To keep the center alignment specifically in the `footer` while removing it from other parts of the CSS, you can add the `text-align: center;` property directly to the `footer` selector. Here's the adjusted CSS:

```css
:root {
    --black: #000;
    --white: #f8f8f8;
    --green: #40ffaf;
    --red: #ff4e4e;
}

html {
    font-family: "Nunito Sans", sans-serif;
    font-weight: 400;
    font-style: normal;
    color: var(--white);
    min-height: 100%;
    background-color: var(--black);
}

body {
    display: flex;
    flex-direction: column;
    flex-wrap: wrap;
    align-content: center;
    min-height: 100vh;
    margin-left: 160px; /* Added left margin */
    margin-right: 160px; /* Added right margin */
}

h1 {
    font-family: "Nunito Sans", sans-serif;
    font-weight: 700;
    font-style: normal;
    text-transform: uppercase;
    letter-spacing: 6px;
    font-size: 4rem;
    color: var(--white);
    max-width: 64rem;
    margin: 80px 0 24px;
}

h2 {
    font-weight: 400;
    font-size: 1.6rem;
    max-width: 56rem;
}

video {
    width: 100vw;
    height: 100vh;
    object-fit: cover;
    position: fixed;
    top: 0;
    left: 0;
    z-index: -1;
    opacity: .1;
}

main {
    display: flex;
    flex-direction: column;
    flex-grow: 1;
    margin: 16px;
    z-index: 1;
    opacity: .88;
}

footer {
    text-align: center; /* Adding center alignment */
    padding: 64px 16px 16px;
    z-index: 1;
    opacity: .88;
}

footer p {
    margin-bottom: 0;
}

footer a {
    color: var(--white);
    text-decoration: none;
    border-bottom: none;
    transition: all .3s ease;
}

footer a:hover {
    color: var(--green);
    border-bottom: var(--red) 1px dotted;
}

@media screen and (max-width: 1024px) { /* Tablets and below */
    body {
        margin-left: 20px; /* Smaller margin for tablet */
        margin-right: 20px; /* Smaller margin for tablet */
    }


    }
}

@media screen and (max-width: 480px) { /* Mobile phones */
    body {
        margin-left: 10px; /* Even smaller margin for mobile */
        margin-right: 10px; /* Even smaller margin for mobile */
    }
@media screen and (max-width: 726px) {
    h1 {
        font-size: 5.2rem;
    }
}

@media screen and (max-width: 480px) {
    h1 {
        font-size: 4rem;
        letter-spacing: 6px;
    }
    
    h2 {
        font-size: 1.4rem;
    }
}
```