:root{--green:#0f5a46;--green2:#16745c;--mint:#edf7f2;--ink:#17312a;--muted:#526b62;--line:#d8e5de;--bg:#f5f8f6;--blue:#1859ae;--red:#a13237;font-size:18px;color-scheme:light}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans KR",sans-serif;line-height:1.65}button,a{font:inherit}button{cursor:pointer;touch-action:manipulation}button:disabled{cursor:default}button,a{-webkit-tap-highlight-color:transparent}button:focus-visible,a:focus-visible,summary:focus-visible{outline:3px solid #e2a929;outline-offset:4px}a{color:var(--green)}.wrap{max-width:760px;margin:auto;padding:24px 18px 42px}header{margin:0 0 22px}.brand{font-size:.85rem;font-weight:850;letter-spacing:.12em;text-decoration:none}.heading{font-size:1.5rem;letter-spacing:-.04em;font-weight:850;margin-top:3px}h1,h2,h3,p{margin:0}h1{font-size:1.42rem;line-height:1.4;letter-spacing:-.035em}h2{font-size:1.2rem;line-height:1.45}h3{font-size:1.06rem}.muted,.meta,footer{color:var(--muted)}.meta{font-size:.89rem;line-height:1.6}.meta+p{margin-top:7px}.card{background:white;border:1px solid var(--line);border-radius:20px;padding:24px;margin-bottom:15px}.hero{background:var(--mint)}.hero p{margin-top:10px}.hint{font-size:1rem;line-height:1.7;margin-top:10px}.section-label{margin:24px 0 10px;font-size:1.1rem;font-weight:800}.grid{display:grid;gap:12px}.unit,.lesson-link{display:block;width:100%;text-align:left;border:1px solid var(--line);background:white;border-radius:16px;padding:19px 20px;text-decoration:none;color:var(--ink)}.unit strong{display:block;font-size:1.14rem}.unit span{display:block;margin-top:5px;color:var(--muted);font-size:.93rem}.unit:active,.lesson-link:active{background:var(--mint)}.back{display:inline-block;min-height:44px;margin-bottom:7px;text-decoration:none;font-weight:700}.progress{height:8px;overflow:hidden;background:#dce8e1;border-radius:20px;margin:13px 0}.progress>span{display:block;height:100%;background:var(--green2)}.button{display:block;min-height:58px;padding:13px 18px;border:1px solid var(--line);border-radius:13px;background:white;color:var(--green);text-align:center;text-decoration:none;font-weight:800;width:100%;line-height:1.55}.button.primary{background:var(--green);border-color:var(--green);color:white}.button:disabled{background:#e0e7e3;border-color:#e0e7e3;color:#697b72}.button+.button{margin-top:10px}.top-space{margin-top:20px}.lesson-link{display:flex;gap:13px;align-items:center;padding:15px 17px;margin-top:9px;font-size:1.02rem}.lesson-number{min-width:32px;color:var(--green);font-weight:850}.lesson-link .status{margin-left:auto;white-space:nowrap;font-size:.85rem;font-weight:700;color:var(--green)}.step-line{display:flex;justify-content:space-between;gap:12px;align-items:center;margin-bottom:16px;font-size:.92rem}.step-tag{background:var(--mint);color:var(--green);padding:4px 11px;border-radius:8px;font-weight:800}.question{font-size:1.24rem;line-height:1.8;font-weight:750;word-break:keep-all;overflow-wrap:anywhere;margin:12px 0 22px;white-space:pre-line}.oxrow{display:grid;grid-template-columns:1fr 1fr;gap:15px}.ox{min-height:119px;background:white;border:2px solid var(--line);border-radius:18px;font-size:3.3rem;font-weight:850}.ox[data-answer=O]{color:var(--blue);border-color:#a8c2e5}.ox[data-answer=X]{color:var(--red);border-color:#e6b4b4}.feedback{background:var(--mint);border-radius:14px;padding:20px;margin-top:20px;border-left:5px solid var(--green)}.feedback.incorrect{background:#fff6ed;border-color:#a75a1a}.feedback h2{margin-bottom:12px}.feedback p{font-size:1.06rem;line-height:1.9;word-break:keep-all;overflow-wrap:anywhere;white-space:pre-line}.answer-line{color:var(--green);font-size:1.14rem;font-weight:850;margin-bottom:10px}.choice-list{display:grid;gap:11px}.choice{display:flex;align-items:flex-start;gap:12px;width:100%;text-align:left;border:2px solid var(--line);background:white;border-radius:14px;color:var(--ink);padding:16px;font-size:1.05rem;line-height:1.8;word-break:keep-all;overflow-wrap:anywhere}.choice .choice-number{font-weight:800;flex-shrink:0;min-width:25px}.choice.selected{border-color:var(--blue);background:#f0f6ff}.choice.correct{border-color:var(--green);background:var(--mint)}.choice.wrong{border-color:var(--red);background:#fff2f1}.choice:disabled{opacity:1;color:var(--ink)}.answer-status{display:block;font-size:.86rem;font-weight:800;color:var(--muted)}.source{margin:15px 0 5px;font-size:.89rem;color:var(--muted)}.source a{overflow-wrap:anywhere}.figure{width:100%;height:auto;display:block;max-width:680px;margin:18px auto;border:1px solid var(--line);border-radius:8px}.caption{text-align:center;margin:-10px 0 17px;font-size:.88rem;color:var(--muted)}.notice{padding:15px;border-radius:12px;background:#fff1d9;margin-bottom:18px;font-size:.94rem}.results{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin:20px 0}.result-block{background:white;border:1px solid var(--line);padding:15px;border-radius:14px;text-align:center}.result-block strong{display:block;font-size:1.6rem;color:var(--green)}.result-block span{font-size:.94rem}.feedback-buttons{display:grid;gap:10px;margin:16px 0}.feedback-buttons .selected{border:2px solid var(--green);background:var(--mint)}.feedback-thanks{margin:10px 0;color:var(--green);font-weight:700}details{margin-top:20px}summary{cursor:pointer;min-height:48px;font-weight:750;color:var(--green)}footer{font-size:.85rem;text-align:center;margin-top:25px}.source-extra{font-size:.88rem;overflow-wrap:anywhere}.quiet{margin-top:15px;font-size:.94rem}.support-note{margin-top:16px;background:#fff5df;border-radius:12px;padding:16px;font-size:.95rem;white-space:pre-line}.subunit-head{margin-top:5px}.bar-label{display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;font-size:.94rem}.storage-unavailable{color:var(--red)}
.question-block{margin:12px 0 24px}
.question-block>.question{margin:0}
.question-context{margin-top:16px;padding:18px 20px;border:1px solid var(--line);border-radius:13px;background:#f5f8f6;font-size:1.1rem;line-height:1.85;font-weight:500;word-break:keep-all;overflow-wrap:anywhere}
.question-context ul{margin:0;padding-left:1.25em;list-style-type:disc}
.question-context li{padding-left:.2em;white-space:pre-line}
.question-context li+li{margin-top:12px}
.question-context li::marker{color:var(--green)}
.ox-result{--result-color:var(--green);--result-bg:var(--mint);border:2px solid var(--result-color);border-radius:16px;overflow:hidden;margin:20px 0 0;scroll-margin-top:16px}
.ox-result.is-incorrect{--result-color:#9e3337;--result-bg:#fff2f1}
.ox-result-heading{display:flex;gap:12px;align-items:center;background:var(--result-color);color:white;padding:18px 20px}
.ox-result-heading h2{font-size:1.5rem;font-weight:850;line-height:1.4;margin:0}
.ox-result-icon{display:flex;align-items:center;justify-content:center;flex:0 0 38px;height:38px;border:2px solid currentColor;border-radius:50%;font-size:1.4rem;font-weight:850;line-height:1}
.ox-answer-pair{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);background:white}
.ox-answer-cell{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;min-width:0;padding:18px 10px;gap:5px}
.ox-answer-cell+.ox-answer-cell{border-left:1px solid var(--line)}
.ox-answer-cell.actual-answer{background:var(--result-bg)}
.ox-answer-label{font-size:1rem;font-weight:750;color:var(--ink)}
.actual-answer .ox-answer-label{font-weight:850}
.ox-answer-symbol{font-family:Arial,sans-serif;font-size:2.5rem;line-height:1.25;font-weight:850;color:var(--ink)}
.actual-answer .ox-answer-symbol{font-size:3rem}
.ox-answer-meaning{font-size:.93rem;color:var(--muted);word-break:keep-all}
.ox-explanation{background:#f5f8f6;border-left:0;border:1px solid var(--line);margin-top:16px}
@media(max-width:420px){.wrap{padding:18px 13px 32px}.card{padding:19px 17px}.heading{font-size:1.35rem}.question{font-size:1.17rem}.choice{padding:13px 11px;font-size:1.02rem}.unit{padding:17px}.feedback{padding:17px 14px}.step-line{font-size:.87rem}.results{gap:9px}.result-block{padding:12px 8px}.question-context{padding:16px 14px;font-size:1.06rem}.ox-result-heading{padding:15px 14px}.ox-result-heading h2{font-size:1.4rem}.ox-answer-cell{padding:15px 7px}.ox-answer-label{font-size:.94rem}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}

.context-steps{list-style:none;margin:0;padding:0}.context-steps li{display:flex;gap:.6em;padding:0}.context-marker{flex-shrink:0;font-weight:750}.context-steps li>span:last-child{min-width:0}.context-dialogue p,.context-case{white-space:pre-line}.context-dialogue p+p{margin-top:14px}.context-dialogue strong{font-weight:750}

/* Clear reading and progressive explanations, 2026-09-16. */
:root{--green:#086452;--green2:#0a7861;--mint:#eaf6f0;--ink:#182c38;--muted:#53646e;--line:#d2dee2;--bg:#f1f5f7;--blue:#235bad;--red:#a42c3a;font-size:20px}
:root[data-text-size=large]{font-size:23px}
body{font-family:system-ui,-apple-system,BlinkMacSystemFont,"Noto Sans CJK KR","Noto Sans KR","Malgun Gothic",sans-serif;line-height:1.75}
.wrap{max-width:790px;padding:22px 18px 40px}
.site-header{display:flex;align-items:center;justify-content:space-between;gap:14px;margin-bottom:22px}
.heading{display:flex;align-items:center;gap:10px;font-size:1.15rem;font-weight:800;letter-spacing:-.04em;line-height:1.35}
.header-mark{display:flex;align-items:center;justify-content:center;background:var(--green);color:white;width:43px;height:43px;border-radius:12px;font:700 23px Arial,sans-serif;gap:1px;flex-shrink:0}
.header-mark>span{font-size:26px}
.text-size{background:white;color:var(--ink);border:1px solid #acbdc5;border-radius:10px;min-height:45px;padding:8px 12px;font-size:18px;font-weight:750;white-space:nowrap}
.text-size[aria-pressed=true]{background:var(--ink);color:white;border-color:var(--ink)}
.card{border:1px solid #d4dfe4;border-radius:22px;padding:28px;box-shadow:0 3px 14px #17312a06}
.hero{background:#fff;border-top:5px solid var(--green)}
h1{font-size:1.38rem;line-height:1.5;color:var(--ink);letter-spacing:-.045em}
h2{font-size:1.15rem;line-height:1.55;letter-spacing:-.03em}
.hero p{color:var(--muted)}
.unit{position:relative;padding:22px 48px 22px 22px;border-color:#c8d6dd;box-shadow:0 2px 8px #17312a03}
.unit::after{content:'›';position:absolute;right:20px;top:23px;color:var(--green);font-size:1.4rem;font-weight:700}
.unit strong{font-size:1.15rem;line-height:1.55}
.unit span,.meta,.source,.caption,footer{font-size:18px}
.lesson-link{font-size:1rem;min-height:76px;padding:17px 20px;border-color:#c8d6dd}
.lesson-number{display:grid;place-items:center;background:#eaf1f4;color:#334e5c;border-radius:9px;min-width:36px;height:36px}
.lesson-link .status{background:var(--mint);color:var(--green);padding:3px 8px;border-radius:6px;font-size:18px}
.back{font-size:19px;margin-bottom:12px;line-height:1.6;display:flex;align-items:center}
.step-line{font-size:18px;margin-bottom:16px;gap:8px}
.step-tag{padding:6px 10px;border-radius:7px;font-size:18px;background:#e8f4ee;color:#075445}
.question-count{font-weight:800;white-space:nowrap}.question-count>span{font-weight:500;color:var(--muted)}
.learning-steps{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));list-style:none;padding:0;margin:0 0 26px;gap:6px}
.learning-steps li{display:flex;align-items:center;justify-content:center;gap:7px;color:#64747b;font-size:18px;padding:8px 1px;border-bottom:3px solid #e2e9ed;white-space:nowrap}
.learning-steps .active{color:var(--green);border-bottom-color:var(--green);font-weight:800}
.learning-steps .passed{color:#486757;border-bottom-color:#afd3bf}
.step-dot{display:grid;place-items:center;width:25px;height:25px;border-radius:50%;background:#e7edf0;font-size:16px;font-weight:750;flex-shrink:0}
.active .step-dot{color:white;background:var(--green)}.passed .step-dot{background:#e4f3e9;color:#126346}
.quiz-card h1{margin-bottom:22px}
.question{font-size:1.15rem;line-height:1.8;font-weight:750;letter-spacing:-.025em;margin:0 0 26px;word-break:keep-all;overflow-wrap:anywhere}
.ox-question{padding:22px;background:#f1f5f8;border-radius:14px;border-left:4px solid #678392}
.oxrow{gap:14px}.ox{min-height:142px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:5px;line-height:1.1;box-shadow:0 3px 0 #e4eaf0}
.ox-letter{font-family:Arial,sans-serif;font-size:3.05rem}.ox-word{font-size:1.06rem;line-height:1.5}
.ox[data-answer=O]{border-color:#809fcf;background:#f4f8ff;color:#204f91}
.ox[data-answer=X]{border-color:#cf939b;background:#fff7f7;color:#a32d3b}
.ox:hover,.choice:hover:not(:disabled){filter:brightness(.985)}
.quiet{font-size:18px;line-height:1.75}
.question-context{font-size:1.03rem;background:#f0f4f7;border:1px solid #ccd9e1;border-left:4px solid #698a9d;padding:20px 22px;margin-top:18px;line-height:1.9}
.question-context li+li{margin-top:14px}
.choice-list{gap:13px}
.choice{font-size:1.03rem;line-height:1.65;padding:19px 18px;border:2px solid #c9d6df;min-height:70px;border-radius:13px;gap:13px}
.choice-number{display:grid;place-items:center;min-width:27px;color:#395663;line-height:1.6}
.choice>span:last-child{min-width:0}
.choice.selected{background:#e9f1ff;border-color:#285ca9;box-shadow:0 0 0 1px #285ca9}
.choice.correct{border:2px solid #0a7554;background:#e9f7ee}
.choice.wrong{border:2px solid #b23543;background:#fff0f0}
.answer-status{font-size:18px;margin-top:6px;color:var(--green);font-weight:800}
.choice.wrong .answer-status{color:var(--red)}
.selection-hint{font-size:18px;line-height:1.65;color:#465c6a;margin:20px 0 0}
.button{min-height:64px;border-radius:12px;padding:16px 20px;font-size:1.05rem;font-weight:800}
.button.primary{background:var(--green);border-color:var(--green);box-shadow:0 3px 0 #044f41}
.button.primary:disabled{background:#dce4e9;color:#566775;border-color:#dce4e9;box-shadow:none}
.button.primary>span{margin-left:8px}
.ox-result{margin-top:22px;border-radius:16px;border-width:2px;scroll-margin-top:16px}
.ox-result-heading h2{font-size:1.4rem;line-height:1.5}
.ox-answer-label,.ox-answer-meaning{font-size:18px}
.feedback p{font-size:1.02rem;line-height:1.9}.ox-explanation{background:#f4f7f9}
.mc-result{padding:24px;border-radius:17px;margin-top:28px;background:#e9f7ee;border:2px solid #0a7554;color:#07553d;scroll-margin-top:16px}
.mc-result.is-incorrect{background:#fff0f0;border-color:#b23543;color:#8f2432}
.mc-result-title{display:flex;align-items:center;gap:12px;margin-bottom:7px}
.mc-result-title h2{font-size:1.5rem;color:inherit;margin:0;font-weight:850}
.result-mark{display:grid;place-items:center;width:38px;height:38px;border-radius:50%;background:#0a7554;color:white;font:700 27px Arial,sans-serif;flex-shrink:0}
.is-incorrect .result-mark{background:#a42c3a}
.result-answer{font-size:1.16rem;color:var(--ink)}.result-answer strong{font-size:1.3rem}
.result-selection{font-size:18px;margin-top:7px;color:#48565d}.result-selection>span{margin:0 7px}
.reason-card{padding:25px 0 23px;border-bottom:1px solid var(--line)}
.reason-label{display:inline-block;color:var(--green);font-size:18px;font-weight:800;background:var(--mint);padding:4px 10px;border-radius:6px;margin-bottom:12px}
.reason-card h2{font-size:1.12rem;margin:0 0 13px;word-break:keep-all;overflow-wrap:anywhere}
.reason-card p,.option-reason p{font-size:1rem;line-height:1.95;word-break:keep-all;overflow-wrap:anywhere;white-space:pre-line}
.my-wrong .reason-label{background:#fff0f0;color:#912b38}
.key-point{padding:18px 20px;margin:22px 0;background:#f0f5f9;border-left:4px solid #446d87;border-radius:0 12px 12px 0}
.key-point strong{font-size:18px;color:#345975;display:block;margin-bottom:8px}.key-point p{font-size:1rem;line-height:1.8;word-break:keep-all;overflow-wrap:anywhere}
.option-details{border:2px solid #9fb7c6;border-radius:14px;overflow:hidden;margin:22px 0 0;background:white}
.option-details>summary{display:flex;align-items:center;justify-content:space-between;gap:12px;list-style:none;margin:0;padding:19px 18px;min-height:65px;color:#234b62;background:#eef5fa;font-size:1rem;font-weight:800;line-height:1.5}
.option-details>summary::-webkit-details-marker{display:none}.details-open{display:none}
.option-details[open] .details-open{display:inline}.option-details[open] .details-closed{display:none}
.summary-plus{font:500 28px Arial,sans-serif;flex-shrink:0}.summary-plus:before{content:'+'}.option-details[open] .summary-plus:before{content:'−'}
.option-details-body{padding:0 18px}
.option-reason{padding:24px 0;border-top:1px solid var(--line)}
.option-reason-head{display:flex;align-items:flex-start;gap:9px;font-size:1rem;line-height:1.7;word-break:keep-all;overflow-wrap:anywhere}
.option-no{flex-shrink:0;font-weight:750}.option-reason-head strong{font-weight:750;min-width:0}
.option-tags{display:flex;gap:7px;flex-wrap:wrap;margin:10px 0 12px}
.option-verdict,.selected-tag{font-size:18px;line-height:1.6;border-radius:5px;padding:1px 7px;background:#eef1f3;color:#53616a}
.option-correct .option-verdict{background:#e4f5ea;color:#086344;font-weight:800}
.selected-tag{background:#eaf0fc;color:#2a538c}
.ox-recap{padding:16px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.ox-recap>summary{font-size:18px;line-height:1.8;min-height:36px;color:#425c6a}
.ox-recap .feedback{margin-top:10px}.source{line-height:1.7}.progress{height:10px}
.feedback-buttons .button{font-weight:700}
@media(max-width:480px){
 :root{font-size:19px}:root[data-text-size=large]{font-size:22px}
 .wrap{padding:16px 12px 30px}.site-header{gap:8px;margin-bottom:18px}
 .heading{font-size:21px;gap:8px}.header-mark{width:36px;height:36px;border-radius:10px;font-size:21px}
 .header-mark>span{font-size:23px}.text-size{font-size:18px;padding:6px 9px;min-height:44px}
 .card{padding:23px 18px;border-radius:18px}h1{font-size:1.28rem}
 .learning-steps{margin-bottom:22px;gap:4px}.learning-steps li{gap:4px;font-size:18px}.step-dot{width:23px;height:23px}
 .question{font-size:1.12rem;line-height:1.85}.ox-question{padding:18px 16px}
 .question-context{padding:18px 15px;font-size:1.02rem;line-height:1.9}
 .choice{padding:16px 13px;font-size:1.04rem;gap:10px}.ox{min-height:133px}
 .mc-result{padding:21px 17px}.mc-result-title h2{font-size:1.43rem}
 .result-selection{font-size:18px}.result-selection>span{margin:0 4px}
 .key-point{padding:17px 16px}.option-details>summary{padding:18px 14px}
 .option-details-body{padding:0 14px}.reason-card p,.option-reason p{line-height:1.9}
 .button{padding:16px 13px;line-height:1.65}.unit{padding:19px 43px 19px 18px}
}
@media(max-width:355px){.wrap{padding-left:9px;padding-right:9px}.card{padding-left:15px;padding-right:15px}.header-mark{display:none}.heading{font-size:20px}.step-tag{font-size:18px;padding:5px 7px}.step-line{gap:5px}.question-count{font-size:18px}.learning-steps li{font-size:18px;gap:3px}}