:root { color-scheme: light dark; --bg: #f5f6f8; --fg: #111827; --panel: #ffffff; --muted: #6b7280; --accent: #1f2937; --danger: #b91c1c; --line: #e5e7eb; }
@media (prefers-color-scheme: dark) { :root { --bg: #0f1115; --fg: #f3f4f6; --panel: #1a1d24; --muted: #9ca3af; --accent: #e5e7eb; --line: #2b2f38; } }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg); font: 16px/1.5 -apple-system, "Hiragino Sans", "Noto Sans JP", sans-serif; padding: env(safe-area-inset-top) 0 env(safe-area-inset-bottom); }
main { max-width: 32rem; margin: 0 auto; padding: 1rem; }
header { display: flex; align-items: baseline; gap: .75rem; margin-bottom: .5rem; }
.brand { font-weight: 700; letter-spacing: .08em; color: var(--muted); }
h1 { font-size: 1.25rem; margin: 0; }
h2 { font-size: 1.05rem; margin: 0 0 .5rem; }
h3 { font-size: 1rem; margin: 0 0 .5rem; }
.panel { background: var(--panel); border: 1px solid var(--line); border-radius: 12px; padding: 1rem; margin-top: 1rem; }
.row { display: flex; justify-content: space-between; align-items: center; }
.note { color: var(--muted); font-size: .9rem; }
.code { font: 700 2.4rem/1.2 ui-monospace, SFMono-Regular, Menlo, monospace; letter-spacing: .12em; text-align: center; margin: .5rem 0; }
.cards { list-style: none; padding: 0; margin: 0; display: grid; gap: .75rem; }
.card { border: 1px solid var(--line); border-radius: 10px; padding: .75rem; }
dl { display: grid; grid-template-columns: auto 1fr; gap: .2rem .75rem; margin: 0 0 .75rem; font-size: .95rem; }
dt { color: var(--muted); }
dd { margin: 0; word-break: break-all; }
label { display: block; margin-bottom: .75rem; }
select { font: inherit; padding: .4rem; border-radius: 8px; border: 1px solid var(--line); background: var(--panel); color: var(--fg); }
.actions { display: flex; gap: .5rem; flex-wrap: wrap; margin-top: .5rem; }
button { font: inherit; padding: .7rem 1rem; border-radius: 10px; border: 1px solid var(--accent); background: var(--accent); color: var(--bg); cursor: pointer; min-height: 44px; }
button.secondary { background: transparent; color: var(--fg); border-color: var(--line); }
button:disabled { opacity: .5; cursor: default; }
#message:empty { display: none; }
#message { background: var(--panel); border-left: 4px solid var(--accent); padding: .5rem .75rem; border-radius: 6px; }