body {
  font-family: helvetica, arial, sans-serif;
}

code{}

p {
  min-height: 1px;
}

h1, h2, h3, h4, h5 {
  padding-top: 20px;
}

/*---*/

.message {
  position: fixed;
  width: 90%;
  padding: 20px 10px;
  z-index: 2;
}

  .message.error {
    background-color: #fdd;
    color: #900;
    border: 1px solid #900;
  }

  .message.notice {
    background-color: #dfd;
    color: #090;
    border: 1px solid #090;
  }

#first_page {
  width: 90%;
  margin: 0 auto;
  padding-top: 20px;
}

  #first_page h1 {
    font-size: 1.5em;
    font-weight: bold;
  }

  #classnotes_description {
    line-height: 1.7em;
  }

  .google_ad, .trial_1 {
    margin: 15px 0;
    width: 335px;
    background-color: #eee;
  }

  #contribute {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1;
    width: 125px;
    text-align: center;
    background-color: #fff;
  }

    .book_ad p, #contribute p {
      font-size: 10px;
    }

    .book_ad img {
      width: 200px;
    }

/*---*/

nav {
  display: none;
}

  nav ol ol > ol {
    margin-left: 20px;
  }

  nav ol ol > ol ol {
    margin-left: 30px;
  }

  nav ol ol > ol ol ol {
    margin-left: 40px;
  }

  nav ol.nav-pills li {
    float: none;
  }

  nav ol.nav-pills li a {
    padding: 2px 5px 2px 10px;
  }

/*---*/

#notes {
  width: 90%;
  margin: 0 auto;
  padding-top: 20px;
}

/* --------------------- */

@media screen and (min-width: 736px) {
  body {}

  #classnotes_description {
    width: 60%;
  }

  #sidebar {
    position: absolute;
    top: 100px;
    right: 30px;
    width: 468px;
    text-align: right;
  }

  .book_ad {
  }

    .book_ad img {
      width: 300px;
    }

  .google_ad, .trial_1 {
    width: 468px;
  }

  nav {
    display: block;
    width: 30%;
    margin-left: 5%;
  }

  #notes {
    width: 55%;
    margin-left: 40%;
    margin-right: 5%;
  }
}