:root{
  --ink:#14233f;--ink2:#263752;--paper:#f8f7f3;--card:#fff;--line:#bdc8d4;--grid:#cdd9e3;
  --soft:#edf2f6;--gold:#a88737;--red:#b8493f;--green:#2e7561;--muted:#6d7887;
  --safe-bottom:max(12px,env(safe-area-inset-bottom));
}
*{box-sizing:border-box}html,body{margin:0;min-height:100%;font-family:"Noto Sans JP","Yu Gothic",Meiryo,system-ui,sans-serif;color:var(--ink);background-color:#edf2f6}
body{background-image:linear-gradient(var(--grid) 1px,transparent 1px),linear-gradient(90deg,var(--grid) 1px,transparent 1px);background-size:46px 46px}
button,select,input{font:inherit}button{cursor:pointer}.app-shell{max-width:760px;margin:0 auto;min-height:100vh;padding-bottom:calc(82px + var(--safe-bottom));background:rgba(248,247,243,.92);box-shadow:0 0 0 1px rgba(20,35,63,.05)}
.topbar{display:flex;align-items:flex-end;justify-content:space-between;padding:22px 20px 16px;border-bottom:2px solid var(--ink);background:rgba(248,247,243,.96);position:sticky;top:0;z-index:20}.topbar h1{font-family:serif;margin:2px 0 0;font-size:29px;letter-spacing:.03em}.eyebrow,.kicker{font-size:10px;letter-spacing:.18em;color:var(--gold);font-weight:800;margin:0}.version{font-size:11px;color:var(--muted);border:1px solid var(--line);padding:5px 8px;background:#fff}
main{padding:18px 16px 28px}.view{display:none}.view.active{display:block}.hero-card,.panel,.question-card{background:var(--card);border:1px solid var(--line);box-shadow:0 2px 8px rgba(20,35,63,.05)}.hero-card{padding:22px;margin-bottom:14px}.hero-card h2,.page-title h2,.section-head h2{font-family:serif}.hero-card h2{font-size:25px;margin:6px 0 6px}.hero-card p:not(.kicker){color:var(--muted);line-height:1.7;margin:0 0 18px;font-size:14px}
.primary,.secondary,.danger{width:100%;border:1px solid var(--ink);padding:13px 14px;background:var(--ink);color:#fff;font-weight:700}.primary.big{padding:16px;font-size:17px}.secondary{background:#fff;color:var(--ink)}.danger{background:#fff;color:var(--red);border-color:var(--red)}button:disabled{opacity:.45;cursor:not-allowed}
.metric-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-bottom:14px}.metric-card{border:1px solid var(--line);background:#fff;text-align:left;padding:14px;color:var(--ink);min-height:96px}.metric-card strong{font-size:30px;line-height:1;display:inline-block;margin-top:13px}.metric-card>span:last-child{font-size:12px;margin-left:3px;color:var(--muted)}.metric-label{font-size:11px;display:block;color:var(--muted);line-height:1.4}.metric-card.static{cursor:default}
.panel{padding:18px;margin-bottom:14px}.section-head{display:flex;align-items:flex-end;justify-content:space-between;margin-bottom:14px}.section-head h2{font-size:21px;margin:4px 0 0}.count-pill{font-size:11px;background:var(--soft);border:1px solid var(--line);padding:6px 9px}.quick-grid{display:grid;gap:9px}.quick-btn{display:flex;gap:12px;align-items:center;border:1px solid var(--line);background:#fff;padding:14px;text-align:left;color:var(--ink)}.quick-icon{width:34px;height:34px;display:grid;place-items:center;background:var(--ink);color:#fff;font-size:18px}.quick-btn b,.quick-btn small{display:block}.quick-btn b{font-size:14px}.quick-btn small{color:var(--muted);font-size:11px;margin-top:3px}.course-list{display:grid;gap:10px}.course-item{border:1px solid var(--line);padding:14px;background:var(--soft)}.course-item .row{display:flex;justify-content:space-between;gap:12px;align-items:center}.course-item b{font-size:15px}.course-item small{color:var(--muted)}.course-units{margin-top:10px;padding-top:10px;border-top:1px dashed var(--line);font-size:12px;color:var(--muted)}
.page-title{padding:4px 2px 14px}.page-title h2{font-size:28px;margin:4px 0}.page-title>p:last-child{font-size:13px;color:var(--muted);margin:0;line-height:1.7}.field-label{display:block;font-size:11px;letter-spacing:.08em;color:var(--muted);margin:18px 0 8px}.field-label:first-child{margin-top:0}.chip-row{display:flex;gap:8px;flex-wrap:wrap}.chip{border:1px solid var(--line);background:#fff;padding:8px 11px;color:var(--ink);font-size:13px}.chip.selected{background:var(--ink);color:#fff;border-color:var(--ink)}.check-list{display:grid;gap:8px}.check-item{display:flex;align-items:center;justify-content:space-between;border:1px solid var(--line);padding:11px 12px;background:var(--soft)}.check-item label{display:flex;align-items:center;gap:9px;font-size:13px}.check-item input{width:18px;height:18px;accent-color:var(--ink)}.check-item small{color:var(--muted)}.segmented{display:grid;grid-auto-flow:column;grid-auto-columns:1fr}.segmented button{border:1px solid var(--line);background:#fff;color:var(--ink);padding:11px 8px;font-size:12px;margin-left:-1px}.segmented button:first-child{margin-left:0}.segmented button.selected{background:var(--ink);color:#fff;border-color:var(--ink);z-index:1}.two-col{display:grid;grid-template-columns:1fr 1fr;gap:10px}.two-col select{width:100%;padding:12px;border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:0}.filter-summary{margin:18px 0 10px;padding:11px 13px;background:var(--soft);border:1px solid var(--line);font-size:12px}.filter-summary b{font-size:16px;margin-right:4px}
.stats-list{display:grid;gap:10px}.stat-row{border:1px solid var(--line);padding:12px}.stat-row .row{display:flex;justify-content:space-between;gap:10px}.bar{height:7px;background:var(--soft);margin-top:10px}.bar span{display:block;height:100%;background:var(--ink);width:0}.review-summary{display:grid;gap:0;border:1px solid var(--line)}.review-summary>div{display:flex;justify-content:space-between;padding:12px 14px;border-bottom:1px solid var(--line)}.review-summary>div:last-child{border-bottom:0}.review-summary span{font-size:12px;color:var(--muted)}.body-copy{font-size:13px;color:var(--muted);line-height:1.8;margin:-3px 0 14px}.panel .secondary,.panel .danger{margin-top:9px}.danger-panel{border-color:#d8b0ac}.app-info{display:grid;gap:0}.app-info>div{display:flex;justify-content:space-between;padding:10px 0;border-bottom:1px solid var(--line);font-size:12px}.app-info>div:last-child{border-bottom:0}.app-info span{color:var(--muted)}
.quiz-view{padding-top:2px}.quiz-top{display:flex;gap:12px;align-items:center;margin-bottom:15px}.icon-btn{width:42px;height:42px;border:1px solid var(--line);background:#fff;color:var(--ink);font-size:24px}.quiz-progress-wrap{flex:1;display:flex;align-items:center;gap:10px}.quiz-progress{height:7px;background:#fff;border:1px solid var(--line);flex:1}.quiz-progress span{display:block;height:100%;background:var(--gold);width:0}.quiz-progress-wrap>div:last-child{font-size:11px;color:var(--muted);min-width:42px;text-align:right}.quiz-meta{font-size:10px;color:var(--muted);display:flex;align-items:center;gap:6px;flex-wrap:wrap;margin-bottom:9px}.source-badge{padding:4px 7px;border:1px solid var(--line);background:#fff}.question-card{padding:20px}.question-head{display:flex;justify-content:space-between;gap:10px;font-size:11px;color:var(--gold);margin-bottom:16px}.question-card h2{font-family:serif;font-size:23px;line-height:1.75;font-weight:500;margin:0 0 20px}.answer-area{display:grid;gap:10px}.answer-btn{border:1px solid var(--line);background:#fff;color:var(--ink);padding:16px;text-align:left;line-height:1.6;min-height:58px}.answer-btn.ox{text-align:center;font-size:38px;min-height:110px}.answer-area.ox-grid{grid-template-columns:1fr 1fr}.answer-btn.correct{border-color:var(--green);background:#edf7f3}.answer-btn.wrong{border-color:var(--red);background:#fbefee}.answer-btn:disabled{opacity:1}.feedback{margin:18px 0 14px;padding-top:16px;border-top:1px solid var(--line)}.feedback-result{font-weight:800;font-size:15px;margin-bottom:10px}.feedback-result.ok{color:var(--green)}.feedback-result.ng{color:var(--red)}.explanation{font-size:14px;line-height:1.9;color:var(--ink2)}.hidden{display:none!important}
.result-view{text-align:center;padding:35px 16px}.result-mark{color:var(--gold);letter-spacing:.2em;font-size:11px}.result-view h2{font-family:serif;font-size:28px}.score-circle{width:160px;height:160px;border:2px solid var(--ink);border-radius:50%;margin:25px auto 15px;display:flex;justify-content:center;align-items:baseline;padding-top:51px}.score-circle strong{font-size:48px}.score-circle span{font-size:16px;color:var(--muted)}.result-view>p{color:var(--muted)}.result-actions{display:grid;gap:10px;margin-top:25px}
.bottom-nav{position:fixed;bottom:0;left:50%;transform:translateX(-50%);width:min(760px,100%);height:calc(68px + var(--safe-bottom));padding-bottom:var(--safe-bottom);display:grid;grid-template-columns:repeat(4,1fr);background:#fff;border-top:1px solid var(--line);z-index:30}.bottom-nav button{border:0;background:#fff;color:var(--muted);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:2px}.bottom-nav button span{font-size:20px}.bottom-nav button small{font-size:10px}.bottom-nav button.active{color:var(--ink);box-shadow:inset 0 3px 0 var(--ink)}.toast{position:fixed;left:50%;bottom:calc(82px + var(--safe-bottom));transform:translate(-50%,14px);max-width:calc(100% - 32px);background:var(--ink);color:#fff;padding:11px 14px;font-size:12px;opacity:0;pointer-events:none;transition:.2s;z-index:60}.toast.show{opacity:1;transform:translate(-50%,0)}
@media(min-width:620px){main{padding:22px}.metric-grid{grid-template-columns:repeat(4,1fr)}.quick-grid{grid-template-columns:1fr 1fr}.question-card{padding:28px}.stats-grid{grid-template-columns:repeat(4,1fr)}}

/* v1.3 source filters */
#sourceSeg{grid-auto-flow:row;grid-template-columns:repeat(2,minmax(0,1fr));gap:0}#sourceSeg button{margin-left:0;margin-top:-1px}
@media(min-width:620px){#sourceSeg{grid-template-columns:repeat(5,minmax(0,1fr))}}