This is what you'll use for style sheets. Place each variable on all respective elements:
:root [this is an ultra-specific selector] {
--red: #FF0120;
--first: blue;
--header-size: 4rem;
--body-size: 24px;
}
h1 {
color: var(--red);
font-size: var(--header-size);
}
p {
font-size: var(body-size);
color: var(--first);
}
.block {
display: flex;
padding-left: 20vw;
padding-top: 10vh;
padding-right: 20vw;
}