:root {
  color-scheme: light dark;
  --bg: #f5f5f5;
  --fg: #1a1a1a;
  --card-bg: #ffffff;
  --border: #ddd;
  --accent: #2563eb;
  --error: #c0392b;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121212;
    --fg: #eee;
    --card-bg: #1e1e1e;
    --border: #333;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}
.topnav {
  display: flex;
  gap: 12px;
  padding: 10px 16px;
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  align-items: center;
  flex-wrap: wrap;
}
.topnav a { color: var(--accent); text-decoration: none; font-size: 14px; }
.logout-form { margin-left: auto; }
.logout-form button {
  background: none; border: 1px solid var(--border); border-radius: 6px;
  padding: 4px 10px; color: var(--fg); font-size: 13px;
}
.container { max-width: 640px; margin: 0 auto; padding: 16px; }
h1 { font-size: 20px; }
h2 { font-size: 16px; margin-top: 28px; }
.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  margin-bottom: 12px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
label { font-size: 13px; font-weight: 600; }
input, select {
  font-size: 16px;
  padding: 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  color: var(--fg);
  width: 100%;
}
button {
  font-size: 16px;
  padding: 12px;
  border: none;
  border-radius: 8px;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
}
/* スマホで押しやすい撮影/選択ボタン */
.big-choice {
  display: block;
  width: 100%;
  padding: 18px;
  font-size: 17px;
  margin-bottom: 10px;
}
.big-choice.secondary {
  background: var(--card-bg);
  color: var(--accent);
  border: 1px solid var(--accent);
}
.error { color: var(--error); font-size: 14px; }
.hint { color: #888; font-size: 14px; }
.preview { max-width: 100%; border-radius: 8px; margin-top: 8px; }
.receipt-list { list-style: none; padding: 0; }
.receipt-list a { display: flex; gap: 12px; align-items: center; text-decoration: none; color: var(--fg); }
.thumb { width: 64px; height: 64px; object-fit: cover; border-radius: 6px; }
.review-layout { display: flex; flex-direction: column; gap: 16px; }
.review-image { max-width: 100%; border-radius: 8px; border: 1px solid var(--border); }
.ocr-raw pre { white-space: pre-wrap; font-size: 12px; max-height: 200px; overflow-y: auto; }