:root {
  --bg: #f4f6f8;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --border: #e5e7eb;
  --danger: #dc2626;
  --danger-hover: #b91c1c;
  --success: #16a34a;
  --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --radius: 12px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

h1 {
  text-align: center;
  margin-bottom: 24px;
  font-size: 1.6rem;
}

.card {
  background: var(--card);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
  margin-bottom: 20px;
}

h2 {
  margin: 0 0 16px;
  font-size: 1.15rem;
}

.drop-zone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 32px 16px;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
}

.drop-zone:hover,
.drop-zone.drag-over {
  border-color: var(--primary);
  background: #eff6ff;
}

.file-name {
  margin: 12px 0 0;
  font-size: 0.9rem;
  color: var(--muted);
  min-height: 1.4em;
}

.form-row {
  display: flex;
  gap: 8px;
  margin-top: 12px;
  flex-wrap: wrap;
}

input[type="text"],
select {
  flex: 1;
  min-width: 160px;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  font-size: 0.95rem;
  outline: none;
}

input[type="text"]:focus,
select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

button {
  padding: 10px 14px;
  border: none;
  border-radius: 8px;
  background: var(--primary);
  color: #fff;
  font-size: 0.95rem;
  cursor: pointer;
  transition: background 0.2s;
}

button:hover:not(:disabled) {
  background: var(--primary-hover);
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.status {
  margin-top: 10px;
  font-size: 0.9rem;
  color: var(--muted);
  min-height: 1.4em;
}

.filter-row {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

th,
td {
  text-align: left;
  padding: 10px 8px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

th {
  color: var(--muted);
  font-weight: 600;
}

.thumb {
  width: 48px;
  height: 48px;
  object-fit: cover;
  border-radius: 8px;
  background: var(--bg);
}

.link-btn {
  background: transparent;
  color: var(--primary);
  padding: 6px 10px;
  border: 1px solid var(--border);
}
.link-btn:hover {
  background: #eff6ff;
}

.danger-btn {
  background: var(--danger);
}
.danger-btn:hover {
  background: var(--danger-hover);
}

.small-btn {
  padding: 6px 10px;
  font-size: 0.85rem;
  margin-left: 4px;
}

#category-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

#category-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 8px;
  border-bottom: 1px solid var(--border);
}

.cat-name {
  flex: 1;
  margin-right: 8px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.toast {
  position: fixed;
  right: 16px;
  bottom: 16px;
  background: var(--text);
  color: #fff;
  padding: 12px 16px;
  border-radius: 10px;
  box-shadow: var(--shadow);
  max-width: 360px;
  z-index: 1000;
  transition: opacity 0.3s, transform 0.3s;
  opacity: 1;
  transform: translateY(0);
}

.toast.hidden {
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
}

.toast.error {
  background: var(--danger);
}

.toast.success {
  background: var(--success);
}

@media (max-width: 640px) {
  .container {
    padding: 16px 12px 40px;
  }
  h1 {
    font-size: 1.3rem;
  }
  th,
  td {
    padding: 8px 6px;
    font-size: 0.85rem;
  }
  .thumb {
    width: 36px;
    height: 36px;
  }
}