style.css

:root {
  --red: rgba(211, 87, 91, 0.81);
  --red-glow: rgba(211, 87, 91, 0.91);
  --red-scanline: rgba(204, 94, 98, 0.2);
  --black-scanline: rgba(1, 1, 1, 0.9);
  --black-hover-background: rgba(0, 0, 0, 0.25);
  --blue: #61e4fa;
  --yellow: #f7f500;
  --text-shadow: rgb(0, 208, 255);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  height: 100%;
  display: block;
  font-family: "GinesoSoft-ConMed";
}

body {
  background-image: url("bg.png");
  background-size: cover;
}

.logo {
  font-family: "Cyberpunk";
  color: var(--yellow);
  text-align: center;
  font-size: 42px;
  text-shadow: var(--text-shadow) 2px 3px 0px;
  line-height: 1.5;
  padding: 25px 0px;
}

.sublogo {
  font-family: "GinesoSoft-ConMed";
  font-size: 24px;
  color: var(--text-shadow);
  text-shadow: none;
  text-align: right;
  letter-spacing: 24px;
  padding-right: 15px;
}

.menu {
  display: inline-block;
  margin-left: 150px;
  width: 400px;
  height: 100%;
  background: repeating-linear-gradient(
      to bottom,
      transparent 0%,
      var(--red-scanline) 1px,
      var(--red-scanline) 3px,
      var(--red-scanline) 5px,
      var(--red-scanline) 4px,
      transparent 0.5%
    ),
    repeating-linear-gradient(
      to left,
      var(--black-scanline) 100%,
      var(--black-scanline) 100%
    );
}

.menu ul {
  list-style-type: none;
  padding: 0px 25px;
}

.menu ul li {
  text-transform: uppercase;
  cursor: pointer;
  /* layout */
  position: relative;
  padding: 10px;
  margin: 15px 0px;
  overflow: hidden;
  width: 350px;
  height: 54.5px;
  clip-path: polygon(350px 0px, 350px 29px, 322px 57px, 0px 57px, 0px 0px);

  /* font */
  color: var(--red);
  font-size: 26px;
  text-shadow: 0px 0px 3px var(--red-glow);

  /* Border */
  border-style: solid;
  border-width: 2px;
  border-color: transparent;
  /* Animation */
  transition: color 1s ease-out;
  transition: border-color 1s ease-out;
}

.menu ul li::after {
  /* Layout */
  content: "";
  position: absolute;
  bottom: -17px;
  right: -17px;
  width: 30px;
  height: 30px;
  transform: rotate(45deg);

  /* Border */
  border-width: 2px;
  border-style: solid;
  border-color: transparent;

  /* Animation */
  transition: color 1s ease-out;
  transition: border-color 1s ease-out;
}

.menu ul li:hover::after,
.menu ul li:hover {
  color: var(--blue);
  background: var(--black-hover-background);
  
  border-color: var(--blue);

  transition: color 0.23s linear;
  transition: border-color 0.23s linear;
}