Make an image grow proportionally to the limit of an area follow the example in the image below
max-width
div.imagem{
width: 210px;
height: 210px;
}
div.imagem img{
width: 100%;
max-width: 198px; // Sua Primeira Imagem
}
Use only the max-width property, as shown below:
div.imagem img{
max-width:100%;// primeira imagem
}
You have already defined the size of the area where the image will be inserted, so the image will occupy 100% of this area.