html, body {
    margin: 0;
    padding: 0;
    overflow: hidden; /* Prevent scrolling */
    -webkit-text-size-adjust: none;
    /* the app's background. Keep in step with ttMediumGrayColor in ttAppColors.js */
    background-color: #969696;
}

/* the caret after a value typed into an answer square, blinking */
.ttCaret {
    display: inline-block;
    height: 0.9em;
    vertical-align: -0.1em;
    background-color: #ee6791; /* ttPinkColor */
    animation: ttCaretBlink 1s step-end infinite;
}

@keyframes ttCaretBlink {
    50% { opacity: 0; }
}