If mobile, press on actual video and drag to upper left corner until you reach the lower right corner.  then tap the full screen icon (video here) 

{"items":["5ef7a6fa47bfb300177ce709"],"styles":{"galleryType":"Columns","groupSize":1,"showArrows":true,"cubeImages":true,"cubeType":"fill","cubeRatio":1.3333333333333333,"isVertical":true,"gallerySize":940,"collageAmount":0,"collageDensity":0,"groupTypes":"1","oneRow":false,"imageMargin":16,"galleryMargin":0,"floatingImages":0,"chooseBestGroup":true,"smartCrop":false,"hasThumbnails":false,"enableScroll":true,"isGrid":true,"isSlider":false,"isColumns":false,"isSlideshow":false,"cropOnlyFill":false,"fixedColumns":1,"enableInfiniteScroll":true,"isRTL":false,"minItemSize":50,"rotatingGroupTypes":"","rotatingCubeRatio":"","gallerySliderImageRatio":1.7777777777777777,"numberOfImagesPerRow":1,"numberOfImagesPerCol":1,"groupsPerStrip":0,"borderRadius":0,"boxShadow":0,"gridStyle":1,"mobilePanorama":false,"placeGroupsLtr":false,"viewMode":"preview","thumbnailSpacings":4,"galleryThumbnailsAlignment":"bottom","isMasonry":false,"isAutoSlideshow":false,"slideshowLoop":false,"autoSlideshowInterval":4,"useCustomButton":false,"bottomInfoHeight":0,"titlePlacement":"SHOW_ON_THE_RIGHT","galleryHorizontalAlign":"center","galleryTextAlign":"center","galleryVerticalAlign":"center","scrollSnap":false,"itemClick":"expand","fullscreen":true,"allowSocial":true,"allowDownload":false,"allowTitle":true,"allowDescription":false,"loveButton":true,"loveCounter":false,"videoPlay":"hover","scrollAnimation":"NO_EFFECT","scrollDirection":0,"overlayAnimation":"FADE_IN","arrowsPosition":0,"arrowsSize":23,"watermarkOpacity":40,"watermarkSize":40,"useWatermark":true,"watermarkDock":{"top":"auto","left":"auto","right":0,"bottom":0,"transform":"translate3d(0,0,0)"},"loadMoreAmount":"all","defaultShowInfoExpand":1,"allowTitleExpand":true,"allowDescriptionExpand":true,"allowLinkExpand":true,"expandInfoPosition":0,"allowFullscreenExpand":true,"fullscreenLoop":false,"galleryAlignExpand":"left","addToCartBorderWidth":1,"addToCartButtonText":"","slideshowInfoSize":200,"playButtonForAutoSlideShow":false,"allowSlideshowCounter":false,"hoveringBehaviour":"NEVER_SHOW","thumbnailSize":120,"magicLayoutSeed":1,"imageHoverAnimation":"NO_EFFECT","calculateTextBoxHeightMode":"AUTOMATIC","calculateTextBoxWidthMode":"PERCENT","textBoxHeight":0,"textBoxWidth":200,"textBoxWidthPercent":50,"textImageSpace":10,"textBoxBorderRadius":0,"textBoxBorderWidth":0,"textsVerticalPadding":0,"textsHorizontalPadding":-30,"titleDescriptionSpace":6,"customButtonText":"","customButtonBorderWidth":1,"customButtonBorderRadius":0,"loadMoreButtonText":"","loadMoreButtonBorderWidth":1,"loadMoreButtonBorderRadius":0,"imageInfoType":"ATTACHED_BACKGROUND","itemBorderWidth":1,"itemBorderRadius":0,"itemEnableShadow":false,"itemShadowBlur":20,"itemShadowDirection":135,"itemShadowSize":10,"imageLoadingMode":"BLUR","expandAnimation":"NO_EFFECT","imageQuality":90,"usmToggle":false,"usm_a":0,"usm_r":0,"usm_t":0,"videoSound":false,"videoSpeed":"1","videoLoop":true,"gallerySizeType":"px","gallerySizePx":940,"itemBorderColor":{"themeName":"color_12","value":"rgba(230,230,230,1)"},"galleryLayout":2,"modifiedGallerySize":true,"selectedLayout":"2|bottom|1|fill|true|0|true","layoutsVersion":2,"selectedLayoutV2":2,"isSlideshowFont":false,"externalInfoHeight":0,"externalInfoWidth":0.5},"container":{"width":940,"galleryWidth":972,"galleryHeight":1440,"scrollBase":0,"height":null}}