* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  -o-box-sizing: border-box;
}
:root {
  /* Variables for assignment 01 */
  --bg-color-1: #ff5722;
  --txt-color-1: #fff;
  /* Variables for assignment 02 */
  --bg-color-2: #009688;
  --txt-color-2: #fff;
  /* Variables for assignment 04 */
  --black-color-4: #000000;
  --gray-color-4: #607d8b;
  /* Variables for assignment 05 */
  --purple-color-5: #fa3664;
  --blue-color-5: #0075ff;
}
hr {
  margin: 50px;
}
/* Assignment 01 */
.assign-1 {
  margin-top: 40px;
  margin-inline: auto;
  color: var(--txt-color-1);
  background-color: var(--bg-color-1);
  width: 150px;
  text-align: center;
  position: relative;
  font-size: 40px;
  padding: 10px;
}
.assign-1::after,
.assign-1::before {
  content: "";
  width: 100%;
  height: 100%;
  position: absolute;
  background-color: inherit;
  top: 0;
  z-index: -1;
}
.assign-1::after {
  transform: skew(10deg, 10deg);
  right: 0;
}
.assign-1::before {
  transform: skew(-10deg, -10deg);
  left: 0;
}
/* Assignment 02 */
.assign-2 {
  color: var(--txt-color-2);
  background-color: var(--bg-color-2);
  padding: 10px;
  padding-block: 20px;
  margin-inline: auto;
  width: 200px;
  text-align: right;
  font-size: 3rem;
  position: relative;
}
.assign-2::before {
  content: "";
  position: absolute;
  height: 100%;
  background-color: inherit;
  left: -18px;
  top: 0px;
  transform: skewX(20deg);
  width: 35px;
}
.assign-2::after {
  content: "";
  position: absolute;
  height: 100%;
  width: 5px;
  background-color: var(--txt-color-2);
  left: 13px;
  top: 0;
  transform: skewX(20deg);
}
/* Assignment 04 */
.assign-4 {
  width: 200px;
  height: 200px;
  background-color: var(--gray-color-4);
  border-bottom: 5px solid var(--black-color-4);
  margin-inline: auto;
  position: relative;
  margin-top: 140px;
}
.assign-4::before {
  content: "Elzero";
  position: absolute;
  bottom: 5px;
  left: 10px;
  font-size: 1.2rem;
  color: var(--txt-color-1);
  font-family: arial;
}
.assign-4::after {
  content: "";
  position: absolute;
  width: 130px;
  height: 130px;
  background-color: var(--black-color-4);
  z-index: 1;
  transform: rotate(45deg);
  border: 5px solid var(--txt-color-1);
  left: 30px;
  top: -70px;
}
/* Assignment 05 */
body {
  perspective: 1000px;
}
.assign-5 {
  width: 200px;
  height: 200px;
  margin-inline: auto;
  position: relative;
  transform-style: preserve-3d;
  transition: transform 1s;
}
.assign-5:hover {
  transform: rotateX(-180deg);
}
.assign-5::after,
.assign-5::before {
  font-family: arial;
  font-size: 30px;
  width: 100%;
  display: block;
  color: var(--txt-color-1);
  height: 100%;
  text-align: center;
  line-height: 200px;
  position: absolute;
  backface-visibility: hidden;
}
.assign-5::before {
  content: "Front";
  background-color: var(--purple-color-5);
}
.assign-5::after {
  content: "Back";
  background-color: var(--blue-color-5);
  transform: rotateX(180deg);
}