/* Approved concept 03: white ground, saturated cards, characters outside the tiles. */
#ch1{background:#fff;color:#202e37;padding-top:42px;overflow:hidden;}
#ch1 .chapter-map-label{display:none;}
#ch1 .chapter-map{border-bottom:1px solid #dbe4eb;padding-bottom:20px;}
#ch1 .hero{display:grid;grid-template-columns:1.25fr 1fr;gap:60px;align-items:center;padding:40px 0 17px;}
#ch1 .eyebrow{font-size:13px;color:#2f6bd8;font-weight:700;margin:0 0 16px;}
#ch1 .eyebrow span{font-size:10px;color:#647c8a;margin-left:12px;font-weight:500;}
#ch1 h2{font-size:42px;line-height:1.5;letter-spacing:.01em;margin:0;}
#ch1 .intro{font-size:14px;line-height:2;color:#526f80;margin:20px 0 0;}
#ch1 .survey{position:relative;padding:24px 28px;background:#eff0f2;border-radius:24px;isolation:isolate;}
#ch1 .sample{font-size:13px;line-height:1.9;margin:0;}
#ch1 .sample strong{font-size:17px;}
#ch1 .stat>strong{font-family:Arial,sans-serif;display:block;font-size:104px;line-height:1.1;font-weight:700;letter-spacing:-.065em;color:#6b56bd;}
#ch1 .stat>strong span{font-size:42px;letter-spacing:-.03em;}
#ch1 .stat-detail>b{font-size:15px;}
#ch1 .dots{display:flex;gap:6px;margin:12px 0;}
#ch1 .dots i{height:10px;width:10px;border-radius:50%;background:#d4cbe7;}
#ch1 .dots .on{background:#8367db;}
#ch1 .stat-detail p{font-size:12px;margin:0;line-height:1.7;}
#ch1 .stat-spark{position:absolute;right:-17px;top:-24px;font-size:69px;color:#c7ef54;line-height:1;transform:rotate(12deg);}
#ch1 blockquote{display:flex;align-items:center;justify-content:flex-start;gap:22px;background:transparent;padding:12px 0 17px;margin:14px 0 26px;border-bottom:1px solid #e5e8eb;}
#ch1 blockquote>span{font-size:33px;line-height:1;color:#ff772d;}
#ch1 blockquote p{font-size:23px;line-height:1.5;font-weight:700;letter-spacing:.03em;margin:0;}
#ch1 .lesson-head{display:flex;justify-content:space-between;align-items:center;gap:30px;}
#ch1 .lesson-head .eyebrow{font-size:11px;margin-bottom:6px;color:#577385;}
#ch1 .lesson-head h3{font-size:23px;line-height:1.5;margin:0;}
#ch1 .lesson-head>p{max-width:39em;font-size:12px;line-height:1.95;color:#546f7e;margin:0;}
#ch1 .narrow{display:none;}
#ch1 .episode-tabs{gap:22px;margin-top:64px;}
#ch1 .episode-tab{--ep-color:#ff7628;--ep-tint:#ff7628;border:2px solid transparent;border-radius:20px;min-height:198px;padding-top:66px;background:var(--ep-tint);color:#222f34;overflow:visible;}
#ch1 .episode-tab.ep2{--ep-color:#7956c5;--ep-tint:#7956c5;color:#fff;}
#ch1 .episode-tab.ep3{--ep-color:#c9f255;--ep-tint:#c9f255;}
#ch1 .episode-tab.ep4{--ep-color:#eff0f2;--ep-tint:#eff0f2;}
#ch1 .episode-tab[aria-selected=true]{background:var(--ep-tint);border-color:currentColor;box-shadow:0 5px 0 #1b354822;}
#ch1 .episode-tab.ep2[aria-selected=true]{border-color:#3d207b;}
#ch1 .ep-stage{position:absolute;top:-48px;right:14px;width:119px;height:119px;pointer-events:none;}
#ch1 .ep-stage img{width:119px;height:119px;top:0;filter:drop-shadow(0 8px 6px #15354619);}
#ch1 .ep-orbit{display:none;}
#ch1 .ep-tab-label{padding:0 17px 19px;}
#ch1 .ep-tab-label strong{font-size:21px;line-height:1.6;margin:7px 0;}
#ch1 .ep-companion{font-size:10px;color:inherit;margin:0;padding-right:22px;}
#ch1 .ep-tab-mark{position:absolute;bottom:14px;right:12px;display:flex;align-items:center;justify-content:center;width:27px;height:27px;border:1px solid currentColor;border-radius:50%;font-size:18px;}
#ch1 .episode-tab[aria-selected=true] .ep-tab-mark:after{font-size:18px;}
#ch1 .episode-panels{margin-top:25px;}
#ch1 .episode-panel{background:#f5f7fa;}
@media(max-width:760px){
 #ch1{padding-top:24px;}#ch1 .chapter-map{padding-bottom:14px;}
 #ch1 .hero{grid-template-columns:1fr;gap:28px;padding-top:28px;}#ch1 h2{font-size:29px;line-height:1.6;}
 #ch1 .eyebrow{font-size:12px;}#ch1 .eyebrow span{font-size:9px;margin-left:8px;}
 #ch1 .intro{font-size:13px;margin-top:16px;}#ch1 .wide{display:none;}#ch1 .narrow{display:block;}
 #ch1 .survey{padding:23px 25px;}#ch1 .sample strong{font-size:16px;}#ch1 .stat>strong{font-size:92px;}#ch1 .stat>strong span{font-size:38px;}
 #ch1 .stat-spark{right:-5px;font-size:60px;top:-23px;}#ch1 .stat-detail>b{font-size:14px;}
 #ch1 blockquote{gap:12px;margin:20px 0 25px;padding:12px 0 20px;}#ch1 blockquote p{font-size:18px;}
 #ch1 .lesson-head{display:block;}#ch1 .lesson-head h3{font-size:22px;}#ch1 .lesson-head>p{font-size:12px;margin-top:13px;}
 #ch1 .episode-tabs{gap:58px 15px;margin-top:55px;}#ch1 .episode-tab{padding-top:60px;min-height:182px;}
 #ch1 .ep-stage{width:104px;height:104px;right:5px;top:-43px;}#ch1 .ep-stage img{width:104px;height:104px;top:0;}
 #ch1 .ep-tab-label{padding:0 11px 17px;}#ch1 .ep-tab-label strong{font-size:17px;}#ch1 .ep-companion{font-size:9px;line-height:1.8;}
 #ch1 .ep-tab-mark{width:24px;height:24px;right:9px;bottom:11px;}
}
/* 助教頭像暫定版（Figma 2970:681，2026-10-14）：方形底圖裁成圓形頭像 */
#ch1 .ep-stage img{border-radius:50%;object-fit:cover;filter:none;box-shadow:0 8px 18px #15354622;border:3px solid #fff;box-sizing:border-box;}