.header {
  display: flex;
  justify-content: space-between;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 45px;
  
  z-index: 100;

  background-color: var(--container-bg);
  border-bottom: 1px solid var(--border-color);
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.left-section {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-left: 20px;
}

.task-image {
  height: 24px;
  filter: invert(0%);
  transition: filter 0.2s ease;
}

.task-image:hover {
  transform: rotate(10deg) scale(1.1);
}

.dark-mode .task-image {
  filter: invert(100%);
}

.brand-name {
  font-family: Montserrat;
  font-weight: 600;
  font-size: 1.1rem;
  color: var(--heading-color);
  transition: color 0.2s ease;
}

.brand-name span {
  color: #4CAF50;
}

.right-section {
  display: flex;
  align-items: center;
  margin-right: 20px;
}

.dark-mode-button {
  border: none;
  background-color: transparent;
  cursor: pointer;
}

.dark-mode-image {
  height: 24px;
  filter: invert(0%);
  transition: filter 0.2s ease;
}

.dark-mode .dark-mode-image {
  filter: invert(100%);
}


@media(max-width: 450px) {
  .header {
    height: 40px;
  }

  .brand-name {
    font-size: 0.95rem;
  }

  .task-image, .dark-mode-image {
    height: 20px;
  }

  .left-section {
   margin-left: 15px;
  }

  .right-section {
    margin-right: 15px;
  }

  .task-image:hover {
    transform: none;
  }
}