css keep image ratio

img {
    display: block;
    max-width: 100%;
    max-height: 100%;
    width: auto;
    height: auto;
}

img {
  object-fit: cover;
  width: 100px;
  height:100px;
}

.container {
  padding-top: 66.66%; /* 
3:2 Aspect 
Ratio (divide 2 by 3 = 0.6666)   */
}
 

.container {
  padding-top: 62.5%; /* 
8:5 Aspect 
Ratio (divide 5 by 8 = 0.625) */
}
 

.container {
  padding-top: 75%; /* 
4:3 Aspect 
Ratio (divide 3 by 4 = 0.75)  */
}