You only need to consider one image which is the bottom part of your mask then use a simple gradient for the other part. You also don’t need mask-composite
. Simply adjust the size/position so that both mask don’t overlap:
.img-poster {
display: block;
max-width: 100%;
-webkit-mask:
linear-gradient(#fff,#fff) top,
url(https://i.ibb.co/5WvbqgG/zmylJ.png) bottom;
-webkit-mask-size:
100% calc(100% - 30px),
auto 30px;
-webkit-mask-repeat: repeat-x;
mask:
linear-gradient(#fff,#fff) top,
url(https://i.ibb.co/5WvbqgG/zmylJ.png) bottom;
mask-size:
100% calc(100% - 30px),
auto 30px;
mask-repeat: repeat-x;
}
<section class="section poster-container">
<img src="https://imagejournal.org/wp-content/uploads/bb-plugin/cache/23466317216_b99485ba14_o-panorama.jpg" alt="" class="img-poster add img-responsive">
</section>