style.css

* {
    margin: 0;
    padding: 0;
    border: none;
    outline: none;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

html,
body {
    height: 100%;
}

body {
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: sans-serif;
    background: #040404;
}

label {
    position: relative;
}

label input {
    font-family: sans-serif;
    font-size: 1.2rem;
    color: #f9f9f9;
    background: transparent;
    padding: 1rem 3.2rem 1rem 1.2rem;
    min-width: 24rem;
    border-radius: 0.2rem;
    border: 2px solid #7a7a7a56;
    transition: border-color 0.2s;
}

label input:focus {
    border-color: #2aa6ee;
}

label p {
    color: #f9f9f9;
    font-size: 1.2rem;
    user-select: none;
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    margin-left: 0.8rem;
    padding: 0 0.4rem;
    background: #040404;
    transition: top 0.2s, font-size 0.2s, color 0.2s;
}

label input:focus+p,
label input:not(:placeholder-shown)+p {
    top: 0;
    font-size: 1rem;
    color: #2aa6ee;
}

label input:not(:focus)+p {
    color: #7a7a7a56;
}