More work on various parts of the multidimensional filter.

Added custom CSS style for formatting the book.

styles/custom.css

@@ -0,0 +1,76 @@
+<style>
+    @font-face {
+        font-family: "Computer Modern";
+        src: url('http://9dbb143991406a7c655e-aa5fcb0a5a4ec34cff238a2d56ca4144.r56.cf5.rackcdn.com/cmunss.otf');
+    }
+    @font-face {
+        font-family: "Computer Modern";
+        font-weight: bold;
+        src: url('http://9dbb143991406a7c655e-aa5fcb0a5a4ec34cff238a2d56ca4144.r56.cf5.rackcdn.com/cmunsx.otf');
+    }
+    @font-face {
+        font-family: "Computer Modern";
+        font-style: oblique;
+        src: url('http://9dbb143991406a7c655e-aa5fcb0a5a4ec34cff238a2d56ca4144.r56.cf5.rackcdn.com/cmunsi.otf');
+    }
+    @font-face {
+        font-family: "Computer Modern";
+        font-weight: bold;
+        font-style: oblique;
+        src: url('http://9dbb143991406a7c655e-aa5fcb0a5a4ec34cff238a2d56ca4144.r56.cf5.rackcdn.com/cmunso.otf');
+    }
+    div.cell{
+        width:800px;
+        margin-left:16% !important;
+        margin-right:auto;
+    }
+    h1 {
+        font-family: Helvetica, serif;
+    }
+    h4{
+        margin-top:12px;
+        margin-bottom: 3px;
+       }
+    div.text_cell_render{
+        font-family: Computer Modern, "Helvetica Neue", Arial, Helvetica, Geneva, sans-serif;
+        line-height: 145%;
+        font-size: 130%;
+        width:800px;
+        margin-left:auto;
+        margin-right:auto;
+    }
+    .CodeMirror{
+            font-family: "Source Code Pro", source-code-pro,Consolas, monospace;
+    }
+    .prompt{
+        display: None;
+    }
+    .text_cell_render h5 {
+        font-weight: 300;
+        font-size: 22pt;
+        color: #4057A1;
+        font-style: italic;
+        margin-bottom: .5em;
+        margin-top: 0.5em;
+        display: block;
+    }
+    
+    .warning{
+        color: rgb( 240, 20, 20 )
+        }  
+</style>
+<script>
+    MathJax.Hub.Config({
+                        TeX: {
+                           extensions: ["AMSmath.js"]
+                           },
+                tex2jax: {
+                    inlineMath: [ ['$','$'], ["\\(","\\)"] ],
+                    displayMath: [ ['$$','$$'], ["\\[","\\]"] ]
+                },
+                displayAlign: 'center', // Change this to 'center' to center equations.
+                "HTML-CSS": {
+                    styles: {'.MathJax_Display': {"margin": 4}}
+                }
+        });
+</script>