/* === Base === */
body {
  margin: 0;
  font-family: "Segoe UI", Arial, sans-serif;
  background-color: var(--bg);
  color: var(--text);
  transition: background-color 0.3s, color 0.3s;
}

/* === Theme variables === */
:root {
  --bg: #fafafa;
  --text: #111;
  --panel-bg: #f3f4f6;
  --panel-border: #ddd;
  --active-bg: #d1e3ff;
  --active-text: #003366;
}

body.dark {
  --bg: #1e1e1e;
  --text: #e8e8e8;
  --panel-bg: #2c2c2c;
  --panel-border: #444;
  --active-bg: #3b5998;
  --active-text: #fff;
}

/* === Header === */
#topbar {
  display: flex;
  justify-content: flex-start;
  align-items: center;
  padding: 10px 16px;
  background-color: var(--panel-bg);
  border-bottom: 1px solid var(--panel-border);
}

#topbar h1 {
  font-size: 1.1em;
  margin: 0 10px 0 0;
}

#top-buttons {
  display: flex;
  gap: 8px;
  margin-left: auto;
}

#themeToggle, #togglePanels {
  background: none;
  border: none;
  font-size: 1.4em;
  cursor: pointer;
  color: var(--text);
  transition: transform 0.2s;
}

#themeToggle:hover, #togglePanels:hover {
  transform: scale(1.2);
}

/* === Ribbon === */
#ribbon {
  display: flex;
  background-color: var(--panel-bg);
  border-bottom: 1px solid var(--panel-border);
}

.ribbon-item {
  padding: 10px 15px;
  cursor: pointer;
  transition: background-color 0.3s;
  color: var(--text);
}

.ribbon-item:hover {
  background-color: rgba(0,0,0,0.05);
}

.ribbon-item.active {
  background-color: var(--active-bg);
  color: var(--active-text);
  font-weight: bold;
}

/* === Layout === */
#app {
  display: flex;
  height: calc(100vh - 70px); /* Adjusted for ribbon height */
  overflow: hidden;
  transition: all 0.3s ease;
}

/* Panels */
#categories, #subcategories {
  width: 12%;
  border-right: 1px solid var(--panel-border);
  overflow-y: auto;
  padding: 10px;
  background-color: var(--panel-bg);
  transition: transform 0.4s ease, width 0.3s ease;
}

/* Hide panels mode */
body.hide-panels #categories,
body.hide-panels #subcategories {
  transform: translateX(-100%);
  width: 0;
  padding: 0;
  border: none;
}

body.hide-panels #content {
  flex: 1 1 100%;
}

/* Content */
#content {
  flex: 1;
  padding: 20px;
  overflow-y: auto;
  background-color: var(--bg);
}

/* === List items === */
.category, .subcategory {
  padding: 8px;
  margin-bottom: 6px;
  border-radius: 6px;
  cursor: pointer;
  transition: background-color 0.3s;
}

.category:hover, .subcategory:hover {
  background-color: rgba(0,0,0,0.05);
}

.category.active, .subcategory.active {
  background-color: var(--active-bg);
  color: var(--active-text);
  font-weight: bold;
}

/* === Slide animation for subcategories === */
.slide-panel {
  animation: slideIn 0.4s ease;
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-15px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* === Search Input === */
#searchInput {
  padding: 8px;
  border: 1px solid var(--panel-border);
  border-radius: 4px;
  background-color: var(--panel-bg);
  color: var(--text);
  font-size: 1em;
  margin-left: 10px;
  width: 200px;
  transition: width 0.3s, background-color 0.3s;
}

#searchInput:focus {
  width: 250px;
  outline: none;
  border-color: var(--active-bg);
}

body.dark #searchInput {
  background-color: var(--panel-bg);
  border-color: var(--panel-border);
}

.no-results {
  padding: 10px;
  color: var(--text);
  font-style: italic;
}

/* === Responsive === */
@media (max-width: 768px) {
  #app {
    flex-direction: column;
  }
  #categories, #subcategories {
    width: 100%;
    border-right: none;
    border-bottom: 1px solid var(--panel-border);
  }
  #ribbon {
    flex-wrap: wrap;
  }
}