow-wrap:anywhere;text-wrap:balance}h1{font-family:inherit;font-size:clamp(30px,3vw,40px);letter-spacing:-.025em;margin-bottom:16px}h2{font-size:22px;margin-bottom:14px}h3{font-size:18px}p{max-width:72ch;text-wrap:pretty}svg{width:20px;height:20px}.primary{background:var(--accent);color:#fff;border-color:transparent}.primary:hover{background:var(--accent-hover)}.dark{background:var(--paper);color:var(--ink);border-color:#b3a17b}.text-button{padding:9px 0;border:0;background:transparent;font-weight:500;color:var(--accent);text-align:left}.text-button:hover{background:transparent;color:var(--accent-hover);text-decoration:underline;text-underline-offset:4px}[hidden]{display:none!important}.small{font-size:13px;color:var(--muted)}.skip{position:fixed;left:16px;top:-70px;padding:12px;background:var(--paper);z-index:10}.skip:focus{top:12px}
.topbar{height:76px;border-bottom:1px solid var(--line);background:var(--paper);display:flex;align-items:center;justify-content:space-between;padding:0 max(24px,calc((100vw - 1160px)/2));gap:16px}.brand{display:flex;align-items:center;gap:13px;color:#3e3321;text-decoration:none;font-size:23px;letter-spacing:-.02em;white-space:nowrap}.brand-mark{width:31px;height:31px;flex:none}.topbar nav{display:flex;align-items:center;gap:9px;font-size:14px}.layout{max-width:1208px;margin:auto;padding:24px}.content{min-width:0}.intro{padding:0 0 10px}.intro h1{margin-bottom:10px}.intro p{font-size:17px;color:var(--muted);line-height:1.9;margin-bottom:0}
.era-rail{margin:8px 0 16px}.era-toolbar{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-bottom:12px}.era-toolbar h2{font-size:15px;margin:0}.era-toolbar span{font-size:13px;color:var(--muted)}.era-timeline{display:flex;overflow-x:auto;gap:0;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:10px 0;scrollbar-width:thin;scroll-padding:12px;overscroll-behavior-x:contain}.era-timeline button{position:relative;flex:1 0 135px;min-width:0;min-height:94px;text-align:left;border:1px solid transparent;border-radius:0;background:transparent;padding:18px 12px 9px;font-size:16px;font-weight:500;line-height:1.65}.era-timeline button::before{content:'';position:absolute;left:12px;top:7px;width:7px;height:7px;background:#a7946d;border-radius:50%}.era-timeline button small{display:block;font-size:13px;color:var(--muted);font-weight:400;line-height:1.6;margin-top:6px;max-width:18ch}.era-timeline button[aria-pressed=true]{background:var(--soft);color:var(--accent);border-color:var(--accent);font-weight:700}.era-timeline button[aria-pressed=true]::before{background:var(--accent)}.era-timeline button:hover{background:transparent;text-decoration:underline;text-underline-offset:4px}.era-timeline button[aria-pressed=true]:hover{background:var(--soft)}.timeline-note{font-size:13px;color:var(--muted);line-height:1.6;margin:8px 0 0}
.learning-start{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:32px;align-items:start;margin:12px 0 18px}.era-introduction{padding:4px 0}.era-introduction h2{font-family:inherit;font-size:34px;letter-spacing:-.02em;margin-bottom:6px}.selected-period{color:var(--accent);font-size:15px;margin-bottom:14px}#eraDescription{font-size:18px;line-height:1.8;color:var(--muted);max-width:none;margin-bottom:16px}.era-context{border-top:1px solid var(--line);padding-top:14px;color:var(--muted);font-size:14px;line-height:1.9}.learning-path{display:flex;flex-wrap:wrap;gap:12px;list-style:none;padding:0;margin:18px 0 0;font-size:14px;color:var(--muted)}.learning-path li:not(:last-child)::after{content:'→';margin-left:12px;color:var(--accent)}.setup-panel{padding:20px;border:1px solid var(--line);border-radius:14px;background:var(--paper);min-width:0}.setup-finish{display:contents}.setup-panel h3{font-size:20px;margin-bottom:12px}.setup{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:10px 16px}.setup label{display:grid;gap:6px;color:var(--ink);font-size:14px;font-weight:600;min-width:0}.setup #startButton{grid-column:1/-1;min-height:50px;margin-top:7px}select{border:1px solid #b3a17b;background:var(--paper);color:var(--ink);border-radius:8px;min-height:46px;width:100%;padding:10px 24px 10px 10px;font-size:16px;font-weight:500;text-overflow:ellipsis}#guestButton{display:block;width:100%;text-align:center;font-size:16px;margin-top:8px}.shared-account-note{font-size:13px;color:var(--muted);text-align:center;line-height:1.8;margin:9px 0 0}.status{font-size:14px;color:var(--muted);min-height:25px;margin:14px 0 18px}.status.error{color:var(--bad)}.getting-started{padding:23px 0 0;border-top:1px solid var(--line);margin-top:25px}.getting-started h2{font-size:19px;margin-bottom:10px}.getting-started p{font-size:16px;color:var(--muted);line-height:1.9;max-width:70ch;margin-bottom:0}
#workspace{scroll-margin-top:20px}.study-bar{display:flex;align-items:center;justify-content:space-between;gap:18px;padding:14px 0;max-width:1000px;margin:auto}.study-bar h2{font-size:23px;margin-bottom:5px}.study-bar p{font-size:13px;color:var(--muted);margin:0}.study-actions{display:flex;gap:7px;align-items:center;flex-wrap:wrap}.study-actions button{font-size:14px;padding:8px 12px;min-height:44px}#saveState{font-size:13px;color:var(--muted);max-width:200px}.question-nav{display:flex;gap:7px;margin:16px auto 20px;flex-wrap:wrap;max-width:1000px}.question-nav button{width:44px;height:44px;padding:4px;font-size:14px;font-variant-numeric:tabular-nums}.question-nav button[aria-current=true]{border-color:var(--accent);color:var(--accent);background:var(--soft)}.question-nav button.has-result{height:62px;display:flex;flex-direction:column;justify-content:center;gap:0}.nav-result{font-size:12px;font-weight:600;line-height:1.5}.question-nav button.answered{background:#eeeae0}.question-nav button.correct{color:var(--good)}.question-nav button.incorrect{color:var(--bad)}.study-grid{display:grid;grid-template-columns:minmax(0,1fr);gap:24px;max-width:1000px;margin:auto}.study-grid.has-notes{grid-template-columns:minmax(0,1.4fr) minmax(260px,.9fr);max-width:none}#question{scroll-margin-top:20px;background:var(--paper);padding:32px;border:1px solid var(--line);border-radius:14px;min-width:0}.question-label{font-size:14px;color:var(--muted);margin-bottom:21px}.question-text{font-size:23px;font-weight:650;line-height:1.8;white-space:pre-line;margin-bottom:27px;max-width:50ch}.choices{border:0;margin:0;padding:0;display:grid;gap:12px}.choices label{display:flex;align-items:start;gap:13px;padding:14px 16px;border:1px solid #b3a17b;border-radius:9px;cursor:pointer;min-height:56px;font-size:16px;line-height:1.65}.choices input{margin-top:5px;accent-color:var(--accent);width:18px;height:18px;flex:none}.choices label:has(input:checked){background:var(--soft);border-color:var(--accent)}.choices label:has(input:disabled){cursor:default}.note{border:1px solid var(--line);border-radius:14px;align-self:start;background:var(--paper);overflow:hidden}.note-heading{padding:16px 17px 0;display:flex;justify-content:space-between;align-items:center;gap:10px}.note h3{font-size:15px;margin:0}.note-heading button{font-size:12px;min-height:36px;padding:4px 8px;background:transparent}.note>p{font-size:12px;color:var(--muted);margin:7px 17px 14px}.note canvas{display:block;width:100%;height:300px;background:#fff;color:var(--ink);touch-action:none;cursor:crosshair;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.note .note-hint{font-size:12px;margin-top:10px}.study-bottom{display:flex;justify-content:space-between;align-items:center;gap:10px;margin:24px auto;max-width:1000px}.study-bottom p{font-size:13px;color:var(--muted);margin:0}.feedback{margin-top:27px;border-top:1px solid var(--line);padding-top:23px}.feedback h3{color:var(--good);font-size:18px}.feedback.wrong h3{color:var(--bad)}.feedback p{font-size:16px;line-height:1.9}.feedback details{font-size:14px;margin:19px 0}.feedback summary{cursor:pointer;min-height:36px}.feedback li{margin:12px 0}.sources{display:flex;flex-direction:column;gap:10px;margin-top:19px;font-size:14px;overflow-wrap:anywhere}.summary{padding:25px 0;border-top:1px solid var(--line);max-width:1000px;margin:auto}.summary p{color:var(--muted);font-size:15px}.summary button{margin:6px 8px 0 0}
footer{margin-top:35px;border-top:1px solid var(--line);padding-top:23px;color:var(--muted);font-size:13px;display:flex;flex-wrap:wrap;align-items:center;gap:0 22px}footer p{flex-basis:100%;margin-bottom:8px}footer a{min-height:44px;display:inline-flex;align-items:center}footer button{font-size:14px}dialog{border:1px solid var(--line);border-radius:14px;width:min(560px,calc(100% - 32px));max-height:85vh;padding:28px;color:var(--ink);background:var(--paper);overflow:auto}dialog::backdrop{background:#302b2270}.dialog-heading{display:flex;align-items:start;justify-content:space-between;gap:16px}.dialog-heading h2{font-size:22px}.dialog-heading button{padding:8px 10px;min-height:44px;font-size:14px}dialog p{font-size:15px;line-height:1.9}dialog label{display:grid;gap:7px;font-size:14px;margin:18px 0}dialog input{width:100%;min-height:48px;border:1px solid #b3a17b;border-radius:8px;padding:10px;font-size:16px;background:var(--paper);color:var(--ink)}dialog form>.primary{width:100%;margin:8px 0}.parent-link{display:block;text-align:center;margin:20px 0 10px}.shelf-item{display:flex;justify-content:space-between;align-items:center;gap:12px;padding:18px 0;border-top:1px solid var(--line)}.shelf-item strong{display:block;font-size:15px}.shelf-item p{font-size:13px;color:var(--muted);margin:3px 0 0}.shelf-item button{flex:none;font-size:13px}#shelfMessage{color:var(--bad)}.print-only{display:none}
@media(max-width:1000px){.learning-start{gap:24px}.setup-panel{padding:25px}.study-grid.has-notes{grid-template-columns:1fr}.note canvas{height:260px}.study-bar{align-items:start;flex-direction:column}.study-actions{width:100%}}
@media(max-width:900px){.learning-start{grid-template-columns:1fr;gap:0}.era-introduction{display:contents}.era-introduction>#selectedEraTitle{order:0;margin:0}.era-introduction>.selected-period{order:1;margin:4px 0 16px}.setup-panel{order:2}.era-introduction>#eraDescription{order:3;margin:20px 0 12px}.era-introduction>.era-context{order:4;margin:0}.learning-path{display:none}.era-introduction>#empty{order:5;margin-top:20px}.era-introduction>#empty h2{font-size:20px}.setup-panel{padding:24px}}
@media(max-width:700px){.topbar{height:auto;min-height:70px;padding:12px 20px;gap:10px;flex-wrap:wrap}.brand{font-size:19px;gap:10px}.brand-mark{width:25px;height:25px}.topbar nav{margin-left:auto;gap:6px;font-size:14px;max-width:100%}.topbar nav button{font-size:14px;padding:8px 10px;min-height:44px}.layout{padding:20px}.intro{padding:0 0 12px}.intro h1{font-size:30px;margin-bottom:8px}.intro p{font-size:16px;line-height:1.7}.era-rail{margin:5px 0 16px}.era-toolbar{gap:10px;margin-bottom:8px}.era-toolbar h2{font-size:14px}.era-toolbar span{font-size:13px;max-width:none;text-align:right}.era-timeline{margin:0 -20px;padding:8px}.era-timeline button{flex-basis:140px;min-height:86px}.timeline-note{margin-top:8px}.learning-start{margin-top:16px}.era-introduction h2{font-size:28px}.selected-period{font-size:14px}#eraDescription{font-size:17px;line-height:1.8}.era-context{font-size:14px;padding-top:12px}.setup-panel{padding:18px}.setup-panel h3{font-size:19px;margin-bottom:14px}.setup{grid-template-columns:minmax(0,1.35fr) minmax(0,1fr);gap:12px}.setup-finish{display:grid;grid-column:1/-1;grid-template-columns:112px minmax(0,1fr);gap:12px;align-items:end}.setup label{font-size:14px}.setup-level select{padding-left:8px;padding-right:8px}.setup>.setup-activity{grid-column:1/-1}.setup #startButton{grid-column:auto;align-self:end;font-size:16px;min-height:50px;margin-top:0}.shared-account-note{font-size:13px}.getting-started p{font-size:16px}.study-bar{padding:10px 0}.study-bar h2{font-size:21px}.study-actions{gap:8px}.study-actions #saveState{flex-basis:100%;max-width:none}.question-nav{margin-top:14px;gap:8px}#question{padding:24px 20px}.question-label{font-size:14px;margin-bottom:19px}.question-text{font-size:21px;line-height:1.85;margin-bottom:25px}.choices label{font-size:16px;padding:14px 13px;gap:12px}.study-bottom button{font-size:14px;padding:10px 12px}.study-bottom p{font-size:14px}.note canvas{height:250px}.feedback p{font-size:16px}.feedback details{font-size:14px}dialog{padding:23px}.dialog-heading h2{font-size:20px}.shelf-item{align-items:start}.shelf-item button{padding:9px;font-size:14px}footer{gap:0 18px}}
@media(max-width:360px){.setup{grid-template-columns:minmax(0,1fr)}.setup-finish{display:contents}.setup #startButton{grid-column:1/-1}.setup:has(#passageChoice:not([hidden])) #startButton{grid-column:1/-1}.study-bottom{flex-wrap:wrap}.study-bottom p{order:3;flex-basis:100%;text-align:center}}

.setup>.setup-description,.setup>#passageChoice{grid-column:1/-1}.setup:has(#passageChoice:not([hidden]))>.setup-activity{grid-column:1/-1}.setup:has(#passageChoice:not([hidden])) #startButton{grid-column:auto;align-self:end}.setup-description{font-size:14px;color:var(--muted);line-height:1.8;margin:0}.setup-panel>#selectionHint{margin-top:10px}.reading-passage{margin-bottom:28px;padding-bottom:24px;border-bottom:1px solid var(--line)}.reading-passage h3{font-size:21px;margin-bottom:12px}.reading-passage p{font-size:17px;line-height:1.95;max-width:65ch}.reading-passage .passage-notice{font-size:14px};color:var(--muted);margin-bottom:20px}.reading-passage p:last-child{margin-bottom:0}
@media(max-width:700px){.reading-passage p{font-size:16px}.reading-passage h3{font-size:20px}.reading-passage .passage-notice{font-size:14px}}
@media print{.print-passage{break-after:page;font-size:12pt;line-height:2}.print-passage h2{font-size:16pt}.print-question>p{font-size:9pt;margin-bottom:2mm}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}
@media print{@page{size:A4;margin:14mm}body{background:white;color:black}.no-print,.layout,dialog{display:none!important}.print-only{display:block}#printSheet h1{font-size:20px;margin:0 0 8mm}.print-page{break-after:page;display:grid;grid-template-columns:1fr 1fr;grid-template-rows:116mm 116mm;grid-auto-flow:column;gap:5mm 10mm}.print-page:last-child{break-after:auto}.print-question{break-inside:avoid;border-bottom:1px solid #aaa;font-size:11pt;padding:0 0 5mm}.print-question h2{font-size:12pt}.print-question ol{padding-left:6mm;line-height:1.7}.print-solutions{break-before:page}.print-solutions article{break-inside:avoid;font-size:10pt;border-bottom:1px solid #ccc;padding:4mm 0}.print-solutions h2{font-size:12pt}}