:root {
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  color-scheme: light;
  --background: #ffffff; --surface: #f4f7fb; --ink: #202e44;
  --muted: #52647b; --line: #d9e1ed; --accent: #245eb8; --on-accent: #ffffff;
  --error: #a12831; --focus: #245eb8;
  color: var(--ink); background: var(--background);
  font-synthesis: none; line-height: 1.6; font-size: 15px;
}
:root[data-theme="dark"] {
  color-scheme: dark;
  --background: #121a26; --surface: #1b283a; --ink: #edf2fa;
  --muted: #b1bfd3; --line: #36485f; --accent: #96c0ff; --on-accent: #10294d;
  --error: #ffb2b7; --focus: #96c0ff;
}
* { box-sizing: border-box; }
body { margin: 0; min-width: 0; }
[hidden] { display: none !important; }
main { max-width: 760px; margin: 0 auto; padding-bottom: env(safe-area-inset-bottom, 0px); }
.toolbar { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 16px; padding: 16px 20px; border-bottom: 1px solid var(--line); }
h1 { font-size: 20px; font-weight: 650; margin: 0; letter-spacing: .04em; }
.target-label { display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--muted); }
select, button { font: inherit; min-height: 44px; border-radius: 8px; border: 1px solid var(--line); color: var(--ink); background: var(--background); }
select { min-width: 122px; max-width: 100%; padding: 6px 10px; }
button { padding: 8px 16px; cursor: pointer; font-size: 14px; font-weight: 550; }
button:hover:enabled { background: var(--surface); }
button.primary { color: var(--on-accent); background: var(--accent); border-color: var(--accent); }
button.primary:hover:enabled { filter: brightness(.94); background: var(--accent); }
button:disabled, select:disabled { opacity: .55; cursor: default; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }
.content { padding: 20px; }
.notice { border-left: 3px solid var(--accent); padding: 8px 12px; font-size: 13px; color: var(--muted); background: var(--surface); margin-bottom: 24px; }
.section-heading { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; }
h2 { font-size: 13px; color: var(--muted); font-weight: 550; margin: 0; }
.language { color: var(--muted); font-size: 12px; }
.text { white-space: pre-wrap; overflow-wrap: anywhere; word-break: normal; margin: 10px 0 0; }
.original { font-size: 14px; color: var(--muted); line-height: 1.85; }
.source-section { padding-bottom: 24px; border-bottom: 1px solid var(--line); }
.result-section { padding-top: 22px; }
.translated { font-size: 17px; line-height: 1.9; min-height: 100px; }
main[data-state="loading"] .translated, main[data-state="idle"] .translated { color: var(--muted); }
.status { color: var(--muted); font-size: 13px; margin: 20px 0 12px; min-height: 24px; }
main[data-state="error"] .status { color: var(--error); }
.actions { display: flex; flex-wrap: wrap; gap: 12px; justify-content: flex-end; }
.footnote { color: var(--muted); font-size: 12px; margin: 20px 0 0; }
@media (max-width: 350px) { .toolbar { padding: 12px 16px; } .content { padding: 16px; } button { padding-inline: 12px; } }
@media (prefers-reduced-motion: no-preference) { button { transition: background-color .12s; } }