:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --text: #17202a;
  --muted: #657080;
  --line: #dfe4ea;
  --primary: #0d6efd;
  --primary-dark: #084298;
  --danger: #b42318;
  --success: #117a37;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.5;
}
a { color: var(--primary-dark); text-decoration: none; }
img { max-width: 100%; }

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 12px clamp(16px, 4vw, 42px);
  background: var(--surface);
  border-bottom: 1px solid var(--line);
}
.brand { font-weight: 800; color: var(--text); }
.top-search { flex: 1; }
.top-search input { width: 100%; max-width: 460px; }
nav { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.scan-link {
  color: white;
  background: var(--primary);
  padding: 9px 12px;
  border-radius: 8px;
}
.container { width: min(1180px, 100%); margin: 0 auto; padding: 24px clamp(16px, 4vw, 42px); }
.page-head, .section-head, .actions-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap; }
h1 { font-size: clamp(1.8rem, 3vw, 2.6rem); line-height: 1.1; margin: 0 0 18px; }
h2 { margin-top: 24px; }

input, select, textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 11px 12px;
  background: white;
  color: var(--text);
  font: inherit;
}
textarea { resize: vertical; }
label { display: grid; gap: 6px; color: var(--muted); font-weight: 650; }

.button, button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 10px 14px;
  background: white;
  color: var(--text);
  font-weight: 700;
  cursor: pointer;
}
.button.primary, button.primary { background: var(--primary); border-color: var(--primary); color: white; }
.button.danger, button.danger { background: var(--danger); border-color: var(--danger); color: white; margin-top: 16px; }

.flash { padding: 12px 14px; border-radius: 8px; background: white; border-left: 4px solid var(--primary); margin-bottom: 16px; }
.flash.danger { border-left-color: var(--danger); }
.flash.success { border-left-color: var(--success); }
.muted { color: var(--muted); }
.error { color: var(--danger); }

.auth-panel, .form, .preview-panel, .scanner-panel {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
}
.auth-panel { max-width: 420px; margin: 8vh auto; }
.form { display: grid; gap: 14px; max-width: 620px; }
.form.wide { max-width: 860px; }
.inline-form { margin-top: 16px; max-width: none; grid-template-columns: repeat(6, minmax(120px, 1fr)); align-items: end; }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
  margin: 18px 0;
}
.stats-grid article {
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 18px;
}
.stats-grid strong { display: block; font-size: 2rem; }
.stats-grid span { color: var(--muted); }

.filters { display: grid; grid-template-columns: 2fr repeat(6, minmax(110px, 1fr)) auto; gap: 10px; margin-bottom: 16px; }
.book-list { display: grid; gap: 8px; }
.book-row {
  display: grid;
  grid-template-columns: 54px 2fr 1fr 1.4fr .8fr;
  gap: 12px;
  align-items: center;
  padding: 10px;
  background: white;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--text);
}
.book-row img { width: 46px; height: 68px; object-fit: cover; background: #e9edf2; border-radius: 4px; }
.book-row small { display: block; color: var(--muted); }

.detail-layout { display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 24px; align-items: start; }
.cover-large { width: 220px; min-height: 320px; object-fit: cover; background: #e9edf2; border-radius: 8px; border: 1px solid var(--line); }
.meta { display: grid; grid-template-columns: 120px minmax(0, 1fr); gap: 8px 16px; }
.meta dt { color: var(--muted); font-weight: 700; }
.meta dd { margin: 0; }

.table-wrap { overflow-x: auto; background: white; border: 1px solid var(--line); border-radius: 8px; }
table { width: 100%; border-collapse: collapse; min-width: 720px; }
th, td { padding: 12px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
th { background: #f1f4f8; }

.scan-grid { display: grid; grid-template-columns: minmax(0, 1.2fr) 360px; gap: 18px; align-items: start; }
#reader { min-height: 320px; background: #111827; border-radius: 8px; overflow: hidden; }
.manual-isbn { display: grid; grid-template-columns: 1fr auto; gap: 10px; margin-top: 12px; }
.preview-panel { display: grid; gap: 12px; }
.preview-panel img { width: 130px; min-height: 190px; object-fit: cover; border: 1px solid var(--line); border-radius: 6px; }

@media (max-width: 820px) {
  .topbar { align-items: stretch; flex-direction: column; }
  nav { display: grid; grid-template-columns: repeat(3, 1fr); }
  .scan-link { text-align: center; }
  .stats-grid, .filters, .detail-layout, .scan-grid { grid-template-columns: 1fr; }
  .book-row { grid-template-columns: 48px 1fr; }
  .book-row span:nth-child(n+3) { display: none; }
  .inline-form { grid-template-columns: 1fr; }
  .manual-isbn { grid-template-columns: 1fr; }
}