@charset "UTF-8";

:root {
  color-scheme: light;
  --text: #222;
  --muted: #666;
  --border: #ccc;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: #fff;
  color: var(--text);
  font: 14px/1.5 Arial, "Microsoft YaHei", sans-serif;
}
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: default; color: #999; background: #fafafa; }
:focus-visible { outline: 2px solid #555; outline-offset: 2px; }
[hidden] { display: none !important; }

.site-shell { max-width: 900px; margin: 28px auto; padding: 0 20px; }
.site-header { display: flex; align-items: center; justify-content: space-between; gap: 16px; margin-bottom: 20px; }
h1 { margin: 0; font-size: 24px; }
h2 { margin: 0; font-size: 16px; }
.workspace { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.panel { min-width: 0; padding: 18px; border: 1px solid var(--border); }
.panel-heading { display: flex; align-items: center; justify-content: space-between; gap: 8px; }

.display label, .result-label { display: block; color: var(--muted); font-size: 12px; }
#expression {
  display: block;
  width: 100%;
  margin: 6px 0 12px;
  padding: 8px 10px;
  border: 1px solid #aaa;
  border-radius: 2px;
  background: #fff;
  color: var(--text);
  font-size: 20px;
  text-align: right;
}
#result { display: block; min-height: 42px; text-align: right; overflow-wrap: anywhere; font-size: 28px; font-weight: 600; font-variant-numeric: tabular-nums; }
#result.long { font-size: 21px; }
.feedback { margin: 8px 0; color: var(--muted); font-size: 12px; }
.feedback:empty { margin: 0; }
.feedback.error { color: #a12622; }
.keypad { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin-top: 12px; }
.key { height: 44px; border: 1px solid #bbb; border-radius: 2px; background: #f5f5f5; color: var(--text); font-size: 20px; }
.key.utility { background: #eee; font-size: 17px; }
.key.operator { background: #eee; }
.key.equals { background: #ddd; border-color: #999; font-weight: 700; }
.key:not(:disabled):hover { background: #e3e3e3; }
.key:not(:disabled):active { background: #ccc; }

.history { display: flex; flex-direction: column; }
.history-title { display: flex; align-items: center; gap: 8px; }
.count { color: var(--muted); font-size: 12px; }
.count::before { content: "("; }
.count::after { content: ")"; }
.text-button { padding: 3px 8px; border: 1px solid var(--border); border-radius: 2px; background: #f5f5f5; color: var(--text); font-size: 12px; }
.history-list { flex: 1; margin: 12px 0 0; padding: 0; list-style: none; }
.history-row { display: flex; align-items: center; gap: 12px; padding: 10px 0; border-top: 1px solid #ddd; }
.history-entry { flex: 1; min-width: 0; border: 0; padding: 0; background: transparent; color: var(--text); text-align: left; }
.history-expression { display: block; overflow-wrap: anywhere; font-size: 13px; }
.history-result { display: block; overflow-wrap: anywhere; font-size: 18px; font-variant-numeric: tabular-nums; }
.history-time { display: block; margin-top: 2px; color: var(--muted); font-size: 12px; }
.delete-record { padding: 4px 7px; border: 1px solid var(--border); border-radius: 2px; background: #fff; color: var(--muted); font-size: 12px; }
.delete-record:hover { color: #a12622; border-color: #a12622; }
.history-state { flex: 1; display: grid; place-content: center; min-height: 220px; color: var(--muted); text-align: center; white-space: pre-line; }
.pagination { display: flex; justify-content: center; align-items: center; gap: 16px; margin-top: auto; padding-top: 14px; color: var(--muted); font-size: 12px; }
.pagination button { min-width: 30px; height: 28px; border: 1px solid var(--border); border-radius: 2px; background: #f5f5f5; color: var(--text); }
.pagination button:disabled { color: #aaa; background: #fafafa; }

dialog { width: min(400px, calc(100% - 32px)); padding: 20px; border: 1px solid #aaa; border-radius: 2px; color: var(--text); }
dialog::backdrop { background: #0005; }
#delete-description { overflow-wrap: anywhere; }
.dialog-note { color: var(--muted); font-size: 12px; }
.dialog-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 20px; }
.dialog-actions button { padding: 7px 14px; border: 1px solid #aaa; border-radius: 2px; background: #f5f5f5; color: var(--text); }
.dialog-actions .danger-button { color: #a12622; }

@media (max-width: 680px) {
  .site-shell { max-width: 480px; margin: 20px auto; padding: 0 14px; }
  .site-header { gap: 10px; margin-bottom: 14px; }
  h1 { font-size: 21px; }
  .workspace { grid-template-columns: 1fr; gap: 16px; }
  .panel { padding: 16px; }
  .history-state { min-height: 140px; }
}

@media (max-width: 360px) {
  .panel { padding: 12px; }
}