 string
           * @default ''
           */
          linehighlight: {
            type: String,
            value: ''
          },
          /**
           * The `theme` attribute specifies the name of a valid Prism theme
           * to use from the selection of themes available in the official Prism
           * [package](https://github.com/LeaVerou/prism/tree/gh-pages/themes). The
           * 'prism-' portion of the theme filename is automatically prepended for
           * you. To set the theme to 