changedetection.io/changedetectionio/static/styles/scss/parts/_browser-steps.scss

#browser_steps {
  /* convert rows to horizontal cells */
  th {
    display: none;
  }

  li {
    &.browser-step-with-error {
      background-color: #ffd6d6;
      border-radius: 4px;
    }
    &:not(:first-child) {
      &:hover {
        opacity: 1.0;
      }
    }
    list-style: decimal;
    padding: 5px;
    .control {
      padding-left: 5px;
      padding-right: 5px;
      a {
        font-size: 70%;
      }
    }
    &.empty {
      padding: 0px;
      opacity: 0.35;
      .control {
        display: none;
      }
    }
    &:hover {
      background: #eee;
    }
    > label {
      display: none;
    }
  }
}


#browser-steps .flex-wrapper {
  display: flex;
  flex-flow: row;
  height: 70vh;
  font-size: 80%;
  #browser-steps-ui {
    flex-grow: 1;      /* Allow it to grow and fill the available space */
    flex-shrink: 1;    /* Allow it to shrink if needed */
    flex-basis: 0;     /* Start with 0 base width so it stretches as much as possible */
    background-color: #eee;
    border-radius: 5px;

  }

  #browser-steps-fieldlist {
    flex-grow: 0;      /* Don't allow it to grow */
    flex-shrink: 0;    /* Don't allow it to shrink */
    flex-basis: auto;  /* Base width is determined by the content */
    max-width: 400px;  /* Set a max width to prevent overflow */
    padding-left: 1rem;
    overflow-y: scroll;
  }
}

/*  this is duplicate :( */
#browsersteps-selector-wrapper {
  height: 100%;
  width: 100%;
  overflow-y: scroll;
  position: relative;
  //width: 100%;
  > img {
    position: absolute;
    max-width: 100%;
  }

  > canvas {
    position: relative;
    max-width: 100%;

    &:hover {
      cursor: pointer;
    }
  }

  .loader {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    margin-left: -40px;
    z-index: 100;
    max-width: 350px;
    text-align: center;
  }

  /* nice tall skinny one */
  .spinner, .spinner:after {
    width: 80px;
    height: 80px;
    font-size: 3px;
  }

  #browsersteps-click-start {
    &:hover {
      cursor: pointer;
    }
    color: var(--color-grey-400);
  }
}