Answers for "how to increase the border size in css"

border width css

.element {
  border-width: 2px;
}

border width css

element {
	border-width: 10px;
  	/* Or use shorthand border property */
  	/* width style colour */
  	border: 10px solid black;
}

border-width

border: 3px solid #3d3d3d
/* top | right | bottom | left */
border-width: 0 0 3px 3px

/*simulair to: */
border-left:  3px solid #3d3d3d
border-bottom:  3px solid #3d3d3d