CSS

arrow down css

.arrow-down {
  width: 0; 
  height: 0; 
  border-left: 75px solid transparent;
  border-right: 75px solid transparent;
  border-top: 75px solid #f00;
}

arrow left css

.arrow-left {
  width: 0; 
  height: 0; 
  border-top: 60px solid transparent;
  border-bottom: 60px solid transparent; 
  border-right: 60px solid blue; 
}

arrow up css

.arrow-up {
  width: 0; 
  height: 0; 
  border-left: 75px solid transparent;
  border-right: 75px solid transparent;
  border-bottom: 75px solid #761E9B;
}

arrow right css

.arrow-right {
  width: 0; 
  height: 0; 
  border-top: 60px solid transparent;
  border-bottom: 60px solid transparent;
  border-left: 60px solid green;
}

up arrow css

/*modify rotate value to change direction of arrow...*/
.arrow{
    border: solid black;
    border-width: 0 3px 3px 0;
    display: inline-block;
    padding: 3px;
    transform: rotate(-135deg);
    -webkit-transform: rotate(-135deg); 
}