:root {
  --bg: #282a36;
  --panel: #21222c;
  --current-line: #44475a;
  --fg: #f8f8f2;
  --muted: #6272a4;
  --accent: #bd93f9;
  --green: #50fa7b;
  --red: #ff5555;
  --orange: #ffb86c;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: "Segoe UI", Roboto, Arial, sans-serif;
  background-color: var(--bg);
  color: var(--fg);
  overflow: hidden;
}

.app-container {
  display: flex;
  height: 100vh;
  width: 100vw;
}

/* Sidebar Styles */
.sidebar {
  background-color: var(--panel);
  border-right: 1px solid var(--current-line);
  transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
  position: relative;
  width: 220px;
}

.sidebar.collapsed {
  width: 60px;
}

.sidebar-content {
  display: flex;
  flex-direction: column;
  height: 100%;
  padding: 8px;
}

.toggle-btn {
  background: transparent;
  color: var(--muted);
  border: none;
  font-size: 20px;
  cursor: pointer;
  padding: 8px;
  margin-bottom: 8px;
  text-align: left;
  transition: color 0.2s;
}

.toggle-btn:hover {
  color: var(--fg);
}

.nav-menu {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.nav-btn {
  background: transparent;
  color: var(--fg);
  border: none;
  border-radius: 6px;
  cursor: pointer;
  padding: 12px 8px;
  text-align: left;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 14px;
}

.sidebar.collapsed .nav-text {
  display: none;
}

.nav-emoji {
  font-size: 18px;
  min-width: 24px;
}

.nav-btn:hover {
  background-color: var(--current-line);
}

.nav-btn.active {
  background-color: var(--current-line);
  color: var(--accent);
}

.sidebar-footer {
  margin-top: auto;
}

.exit-btn {
  color: var(--red);
}

.exit-btn:hover {
  background-color: var(--current-line);
}

/* Main Content */
.main-content {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
}

.page {
  animation: fadeIn 0.3s ease-in;
}

.page.hidden {
  display: none;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.page-title {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 8px;
}

.page-subtitle {
  color: var(--muted);
  margin-bottom: 24px;
  font-size: 14px;
}

/* Control Panel */
.control-panel {
  background-color: var(--panel);
  border: 1px solid var(--muted);
  border-radius: 8px;
  padding: 16px;
  margin-bottom: 20px;
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  align-items: center;
}

.control-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.control-group label {
  color: var(--muted);
  font-size: 14px;
}

.control-group select {
  background-color: var(--bg);
  color: var(--fg);
  border: 1px solid var(--current-line);
  border-radius: 4px;
  padding: 6px 12px;
  cursor: pointer;
  font-size: 14px;
}

.control-group select:hover {
  border-color: var(--accent);
}

.button-group {
  display: flex;
  gap: 8px;
  margin-left: auto;
}

.btn-run,
.btn-stop,
.btn-train {
  border: none;
  border-radius: 6px;
  padding: 8px 16px;
  cursor: pointer;
  font-size: 14px;
  transition: all 0.2s;
}

.btn-run {
  background-color: var(--green);
  color: var(--bg);
}

.btn-run:hover {
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(80, 250, 123, 0.3);
}

.btn-stop {
  background-color: var(--red);
  color: var(--bg);
}

.btn-stop:hover {
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(255, 85, 85, 0.3);
}

.btn-train {
  background-color: var(--accent);
  color: var(--bg);
  margin-top: 16px;
}

/* Visualization Panel */
.visualization-panel {
  background-color: var(--panel);
  border: 1px solid var(--muted);
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 20px;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 450px;
}

#pendulumCanvas {
  background-color: var(--bg);
  border-radius: 4px;
  width: 100%;
  height: auto;
  max-width: 800px;
}

/* Stats Panel */
.stats-panel {
  background-color: var(--panel);
  border: 1px solid var(--muted);
  border-radius: 8px;
  padding: 16px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}

.stat {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 12px;
  background-color: var(--bg);
  border-radius: 6px;
}

.stat-label {
  color: var(--muted);
  font-size: 13px;
}

.stat-value {
  color: var(--accent);
  font-size: 18px;
  font-weight: 600;
  font-family: monospace;
}

/* Cards */
.welcome-card,
.info-card {
  background-color: var(--panel);
  border: 1px solid var(--current-line);
  border-radius: 8px;
  padding: 32px;
  text-align: center;
}

.welcome-card h2,
.info-card h3 {
  color: var(--accent);
  margin-bottom: 16px;
}

.welcome-card p,
.info-card p {
  color: var(--muted);
  margin-bottom: 12px;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--panel);
}

::-webkit-scrollbar-thumb {
  background: var(--current-line);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--muted);
}

/* Responsive */
@media (max-width: 768px) {
  .control-panel {
    flex-direction: column;
    align-items: stretch;
  }

  .button-group {
    margin-left: 0;
  }

  .stats-panel {
    grid-template-columns: 1fr;
  }
}