styles.css

body {
    margin: 0px;
    height: 100vh;
}

#container {
    display: flex;
    margin: 0%;
    background-color: seagreen;
    height: 100%;
}

#img {
    width: min(960px, 40%);
    flex: 1 0 auto;
}

#img img {
    border: solid 1px yellow;
    border-radius: 1%;
    width: min(580px, 100%);
    height: auto;
}

#img figcaption {
    padding: 4px;
    width: fit-content;
}

#img figcaption:hover {
    background-color: violet;
}

div#form {
    background-color: white;
    padding: 20px;
    padding-left: max(20px, 5%);
    display: flex;
    flex-direction: column;
}

#form form {
    border: solid 1px lightgray;
    margin: 3%;
    background-color: azure;
    padding: 10px;
    border-radius: 2%;
}

#form-container {
    height: fit-content;
}

.bold {
    padding: 10px 5px 5px;
    font-size: 30px;
    font-weight: bold;
}

form div {
    margin: 3%;
    display: flex;
    flex-direction: column;
    font-size: large;
}

form input {
    font-size: large;
    width: 60%;
}

form input:focus {
    border: 2px solid dodgerblue;
    box-shadow: aquamarine;
}

#submit {
    width: 20%;
}

#submit button {
    font-size: large;
    padding: 10px 20px;
    border: transparent 0px;
    background-color: forestgreen;
    color: azure;
}

#submit button:hover {
    background-color: lightgray;
    color: black;
}

#sign-in {
    margin-left: 3%;
    padding-left: 20px;
    font-size: medium;
}

input#pw:not(:placeholder-shown):invalid, 
input#pw-cnfrm:not(:placeholder-shown):invalid {
    border: solid 2px red;
}