A+b and a~b not working !?

#1

What can be the reason ?
Images (Screenshots) :

  1. https://drive.google.com/open?id=13_WfFRj_e4FG_az0xV6AjNrhfadHUIhq
    (html code and output^)

  2. https://drive.google.com/open?id=1XT50jBcxtQXhwaqkpjn6_w92VkTdy6h8
    (css code and output^)

#2

I also used
ul > li {
color:blue;
}
and now:
ol + ul{
color: green;
}

So, it is not overriding in my opinion ? What precedence rules are followed for multi combinators ?

#3

Are you sure you saved the css file, included it in html and refreshed the browser. Asking this because file is not saved in the screenshot.
By the way, css precedence order is:

There are several rules ( applied in this order ) :

  1. inline css ( html style attribute ) overrides css rules in style tag and css file
  2. a more specific selector takes precedence over a less specific one
  3. rules that appear later in the code override earlier rules if both have the same specificity.
  4. A css rule with !important always takes precedence.