diff --git a/html/style.css b/html/style.css
new file mode 100644
index 0000000..f864694
--- /dev/null
+++ b/html/style.css
@@ -0,0 +1,84 @@
+html {
+     font-size: 20px;
+     font-family: "Charter","Georgia",'Times New Roman',serif;
+}
+ body {
+     line-height: 1.3;
+}
+ article, .container {
+     max-width: 800px;
+     margin: auto;
+}
+ h1,h2,h3,h4 {
+     font-family: arial, sans;
+}
+ h2 {
+     text-align: center;
+     margin-bottom: 1em;
+}
+ h3 {
+     font-family: arial, sans;
+     margin: 1.3em 0 0.9em;
+}
+ b {
+     font-family: arial, sans;
+     font-weight: normal;
+     font-size: 0.8em;
+}
+ pre, p {
+     margin: 0.9em 0px 0.9em;
+}
+ pre, code {
+     background-color: #eeeeff;
+     line-height: normal;
+     overflow: auto;
+     font-size: 0.8em;
+}
+ pre {
+     padding: 0.5em 0.5em;
+     border-radius: 4px;
+}
+ .nav ul {
+     padding-left: 0;
+     border-radius: 4px;
+     list-style: none;
+     display: flex;
+     flex-direction: row;
+     flex-wrap: nowrap;
+     font-size: 0.8em;
+     background-color: #f0f0f0;
+     border: 1px solid #bbbbdd;
+}
+ .nav li:first-child {
+     border-left: none;
+}
+ .nav li {
+     border-right: 1px solid #bbbbdd;
+     border-left: 1px solid #ffffff;
+}
+ .nav a {
+     padding: 0.4em 1em;
+     display: inline-block;
+     text-decoration: none;
+     font-family: arial, sans;
+}
+ .nav a:hover {
+     background-color: #e0e0e0;
+}
+ .nav a:link {
+     color: #44d;
+}
+ .nav a:visited {
+     color: #44d;
+}
+ .nav a.here {
+     background-color: #e0e0e0;
+}
+ @media only screen and (max-device-width: 480px) {
+     article, .container {
+         width: 100%;
+    }
+     html {
+         font-size: 13px;
+    }
+}