body{margin-left:5%; margin-right:15%; line-height:150%}
h1, h2, h4{text-align: center}
h3{background-color:navy; color:white}
th{background-color:gray}
table{border-collapse: collapse; empty-cells:show}
dt{font-weight:bold}
blockquote.quote{color:olive}
address{text-align: center}
a:hover{color: red}
hr.chapter{color:navy; height:1ex}
.question{font-weight:bold; border:thin solid gray}
.code{background-color:silver; font-weight:normal; line-height:100%}
.input{font-weight:bold}