.header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  background: rgba(3, 4, 12, 0.85);
  border-bottom: 1px solid var(--border-default);
  backdrop-filter: blur(28px) saturate(1.4);
  -webkit-backdrop-filter: blur(28px) saturate(1.4);
  flex-shrink: 0;
  position: relative;
  z-index: 10;
}

.header::after {
  content: '';
  position: absolute;
  bottom: -1px; left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg,
    transparent 0%,
    rgba(59,142,255,0.6) 20%,
    rgba(0,229,255,0.9) 50%,
    rgba(155,109,255,0.6) 80%,
    transparent 100%
  );
  animation: shimmer 4s linear infinite;
  background-size: 300% 100%;
}

.header__left {
  display: flex;
  align-items: center;
  gap: 14px;
}

.header__sidebar-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  background: var(--bg-glass);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-tertiary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.header__sidebar-toggle:hover {
  background: var(--accent-blue-soft);
  border-color: var(--border-default);
  color: var(--accent-cyan);
  box-shadow: var(--shadow-glow-blue);
}

.header__brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.header__atom {
  animation: spin 10s linear infinite;
  display: flex;
  align-items: center;
  filter: drop-shadow(0 0 8px rgba(59,142,255,0.7)) drop-shadow(0 0 16px rgba(0,229,255,0.4));
}

.header__title {
  font-size: 15.5px;
  font-weight: 600;
  letter-spacing: -0.025em;
  background: linear-gradient(135deg, #fff 30%, var(--accent-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  animation: textGlow 4s ease-in-out infinite;
}

.header__subtitle {
  font-size: 10px;
  color: var(--text-tertiary);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-top: 3px;
  font-weight: 500;
}

.header__right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.header__model-chip {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 13px;
  background: var(--accent-violet-soft);
  border: 1px solid rgba(155,109,255,0.25);
  border-radius: var(--radius-sm);
  font-size: 11.5px;
  font-weight: 500;
  color: var(--accent-violet);
  letter-spacing: -0.01em;
  box-shadow: 0 0 12px rgba(155,109,255,0.12);
}

.header__status {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 6px 13px;
  background: var(--bg-glass);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  backdrop-filter: blur(8px);
}

.header__status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  display: block;
  animation: glowPulse 2.2s ease-in-out infinite;
}

.header__status-text {
  font-size: 11.5px;
  font-weight: 500;
  color: var(--text-secondary);
  letter-spacing: -0.01em;
}