:root {
  color-scheme: light dark;
  --bg: #ecf2ed;
  --surface: #fcfffc;
  --ink: #173326;
  --muted: #486256;
  --border: #c7d9cd;
  --accent: #176343;
  --on-accent: #fff;
  --result: #e2f1e8;
  --error: #a32436;
  font-family: system-ui, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12231c;
    --surface: #1a3026;
    --ink: #f1fcf4;
    --muted: #b8cfc0;
    --border: #476256;
    --accent: #9ee7b9;
    --on-accent: #0b2f1c;
    --result: #234233;
    --error: #ffacb4;
  }
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }
body { margin: 0; background: var(--bg); color: var(--ink); }
main {
  width: min(100%, 580px);
  margin: 0 auto;
  padding: max(22px, env(safe-area-inset-top)) 18px max(26px, env(safe-area-inset-bottom));
}
.masthead {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 19px 2px;
  color: var(--accent);
  font-size: .75rem;
  font-weight: 800;
  letter-spacing: .17em;
}
.hero, #recent {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 21px;
  padding: clamp(17px, 5vw, 30px);
}
h1 { margin: 0; font-size: clamp(1.85rem, 8vw, 2.7rem); letter-spacing: -.052em; line-height: 1.07; }
h2 { margin: 0 0 10px; font-size: 1.08rem; }
p { color: var(--muted); line-height: 1.45; }
.hero > p { margin: 9px 0 19px; }
form { display: grid; gap: 8px; }
label { display: block; margin-bottom: 4px; font-size: .875rem; font-weight: 700; }
input, button { font: inherit; border-radius: 11px; min-height: 46px; }
input {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid var(--border);
  color: var(--ink);
  background: var(--surface);
}
input::placeholder { color: var(--muted); }
button {
  padding: 9px 14px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--ink);
  font-weight: 700;
  cursor: pointer;
}
button:disabled { opacity: .62; cursor: default; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.primary { background: var(--accent); color: var(--on-accent); border-color: transparent; }
#status { margin: 10px 0 0; font-size: .88rem; }
#status:empty { display: none; }
#status[data-error="true"] { color: var(--error); }
.result { margin-top: 14px; padding: 13px; background: var(--result); border-radius: 14px; }
.actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 9px; }
.actions button { flex: 1; }
#recent { margin-top: 14px; }
#history-status { margin: 0; font-size: .9rem; }
#history { margin: 0; padding: 0; list-style: none; }
#history li { display: grid; gap: 3px; padding: 9px 0; border-top: 1px solid var(--border); }
#history a { color: var(--accent); overflow-wrap: anywhere; font-weight: 650; }
#history time { color: var(--muted); font-size: .78rem; }