React Form Validation & Handling

index.css

:root {
    font-family: Inter, Avenir, Helvetica, Arial, sans-serif;
    font-size: 16px;
    line-height: 24px;
    font-weight: 400;

    color-scheme: light dark;
    color: rgba(255, 255, 255, 0.87);
    background-color: #242424;

    font-synthesis: none;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    -webkit-text-size-adjust: 100%;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background-color: #ffffff;
    background-image: radial-gradient(#444cf7 0.5px, #e5e5f7 0.5px);
    background-size: 10px 10px;
}

#root {
    width: 100%;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

form {
    width: 500px;
    padding: 25px;
    background: white;
    border-radius: 12px;
    box-shadow: 10px 10px 5px 0px rgba(0, 0, 0, 0.05);
    -webkit-box-shadow: 10px 10px 5px 0px rgba(0, 0, 0, 0.05);
    -moz-box-shadow: 10px 10px 5px 0px rgba(0, 0, 0, 0.05);
}

.button {
    appearance: none;
    background-color: #000000;
    border: 2px solid #1a1a1a;
    border-radius: 8px;
    box-sizing: border-box;
    color: #ffffff;
    cursor: pointer;
    display: inline-block;
    font-family: Roobert, -apple-system, BlinkMacSystemFont, "Segoe UI",
        Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji",
        "Segoe UI Symbol";
    font-size: 16px;
    font-weight: 600;
    line-height: normal;
    margin: 0;
    margin-top: 20px;
    min-height: 40px;
    min-width: 0;
    outline: none;
    padding: 16px 24px;
    text-align: center;
    text-decoration: none;
    transition: all 300ms cubic-bezier(0.23, 1, 0.32, 1);
    user-select: none;
    -webkit-user-select: none;
    touch-action: manipulation;
    width: 100%;
    will-change: transform;
}

.button:disabled {
    pointer-events: none;
}

.button:hover {
    box-shadow: rgba(0, 0, 0, 0.25) 0 8px 15px;
    transform: translateY(-2px);
}

.button:active {
    box-shadow: none;
    transform: translateY(0);
}

::placeholder {
    color: black;
    opacity: 0.5;
}

style.css

.inputField {
    width: 100%;
    display: flex;
    flex-direction: column;
    margin-bottom: 10px;
}

.inputField label {
    color: black;
    min-width: 150px;
}

.inputField span {
    font-size: 14px;
}

.inputField input {
    background: transparent;
    outline: 0;
    border: 1px solid rgba(0, 0, 0, 0.25);
    height: 55px;
    border-radius: 8px;
    padding: 0 10px;
    color: black;
    font-size: 16px;
}