html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  font-family: 'Noto Sans Display', sans-serif;
}

.rootLayout {
  display: flex;
  height: 100vh;
  width: 100%;
}

.mainArea {
  display: flex;
  flex-direction: column; /* Header 在上, MainContent 在下 */
  flex: 1 1;
  height: 100vh;
  overflow: auto;          
  scrollbar-width: none; 
}