Exclude default CSS if the styles configuration is set

[vimtaai]

Hi!
It would be nice to disable the default CSS if I'm using my own custom CSS with the markdown-pdf.styles option as the default one can interfere with custom styling.

All you have to do is to make the inclusion of the default CSS dependent of the number of defined custom styles. (Basically move lines 430 and 431 to the else branch of the if on line 435 in extension.js)

vscode-markdown-pdf/extension.js

Line 430 in ff211ed

filename = path.join(__dirname, 'styles', 'markdown.css');

Proposed code snippet (extension.js)

  // 1. read the style of the markdown.styles setting.
  styles = vscode.workspace.getConfiguration('markdown')['styles'];
  if (styles && Array.isArray(styles) && styles.length > 0) {
    for (i = 0; i < styles.length; i++) {
      var href = filename = styles[i];
      var protocol = url.parse(href).protocol;
      if (protocol === 'http:' || protocol === 'https:') {
        style += '<link rel=\"stylesheet\" href=\"" + href + "\" type=\"text/css\">';
      } else if (protocol === 'file:') {
        style += makeCss(filename);
      }
    }
  } else {
    // 2. read the style of the vscode.
    filename = path.join(__dirname, 'styles', 'markdown.css');
    style += makeCss(filename);
  }

Another option would be to include a markdown-pdf.useDefaultStyle setting.

[vimtaai]

I actually see that I only referenced half of the code that needs to be changed so I created a new pull request #50 to solve this issue.