title: Changing color of all headers in pdf output by RMarkdown
body: <p>I want to change the colour of all the headers in the pdf document created by Rmarkdown. The headers are not properly visible in the black. I am changing the fonts and sizes by this code in latex. </p>
  
  <pre><code>---
  title: "PBMC proliferation assay"
  author: "Koundinya Desiraju"
  output:
    pdf_document:
      highlight: tango
      keep_tex: yes
      number_sections: yes
      toc: yes
  ---
  
  
  \fontsize{14}{20}
  \selectfont
  </code></pre>
  
  <p>Is there a way i can do this with a script like this? My knowledge of latex is zero. so,please help me. Basically I want all headings specified by # or ## in RMarkdown to be in different color in pdf.</p>