.h-center {
    text-align: center;
}

#page-title-container {
    margin-top: 2em;
}

.row-spacer {
    height: 2em;
}

#question, #answer {
    font-size: 3em;
    font-family: monospace;
}

.column-spacer {
    font-size: 1px;
    line-height: 1px;
}

input[type="number"].correct {
    background-color: lightgreen;
    border: 2px solid green;
}

div#response.correct {
    background-color: lightgreen;
    border-radius: 5px;
}

input[type="number"].incorrect {
    background-color: lightcoral;
    border: 2px solid crimson;
}

div#response.incorrect {
    background-color: lightcoral;
    border-radius: 5px;
}

/* Chrome, Safari, Edge, Opera */
input::-webkit-outer-spin-button,
input::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

/* Firefox */
input[type="number"] {
    appearance: textfield;
    -moz-appearance: textfield;
}