p5.js-web-editor/client/styles/components/_preview-frame.scss

.preview-frame {
  min-height: 100%;
  min-width: 100%;
  position: absolute;
  border-width: 0;
}

.preview-frame-holder {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.preview-frame-overlay {
  height: 100%;
  width: 100%;
  position: absolute;
  z-index: 10;
  display: none;
}

.preview-frame-placeholder {
  width: #{400 / $base-font-size}rem;
  height: #{400 / $base-font-size}rem;
  position: absolute;
  @include themify() {
    background: getThemifyVariable('preview-placeholder-color');
  }
}

.preview-frame__header {
  height: #{29 / $base-font-size}rem;
}

.preview-frame__title {
  @include themify() {
    color: getThemifyVariable('secondary-text-color');
  }
  height: #{29 / $base-font-size}rem;
  padding-top: #{7 / $base-font-size}rem;
  padding-left: #{5 / $base-font-size}rem;
  font-size: #{12 / $base-font-size}rem;
  font-weight: normal;
}

.preview-frame__content {
  position: relative;
  flex: 1 1 0;
}