add doc site
diff --git a/docs/css/normalize.css b/docs/css/normalize.css
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+/*! normalize.css v3.0.2 | MIT License | git.io/normalize */
+
+/**
+ * 1. Set default font family to sans-serif.
+ * 2. Prevent iOS text size adjust after orientation change, without disabling
+ * user zoom.
+ */
+
+html {
+ font-family: sans-serif; /* 1 */
+ -ms-text-size-adjust: 100%; /* 2 */
+ -webkit-text-size-adjust: 100%; /* 2 */
+}
+
+/**
+ * Remove default margin.
+ */
+
+body {
+ margin: 0;
+}
+
+/* HTML5 display definitions
+ ========================================================================== */
+
+/**
+ * Correct `block` display not defined for any HTML5 element in IE 8/9.
+ * Correct `block` display not defined for `details` or `summary` in IE 10/11
+ * and Firefox.
+ * Correct `block` display not defined for `main` in IE 11.
+ */
+
+article,
+aside,
+details,
+figcaption,
+figure,
+footer,
+header,
+hgroup,
+main,
+menu,
+nav,
+section,
+summary {
+ display: block;
+}
+
+/**
+ * 1. Correct `inline-block` display not defined in IE 8/9.
+ * 2. Normalize vertical alignment of `progress` in Chrome, Firefox, and Opera.
+ */
+
+audio,
+canvas,
+progress,
+video {
+ display: inline-block; /* 1 */
+ vertical-align: baseline; /* 2 */
+}
+
+/**
+ * Prevent modern browsers from displaying `audio` without controls.
+ * Remove excess height in iOS 5 devices.
+ */
+
+audio:not([controls]) {
+ display: none;
+ height: 0;
+}
+
+/**
+ * Address `[hidden]` styling not present in IE 8/9/10.
+ * Hide the `template` element in IE 8/9/11, Safari, and Firefox < 22.
+ */
+
+[hidden],
+template {
+ display: none;
+}
+
+/* Links
+ ========================================================================== */
+
+/**
+ * Remove the gray background color from active links in IE 10.
+ */
+
+a {
+ background-color: transparent;
+}
+
+/**
+ * Improve readability when focused and also mouse hovered in all browsers.
+ */
+
+a:active,
+a:hover {
+ outline: 0;
+}
+
+/* Text-level semantics
+ ========================================================================== */
+
+/**
+ * Address styling not present in IE 8/9/10/11, Safari, and Chrome.
+ */
+
+abbr[title] {
+ border-bottom: 1px dotted;
+}
+
+/**
+ * Address style set to `bolder` in Firefox 4+, Safari, and Chrome.
+ */
+
+b,
+strong {
+ font-weight: bold;
+}
+
+/**
+ * Address styling not present in Safari and Chrome.
+ */
+
+dfn {
+ font-style: italic;
+}
+
+/**
+ * Address variable `h1` font-size and margin within `section` and `article`
+ * contexts in Firefox 4+, Safari, and Chrome.
+ */
+
+h1 {
+ font-size: 2em;
+ margin: 0.67em 0;
+}
+
+/**
+ * Address styling not present in IE 8/9.
+ */
+
+mark {
+ background: #ff0;
+ color: #000;
+}
+
+/**
+ * Address inconsistent and variable font size in all browsers.
+ */
+
+small {
+ font-size: 80%;
+}
+
+/**
+ * Prevent `sub` and `sup` affecting `line-height` in all browsers.
+ */
+
+sub,
+sup {
+ font-size: 75%;
+ line-height: 0;
+ position: relative;
+ vertical-align: baseline;
+}
+
+sup {
+ top: -0.5em;
+}
+
+sub {
+ bottom: -0.25em;
+}
+
+/* Embedded content
+ ========================================================================== */
+
+/**
+ * Remove border when inside `a` element in IE 8/9/10.
+ */
+
+img {
+ border: 0;
+}
+
+/**
+ * Correct overflow not hidden in IE 9/10/11.
+ */
+
+svg:not(:root) {
+ overflow: hidden;
+}
+
+/* Grouping content
+ ========================================================================== */
+
+/**
+ * Address margin not present in IE 8/9 and Safari.
+ */
+
+figure {
+ margin: 1em 40px;
+}
+
+/**
+ * Address differences between Firefox and other browsers.
+ */
+
+hr {
+ -moz-box-sizing: content-box;
+ box-sizing: content-box;
+ height: 0;
+}
+
+/**
+ * Contain overflow in all browsers.
+ */
+
+pre {
+ overflow: auto;
+}
+
+/**
+ * Address odd `em`-unit font size rendering in all browsers.
+ */
+
+code,
+kbd,
+pre,
+samp {
+ font-family: monospace, monospace;
+ font-size: 1em;
+}
+
+/* Forms
+ ========================================================================== */
+
+/**
+ * Known limitation: by default, Chrome and Safari on OS X allow very limited
+ * styling of `select`, unless a `border` property is set.
+ */
+
+/**
+ * 1. Correct color not being inherited.
+ * Known issue: affects color of disabled elements.
+ * 2. Correct font properties not being inherited.
+ * 3. Address margins set differently in Firefox 4+, Safari, and Chrome.
+ */
+
+button,
+input,
+optgroup,
+select,
+textarea {
+ color: inherit; /* 1 */
+ font: inherit; /* 2 */
+ margin: 0; /* 3 */
+}
+
+/**
+ * Address `overflow` set to `hidden` in IE 8/9/10/11.
+ */
+
+button {
+ overflow: visible;
+}
+
+/**
+ * Address inconsistent `text-transform` inheritance for `button` and `select`.
+ * All other form control elements do not inherit `text-transform` values.
+ * Correct `button` style inheritance in Firefox, IE 8/9/10/11, and Opera.
+ * Correct `select` style inheritance in Firefox.
+ */
+
+button,
+select {
+ text-transform: none;
+}
+
+/**
+ * 1. Avoid the WebKit bug in Android 4.0.* where (2) destroys native `audio`
+ * and `video` controls.
+ * 2. Correct inability to style clickable `input` types in iOS.
+ * 3. Improve usability and consistency of cursor style between image-type
+ * `input` and others.
+ */
+
+button,
+html input[type="button"], /* 1 */
+input[type="reset"],
+input[type="submit"] {
+ -webkit-appearance: button; /* 2 */
+ cursor: pointer; /* 3 */
+}
+
+/**
+ * Re-set default cursor for disabled elements.
+ */
+
+button[disabled],
+html input[disabled] {
+ cursor: default;
+}
+
+/**
+ * Remove inner padding and border in Firefox 4+.
+ */
+
+button::-moz-focus-inner,
+input::-moz-focus-inner {
+ border: 0;
+ padding: 0;
+}
+
+/**
+ * Address Firefox 4+ setting `line-height` on `input` using `!important` in
+ * the UA stylesheet.
+ */
+
+input {
+ line-height: normal;
+}
+
+/**
+ * It's recommended that you don't attempt to style these elements.
+ * Firefox's implementation doesn't respect box-sizing, padding, or width.
+ *
+ * 1. Address box sizing set to `content-box` in IE 8/9/10.
+ * 2. Remove excess padding in IE 8/9/10.
+ */
+
+input[type="checkbox"],
+input[type="radio"] {
+ box-sizing: border-box; /* 1 */
+ padding: 0; /* 2 */
+}
+
+/**
+ * Fix the cursor style for Chrome's increment/decrement buttons. For certain
+ * `font-size` values of the `input`, it causes the cursor style of the
+ * decrement button to change from `default` to `text`.
+ */
+
+input[type="number"]::-webkit-inner-spin-button,
+input[type="number"]::-webkit-outer-spin-button {
+ height: auto;
+}
+
+/**
+ * 1. Address `appearance` set to `searchfield` in Safari and Chrome.
+ * 2. Address `box-sizing` set to `border-box` in Safari and Chrome
+ * (include `-moz` to future-proof).
+ */
+
+input[type="search"] {
+ -webkit-appearance: textfield; /* 1 */
+ -moz-box-sizing: content-box;
+ -webkit-box-sizing: content-box; /* 2 */
+ box-sizing: content-box;
+}
+
+/**
+ * Remove inner padding and search cancel button in Safari and Chrome on OS X.
+ * Safari (but not Chrome) clips the cancel button when the search input has
+ * padding (and `textfield` appearance).
+ */
+
+input[type="search"]::-webkit-search-cancel-button,
+input[type="search"]::-webkit-search-decoration {
+ -webkit-appearance: none;
+}
+
+/**
+ * Define consistent border, margin, and padding.
+ */
+
+fieldset {
+ border: 1px solid #c0c0c0;
+ margin: 0 2px;
+ padding: 0.35em 0.625em 0.75em;
+}
+
+/**
+ * 1. Correct `color` not being inherited in IE 8/9/10/11.
+ * 2. Remove padding so people aren't caught out if they zero out fieldsets.
+ */
+
+legend {
+ border: 0; /* 1 */
+ padding: 0; /* 2 */
+}
+
+/**
+ * Remove default vertical scrollbar in IE 8/9/10/11.
+ */
+
+textarea {
+ overflow: auto;
+}
+
+/**
+ * Don't inherit the `font-weight` (applied by a rule above).
+ * NOTE: the default cannot safely be changed in Chrome and Safari on OS X.
+ */
+
+optgroup {
+ font-weight: bold;
+}
+
+/* Tables
+ ========================================================================== */
+
+/**
+ * Remove most spacing between table cells.
+ */
+
+table {
+ border-collapse: collapse;
+ border-spacing: 0;
+}
+
+td,
+th {
+ padding: 0;
+}
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