add overview and categorical description to the first page

Author: dr-orlovsky

content/_index.md

@@ -10,7 +10,7 @@ and uses statical and strong generalized algebraic data types known as [strict t
 The language design and compiler is a work in progress. The compiler will compile the code into LLVM and [AluVM](AluVM)
 targets, and a special cross-compiler from Cation to Rust will be available.
 
-## Language Features
+# Features
 
 1. ![Applied Category Theory](/symbols/act.svg)
    The (first) categorical programming language with notations close to mathematics
@@ -19,14 +19,28 @@ targets, and a special cross-compiler from Cation to Rust will be available.
 3. ![Fun to program](/symbols/fun.svg)
    Easy to read and fun to program, avoid visual clutter and boilerplate
 
-<div></div>
+# Learn more
+
+Learn cation from docs, examples or language reference. 
+
+- ## Language Overview
+
+  Check the language features and get a first impression of the language.
+
+  <a href="/overview" class="button">Language overview</a>
 
 - ## Language Design
 
   Read more on language design in the documentation.
 
   <a href="/design" class="button">Language design docs</a>
 
+- ## Category Theory
+
+  Understand the language in the terms of Category Theory.
+
+  <a href="/category" class="button">Categorical explanation</a>
+
 - ## Language Reference
 
   Reference contains a list of Cation keywords and statements.
@@ -39,6 +53,12 @@ targets, and a special cross-compiler from Cation to Rust will be available.
 
   <a href="/examples" class="button">Code examples</a>
 
+- ## Try Yourself
+
+  See the language in action by trying to compile the code.
+
+  <a href="/try" class="button">Cation compiler</a>
+
 ---
 
 Cation is a work in progress project. Its development is lead by [Dr Maxim Orlovsky][orlovsky] at [UBIDECO Labs],

templates/base.html

@@ -36,13 +36,15 @@
   </ol>
 
   <ul>
+    <li><a href="/overview">Overview</a></li>
+    <li class="div">|</li>
     <li><a href="/design">Design</a></li>
     <li class="div">|</li>
     <li><a href="/reference">Reference</a></li>
     <li class="div">|</li>
     <li><a href="/examples">Examples</a></li>
-    <li class="div">|</li>
-    <li><a href="/try">Try</a></li>
+    <!-- li class="div">|</li>
+    <li><a href="/try">Try</a></li -->
     <!-- li class="div">|</li>
     <li><a href="/community">Community</a></li -->
   </ul>