:root{
  --accent:#2563eb; --accent-dark:#1d4ed8; --ok:#16a34a; --bg:#f8fafc;
  --card:#fff; --line:#e2e8f0; --ink:#0f172a; --muted:#64748b; --maxw:820px;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:system-ui,-apple-system,"Segoe UI","Hiragino Kaku Gothic ProN",Meiryo,sans-serif;
  margin:0;background:var(--bg);color:var(--ink);line-height:1.75;-webkit-font-smoothing:antialiased}
a{color:var(--accent)}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 16px}

/* header / footer */
.site-head{background:var(--card);border-bottom:1px solid var(--line)}
.site-head .wrap{display:flex;align-items:center;justify-content:space-between;height:56px}
.brand{font-weight:800;font-size:1.05rem;color:var(--ink);text-decoration:none}
.brand span{color:var(--accent)}
.nav a{margin-left:16px;font-size:.9rem;text-decoration:none;color:var(--muted)}
.nav a:hover{color:var(--accent)}
.site-foot{margin-top:56px;border-top:1px solid var(--line);background:var(--card)}
.site-foot .wrap{padding:24px 16px;font-size:.82rem;color:var(--muted)}
.site-foot a{color:var(--muted);margin-right:14px}

/* hero + tool */
h1{font-size:1.5rem;line-height:1.45;margin:24px 0 6px}
.h1-what{font-size:.85em}
.h1-val{color:var(--accent);font-size:1.12em}
.lead{color:var(--muted);margin-top:0}
.badges{display:flex;gap:8px;flex-wrap:wrap;margin:16px 0 24px}
.badge{display:inline-flex;align-items:center;gap:7px;background:var(--card);
  color:var(--ink);border:1px solid var(--line);border-radius:8px;
  font-size:.82rem;padding:7px 13px;font-weight:600}
.badge::before{content:"";width:14px;height:14px;flex:none;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 24 24' fill='none' stroke='%23059669' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6L9 17l-5-5'/%3E%3C/svg%3E") center/contain no-repeat}
#drop{border:2px dashed #93c5fd;border-radius:16px;padding:40px 20px;
  background:linear-gradient(180deg,#f5f9ff,#eaf2ff);
  text-align:center;cursor:pointer;transition:.18s}
#drop::before{content:"";display:block;width:46px;height:46px;margin:0 auto 14px;
  background:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='46' height='46' viewBox='0 0 24 24' fill='none' stroke='%232563eb' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Crect x='3' y='3' width='18' height='18' rx='2'/%3E%3Ccircle cx='8.5' cy='8.5' r='1.5'/%3E%3Cpath d='M21 15l-5-5L5 21'/%3E%3C/svg%3E") center/contain no-repeat}
#drop:hover,#drop.hover{border-color:var(--accent);background:linear-gradient(180deg,#eaf2ff,#dbe9ff);transform:translateY(-1px)}
#drop strong{color:var(--accent)}
.controls{display:flex;gap:18px;align-items:center;flex-wrap:wrap;margin:18px 0}
.controls label{font-size:.9rem;color:var(--muted)}
select{padding:4px 8px;border:1px solid var(--line);border-radius:6px}
#status{font-size:.9rem;color:var(--muted);min-height:1.4em;margin:8px 0}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:14px;margin-top:16px}
.item{background:var(--card);border:1px solid var(--line);border-radius:12px;overflow:hidden}
.item img{width:100%;height:120px;object-fit:cover;display:block;background:#f1f5f9}
.item .meta{padding:8px 10px;font-size:.78rem;color:var(--muted);word-break:break-all}
.item a.dl{display:block;text-align:center;padding:8px;background:var(--accent);color:#fff;
  text-decoration:none;font-size:.85rem;font-weight:600}
.item a.dl:hover{background:var(--accent-dark)}
.item .err{color:#dc2626;padding:8px 10px;font-size:.8rem}
.btn{padding:10px 18px;background:var(--ok);color:#fff;border:none;border-radius:8px;
  font-weight:600;cursor:pointer;font-size:.92rem}
.btn[hidden]{display:none}
.btn:disabled{opacity:.5;cursor:default}
#zipbtn{margin-top:16px}

/* article / content */
.content{padding:8px 0 8px}
.content h2{font-size:1.2rem;margin:32px 0 8px;padding-top:8px;border-top:1px solid var(--line)}
.content h2::before{content:"";display:inline-block;width:4px;height:.9em;background:var(--accent);
  border-radius:2px;margin-right:10px;vertical-align:-1px}
.content h3{font-size:1.03rem;margin:22px 0 6px}
.content p,.content li{font-size:.98rem}
.content ul,.content ol{padding-left:1.3em}
.content .cta{display:inline-block;margin:8px 0;padding:10px 18px;background:var(--accent);
  color:#fff;text-decoration:none;border-radius:8px;font-weight:600}
.content .note{background:#f1f5f9;border-left:4px solid var(--accent);padding:12px 16px;
  border-radius:6px;margin:16px 0;font-size:.92rem}
.steps{list-style:none;counter-reset:step;padding:0;margin:16px 0;
  display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:14px}
.steps li{counter-increment:step;background:var(--card);border:1px solid var(--line);
  border-radius:12px;padding:16px 16px 14px}
.steps li::before{content:counter(step);display:flex;align-items:center;justify-content:center;
  width:30px;height:30px;border-radius:50%;background:var(--accent);color:#fff;
  font-weight:700;font-size:.95rem;margin-bottom:10px}
.faq-item{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin:10px 0}
.faq-item h3{margin:0 0 6px;font-size:1rem;display:flex;gap:8px;align-items:flex-start}
.faq-item h3::before{content:"Q";flex:none;display:inline-flex;align-items:center;justify-content:center;
  width:22px;height:22px;border-radius:6px;background:#eff6ff;color:var(--accent);font-weight:800;font-size:.85rem}
.faq-item p{margin:0;color:var(--muted)}
.breadcrumb{font-size:.8rem;color:var(--muted);margin:16px 0 0}
.breadcrumb a{text-decoration:none}
.updated{font-size:.8rem;color:var(--muted);margin-top:4px}
.related{margin-top:12px}
.related a{display:block;padding:6px 0}

/* small utilities (kept out of inline style= so CSP style-src can stay strict) */
.mt24{margin-top:24px}
.drop-main{margin:0 0 6px}
.drop-sub{margin:0;font-size:.85rem;color:var(--muted)}
.foot-note{margin:.6em 0 0}