use this to fix images and videos

/*everything fixing photos/videos related*/

.post img.main_photo {
max-width:100%;
}

.post img {
max-width:100%;
height:auto;
}

.post .photo img {
opacity:1;
-webkit-transition:all 0.5s ease;
-moz-transition:all 0.5s ease;
-o-transition:all 0.5s ease;
transition:all 0.5s ease;
line-height:0;
}

.tumblr_post.photo p {
display:none;
}

.post .photoset {
}


.video {
margin:6px 0 8px 0;
}

.post video.main_video {
width:100%;
}

.post video {
width:100%;
height:auto;
}

.post .video video {
opacity:1;
-webkit-transition:all 0.5s ease;
-moz-transition:all 0.5s ease;
-o-transition:all 0.5s ease;
transition:all 0.5s ease;
line-height:0;
}

.tumblr_post.video p {
display: none;
}

/*end of fixing photos/videos-vangelion*/