body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #f5f5f5;
}

div.sign_in_box {
    display: flex;
    flex-direction: column;
    background-color: #f2f1f1;
    width: 25em;
    border-radius: 8px;
    box-shadow: 0 4px 8px #b9cfb967;
    overflow: hidden;
}

h1.h1_sign_in {
    background-color: #384544;
    font-size: 1.75em;
    color: #f2f1f1;
    text-align: center;
    padding: 0.8em 0;
    margin: 0;
}

form.sign_in {
    display: flex;
    flex-direction: column;
    padding: 2em;
    flex-grow: 1;
}

.username {
    padding: 0.7em 0.5em 0 0.5em;
}

.password {
    padding: 0.5em;
}

input {
    padding: 0.5em;
    border: 1px solid #b9cfb9;
    border-radius: 4px;
    font-size: 1em;
}

.div_signin {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100%;
    width: 100%;
}

button.sign_in_button {
    padding: 0.75em;
    background-color: #384544;
    color: #f2f1f1;
    border: none;
    font-size: 1em;
    border-radius: 0.3em;
    cursor: pointer;
}

button.sign_in_button {
    padding: 0.75em;
    background-color: #384544;
    color: #f2f1f1;
    border: none;
    font-size: 1em;
    border-radius: 0.3em;
    cursor: pointer;
}

button.sign_in_button:hover {
    background-color: #273433;
}

.sign_in_a {
    padding: 0.7em 1em 0.8em 1em;
    text-align: center;
    color: #384544;
    text-decoration: none;
    display: block;
}

.sign_in_a:hover {
    text-decoration: underline;
}

@media (max-width: 575.98px) {
    div.sign_in_box {
        width: 20em;
    }

    h1.h1_sign_in {
        font-size: 1.3em;
    }

    input {
        font-size: 0.8em;
    }

    button.sign_in_button {
        padding: 0.5em;
    }
}

@media (max-width: 340.98px) {
    div.sign_in_box {
        width: 15em;
    }

    h1.h1_sign_in {
        font-size: 1em;
    }

    input {
        font-size: 0.55em;
    }

    button.sign_in_button {
        padding: 0.4em;
    }

}