[css-values-3] Make heading capitalization consistent.

Author: fantasai

css-values-3/Overview.bs

@@ -82,7 +82,7 @@ Value Definition Syntax</h2>
 	A value so described can have one or more components.
 
 <h3 id="component-types">
-Component value types</h3>
+Component Value Types</h3>
 
 	Component value types are designated in several ways:
 
@@ -182,7 +182,7 @@ Component value types</h3>
 	''background: url(corner.png) no-repeat, inherit;'' is invalid.
 
 <h3 id="component-combinators">
-Component value combinators</h3>
+Component Value Combinators</h3>
 
 	Component values can be arranged into property values as follows:
 
@@ -218,7 +218,7 @@ Component value combinators</h3>
 	</pre>
 
 <h3 id="component-multipliers">
-Component value multipliers</h3>
+Component Value Multipliers</h3>
 
 	Every type, keyword, or bracketed group may be followed by one of
 	the following modifiers:
@@ -299,7 +299,7 @@ Combinator and Multiplier Patterns</h3>
 	while the "in order" possibilities are all variants on juxtaposition.
 
 <h3 id="component-whitespace">
-Component values and white space</h3>
+Component Values and White Space</h3>
 
 	Unless otherwise specified,
 	<a href="https://www.w3.org/TR/css-syntax/#whitespace">white space</a> and/or comments may appear before, after, and/or between
@@ -316,7 +316,7 @@ Component values and white space</h3>
 	to get this parsed as the two lengths ''1em'' and ''2em''.
 
 <h3 id="value-examples">
-Property value examples</h3>
+Property Value Examples</h3>
 
 	Below are some examples of properties with their corresponding value
 	definition fields
@@ -937,7 +937,7 @@ Distance Units: the <<length>> type</h2>
 	There are two types of length units: <a lt="relative length">relative</a> and <a lt="absolute length">absolute</a>.
 
 <h3 id="relative-lengths">
-Relative lengths</h3>
+Relative Lengths</h3>
 
 	<dfn lt="relative length">Relative length units</dfn> specify a length relative to another length.
 	Style sheets that use relative units can more easily scale from one output environment to another.
@@ -983,7 +983,7 @@ Relative lengths</h3>
 -->
 
 <h4 id="font-relative-lengths">
-Font-relative lengths: the ''em'', ''ex'', ''ch'', ''rem'' units</h4>
+Font-relative Lengths: the ''em'', ''ex'', ''ch'', ''rem'' units</h4>
 
 	The <dfn export id="font-relative-length">font-relative lengths</dfn> refer to the font metrics of the element on which they are used--
 	or, in the case of ''rem'', the metrics of the root element).
@@ -1067,7 +1067,7 @@ Font-relative lengths: the ''em'', ''ex'', ''ch'', ''rem'' units</h4>
 -->
 
 <h4 id="viewport-relative-lengths">
-Viewport-percentage lengths: the ''vw'', ''vh'', ''vmin'', ''vmax'' units</h4>
+Viewport-percentage Lengths: the ''vw'', ''vh'', ''vmin'', ''vmax'' units</h4>
 
 	The <dfn export>viewport-percentage lengths</dfn> are relative to the size of the
 	<a href="https://www.w3.org/TR/CSS21/visudet.html#containing-block-details">initial containing block</a>.
@@ -1115,7 +1115,7 @@ Viewport-percentage lengths: the ''vw'', ''vh'', ''vmin'', ''vmax'' units</h4>
 -->
 
 <h3 id="absolute-lengths">
-Absolute lengths: the ''cm'', ''mm'', ''Q'', ''in'', ''pt'', ''pc'', ''px'' units</h3>
+Absolute Lengths: the ''cm'', ''mm'', ''Q'', ''in'', ''pt'', ''pc'', ''px'' units</h3>
 
 	The <dfn lt="absolute length">absolute length units</dfn> are fixed in relation to each other
 	and [=anchored=] to some physical measurement.