@import url('https://fonts.googleapis.com/css2?family=Rubik:wght@300;400;500;600;700;900&display=swap');

*{
  margin: 0;
  padding: 0;
  font-family: 'Rubik', sans-serif;

}

.container{
  border:5px solid black;
}

.flex-item{
  color:white;
  font-size: 18px;
  padding: 16px;
  text-align: center;
}

.box-1{background-color: #1abc9c;}
.box-2{background-color:#3498db;}
.box-3{background-color: #2ecc71;}
.box-4{background-color: #9b59b6;}
.box-5{background-color:#34495e;}
.box-6{background-color:#2980b9;}
.box-7{background-color:#e74c3c;}
.box-8{background-color: #d35400;}
.box-9{background-color:#2c3e50;}

/*-----------------------------------*/

.container{
  display: flex;
 
}

/* Flex-grow */
/* Flex-grow ,flex-basis (% px) */
/* Flex-grow , flex-shrink */
/* Flex-grow , flex-shrink , flex-basis */
.box-1{
flex:0 1 auto;
flex:0 1 200px;
flex:0 0 200px;
}