:root{--bg:#f8f9ff;--paper:#fffefa;--ink:#1f2340;--muted:#5a5f7d;--accent:#5b6bd0;--line:#dce0ee;--warm:#e9d8c7;font-family:'Noto Sans JP','Hiragino Kaku Gothic ProN','Yu Gothic',sans-serif;color:var(--ink);background:var(--bg);line-height:1.85}*{box-sizing:border-box}body{margin:0;background:radial-gradient(ellipse at 100% 0,#f0e4dc88,transparent 50%);min-height:100vh}a{color:var(--accent);text-underline-offset:4px}button,input,textarea,select{font:inherit}button,a,input,textarea,select{touch-action:manipulation}button{cursor:pointer}.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-width:44px;min-height:44px;padding:11px 20px;border:1px solid var(--accent);border-radius:8px;background:var(--accent);color:white;text-decoration:none;line-height:1.5;cursor:pointer}.btn.secondary{background:transparent;color:var(--accent);border-color:var(--line)}.btn.danger{background:transparent;color:#9c4d59;border-color:#e6cbd0}.btn:disabled{opacity:.5;cursor:not-allowed}a:focus-visible,button:focus-visible,input:focus-visible,textarea:focus-visible,select:focus-visible{outline:3px solid #aab5ff;outline-offset:3px}header,main,footer{width:min(100% - 40px,960px);margin:auto}header{padding:24px 0;display:flex;align-items:center;justify-content:space-between;gap:12px}header a{min-height:44px;padding:10px 0;display:inline-flex;align-items:center;text-decoration:none;font-size:13px}.wordmark{letter-spacing:.18em;color:var(--muted)}main{padding:30px 0 60px;min-height:75vh}.eyebrow{font-size:11px;letter-spacing:.24em;color:var(--accent);text-transform:uppercase}h1,h2,h3,.serif{font-family:'Noto Serif JP','Yu Mincho','Hiragino Mincho ProN',serif;font-weight:500}h1{font-size:clamp(29px,5vw,46px);letter-spacing:.08em;line-height:1.5;margin:14px 0 20px}h2{font-size:24px;margin:0 0 16px}h3{font-size:20px}.intro{max-width:650px;color:var(--muted);margin-bottom:32px}.panel{background:var(--paper);border:1px solid var(--line);border-radius:12px;padding:clamp(20px,4vw,36px);margin:22px 0;box-shadow:0 8px 30px #33385a04}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,260px),1fr));gap:20px}.feature{display:block;margin:8px 0 28px;padding:clamp(28px,6vw,56px);border:1px solid var(--line);border-radius:16px;background:var(--paper);color:var(--ink);text-decoration:none;box-shadow:0 8px 30px #33385a08;transition:border-color .2s,box-shadow .2s}.feature:hover{border-color:var(--accent);box-shadow:0 12px 36px #5b6bd01a}.feature .number{font-size:12px;color:var(--accent);letter-spacing:.15em}.feature h2{font-size:clamp(26px,4.5vw,36px);margin:18px 0 16px}.feature p{color:var(--muted);max-width:620px;margin:0 0 24px}.feature .cta{display:inline-flex;align-items:center;gap:8px;min-height:44px;padding:11px 22px;border-radius:8px;background:var(--accent);color:#fff}.stack{display:grid;gap:18px}label{display:grid;gap:7px;font-size:14px}input:not([type=checkbox]),textarea,select{width:100%;padding:12px;border:1px solid #cbd0e0;border-radius:7px;background:#fff;color:var(--ink);min-height:48px}textarea{min-height:130px;resize:vertical}input[type=checkbox]{width:22px;height:22px;margin:0}.check{display:flex;align-items:center;gap:12px;min-height:44px}.row{display:flex;gap:12px;flex-wrap:wrap;align-items:center}.row>*{max-width:100%}.hint,small{font-size:12px;color:var(--muted)}.status{color:var(--accent);white-space:pre-wrap;overflow-wrap:anywhere;min-height:1.8em}.error{color:#a43d50}.output{margin-top:20px}.output textarea{min-height:90px;font-size:12px}.envelope{text-align:center;background:linear-gradient(150deg,#f8f4e8,#eeedf7);padding:50px 20px;border:1px solid #ddd7d1;border-radius:8px}.envelope .seal{font-size:40px;color:var(--accent);display:block;margin-bottom:12px}.letter{white-space:pre-wrap;overflow-wrap:anywhere;font-family:'Yu Mincho',serif;font-size:18px;line-height:2.2}footer{border-top:1px solid var(--line);padding:20px 0 30px;text-align:center}footer a{font-size:11px;color:var(--muted);padding:12px;min-height:44px;min-width:44px;display:inline-flex;align-items:center}[hidden]{display:none!important}details summary{padding:12px 0;cursor:pointer;min-height:44px}@media(max-width:550px){header,main,footer{width:calc(100% - 32px)}header{padding-left:4px;padding-right:4px;flex-wrap:wrap}header .hint{min-width:0;text-align:right;overflow-wrap:anywhere}main{padding-top:10px}.row .btn{flex-grow:1}}