index.css

@import url(//fonts.googleapis.com/css?family=Vibur);
@import url("https://fonts.googleapis.com/css2?family=Bungee+Outline&display=swap");

/** 
 *
 *   CSS RESET START
 *
 */

html,
body,
div,
span,
applet,
object,
iframe,
h1,
h2,
h3,
h4,
h5,
h6,
p,
blockquote,
pre,
a,
abbr,
acronym,
address,
big,
cite,
code,
del,
dfn,
em,
img,
ins,
kbd,
q,
s,
samp,
small,
strike,
strong,
sub,
sup,
tt,
var,
b,
u,
i,
center,
dl,
dt,
dd,
ol,
ul,
li,
fieldset,
form,
label,
legend,
table,
caption,
tbody,
tfoot,
thead,
tr,
th,
td,
article,
aside,
canvas,
details,
embed,
figure,
figcaption,
footer,
header,
hgroup,
menu,
nav,
output,
ruby,
section,
summary,
time,
mark,
audio,
video {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 100%;
  vertical-align: baseline;
}
/* HTML5 display-role reset for older browsers */
article,
aside,
details,
figcaption,
figure,
footer,
header,
hgroup,
menu,
nav,
section {
  display: block;
}
body {
  line-height: 1;
}
ol,
ul {
  list-style: none;
}
blockquote,
q {
  quotes: none;
}
blockquote:before,
blockquote:after,
q:before,
q:after {
  content: "";
  content: none;
}
table {
  border-collapse: collapse;
  border-spacing: 0;
}

/** 
  *
  *   CSS RESET END
  *
  */

body {
  margin: 0;
  font-family: "Nunito Sans", sans-serif, -apple-system, BlinkMacSystemFont,
    "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans",
    "Droid Sans", "Helvetica Neue", sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

* {
  box-sizing: border-box;
}

code {
  font-family: source-code-pro, Menlo, Monaco, Consolas, "Courier New",
    monospace;
}

:root {
  background-image: url("assets/neon-background.jpg");
  background-repeat: no-repeat;
  object-fit: cover;
  display: flex;
  flex-direction: column;
  align-items: center;
  box-shadow: inset 0 0 200px 100px rgba(0, 0, 0, 0.5);
  cursor: url("assets/eye_cursor.png"), auto !important;
}

#container {
  display: flex;
  flex-direction: column;
  padding: 20px;
  max-width: 1064px;
  height: 100vh;
}

.kh-logo {
  height: 40px;
}

.cta-button {
  transition: background-color ease-in-out 0.2s;
  border: 2px solid #ff1783;
  color: #ff1783;
  padding: 10px 20px;
  text-align: center;
  text-decoration: none;
  display: inline-block;
  font-weight: 600;
  width: 60%;
  font-size: 16px;
  margin: 4px 2px;
  cursor: pointer;
  background-color: transparent;
  border-radius: 20px;
  box-shadow: 0 8px 16px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
  margin-right: 15px;
}

.cta-button:hover {
  background-color: #ff1783;
  color: white;
}

#copy-404 {
  display: flex;
  flex-direction: column;
  flex: 4;
  text-align: center;
}

#copy-404 h1 {
  font-weight: 900;
  font-size: 2em;
}

#copy-404 h3 {
  margin: 20px 0;
  font-size: 1em;
  font-weight: 600;
}

#main-section {
  color: white;
  flex: 1;
  align-items: center;
  display: flex;
  flex-wrap: wrap;
}

#sign-404 {
  width: 100%;
  text-align: center;
  flex: 6;
  padding-bottom: 80px;
}

#text-404 {
  font-size: 100px;
  font-weight: 900;
  font-family: "Bungee Outline";
  text-shadow: 0 -40px 100px, 0 0 2px, 0 0 1em #ff1783, 0 0 0.5em #ff1783,
    0 0 0.1em #ff1783, 5px 10px 3px #000;
}

#text-404 span {
  transition: text-shadow cubic-bezier(0.075, 0.82, 0.165, 1) 0.4s;
}

#text-404 span:hover {
  color: rgb(27, 27, 27);
  text-shadow: none;
}

.sub-logo {
  text-align: center;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  user-select: none;
}

.sub-logo b {
  font: 400 30px "Vibur";
  color: #fee;
  text-shadow: 0 -40px 100px, 0 0 2px, 0 0 1em #1fff17, 0 0 0.5em #1fff17,
    0 0 0.1em #1fff17, 0 10px 3px #000;
}

.sub-logo b span {
  animation: blink linear infinite 2s;
}
.sub-logo b span:nth-of-type(2) {
  animation: blink linear infinite 3s;
}
@keyframes blink {
  78% {
    color: inherit;
    text-shadow: inherit;
  }
  79% {
    color: #333;
  }
  80% {
    text-shadow: none;
  }
  81% {
    color: inherit;
    text-shadow: inherit;
  }
  82% {
    color: #333;
    text-shadow: none;
  }
  83% {
    color: inherit;
    text-shadow: inherit;
  }
  92% {
    color: #333;
    text-shadow: none;
  }
  92.5% {
    color: inherit;
    text-shadow: inherit;
  }
}

@media only screen and (min-width: 700px) {
  #text-404 {
    font-size: 230px;
    text-shadow: 0 -40px 100px, 0 0 2px, 0 0 1em #ff1783, 0 0 0.5em #ff1783,
      0 0 0.1em #ff1783, 5px 20px 3px #000;
  }

  #copy-404 {
    text-align: left;
    padding-bottom: 80px;
  }

  #copy-404 h1 {
    font-size: 3.5em;
  }

  #copy-404 h3 {
    margin: 45px 0;
    font-size: 1.2em;
  }

  #container {
    padding: 50px 20px;
  }

  .cta-button {
    width: auto;
  }

  .sub-logo b {
    font-size: 50px;
  }
}