Borders

The border helper classes allow, as their name implies, setting an element's border properties. Specifically, utility classes allow for the quick setting of border, border-top, border-bottom, border-left, border-right, and border-color. Border helper classes also allow rounding borders through setting the border-radius properties.

First and foremost, to create a solid 1 px border around an element, use the border class. Similarly, to remove the border around an element, use the border-0 class. To clear the top, bottom, left, or right borders, use the border-top-0, border-bottom-0, border-left-0, and border-right-0 classes respectively. Bootstrap defines these classes as follows:

.border {
  border: 1px solid #dee2e6 !important;
}

.border-0 {
    border: 0 !important;
 }

.border-top-0 {
    border-top: 0 !important;
 }

.border-right-0 {
    border-right: 0 !important;
 }

.border-bottom-0 {
    border-bottom: 0 !important;
}

.border-left-0 {
    border-left: 0 !important;
 }

To round...