frontend/src/components/Sidebar.css

.sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  background: var(--grad-sidebar);
  border-right: 1px solid var(--border-default);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  transition: width var(--transition-slow), opacity var(--transition-slow);
  backdrop-filter: blur(32px) saturate(1.5);
  -webkit-backdrop-filter: blur(32px) saturate(1.5);
  position: relative;
}

.sidebar::after {
  content: '';
  position: absolute;
  top: 0; right: -1px;
  width: 1px; height: 100%;
  background: linear-gradient(180deg,
    transparent 0%,
    rgba(59,142,255,0.5) 30%,
    rgba(0,229,255,0.7) 55%,
    rgba(155,109,255,0.5) 80%,
    transparent 100%
  );
  animation: meshDrift 8s ease-in-out infinite alternate;
}

.sidebar--closed {
  width: 0;
  opacity: 0;
  pointer-events: none;
}

.sidebar__header {
  padding: 16px 12px 10px;
  flex-shrink: 0;
}

.sidebar__new-chat {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 11px 16px;
  background: linear-gradient(135deg, var(--accent-blue) 0%, #6A3DFF 100%);
  border: none;
  border-radius: var(--radius-md);
  color: white;
  font-family: var(--font-sans);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-base);
  letter-spacing: -0.01em;
  box-shadow: 0 4px 20px rgba(59,142,255,0.4), 0 0 0 1px rgba(255,255,255,0.08) inset;
  position: relative;
  overflow: hidden;
}

.sidebar__new-chat::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.12) 0%, transparent 60%);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.sidebar__new-chat:hover::before { opacity: 1; }
.sidebar__new-chat:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 28px rgba(59,142,255,0.55), 0 0 0 1px rgba(255,255,255,0.12) inset;
}
.sidebar__new-chat:active { transform: translateY(0); }

.sidebar__section {
  padding: 6px 12px 14px;
  flex-shrink: 0;
}

.sidebar__section:nth-child(3) {
  flex: 1;
  overflow-y: auto;
}

.sidebar__label {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-tertiary);
  padding: 0 4px;
  margin-bottom: 8px;
}

.sidebar__history {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar__chat-item {
  display: flex;
  align-items: center;
  gap: 9px;
  width: 100%;
  padding: 9px 11px;
  border-radius: var(--radius-sm);
  background: none;
  border: 1px solid transparent;
  color: var(--text-secondary);
  font-family: var(--font-sans);
  font-size: 13px;
  cursor: pointer;
  text-align: left;
  transition: all var(--transition-fast);
  white-space: nowrap;
  overflow: hidden;
}

.sidebar__chat-item:hover {
  background: var(--bg-glass);
  border-color: var(--border-subtle);
  color: var(--text-primary);
}

.sidebar__chat-item--active {
  background: var(--accent-blue-soft);
  border-color: rgba(59,142,255,0.25);
  color: var(--accent-cyan);
  box-shadow: 0 0 16px rgba(59,142,255,0.1) inset;
}

.sidebar__chat-item--active svg { color: var(--accent-blue); }
.sidebar__chat-title { overflow: hidden; text-overflow: ellipsis; flex: 1; }

.sidebar__config-group { margin-bottom: 20px; }

.sidebar__config-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 9px;
  letter-spacing: -0.01em;
}

.sidebar__config-value {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent-cyan);
  background: var(--accent-cyan-soft);
  border: 1px solid rgba(0,229,255,0.18);
  padding: 2px 8px;
  border-radius: 5px;
  box-shadow: 0 0 8px rgba(0,229,255,0.12);
}

.sidebar__select {
  width: 100%;
  padding: 9px 32px 9px 11px;
  background: var(--bg-glass);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 12.5px;
  cursor: pointer;
  outline: none;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='rgba(100,180,255,0.5)' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 10px center;
  transition: all var(--transition-fast);
}

.sidebar__select option { background: #0d1020; color: white; }
.sidebar__select:focus {
  border-color: var(--border-glow);
  box-shadow: 0 0 0 2px rgba(59,142,255,0.12), 0 0 16px rgba(59,142,255,0.1);
}

.sidebar__range {
  width: 100%;
  height: 3px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--border-default);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}

.sidebar__range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 15px;
  height: 15px;
  background: radial-gradient(circle, #fff 30%, var(--accent-cyan) 100%);
  border-radius: 50%;
  box-shadow: 0 0 10px rgba(0,229,255,0.7), 0 0 20px rgba(59,142,255,0.4);
  transition: all var(--transition-fast);
  border: 2px solid rgba(0,229,255,0.4);
}

.sidebar__range::-webkit-slider-thumb:hover {
  transform: scale(1.25);
  box-shadow: 0 0 16px rgba(0,229,255,0.9), 0 0 30px rgba(59,142,255,0.5);
}

.sidebar__range-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 6px;
  font-size: 10px;
  color: var(--text-tertiary);
}

.sidebar__footer {
  padding: 12px;
  border-top: 1px solid var(--border-subtle);
}

.sidebar__footer-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  background: linear-gradient(135deg, rgba(59,142,255,0.08), rgba(155,109,255,0.06));
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  font-size: 11.5px;
  font-weight: 500;
  color: var(--text-tertiary);
  letter-spacing: -0.01em;
}

.sidebar__footer-badge svg { color: var(--accent-blue); opacity: 0.7; }