:root {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.5;
  font-weight: 400;

  color-scheme: light dark;
  --bg-color: #ffffff;
  --text-color: #213547;
  --sidebar-bg: #f8f9fa;
  --border-color: #e9ecef;
  --accent-color: #007bff;
  --hover-color: #e2e6ea;
  --sidebar-width: 250px;
  --item-list-width: 350px;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-color: #1a1a1a;
    --text-color: #e9ecef;
    --sidebar-bg: #2d2d2d;
    --border-color: #444;
    --accent-color: #375a7f;
    --hover-color: #3e3e3e;
  }
}

body {
  margin: 0;
  color: var(--text-color);
  background-color: var(--bg-color);
  height: 100vh;
  overflow: hidden;
}

#app {
  height: 100%;
}

.layout {
  display: flex;
  height: 100%;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--sidebar-bg);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  padding: 1rem;
  border-bottom: 1px solid var(--border-color);
}

.sidebar-header h2 {
  margin: 0;
  font-size: 1.1rem;
}

.feed-list {
  list-style: none;
  padding: 0;
  margin: 0;
  overflow-y: auto;
  flex: 1;
}

.feed-link {
  display: block;
  padding: 0.5rem 1rem;
  text-decoration: none;
  color: var(--text-color);
  font-size: 0.9rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.feed-item:hover {
  background-color: var(--hover-color);
}

.feed-item.active {
  background-color: var(--hover-color);
  font-weight: bold;
}

/* Item List Pane */
.item-list-pane {
  width: var(--item-list-width);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  background-color: var(--bg-color);
}

.top-bar {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border-color);
}

.top-bar h1 {
  margin: 0;
  font-size: 1rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.item-list-container {
  flex: 1;
  overflow-y: auto;
}

.item-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.item-row {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border-color);
  cursor: pointer;
  transition: background 0.1s;
}

.item-row:hover {
  background-color: var(--hover-color);
}

.item-row.active {
  background-color: var(--hover-color);
  border-left: 3px solid var(--accent-color);
}

.item-row.read {
  opacity: 0.6;
}

.item-title {
  font-weight: 600;
  font-size: 0.95rem;
  margin-bottom: 0.2rem;
  line-height: 1.3;
}

.item-meta {
  font-size: 0.8rem;
  color: #888;
}

/* Item Detail Pane */
.item-detail-pane {
  flex: 1;
  overflow-y: auto;
  background-color: var(--bg-color);
}

.item-detail-content {
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem;
}

.item-detail header {
  margin-bottom: 2rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1rem;
}

.item-detail h1 {
  font-size: 1.8rem;
  margin: 0 0 0.5rem 0;
}

.item-detail h1 a {
  color: var(--text-color);
  text-decoration: none;
}

.full-content {
  font-size: 1.1rem;
  line-height: 1.6;
}

.full-content img {
  max-width: 100%;
  height: auto;
}

.empty-state {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;
  color: #888;
  font-size: 1.2rem;
}

.loading,
.empty {
  padding: 1rem;
  text-align: center;
  color: #888;
}