2c:I[605500,["/_next/static/chunks/106c5b2eb672d60f.js","/_next/static/chunks/0ba991d8f2335c9b.js","/_next/static/chunks/e0fd39e0ec7bdaa8.js","/_next/static/chunks/5b4436cde5f39451.js","/_next/static/chunks/3acb3dbd2ef6aac4.js","/_next/static/chunks/e182bf706c7a3ad0.js","/_next/static/chunks/6b5399a90acd5867.js","/_next/static/chunks/c5dc0dc3bbf72666.js","/_next/static/chunks/863f4f67a2f42ac2.js","/_next/static/chunks/382505bb0e481010.js","/_next/static/chunks/c59fd1f5b1287f3b.js","/_next/static/chunks/48f68b8af61ab8b2.js","/_next/static/chunks/da27d0d9b0f97bf3.js"],"Image"] 2d:I[817164,["/_next/static/chunks/106c5b2eb672d60f.js","/_next/static/chunks/0ba991d8f2335c9b.js","/_next/static/chunks/e0fd39e0ec7bdaa8.js","/_next/static/chunks/5b4436cde5f39451.js","/_next/static/chunks/3acb3dbd2ef6aac4.js","/_next/static/chunks/e182bf706c7a3ad0.js","/_next/static/chunks/6b5399a90acd5867.js","/_next/static/chunks/c5dc0dc3bbf72666.js","/_next/static/chunks/863f4f67a2f42ac2.js","/_next/static/chunks/382505bb0e481010.js","/_next/static/chunks/c59fd1f5b1287f3b.js","/_next/static/chunks/48f68b8af61ab8b2.js","/_next/static/chunks/da27d0d9b0f97bf3.js"],"TipTapContent"] 2e:T51c,

Desktop + Mobile

/**
* Full Width Block
**/
#block-id {
  padding: 17px 0px;
  width: 100vw;
  position: relative;
  left: 50%;
  right: 50%;
  margin-left: -50vw;
  margin-right: -50vw;

  .sqs-block-content{
    max-width:1250px;
    margin:auto;
  }
}

Mobile Only

/**
* Full Width Block
**/
@media(max-width:767px){
  #block-id {
    padding: 17px 0px;
    width: 100vw;
    position: relative;
    left: 50%;
    right: 50%;
    margin-left: -50vw;
    margin-right: -50vw;

    .sqs-block-content{
      max-width:1250px;
      margin:auto;
    }
  }
}

References: Ahmad Shadeed, CSS Tricks

Full Width Image & Video Blocks in Squarespace

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