/* Standalone design proposal; the shared handbook grid remains unchanged. */
:root{--lesson-ink:#253b32;--lesson-muted:#657068;--lesson-line:#dce1d8;--lesson-surface:#fafbf7;--lesson-green:#2e6754}
html{scroll-behavior:smooth;scroll-padding-top:142px}
.design-preview{background:#f4f2e9;color:#26332b}
.design-preview .top-nav{background:rgba(244,242,233,.96)}
.design-preview .hb-main{width:100%;padding-top:38px;padding-bottom:80px}
.design-preview .breadcrumb{font-size:12px;gap:10px;margin-bottom:28px;color:#667268}
.design-preview .breadcrumb .current{color:#536257;font-weight:500}
.design-preview .hb-side{padding-top:38px}
.design-preview .hb-toc{box-shadow:none;border:1px solid #e5e7df;border-radius:12px;background:rgba(255,255,255,.82)}
.lesson-hero{margin:0 0 26px}
.lesson-eyebrow{display:flex;align-items:center;gap:8px;font-size:12px;line-height:20px;color:#486557;font-weight:600;letter-spacing:.06em;margin-bottom:12px}
.eyebrow-dot{width:6px;height:6px;background:#4c7c65;border-radius:50%}
.lesson-hero h1{font-size:clamp(30px,3.4vw,44px);font-weight:650;letter-spacing:-.04em;line-height:1.25;color:#203c2f;margin:0 0 12px}
.lesson-hero>p{font-size:17px;line-height:1.7;color:#5a695e;margin:0 0 17px}
.lesson-meta{display:flex;flex-wrap:wrap;gap:9px 17px;font-size:12px;line-height:20px;color:#687269}
.lesson-meta span+span{position:relative;padding-left:16px}
.lesson-meta span+span:before{content:'';position:absolute;left:0;top:9px;width:3px;height:3px;background:#a5afa5;border-radius:50%}
.lesson-video{margin:0;border-radius:16px;background:#fff;overflow:hidden;border:1px solid #dce2d8;box-shadow:0 10px 28px rgba(49,63,46,.045)}
.lesson-video video{display:block;width:100%;height:auto;aspect-ratio:1672/941;background:#f5f2e7}
.lesson-video figcaption{display:flex;justify-content:space-between;align-items:center;gap:10px;padding:14px 20px;font-size:12px;line-height:20px;color:#657368;background:#fdfefa}
.lesson-video figcaption>span:first-child{color:#375844;font-weight:600;display:flex;gap:8px;align-items:center}
.video-dot{width:5px;height:5px;border-radius:50%;background:#51866a}
.prep-section{margin:42px 0 38px}
.section-intro{display:flex;justify-content:space-between;align-items:flex-end;gap:20px;margin-bottom:18px}
.section-eyebrow{display:block;font-size:11px;letter-spacing:.09em;color:#6a786c;margin-bottom:6px}
.section-intro h2{font-size:24px;line-height:1.4;letter-spacing:-.025em;margin:0;color:#283d2f;font-weight:600}
.section-intro p{font-size:13px;line-height:22px;color:#687269;margin:0 0 3px}
.material-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
.material-card{display:flex;gap:20px;align-items:center;min-width:0;padding:16px;background:rgba(255,255,255,.65);border:1px solid #e0e4d9;border-radius:13px}
.material-card img{width:112px;height:112px;object-fit:cover;border-radius:9px;flex:none}
.material-purpose{font-size:11px;line-height:18px;color:#728071;display:block;margin-bottom:4px}
.material-card h3{font-size:18px;font-weight:600;line-height:26px;color:#294032;margin:0 0 7px}
.material-card p{font-size:13px;line-height:21px;color:#657365;margin:0}
.chapter-nav{position:sticky;top:64px;z-index:30;display:flex;gap:0;background:rgba(244,242,233,.97);backdrop-filter:blur(12px);border-top:1px solid #d8dfd2;border-bottom:1px solid #d8dfd2;margin:0 0 42px;overflow:hidden}
.chapter-nav a{position:relative;display:flex;align-items:center;justify-content:center;flex:1;gap:9px;min-height:58px;font-size:13px;font-weight:500;color:#61715f;transition:color .18s,background .18s}
.chapter-nav a span{font:11px ui-monospace,SFMono-Regular,Menlo,monospace;color:#86927f}
.chapter-nav a:hover{color:#244f3b;background:#e9eee3}
.chapter-nav a.is-active{color:#264d37;font-weight:650}
.chapter-nav a.is-active:after{content:'';position:absolute;height:2px;background:#386346;bottom:0;left:18px;right:18px}
.lesson-chapter{margin-bottom:44px;padding-bottom:42px;border-bottom:1px solid #dce1d6;scroll-margin-top:6px}
.chapter-heading{display:flex;align-items:center;gap:16px;margin-bottom:18px}
.chapter-number{font:500 17px ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:-.05em;color:#42634b;border:1px solid #cedbc9;background:#eaf0e2;display:grid;place-items:center;width:48px;height:48px;flex:none;border-radius:14px}
.chapter-eyebrow{display:block;font-size:11px;color:#72806d;line-height:17px;margin-bottom:3px;letter-spacing:.05em}
.chapter-heading h2{font-size:28px;line-height:38px;letter-spacing:-.025em;font-weight:600;color:#233f2e;margin:0}
.chapter-description,.action-block>p{font-size:15px;line-height:26px;color:#5c695c;margin:0 0 18px;max-width:68ch}
.chapter-description strong{font-weight:600;color:#375a43}
.action-block{margin-top:30px}
.action-block+.action-block{margin-top:34px}
.action-block h3{display:flex;align-items:center;gap:9px;font-size:17px;font-weight:600;line-height:27px;color:#2b4332;margin:0 0 6px}
.action-dot{height:5px;width:5px;background:#688765;flex:none;border-radius:50%}
.demo-panel{margin:0;background:#fff;border:1px solid #dfe5d9;border-radius:13px;overflow:hidden}
.demo-panel-top{min-height:44px;padding:10px 17px;display:flex;align-items:center;justify-content:space-between;gap:14px;border-bottom:1px solid #e5e9e0;font-size:11px;line-height:20px;color:#74816e;background:#fdfefa}
.image-hint{display:flex;gap:5px;align-items:center;color:#697961;font-size:11px}
.image-hint svg{width:13px;height:13px}
.screen-button{display:block;width:100%;text-align:left;padding:0;background:#f8f9f4;color:inherit;cursor:zoom-in}
.screen-button:hover{background:#f0f4e9}
.screen-button:focus-visible{outline:3px solid #2e6754;outline-offset:-4px}
.screen-stage{width:100%;padding:24px;display:flex;justify-content:center;align-items:center}
.ip-shot-frame{position:relative;flex:none;width:min(100%,var(--natural-width));max-width:100%;border-radius:7px;background:#fff;box-shadow:0 0 0 1px #d8ded4,0 5px 15px rgba(46,62,40,.04)}
.ip-shot-frame img{width:100%;height:auto;display:block;border-radius:7px}
.ip-shot-shade{position:absolute;inset:0;z-index:1;width:100%;height:100%;pointer-events:none;border-radius:7px}
.ip-mark{position:absolute;z-index:2;box-sizing:border-box;border:2px solid #a6c678;border-radius:7px;box-shadow:0 0 0 2px #fff;pointer-events:none}
.ip-mark:before{content:attr(data-label);position:absolute;top:-27px;left:-2px;display:block;background:#f6fbea;color:#334f23;border:1px solid #a6c678;border-radius:4px;padding:3px 7px;font-size:11px;line-height:17px;white-space:nowrap;font-weight:600;box-shadow:0 2px 4px rgba(20,40,10,.05)}
.ip-mark[data-placement="below"]:before{top:calc(100% + 5px)}
.ip-mark-result{border-color:#8bba9b}
.ip-mark-result:before{color:#2d6040;background:#eff8ed;border-color:#8bba9b}
.completion-note{display:flex;gap:10px;align-items:center;margin:20px 0 0;font-size:13px;line-height:22px;color:#536e4c}
.completion-note>span{display:grid;place-items:center;width:20px;height:20px;border-radius:50%;background:#e2ebd8;font-size:12px;flex:none}
.lesson-finish{display:flex;align-items:center;gap:18px;background:#e7eedf;border:1px solid #d8e1cf;padding:26px;border-radius:14px}
.finish-icon{display:grid;place-items:center;flex:none;width:42px;height:42px;border:1px solid #bdcfb0;border-radius:50%;color:#42653a}
.finish-icon svg{width:22px;height:22px}
.lesson-finish h2{font-size:20px;line-height:29px;font-weight:600;color:#284932;margin:0 0 5px}
.lesson-finish p{font-size:13px;line-height:22px;color:#60735b;margin:0}
.lesson-finish a{margin-left:auto;display:flex;align-items:center;justify-content:center;min-height:44px;white-space:nowrap;font-size:13px;color:#2d5739;text-decoration:underline;text-underline-offset:5px}
.screen-dialog{padding:0;border:1px solid #c7d2bf;border-radius:16px;max-width:calc(100vw - 48px);max-height:calc(100dvh - 48px);width:1180px;margin:auto;background:#f7f9f1;box-shadow:0 30px 100px #10251e44;overflow:hidden}
.screen-dialog::backdrop{background:rgba(17,30,21,.72)}
.screen-dialog header{display:flex;align-items:center;justify-content:space-between;padding:12px 20px;border-bottom:1px solid #dbe2d3;background:#fbfcf8;gap:20px}
.screen-dialog h2{font-size:16px;font-weight:600;color:#2c4432;margin:0}
.dialog-close{display:grid;place-items:center;flex:none;width:44px;height:44px;border-radius:50%;color:#3b5740;background:#e9eee3}
.dialog-close:hover{background:#dce6d3}
.dialog-close svg{width:20px;height:20px}
.screen-dialog-body{max-height:calc(100dvh - 170px);overflow:auto;padding:34px;display:flex;align-items:flex-start}
.screen-dialog-body .ip-shot-frame{margin:auto;width:var(--natural-width);max-width:100%}
.dialog-hint{display:none;text-align:center;font-size:12px;color:#63735c;padding:10px}
.skip-link{position:fixed;left:20px;top:-80px;background:#244f37;color:#fff;padding:12px 18px;z-index:300;border-radius:6px}
.skip-link:focus{top:8px}
.chapter-nav a:focus-visible,.lesson-finish a:focus-visible,.dialog-close:focus-visible{outline:3px solid #2e6754;outline-offset:3px}
@media(max-width:1180px) and (min-width:901px){.material-grid{grid-template-columns:1fr}.material-card img{width:96px;height:96px}.material-card p br{display:none}}
@media(max-width:900px){.design-preview .hb-side{padding-top:16px}.design-preview .hb-main{padding-top:26px}.lesson-hero h1{font-size:36px}.chapter-nav{top:64px}.screen-stage{padding:20px}.section-intro p{font-size:12px}}
@media(max-width:600px){.design-preview .breadcrumb{margin-bottom:22px;font-size:11px}.lesson-hero h1{font-size:32px}.lesson-hero>p{font-size:16px;line-height:27px}.lesson-meta{font-size:11px;gap:5px 10px}.lesson-meta span+span{padding-left:11px}.lesson-video{border-radius:12px}.lesson-video figcaption{padding:11px 13px;font-size:11px}.lesson-video figcaption>span:last-child{display:none}.prep-section{margin:30px 0}.section-intro{display:block;margin-bottom:14px}.section-intro h2{font-size:23px}.section-intro p{margin-top:6px;font-size:13px}.material-grid{grid-template-columns:1fr;gap:10px}.material-card{padding:12px;gap:18px}.material-card img{width:100px;height:100px}.material-card p br{display:none}.material-card h3{font-size:18px;margin-bottom:4px}.material-card p{font-size:14px;line-height:22px}.chapter-nav{margin-bottom:30px}.chapter-nav a{font-size:12px;gap:5px;min-height:52px}.chapter-nav a span{font-size:10px}.chapter-nav a.is-active:after{left:6px;right:6px}.chapter-heading{gap:12px}.chapter-number{width:40px;height:40px;border-radius:12px;font-size:15px}.chapter-heading h2{font-size:25px;line-height:34px}.chapter-description,.action-block>p{font-size:16px;line-height:27px}.action-block h3{font-size:17px}.screen-stage{padding:15px 10px}.demo-panel-top{padding:9px 11px;font-size:10px}.image-hint{font-size:10px}.ip-mark{border-width:1.5px;border-radius:4px;box-shadow:0 0 0 1px #fff}.ip-mark:before{font-size:9px;line-height:13px;padding:1px 4px;top:-19px;left:-1.5px}.ip-mark[data-placement="below"]:before{top:calc(100% + 2px)}.completion-note{align-items:flex-start;font-size:14px;line-height:23px}.lesson-chapter{margin-bottom:32px;padding-bottom:30px;scroll-margin-top:0}.lesson-finish{padding:20px;align-items:flex-start;gap:12px;flex-wrap:wrap}.lesson-finish h2{font-size:18px;line-height:27px}.lesson-finish p{font-size:14px;line-height:23px}.lesson-finish>div{flex:1;min-width:0}.finish-icon{width:32px;height:32px}.lesson-finish a{margin-left:44px}.screen-dialog{max-width:100vw;max-height:100dvh;width:100vw;height:100dvh;border:0;border-radius:0}.screen-dialog header{padding:10px 15px}.screen-dialog h2{font-size:16px}.screen-dialog-body{display:block;max-height:calc(100dvh - 122px);padding:32px 20px}.screen-dialog-body .ip-shot-frame{width:var(--natural-width);max-width:none;margin:0}.screen-dialog-body .ip-mark{border-width:2px}.screen-dialog-body .ip-mark:before{font-size:12px;line-height:18px;padding:3px 7px;top:-28px}.screen-dialog-body .ip-mark[data-placement="below"]:before{top:calc(100% + 4px)}.dialog-hint{display:block}.screen-dialog-body{height:calc(100dvh - 122px)}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}