Add style tags around that part.
<style>
@import url('https://fonts.googleapis.com/css2?family=Martian+Mono&display=swap');
body{
font-family: 'martian mono', cursive;
font-size: 80%;
}
img{
filter: sepia(100%) saturate(0);
}
img:hover{
filter: sepia(100%) saturate(0) blur(1px);
animation: shake 1s;
animation-iteration-count: infinite;
}
@keyframes shake{
0% {transform: translate(1px, 1px) rotate(0deg);}
10% {transform: translate(-1px, -2px) rotate(-1deg);}
20% {transform: translate(-2px, 0px) rotate(1deg);}
30% {transform: translate(2px, 2px) rotate(0deg);}
40% {transform: translate(1px, -1px) rotate(1deg);}
50% {transform: translate(-1px, 2px) rotate(-1deg);}
60% {transform: translate(-2px, 1px) rotate(0deg);}
70% {transform: translate(2px, 1px) rotate(-1deg);}
80% {transform: translate(-1px, -1px) rotate(1deg);}
90% {transform: translate(1px, 2px) rotate(0deg);}
100% {transform: translate(1px, -2px) rotate(-1deg);}
</style>