normalize.css--样式重置文件

保护有用的浏览器默认样式而不是完全去掉它们

一般化的样式：为大部分HTML元素提供

修复浏览器自身的bug并保证各浏览器的一致性

优化CSS可用性：用一些小技巧

解释代码：用注释和详细的文档来

/*! normalize.css v8.0.1 | MIT License | github.com/necolas/normalize.css */

/* Document
   ========================================================================== */

/**
 * 1. Correct the line height in all browsers.
 * 2. Prevent adjustments of font size after orientation changes in iOS.
 */

html {
	line-height: 1.15;
	/* 1 */
	-webkit-text-size-adjust: 100%;
	/* 2 */
}

/* Sections
   ========================================================================== */

/**
 * Remove the margin in all browsers.
 */

body {
	margin: 0;
}

/**
 * Render the `main` element consistently in IE.
 */

main {
	display: block;
}

/**
 * Correct the font size and margin on `h1` elements within `section` and
 * `article` contexts in Chrome, Firefox, and Safari.
 */

h1 {
	font-size: 2em;
	margin: 0.67em 0;
}

/* Grouping content
   ========================================================================== */

/**
 * 1. Add the correct box sizing in Firefox.
 * 2. Show the overflow in Edge and IE.
 */

hr {
	box-sizing: content-box;
	/* 1 */
	height: 0;
	/* 1 */
	overflow: visible;
	/* 2 */
}

/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */

pre {
	font-family: monospace, monospace;
	/* 1 */
	font-size: 1em;
	/* 2 */
}

/* Text-level semantics
   ========================================================================== */

/**
 * Remove the gray background on active links in IE 10.
 */

a {
	background-color: transparent;
}

/**
 * 1. Remove the bottom border in Chrome 57-
 * 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.
 */

abbr[title] {
	border-bottom: none;
	/* 1 */
	text-decoration: underline;
	/* 2 */
	text-decoration: underline dotted;
	/* 2 */
}

/**
 * Add the correct font weight in Chrome, Edge, and Safari.
 */

b,
strong {
	font-weight: bolder;
}

/**
 * 1. Correct the inheritance and scaling of font size in all browsers.
 * 2. Correct the odd `em` font sizing in all browsers.
 */

code,
kbd,
samp {
	font-family: monospace, monospace;
	/* 1 */
	font-size: 1em;
	/* 2 */
}

/**
 * Add the correct font size in all browsers.
 */

small {
	font-size: 80%;
}

/**
 * Prevent `sub` and `sup` elements from affecting the line height in
 * all browsers.
 */

sub,
sup {
	font-size: 75%;
	line-height: 0;
	position: relative;
	vertical-align: baseline;
}

sub {
	bottom: -0.25em;
}

sup {
	top: -0.5em;
}

/* Embedded content
   ========================================================================== */

/**
 * Remove the border on images inside links in IE 10.
 */

img {
	border-style: none;
}

/* Forms
   ========================================================================== */

/**
 * 1. Change the font styles in all browsers.
 * 2. Remove the margin in Firefox and Safari.
 */

button,
input,
optgroup,
select,
textarea {
	font-family: inherit;
	/* 1 */
	font-size: 100%;
	/* 1 */
	line-height: 1.15;
	/* 1 */
	margin: 0;
	/* 2 */
}

/**
 * Show the overflow in IE.
 * 1. Show the overflow in Edge.
 */

button,
input {
	/* 1 */
	overflow: visible;
}

/**
 * Remove the inheritance of text transform in Edge, Firefox, and IE.
 * 1. Remove the inheritance of text transform in Firefox.
 */

button,
select {
	/* 1 */
	text-transform: none;
}

/**
 * Correct the inability to style clickable types in iOS and Safari.
 */

button,
[type="button"],
[type="reset"],
[type="submit"] {
	-webkit-appearance: button;
}

/**
 * Remove the inner border and padding in Firefox.
 */

button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
	border-style: none;
	padding: 0;
}

/**
 * Restore the focus styles unset by the previous rule.
 */

button:-moz-focusring,
[type="button"]:-moz-focusring,
[type="reset"]:-moz-focusring,
[type="submit"]:-moz-focusring {
	outline: 1px dotted ButtonText;
}

/**
 * Correct the padding in Firefox.
 */

fieldset {
	padding: 0.35em 0.75em 0.625em;
}

/**
 * 1. Correct the text wrapping in Edge and IE.
 * 2. Correct the color inheritance from `fieldset` elements in IE.
 * 3. Remove the padding so developers are not caught out when they zero out
 *    `fieldset` elements in all browsers.
 */

legend {
	box-sizing: border-box;
	/* 1 */
	color: inherit;
	/* 2 */
	display: table;
	/* 1 */
	max-width: 100%;
	/* 1 */
	padding: 0;
	/* 3 */
	white-space: normal;
	/* 1 */
}

/**
 * Add the correct vertical alignment in Chrome, Firefox, and Opera.
 */

progress {
	vertical-align: baseline;
}

/**
 * Remove the default vertical scrollbar in IE 10+.
 */

textarea {
	overflow: auto;
}

/**
 * 1. Add the correct box sizing in IE 10.
 * 2. Remove the padding in IE 10.
 */

[type="checkbox"],
[type="radio"] {
	box-sizing: border-box;
	/* 1 */
	padding: 0;
	/* 2 */
}

/**
 * Correct the cursor style of increment and decrement buttons in Chrome.
 */

[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
	height: auto;
}

/**
 * 1. Correct the odd appearance in Chrome and Safari.
 * 2. Correct the outline style in Safari.
 */

[type="search"] {
	-webkit-appearance: textfield;
	/* 1 */
	outline-offset: -2px;
	/* 2 */
}

/**
 * Remove the inner padding in Chrome and Safari on macOS.
 */

[type="search"]::-webkit-search-decoration {
	-webkit-appearance: none;
}

/**
 * 1. Correct the inability to style clickable types in iOS and Safari.
 * 2. Change font properties to `inherit` in Safari.
 */

::-webkit-file-upload-button {
	-webkit-appearance: button;
	/* 1 */
	font: inherit;
	/* 2 */
}

/* Interactive
   ========================================================================== */

/*
 * Add the correct display in Edge, IE 10+, and Firefox.
 */

details {
	display: block;
}

/*
 * Add the correct display in all browsers.
 */

summary {
	display: list-item;
}

/* Misc
   ========================================================================== */

/**
 * Add the correct display in IE 10+.
 */

template {
	display: none;
}

/**
 * Add the correct display in IE 10.
 */

[hidden] {
	display: none;
}

reset.css 

/* 
  * reset 的目的不是让默认样式在所有浏览器下一致，而是减少默认样式有可能带来的问题。
  * The purpose of reset is not to allow default styles to be consistent across all browsers, but to reduce the potential problems of default styles.
  * create by jsliang
*/

/** 清除内外边距 - clearance of inner and outer margins **/
body, h1, h2, h3, h4, h5, h6, hr, p, blockquote, /* 结构元素 - structural elements */
dl, dt, dd, ul, ol, li, /* 列表元素 - list elements */
pre, /* 文本格式元素 - text formatting elements */
form, fieldset, legend, button, input, textarea, /* 表单元素 - from elements */
th, td /* 表格元素 - table elements */ {
  margin: 0;
  padding: 0;
}

/** 设置默认字体 - setting the default font **/
body, button, input, select, textarea {
  font: 18px/1.5 '黑体', Helvetica, sans-serif;
}
h1, h2, h3, h4, h5, h6, button, input, select, textarea { font-size: 100%; }

/** 重置列表元素 - reset the list element **/
ul, ol { list-style: none; }

/** 重置文本格式元素 - reset the text format element **/
a, a:hover { text-decoration: none; }

/** 重置表单元素 - reset the form element **/
button { cursor: pointer; }
input { font-size: 18px; outline: none; }

/** 重置表格元素 - reset the table element **/
table { border-collapse: collapse; border-spacing: 0; }

/** 图片自适应 - image responsize **/
img { border: 0; display: inline-block; width: 100%; max-width: 100%; height: auto; vertical-align: middle; }

/* 
    * 默认box-sizing是content-box，该属性导致padding会撑大div，使用border-box可以解决该问题
    * set border-box for box-sizing when you use div, it solve the problem when you add padding and don't want to make the div width bigger
*/
div, input { box-sizing: border-box; }

/** 清除浮动 - clear float **/
.jsliang-clear:after, .clear:after {
  content: '\20';
  display: block;
  height: 0;
  clear: both;
}
.jsliang-clear, .clear {
  *zoom: 1;
}

/** 设置input的placeholder - set input placeholder **/
input::-webkit-input-placeholder { color: #919191; font-size: .26rem } /* Webkit browsers */
input::-moz-placeholder { color: #919191; font-size: .26rem } /* Mozilla Firefox */
input::-ms-input-placeholder { color: #919191; font-size: .26rem } /* Internet Explorer */