styles.css

html {
    background-color: #ddd;
    font: 14px "Helvetica Neue", Helvetica, Arial, sans-serif;
}
.editable {
    border: 1px solid #aaa;
    font: 14px Georgia, serif;
    height: 600px;
    background: #ccc;
    overflow-y: scroll;
}
.editable > * {
    position: relative;
    padding: 8px 12px;
    background: white;
    margin: 0;
    margin-right: 224px;
}
.editable > blockquote {
    padding: 8px 48px;
}
.editable .selected-block, .editable .current {
    background: #ddf;
}
.editable hr {
    padding: 0;
}
.editable-bold {
    font-weight: bold;
}
.editable-italic {
    font-style: italic;
}
.noselect {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}
body {
    background: #eee;
    margin: auto;
    max-width: 1000px;
    padding: 50px 75px;
}
.first-block, .last-block {
    position: relative;
}
.first-block:before {
    content: " ";
    display: block;
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    background-color: #afa;
    width: 4px;
}
.last-block:after {
    content: " ";
    display: block;
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    background-color: #faa;
    width: 4px;
}
.caret, .sel-start, .sel-end {
    display: inline-block;
    font-size: inherit;
    line-height: inherit;
    width: 2px;
    border: 0;
    padding: 0;
    margin-left: -1px;
    margin-right: -1px;
    margin-bottom: -4px;
    margin-top: -6px;
    background-color: black;
}
.sel-start {
    min-height: 6px;
    background-color: green;
}
.sel-end {
    min-height: 6px;
    background-color: red;
}

.caret {
    animation: blink 1s steps(2, start) infinite;
    -webkit-animation: blink 1s steps(2, start) infinite;
}
.caret:focus {
    outline: none;
}
@keyframes blink {
    to {
        background-color: transparent;
    }
}
@-webkit-keyframes blink {
    to {
        background-color: transparent;
    }
}
.tools label {
    font-size: 10px;
}
.tools button {
    background-color: #ccc;
}
.editable-active-for-selection {
    background-color: #bbd;
}
.spanified-word {
    display: inline-block;
}

.debug .spanified {
    border-right: 1px solid rgba(0,0,0,0.25);
    margin-right: -1px;
}

.selected, .selected-unwrap {
    background-color: rgba(0,0,255,0.3);
}

/* Annotations */

.annotation-template {
    display: none;
}

.annotation:after {
    position: relative;
    top: -4px;
    content: "\2020";
}
.annotation > span {
    display: block;
    padding: 4px 8px;
    font-weight: normal;
    font-style: normal;
    font-size: 12px "Helvetica Neue", Helvetica, Arial, Sans-serif;
    background-color: #ffc;
    position: absolute;
    right: -212px;
    max-width: 200px;
}
.editable ul, .editable ol {
    padding-left: 30px;
}