渐变动态边框

[klren0312]

<div class="block">
  <div class="block-loading">
    <div class="block-loading-block">
      <div class="block-loading-blank">&nbsp;</div>
      <div class="block-loading-inner"></div>
    </div>
  </div>
</div>

body {
  background: #333;
}
.block {
  position: relative;
  width: 675px;
  height: 422px;
}

.block-loading {
      position: absolute;
      left: 0;
      right: 0;
      width: 100%;
      height: 100%;
      border-radius: 5px;
      transform-style: preserve-3d;
    }
    .block-loading-block {
      width: 100%;
      height: 100%;
      transition: 5s cubic-bezier(0.4,0,0.2,1);
      transition-property: color,filter,transform;
      -webkit-appearance: none;
      -moz-appearance: none;
      appearance: none;
      position: relative;
      border: 0;
      font: inherit;
      overflow: hidden;
      margin: calc(5px * 0);
      padding: 5px;
      color: #a1a1aa;
      border-radius: 0.5rem;
      transform: none;
      user-select: none;
      will-change: transform;
      background-color: rgba(255 255 255 0);
      min-width: 8rem;
      box-sizing: border-box;
    }
    .block-loading-blank {
      width: 100%;
      height: 100%;
      display: inline-flex;
      position: relative;
      background-image: linear-gradient(to top right,rgba(1 1 1 0.9),#141414);
      background-color: #141414;
      justify-content: center;
      /* padding: 0.625rem 1rem; */
      text-align: center;
      z-index: 10;
      border-radius: 0.75rem;
    }
    .block-loading-inner {
      position: absolute;
      width: 100%;
      inset: 0;
      height: 100%;
      top: 50%;
      border-radius: 5px;
      transform: translateY(-50%) scaleY(4) scaleX(4);
      will-change: transform;
      z-index: 2;
    }
    .block-loading-inner::before {
      content: '';
      width: 100%;
      position: absolute;
      left: 0;
      min-height: 100%;
      top: 50%;
      aspect-ratio: 1/1;
      transform-origin: center;
      background-image: conic-gradient(#f9dcdd 0deg,#c1a4e8 60deg,transparent 100deg,transparent 130deg,transparent 160deg,#f2efe8 190deg,#b8e2fb 230deg,transparent 270deg);
      opacity: var(1, 0);
      filter: blur(8px);
      animation: AnimationInner 2.5s linear infinite;
      animation-play-state: var(running, paused);
      transition: 5s cubic-bezier(0.4, 0, 0, 2, 1);
      transition-property: opacity;
    }
    @keyframes AnimationInner {
      0% {
        transform: translateY(-50%) rotate(0deg)
      }

      to {
        transform: translateY(-50%) rotate(1turn)
      }
    }

codepen

https://codepen.io/klren0312/pen/vYvWbWj