upgradeStyle.css

*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    border: none;
}

body {
    color: #fff;
    background-color: #000;
    font-family: 'Roboto Mono', monospace;
    scroll-behavior: smooth;
    transition: all .5s;
}

a {
    outline: none;
    text-decoration: none;
}

main {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding-bottom: 5rem;
}

.top-container {
    margin: 2rem 0;
}

.top-container a {
    display: flex;
    justify-content: flex-start;
    align-items: center;
    width: fit-content;
    color: #5a51fe;
}

.top-container img {
    width: 40px;
    margin-right: .5rem;
}

.bottom-container {
    background-color: #000;
    border: 1px solid rgba(128, 128, 128, 0.224);
    padding: 2rem;
    padding-right: 15rem;
    box-shadow: 0px 0px 50px 1px rgba(128, 128, 128, 0.189);
    display: flex;
    flex-direction: column;
    gap: 1rem;
    font-family: sans-serif;
    transition: all .5s;
}

.bottom-container h1 {
    font-weight: 700;
}

.bottom-container > p {
    color: rgba(128, 128, 128, 0.868);
    font-size: 1.25rem;
    letter-spacing: .5px;
    font-weight: 100;
    margin: .5rem 0;
}

.bottom-container .features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: .5rem;
    flex-wrap: wrap;
}

.bottom-container .feature {
    width: fit-content;
    padding: 5px 10px;
    background-color: rgba(2, 96, 2, 0.418);
    border-radius: 20px;
    color: rgba(156, 234, 156, 0.626);
    font-size: .95rem;
}

.bottom-container .feature i {
    color: rgb(91, 132, 91);
    font-size: .85rem;
}

.bottom-container form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-top: 1rem;
}

.bottom-container input[type="text"] {
    width: 100%;
    padding: .75rem;
    font-size: 1rem;
    border: 1px solid rgba(128, 128, 128, 0.379);
    border-radius: 3px;
    background-color: #000;
    color: #fff;
    transition: all .5s;
}

.bottom-container input[type="submit"] {
    background: linear-gradient(65deg, #5a51fe, #8751fe);
    color: #fff;
    width: fit-content;
    padding: .75rem 4rem;
    font-size: 1rem;
    text-transform: uppercase;
    border-radius: 3px;
    cursor: pointer;
    box-shadow: 0px 1px 1px 1px rgba(128, 128, 128, 0.372);
    transition: all .5s;
}

.bottom-container input[type="submit"]:hover {
    box-shadow: 0px 5px 15px 1px rgba(128, 128, 128, 0.493);
}

.bottom-container label {
    color: rgba(128, 128, 128, 0.868);
}

::placeholder {
    color: rgba(128, 128, 128, 0.452);
}

.bottom-container input {
    margin: 5px 0;
}

.bottom-container .extras div {
    display: grid;
    grid-template-columns: 20px 1fr;
    margin-bottom: .5rem;
    color: rgba(134, 126, 126, 0.868);
}


.theme-btn {
    font-size: 1.5rem;
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #000;
    height: 50px;
    width: 50px;
    border-radius: 50%;
    cursor: pointer;
    position: fixed;
    right: 1rem;
    bottom: 1rem;
    border: 0;
    outline: 0; 
    transition: all .5s;
}

.theme-btn.light {
    background-color: #fff;
}

body.light  {
    background-color: #fff;
    color: #000;
}

body.light .theme-btn i {
    filter: invert(1);
}

body.light .bottom-container {
    background-color: #fff;
    border: 1px solid rgba(174, 172, 172, 0.589);
}

body.light .bottom-container .feature {
    background-color: rgba(125, 242, 125, 0.418);
    color: rgb(5, 67, 3);
}

body.light .bottom-container input[type="text"] {
    color: #000;
    background-color: #fff;
}

body.light .bottom-container .extras div {
    color: rgb(64, 62, 62);
}

    

@media (max-width: 720px) {
    .bottom-container .features {
        grid-template-columns: 1fr;
    }
}