:root{--ink:#1f2d3d;--muted:#5b6b7f;--line:#dbe3ee;--paper:#f4f7fb;--card:#fff;--accent:#2563eb;--lesson:#17324d;--soft:#e8eef7;--gold:#d5a64b;--ok:#168b78;--wait:#b7791f}
body[data-lesson="2"]{--lesson:#172b4d;--accent:#e9826b;--soft:#fdeee9}
body[data-lesson="3"]{--lesson:#30343b;--accent:#c79a3b;--soft:#f6efe0}
body[data-lesson="4"]{--lesson:#211d3d;--accent:#7c6cf0;--soft:#ecebfd}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.75 'Pretendard','Malgun Gothic','Apple SD Gothic Neo',system-ui,sans-serif;word-break:keep-all;overflow-wrap:anywhere}
a{color:var(--accent)}
.wrap{max-width:1400px;margin:0 auto;padding:0 24px}
.site-header{background:var(--lesson);color:#fff}
.site-header-inner{max-width:1400px;margin:auto;display:flex;align-items:center;justify-content:space-between;gap:16px;padding:14px 24px}
.site-brand{color:#fff;text-decoration:none;font-weight:750;font-size:15px;line-height:1.4;display:flex;flex-direction:column}
.site-brand span{font-size:10.5px;color:#c6d2e2;font-weight:500}
.site-nav-links{display:flex;flex-wrap:wrap;gap:4px;justify-content:flex-end}
.site-nav-links a{color:#dfe7f1;text-decoration:none;font-size:13px;font-weight:600;padding:7px 11px;border-radius:8px;white-space:nowrap}
.site-nav-links a:hover{background:#ffffff18;color:#fff}
.site-nav-links a[aria-current="page"]{background:#ffffff24;color:#fff;box-shadow:inset 0 -2px #ffffffaa}
.site-nav-links .tag{font-size:10.5px;margin-left:5px;padding:1px 6px;border-radius:99px;background:#ffffff26;color:#fff;font-weight:600}
.lesson-pill{font-size:12px;padding:4px 10px;border-radius:99px;background:#ffffff22;color:#fff}
.hero{background:linear-gradient(125deg,var(--lesson),color-mix(in srgb,var(--lesson) 78%,#3a6d8f));color:#fff;padding:44px 0 40px}
.hero .eyebrow{font-size:12.5px;letter-spacing:.04em;color:#ffffffc4;margin:0}
.hero h1{font-size:clamp(28px,3.4vw,44px);line-height:1.3;margin:10px 0 12px;letter-spacing:-.03em}
.hero p.lead{font-size:17px;margin:0;color:#ffffffe0}
.facts{display:flex;flex-wrap:wrap;gap:8px;margin:18px 0 0}
.facts span{background:#ffffff1c;border:1px solid #ffffff2a;border-radius:99px;padding:5px 13px;font-size:13.5px}
.actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:22px}
.btn{display:inline-flex;align-items:center;gap:8px;background:#fff;color:var(--lesson);border-radius:10px;padding:10px 16px;font-weight:700;font-size:14.5px;text-decoration:none;border:0;cursor:pointer;font-family:inherit}
.btn small{font-weight:500;color:var(--muted);font-size:12px}
.btn.ghost{background:#ffffff14;color:#fff;border:1px solid #ffffff55}
.btn.ghost small{color:#ffffffb0}
.btn:hover{transform:translateY(-1px)}
.btn:focus-visible,.nav-btn:focus-visible,.toc a:focus-visible{outline:3px solid #9cc0ff;outline-offset:2px}
.status{display:inline-block;font-size:12px;font-weight:700;border-radius:99px;padding:2px 10px;vertical-align:middle}
.status.ready{background:#e3f4ef;color:var(--ok)}
.status.preparing{background:#fdf1dc;color:var(--wait)}
.section{padding-top:30px;padding-bottom:30px}
.section h2{font-size:22px;margin:0 0 14px;letter-spacing:-.02em}
.flowbox{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:6px 18px}
.flowbox summary{cursor:pointer;font-weight:700;padding:12px 0}
.flow-table{width:100%;border-collapse:collapse;font-size:14px;margin:4px 0 14px}
.flow-table th,.flow-table td{border-top:1px solid var(--line);padding:8px 10px;text-align:left;vertical-align:top}
.flow-table th{background:var(--soft);font-weight:700}
.viewer{display:grid;grid-template-columns:290px minmax(0,1fr);gap:22px;padding:26px 24px 50px;max-width:1400px;margin:0 auto}
.toc{position:sticky;top:12px;align-self:start;max-height:calc(100vh - 24px);overflow:auto;background:var(--card);border:1px solid var(--line);border-radius:16px;padding:12px}
.toc h2{font-size:15px;margin:2px 6px 8px}
.toc details{border-top:1px solid var(--line)}
.toc summary{cursor:pointer;font-size:13.5px;font-weight:700;padding:8px 6px;list-style-position:inside}
.toc summary small{color:var(--muted);font-weight:500}
.toc ol{list-style:none;margin:0 0 8px;padding:0}
.toc a{display:block;font-size:13px;line-height:1.45;padding:5px 8px;border-radius:7px;color:var(--ink);text-decoration:none}
.toc a b{color:var(--muted);font-weight:600;margin-right:6px;font-variant-numeric:tabular-nums}
.toc a:hover{background:var(--soft)}
.toc a.is-current{background:var(--lesson);color:#fff}
.toc a.is-current b{color:#ffffffb0}
.stage-bar{display:flex;align-items:center;gap:8px;flex-wrap:wrap;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:8px 10px;margin-bottom:14px;position:sticky;top:0;z-index:5}
.nav-btn{border:1px solid var(--line);background:#fff;color:var(--ink);border-radius:9px;padding:8px 14px;font:inherit;font-size:14px;font-weight:700;cursor:pointer}
.nav-btn:hover{background:var(--soft)}
.nav-btn[disabled]{opacity:.4;cursor:default}
.counter{font-weight:700;font-variant-numeric:tabular-nums;min-width:86px;text-align:center}
.stage-bar .spacer{flex:1}
.stage-bar input{border:1px solid var(--line);border-radius:9px;padding:8px 10px;font:inherit;font-size:14px;width:190px}
.slide{background:var(--card);border:1px solid var(--line);border-radius:18px;overflow:hidden;margin-bottom:18px;scroll-margin-top:70px}
.slide figure{margin:0;background:#0f172a;aspect-ratio:16/9}
.slide figure img{display:block;width:100%;height:auto;aspect-ratio:16/9}
.slide-info{padding:18px 22px 22px}
.slide-meta{display:flex;flex-wrap:wrap;gap:6px;font-size:12.5px;color:var(--muted);margin-bottom:6px}
.slide-meta span{background:var(--soft);border-radius:99px;padding:2px 10px}
.slide-info h2{font-size:22px;line-height:1.4;margin:4px 0 6px;letter-spacing:-.02em}
.slide-info p.sub{margin:0;color:#334155;font-size:16px}
.memo{margin-top:14px;background:#fffaf0;border:1px solid #f1dfb6;border-left:5px solid var(--gold);border-radius:12px;padding:12px 16px;font-size:15px}
.memo strong{display:block;font-size:13px;color:#8a6414;margin-bottom:4px}
.js .slide{display:none}
.js .slide.is-active{display:block}
.js.show-all .slide{display:block}
.downloads{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px}
.dl{display:block;background:var(--card);border:1px solid var(--line);border-radius:14px;padding:14px 16px;text-decoration:none;color:var(--ink)}
.dl b{display:block;font-size:15.5px}
.dl small{color:var(--muted);font-size:13px}
.dl:hover{border-color:var(--accent)}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:16px}
.lesson-card{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:20px 22px;display:flex;flex-direction:column;gap:6px;border-top:6px solid var(--c,#17324d)}
.lesson-card h3{margin:2px 0 0;font-size:19px;line-height:1.4}
.lesson-card p{margin:0;font-size:14.5px;color:#334155}
.lesson-card .when{color:var(--muted);font-size:13px}
.lesson-card .links{display:flex;flex-wrap:wrap;gap:8px;margin-top:auto;padding-top:10px}
.lesson-card .links a,.lesson-card .links button{font:inherit;font-size:13.5px;font-weight:700;border-radius:9px;padding:7px 12px;text-decoration:none;border:1px solid var(--line);background:#fff;color:var(--ink);cursor:pointer}
.lesson-card .links a.primary{background:var(--c,#17324d);color:#fff;border-color:transparent}
.lesson-card.is-preparing{opacity:.92}
.preparing-box{max-width:760px;margin:40px auto 60px;background:var(--card);border:1px solid var(--line);border-radius:20px;padding:34px 32px;text-align:center}
.preparing-box .big{width:64px;height:64px;margin:0 auto;border-radius:18px;background:var(--soft);display:grid;place-items:center}.preparing-box .big svg{width:34px;height:34px;fill:none;stroke:var(--lesson);stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.preparing-box h2{font-size:24px;margin:14px 0 8px}
.preparing-box p{color:#334155;margin:6px 0}
.copy-row{display:flex;gap:8px;align-items:center;flex-wrap:wrap;font-size:13.5px;background:var(--soft);border-radius:10px;padding:8px 12px;margin-top:6px}
.copy-row code{font-size:12.5px;word-break:break-all}
.note{font-size:13.5px;color:var(--muted)}
footer{border-top:1px solid var(--line);padding:22px 24px 34px;text-align:center;font-size:13px;color:var(--muted)}
@media(max-width:980px){.viewer{grid-template-columns:1fr;padding:18px 16px 40px}.toc{position:static;max-height:none;order:2}.stage{order:1}.stage-bar input{width:100%}}
@media(max-width:600px){.stage-bar{position:static}.counter{min-width:0}.wrap{padding:0 16px}.site-header-inner{flex-direction:column;align-items:flex-start;padding:12px 16px}.site-nav-links{flex-wrap:nowrap;overflow-x:auto;width:100%;justify-content:flex-start}.hero{padding:30px 0}.slide-info{padding:14px 16px 18px}.slide-info h2{font-size:19px}.preparing-box{margin:24px 16px;padding:26px 18px}}
@media print{.site-header,.toc,.stage-bar,.hero .actions,footer{display:none!important}.js .slide{display:block!important;break-inside:avoid}.viewer{display:block;padding:0}.hero{background:none;color:#000;padding:0 0 10px}.slide{border:0}}
.share-bar{padding-top:18px}
.share-bar .copy-row{background:var(--card);border:1px solid var(--line);color:var(--ink);padding:10px 14px;margin:0}
.share-bar .copy-row code{color:var(--ink);background:var(--soft);border-radius:6px;padding:2px 8px}
.share-bar .nav-btn{padding:5px 12px;font-size:13px}
.prompts{margin-top:14px;display:grid;gap:10px}
.prompt{border:1px solid #c9d8f2;border-left:5px solid var(--accent);border-radius:12px;background:#f7faff;padding:0 16px 12px}
.prompt summary{cursor:pointer;font-weight:700;padding:11px 0 6px;font-size:15px}
.prompt summary small{font-weight:500;color:var(--muted);margin-left:4px}
.p-guide{margin:2px 0 8px;font-size:14px;color:#475569}
.p-sec{position:relative;margin-top:8px}
.p-label{font-size:12.5px;font-weight:700;color:var(--accent);margin-bottom:3px}
.prompt pre{margin:0;white-space:pre-wrap;word-break:keep-all;overflow-wrap:anywhere;font:15px/1.75 'Pretendard','Malgun Gothic',system-ui,sans-serif;background:#fff;border:1px solid var(--line);border-radius:10px;padding:12px 70px 12px 14px;color:#1e293b}
.p-copy{position:absolute;right:8px;bottom:8px;padding:4px 10px;font-size:12.5px}
@media print{.prompt{break-inside:avoid}.p-copy{display:none}}
@media(max-width:600px){.prompt{padding:0 10px 10px}.prompt pre{padding:12px 12px 44px;font-size:14.5px}}
.slide-actions{margin:10px 0 0}
.practice-link{display:inline-flex;align-items:center;gap:6px;background:var(--lesson);color:#fff;text-decoration:none;font-weight:700;font-size:14px;border-radius:9px;padding:7px 14px}
.practice-link:hover{opacity:.9}
.show-start{background:var(--lesson);color:#fff;border-color:transparent}
.show-start:hover{background:var(--lesson);opacity:.9}
.show-hero{background:var(--gold);color:#1f2937}
/* 슬라이드 쇼 */
.show{display:none;position:fixed;inset:0;z-index:1000;background:#000;color:#fff;font-family:inherit}
body.showing{overflow:hidden}
body.showing .show{display:block}
.show-img{position:absolute;inset:0;width:100%;height:100%;object-fit:contain;user-select:none}
.show-hit{position:absolute;top:0;bottom:0;width:50%;cursor:pointer;z-index:1}
.show-hit.left{left:0;cursor:w-resize}.show-hit.right{right:0;cursor:e-resize}
.show-bar{position:absolute;left:50%;bottom:18px;transform:translateX(-50%);display:flex;align-items:center;gap:6px;background:rgba(15,23,42,.86);border:1px solid rgba(255,255,255,.15);border-radius:14px;padding:7px 9px;z-index:3;transition:opacity .25s;white-space:nowrap}
.show .sb{font:inherit;font-size:14px;font-weight:700;color:#fff;background:rgba(255,255,255,.12);border:0;border-radius:9px;padding:8px 12px;cursor:pointer;text-decoration:none;line-height:1.2}
.show .sb:hover{background:rgba(255,255,255,.24)}
.show .sb[hidden]{display:none}
.show .sb.prac{background:#168b78}.show .sb.prm{background:#2563eb}
.show .sb.dark{background:#e2e8f0;color:#1e293b}
.show .sc{font-variant-numeric:tabular-nums;font-weight:700;font-size:14px;min-width:70px;text-align:center}
.show-hint{position:absolute;right:16px;bottom:16px;display:flex;gap:6px;z-index:2;opacity:0;transition:opacity .25s;pointer-events:none}
.show-hint span{font-size:12px;font-weight:700;background:rgba(15,23,42,.55);border-radius:99px;padding:3px 10px;color:#fff}
.show.idle{cursor:none}.show.idle .show-hit{cursor:none}
.show.idle .show-bar{opacity:0;pointer-events:none}
.show.idle .show-hint{opacity:.75}
.show-sheet{position:absolute;left:0;right:0;bottom:0;max-height:60vh;overflow:auto;background:#fff;color:var(--ink);border-radius:18px 18px 0 0;box-shadow:0 -12px 40px rgba(0,0,0,.45);transform:translateY(105%);transition:transform .3s ease;z-index:4;padding:0 26px 26px}
.show.sheet-open .show-sheet{transform:none}
.sheet-head{position:sticky;top:0;background:#fff;display:flex;justify-content:space-between;align-items:center;padding:14px 0 10px;border-bottom:1px solid var(--line);margin-bottom:6px;z-index:1}
.sheet-head strong{font-size:16px}
.show-sheet .prompts{margin-top:8px;max-width:1100px;margin-left:auto;margin-right:auto}
.show-sheet .prompt pre{font-size:18px;line-height:1.75}
.show-sheet .p-guide{font-size:15px}
.show-sheet .p-copy{font-size:14px;padding:6px 14px}
.show.windowed .show-bar{opacity:1}
@media(max-width:700px){.show-bar{bottom:8px;gap:4px;padding:5px}.show .sb{padding:7px 9px;font-size:13px}.show .sb.wide{padding:7px 8px}.show-sheet{padding:0 12px 16px;max-height:70vh}.show-sheet .prompt pre{font-size:15px}}
@media print{.show,.show-start,.slide-actions{display:none!important}}
.keys{margin:8px 2px 0}
.practice-section{background:var(--card);border:1px solid var(--line);border-radius:16px;padding:24px;margin:18px 0;scroll-margin-top:20px}
.practice-title{margin-top:36px!important}
.practice-return-fixed{position:fixed;left:18px;bottom:18px;z-index:50;background:var(--lesson);color:white;padding:10px 18px;border-radius:999px;text-decoration:none;font-weight:700;box-shadow:0 6px 20px #0003}
.data-preview{border-top:1px solid var(--line);margin-top:12px;padding-top:8px}
.data-preview summary{cursor:pointer;font-size:14px;font-weight:700}
.data-preview pre{white-space:pre-wrap;font:13px/1.7 ui-monospace,Consolas,monospace;word-break:break-word;background:var(--paper);padding:12px;border-radius:8px}
.data-preview li{font-size:13px}
.guide-link{background:#725522}
.prompt-editor{display:block;width:100%;min-height:280px;resize:vertical;border:1px solid var(--line);border-radius:10px;padding:14px 14px 48px;font:16px/1.7 'Malgun Gothic',system-ui,sans-serif;color:var(--ink);background:white}
.show-sheet .prompt-editor{font-size:18px;min-height:340px}
.inline-examples{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:12px}
button.practice-link{border:0;font-family:inherit;cursor:pointer}
@media(max-width:600px){.prompt-editor,.show-sheet .prompt-editor{font-size:14px;min-height:260px}}
kbd{display:inline-block;font:12px/1.4 ui-monospace,Consolas,monospace;background:#fff;border:1px solid var(--line);border-bottom-width:2px;border-radius:5px;padding:0 6px;color:var(--ink)}