text-shadow: 0 0 20px #333;
padding: 2px 5px;
}
+ .indexlink {
+ position: absolute;
+ bottom: 1em;
+ left: 1em;
+ }
</style>
</head>
<body>
---
+layout: true
+
+.indexlink[[Index](index.html)]
+
+---
+
# Enciphering and deciphering
## Arithmetic on letters