.header {
  background-color: darkred;
  padding: 5px;
}

body {
  margin: 0px;
  padding: 0px;
}

.container{
  display: flex;
}

.main {
  display: flex;
  
}

.menu {
 display: flex;
  flex-direction: column;
  justify-content: 20;
  background-color: #7d1717;
  right: 0;
  position: fixed;
  top: 0;
  bottom: 0;           
  width: 120px;        
  padding: 20px 10px;
}