think I fixed sunk text problem thx to darobu, u have to modify template.html file, you can find it in the same directory as main.css.
You have to modify alignChat() function as follow:

function alignChat() {
var windowHeight = window.innerHeight;
if (windowHeight > 0) {
var contentElement = document.getElementById('Chat');
var contentHeight = contentElement.offsetHeight + 15;
if (windowHeight - contentHeight > 0) {
contentElement.style.position = 'relative';
contentElement.style.top = (windowHeight - contentHeight) + 'px';
}
else {
contentElement.style.position = 'static';
}
}
scrollToBottom();
}


What I've done is just adding "+15" for the contentHeight.