Overlay is the colored layer that appears on the thumbnails. Usually what darkens the image on mouse over. However, it can appear with any transparency or color, it's up to you. The mouse interaction can control the behavior. It means that the overlay under the mouse may get hidden to reveal the picture. Or the opposite, only apply the overlay when the mouse is over a thumbnail. Of course they can be completely turned off or applied regardless of the mouse.
Another part of the overlay is the little icon. Out of the box it's a Retina ready magnifier glass. You can replace this with your custom transparent PNG. For example: video icon, your company's logo, transparent glass effect or anything else you have in mind.
Overlay behavior on desktop and mobile devices differently.
Opacity and color.
Icon in the middle, built-in magnifier glass or your custom image.
Overlay icon's opacity.
Captions (just a teaser)
Captions are highly customizable to ensure they don't differ from your existing design. Colorize the text or the background behind it. Discover all the possibilities by the different transparency options. This includes a fading gradient background. Captions too strong? Lower the opacity of the entire caption. Or just make the background slightly transparent while the text on it fully opaque. Don't like the background at all? Turn it off. Wish the background matched the width of the title? No problem! Small text, big text? Shadow? Yeah!
Very powerful styling is achieved by three borders and two shadows. When tastefully combined, of course. Polaroid look, subtle edge, frame, colored spacing, tinted shadow... just to get your imagination going. This is a 5-way customization. Each accepts color and size values.