:root {
  --bg: #ffffff;
  --panel: #f6f7f8;
  --border: #d0d7de;
  --text: #111827;
  --muted: #6b7280;
  --focus: #2563eb;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
}

.header-actions {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

button, .button {
  border: 1px solid var(--border);
  background: #fff;
  padding: 0.4rem 0.6rem;
  border-radius: 6px;
  cursor: pointer;
  font: inherit;
  color: inherit;
  text-decoration: none;
}

button:hover, .button:hover { border-color: #9ca3af; }

#app {
  display: flex;
  gap: 1rem;
  padding: 1rem;
  overflow-x: auto;
  min-height: calc(100vh - 120px);
}

.column {
  width: 320px;
  flex: 0 0 auto;
}

.card {
  border: 1px solid var(--border);
  border-radius: 8px;
  background: #fff;
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.card.active {
  border-color: var(--focus);
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.15);
}

.card textarea {
  width: 100%;
  border: 0;
  padding: 0.75rem;
  resize: vertical;
  min-height: 80px;
  font: inherit;
  line-height: 1.4;
  outline: none;
}

.app-footer {
  padding: 0.75rem 1rem;
  border-top: 1px solid var(--border);
  background: var(--panel);
}

.app-footer a { color: inherit; }

.page .page-content {
  padding: 1rem;
  max-width: 860px;
}