LESS Reference Manual— I think there are two mistakes need correction

I think there are two mistakes need correction on the Less manual website.

Please visit Less manual website

I have run the test code such as the following( by webstorm and less 2.6.1)，
I have some questions and would like to share.

the page—— # Language Features

1.Click the left column：Passing Rulesets to Mixins
Look at right column code：
I think it should be after the Number 1200 , need to add "px"
Reads as follows

Here the desktop-and-old-ie mixin defines the media query and root class so that you can use a mixin to wrap a piece of code. This will output

.desktop-and-old-ie(@rules) {
      @media screen and (min-width: 1200) { @rules(); }
      html.lt-ie9 &                       { @rules(); }
}
header {
      background-color: blue;
      .desktop-and-old-ie({
            background-color: red;
      });
}

2.Click the left column：Passing Rulesets to Mixins
Look at right column code：
I think it should be in front of the word "detached-ruleset" to add a symbol "@" .
Reads as follows

Private variables:

detached-ruleset: { 
    @color:blue; // this variable is private
};
.caller {
    color: @color; // syntax error
}

Start at the Less manual website's Language Features section, under “Passing Rulesets to Mixins,” and compare both reported examples with Less 2.6.1 behavior. Correct the two documented syntax issues, then verify that the rendered examples and surrounding explanations are accurate.