div {
  width: 0;
  height: 0;
  border: 10px solid transparent;
  border-bottom-color: #f00;
}
div {
  width: 0;
  height: 0;
  border: 20px solid #f00;
  border-top-color: #00f;
}
div {
  width: 0;
  height: 0;
  border: 5px solid transparent;
  border-right-color: rgba(12,23,45,0.7);
}
div {
  width: 0;
  height: 0;
  border: 1px solid transparent;
  border-left-color: #fff;
}
div {
  width: 0;
  height: 0;
  border: 10px solid transparent;
  border-top-color: #f00;
  border-left-color: #f00;
}
div {
  width: 0;
  height: 0;
  border: 10px solid transparent;
  border-top-color: #f00;
  border-right-color: #f00;
}
div {
  width: 0;
  height: 0;
  border: 10px solid transparent;
  border-bottom-color: #f00;
  border-left-color: #f00;
}
div {
  width: 0;
  height: 0;
  border: 10px solid #00f;
  border-bottom-color: #f00;
  border-right-color: #f00;
}