1. Absolute and float have the same characteristics, wrapping and destructiveness
1. Absolute and float are similar (see the demo below, if the picture is in the upper left corner, then using float and absolute will be the same )
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <meta name="viewport" content="width=device-width"> 6 <title>absolute和float高尔基</title> 7 <style> 8 body { 9 background-color: #B0DEF5; 10 font-size: 14px; font-family: arial; 11 color: #444; 12 } 13 a { 14 color: #0078b6; 15 text-decoration: none; 16 } 17 a:hover { 18 text-decoration: underline; 19 } 20 em { 21 font-style: normal; 22 color: #aeaeae; 23 margin: 0 5px; 24 } 25 svg { 26 position: absolute; 27 } 28 .container { 29 width: 560px; height: -webkit-calc(100vh - 16px); height: calc(100vh - 16px); 30 margin-left: auto; margin-right: auto; 31 background-color: #fff; 32 } 33 .list { 34 padding: 20px; 35 position: relative; 36 } 37 .space { 38 padding-left: 60px; 39 line-height: 22px; 40 } 41 .space img { 42 vertical-align: text-bottom; 43 } 44 .info { 45 font-size: 12px; 46 overflow: hidden; 47 color: #808080; 48 } 49 .from { 50 float: left; 51 } 52 .from a { 53 color: #9abbc8; 54 } 55 p { 56 margin: 6px 0; 57 } 58 .operate { 59 float: right; 60 } 61 .operate img { 62 vertical-align: text-bottom; 63 margin-right: 3px; 64 } 65 .test { 66 position: relative; 67 font-size: 18px; font-family: 'microsoft yahei'; 68 } 69 .test p { 70 width: 200px; 71 margin-left: auto; margin-right: auto; 72 padding: 5px; 73 background-color: #f0f0f0; 74 } 75 .test input { 76 width: 20px; height: 20px; 77 vertical-align: -4px; 78 } 79 </style> 80 </head> 81 82 <body> 83 <p class="container"> 84 <svg xmlns="http://www.w3.org/2000/svg" width="520" height="360"> 85 <path d="M45 80C45 280,45 320,165 300" stroke-width="1" stroke="#444" fill="none"></path> 86 </svg> 87 <p class="list"> 88 <a href="#" id="avatar" class="avatar" style="float: left;"><img src="http://img.mukewang.com/54447ac70001f5cc00500050.jpg"></a> 89 <p class="space"> 90 <a href="//weibo.com/mukewang" target="_blank" title="慕课网">慕课网</a> 91 <img src="http://img.mukewang.com/54447b1a0001750000160013.png"> 92 <a href="http://huati.weibo.com/k/%E6%85%95%E8%AF%BE%E7%BD%91%E6%B4%BB%E5%8A%A8?from=501">#慕课网活动#</a>【全民晒课ing，火速赢取IT图书】无论你是慕课网的“资深粉丝”，还是刚加入的新同学，在慕课网活动帖：<a href="http://www.imooc.com/wenda/detail/30394">//m.sbmmt.com/</a> 写下你在慕课网所学习的任意一门课程，并附上课程的学习心得，就有机会赢得精品IT好书。<img src="http://img.mukewang.com/54447cc700010dbf00220022.gif">这事很急哒，仅有2天呦。在<a href="http://huati.weibo.com/k/%E7%A8%8B%E5%BA%8F%E5%91%98%E8%8A%82?from=501">#程序员节#</a>送给自己一份礼物吧！<img src="http://img.mukewang.com/54447af90001ab1c00010001.gif"> 93 <p><img src="http://img.mukewang.com/54447aea0001f43301200084.jpg"></p> 94 <p class="info"> 95 <span class="from"> 96 <a href="#">9月13日 10:27</a> 97 <em>来自</em><a href="#">微博 weibo.com</a> 98 </span> 99 <span class="operate">100 <a href="javascript:" title="赞"><img src="http://img.mukewang.com/54447c350001055b00120013.png">(4)</a><em>|</em>101 <a href="javascript:">转发(5)</a><em>|</em>102 <a href="javascript:">收藏</a><em>|</em>103 <a href="javascript:">评论(2)</a>104 </span>105 </p>106 </p>107 </p>108 <p class="test">109 <p><input type="radio" name="layout" id="float" checked><label for="float">float: left;</label></p>110 <p><input type="radio" name="layout" id="absolute"><label for="absolute">position: absolute;</label></p>111 </p>112 </p>113 <script>114 var eleAvatar = document.getElementById("avatar"),115 eleFloat = document.getElementById("float"),116 eleAbsolute = document.getElementById("absolute");117 118 // SVG路径以及相关动画119 var elePath = document.querySelector("path"), timerPath = null;
120 var funPathMove = function(end) {121 clearTimeout(timerPath);122 var d = elePath.getAttribute("d"), arrD = d.split(" ");123 // 动画起始值124 var start = arrD.slice(-1) * 1;125 if (start == end) return;126 // 速率127 var rate = 5, current = start;128 console.log(arrD);129 var step = function() {130 if (Math.abs(end - current) < 1) {131 current = end;132 } else {133 current += (end - current) / 5;134 timerPath = setTimeout(step, 30);135 }136 // 替换最后一个值137 arrD.splice(-1, 1, current);138 // 曲线走起139 elePath.setAttribute("d", arrD.join(" "));140 };141 step();142 };143 144 if (eleAvatar && eleFloat && eleAbsolute) {145 var attrFloat = eleAvatar.style.cssFloat != undefined? "cssFloat": "styleFloat";146 eleFloat.onclick = function() {147 eleAvatar.style.position = "";148 eleAvatar.style[attrFloat] = "left";149 elePath && funPathMove(300);150 };151 eleAbsolute.onclick = function() {152 eleAvatar.style[attrFloat] = "";153 eleAvatar.style.position = "absolute";154 elePath && funPathMove(340);155 };156 }157 </script>158 </body>159 </html>View Code
2、Destructive
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <meta name="viewport" content="width=device-width"> 6 <title>absolute的破坏性</title> 7 <style> 8 .box { 9 padding: 10px;10 background-color: #f0f0f0; 11 }12 input {13 position: absolute; top: 234px; 14 width: 160px; height: 32px;15 font-size: 100%;16 }17 </style>18 </head>19 20 <body>21 <p class="box"><img id="image" src="http://img.mukewang.com/54447b06000171a002560191.jpg" width="256" height="191"></p>22 <input id="button" type="button" value="图片absolute化">23 <script>24 var eleImg = document.getElementById("image"), eleBtn = document.getElementById("button");25 if (eleImg != null && eleBtn != null) {26 eleBtn.onclick = function() {27 if (this.absolute) {28 eleImg.style.position = "";29 this.value = "图片absolute化";30 this.absolute = false;31 } else {32 eleImg.style.position = "absolute";33 this.value = "图片去absolute";34 this.absolute = true;35 }36 };37 }38 </script>39 </body>40 </html>View Code
3. Packageability
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <meta name="viewport" content="width=device-width"> 6 <title>absolute的包裹性</title> 7 <style> 8 .box { 9 padding: 10px;10 background-color: #f0f0f0; 11 }12 input {13 position: absolute; top: 234px; 14 width: 160px; height: 32px;15 font-size: 100%;16 }17 </style>18 </head>19 20 <body>21 <p id="box" class="box"><img src="http://img.mukewang.com/54447b06000171a002560191.jpg" width="256" height="191"></p>22 <input id="button" type="button" value="容器absolute化">23 <script>24 var eleBox = document.getElementById("box"), eleBtn = document.getElementById("button");25 if (eleBox != null && eleBtn != null) {26 eleBtn.onclick = function() {27 if (this.absolute) {28 eleBox.style.position = "";29 this.value = "容器absolute化";30 this.absolute = false;31 } else {32 eleBox.style.position = "absolute";33 this.value = "容器去absolute";34 this.absolute = true;35 }36 };37 }38 </script>39 </body>40 </html>View Code
2. The independence of absolute
When using absolute, it does not have to be used together with relative. It can be used independently, and the more independent it is, the greater its capabilities
3. Absolute features
1. Remove float
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>折翼天使表现特性一：去浮动</title> 6 <style> 7 input[type=button] { 8 height: 32px; 9 font-size: 100%; 10 }11 </style>12 </head>13 14 <body>15 <img src="http://img.mukewang.com/54447b06000171a002560191.jpg">16 <img src="http://img.mukewang.com/54447f4a0001eb7d01910256.jpg">17 <img src="http://img.mukewang.com/54447f550001ccb002560191.jpg">18 <p><input type="button" id="float" value="点击第2张图片应用float:left"></p>19 <p><input type="button" id="button" value="点击第2张图片应用position:absolute"></p>20 <script>21 var flbtn = document.getElementById("float"),22 button = document.getElementById("button"),23 image2 = document.getElementsByTagName("img")[1];24 if (flbtn && button && image2) {25 var value_init = button.value;26 button.onclick = function() {27 if (this.value == value_init) {28 image2.style.position = "absolute";29 this.value = "撤销";30 } else {31 image2.style.position = "";32 this.value = value_init;33 }34 };35 36 flbtn.onclick = function() {37 image2.style["cssFloat" in this.style? "cssFloat": "styleFloat"] = "left";38 };39 }40 </script>41 </body>42 </html>##View Code
2. Position follow 1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>折翼天使表现特性二：位置跟随</title> 6 <style> 7 input[type=button] { 8 height: 32px; 9 font-size: 100%;10 }11 p { margin-left: 260px; }12 img + p { margin-top: 60px; }13 </style>14 </head>15 16 <body>17 <img src="http://img.mukewang.com/54447b06000171a002560191.jpg">18 <p><img src="http://img.mukewang.com/54447f4a0001eb7d01910256.jpg"></p>19 <img src="http://img.mukewang.com/54447f550001ccb002560191.jpg">20 <p><input type="button" id="block" value="点击第2张图片应用display:block"></p>21 <p><input type="button" id="button" value="点击第2张图片应用position:absolute变天使"></p>22 <script>23 var block = document.getElementById("block"),24 button = document.getElementById("button"),25 image2 = document.getElementsByTagName("img")[1];26 if (block && button && image2) {27 var value_init_button = button.value;28 button.onclick = function() {29 if (this.value == value_init_button) {30 image2.style.position = "absolute";31 this.value = "撤销";32 } else {33 image2.style.position = "";34 this.value = value_init_button;35 }36 };37 38 var value_init_block = block.value;39 block.onclick = function() {40 if (this.value == value_init_block) {41 image2.style.display = "block";42 this.value = "撤销";43 } else {44 image2.style.display = "";45 this.value = value_init_block;46 }
47 };48 }49 </script>50 </body>51 </html>View Code
3.Beyond overflow 1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>超越overflow</title> 6 <style> 7 body { 8 background-color: #bbb; 9 }10 .scroll {11 width: 500px; height: 300px;12 margin: 200px auto 0;13 margin-top: -webkit-calc(50vh - 150px);14 margin-top: calc(50vh - 150px);15 border: 1px solid #ccc;16 border-radius: 3px;17 box-shadow: 0 0 3px rgba(0,0,0,.35);18 background-color: #fff;19 overflow: auto;20 }21 .close {22 position: absolute;23 width: 34px; height: 34px; 24 margin: -17px 0 0 483px;25 background: url(//m.sbmmt.com/) no-repeat;26 }27 .close:hover {28 background-position: 0 -41px; 29 }30 img {31 display: block;32 margin: 10px;33 }34 </style>35 </head>36 37 <body>38 <p class="scroll">39 <a href="javascript:" class="close" title="关闭"></a>40 <img src="http://img.mukewang.com/54447b06000171a002560191.jpg">41 <img src="http://img.mukewang.com/54447f550001ccb002560191.jpg">42 </p>43 </body>44 </html>View Code
When the scroll bar is slid, the close button does not move because absoluteis set
4. Actual use of absolute1. Absolute positioning coverage of picture icons
##Hot, recommendation, and vip in the above picture are all implemented with absolute Yes, and not using relative
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>图标定位二三事</title> 6 <style> 7 body { font: 14px/1.4 "Microsoft YaHei"; background-color: #EDEFF0; } 8 body, h3, h5 { margin: 0; } 9 img { border: 0 none; vertical-align: bottom; }10 .l { float: left; }.r { float: right; }11 .constr { width: 1200px; margin-left: auto; margin-right: auto; }12 .header { background-color: #2A2C2E; }13 .nav { height: 60px; }14 .nav-list { float: left; font-size: 14px; font-weight: 400; }15 .nav-a { display: inline-block; line-height: 20px; padding: 20px 35px; color: #B5BDC0; text-decoration: none; }16 .nav-a:hover { color: #fff; }17 18 .course { padding-top: 10px; }19 .course-list { float: left; width: 280px; height: 240px; margin: 5px 10px 15px; border-radius: 0 0 1px 1px; background-color: #F7FAF9; background-color: rgba(255,255,255,1); box-shadow: 0 1px 2px #c5c5c5; text-decoration: none; }20 .course-list-img { background-color: #6396F1; }21 .course-list-h { line-height: 50px; font-size: 14px; font-weight: 400; color: #363d40; text-align: center; }22 .course-list-tips { margin: 0 14px; font-size: 12px; color: #b4bbbf; overflow: hidden; }23 24 .icon-hot { position: absolute; width: 28px; height: 11px; margin: -6px 0 0 2px; background: url(//m.sbmmt.com/); }25 .icon-recom { position: absolute; line-height: 20px; padding: 0 5px; background-color: #f60; color: #fff; font-size: 12px; }26 .icon-vip { position: absolute; width: 36px; height: 36px; margin-left: -36px; background: url(//m.sbmmt.com/); text-indent: -9em; overflow: hidden; }27 </style>28 </head>29 30 <body>31 <p class="header">32 <p class="constr">33 <p class="nav">34 <h3 class="nav-list">35 <a href="http://www.imooc.com/course/list" class="nav-a">课程</a>36 </h3>37 <h3 class="nav-list">38 <a href="http://www.imooc.com/wenda" class="nav-a">问答</a>39 </h3>40 <h3 class="nav-list">41 <a href="http://www.imooc.com/seek/index" class="nav-a">42 求课<i class="icon-hot"></i>43 </a>44 </h3>45 </p>46 </p>47 </p>48 49 <p class="main">50 <p class="constr">51 <p class="course">52 <a href="http://www.imooc.com/view/121" class="course-list">53 <p class="course-list-img">54 <span class="icon-recom">推荐</span>55 <img width="280" height="160" alt="分享：CSS深入理解之float浮动" src="http://img.mukewang.com/53d74f960001ae9d06000338-300-170.jpg"><!--56 --><i class="icon-vip">vip</i>57 </p>58 <h5 class="course-list-h">分享：CSS深入理解之float浮动</h5>59 <p class="course-list-tips">60 <span class="l">已完结</span>61 <span class="r">3514人学习</span>62 </p>63 </a>64 </p>65 </p>66 </p>67 </body>68 </html>#2. Drop-down box positioning
Use dependency-free absolute positioning, that is, only absolute is used, not relative
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>下拉框定位二三事</title> 6 <style> 7 body { margin: 0; font: 14px/1.4 "Microsoft YaHei"; background-color: #EDEFF0; } 8 .constr { width: 1200px; max-width: 80%; margin-left: auto; margin-right: auto; padding-bottom: 300px; overflow: hidden; } 9 .course-sidebar { width: 262px; float: left; }10 .course-sidebar > p { border: 1px solid #e6e8e9; box-shadow: 0px 1px 2px #d5d7d8; background-color: #fff; }11 .course-sidebar-type { height: 380px; }12 .course-sidebar-search { margin-top: 20px; overflow: hidden; }13 .course-search-input { width: 200px; line-height: 18px; padding: 10px; margin: 0; border: 0 none; font-size: 12px; font-family: inherit; float: left; }14 .course-sidebar-search.focus { border-color: #2ea7e0; }15 .course-search-input:focus { outline: 0 none; }16 .course-search-input::-ms-clear { display: none; }17 .course-search-btn { width: 38px; height: 38px; float: right; background: url(//m.sbmmt.com/); text-indent: -9em; overflow: hidden; }18 .focus .course-search-btn { background-position: 0 -38px; }19 20 .course-sidebar-result { display: none; position: absolute; width: 260px; margin: 39px 0 0 -1px; padding-left: 0; list-style-type: none; border: 1px solid #e6e8e9; background-color: #fff; box-shadow: 0px 1px 2px #d5d7d8; font-size: 12px; }21 .course-sidebar-result > li { line-height: 30px; padding-left: 12px; }22 .course-sidebar-result > li:hover { background-color: #f9f9f9; }23 .course-sidebar-result a { display: block; color: #5e5e5e; text-decoration: none; }24 .course-sidebar-result a:hover { color: #000; }25 </style>26 </head>27 28 <body>29 <p class="constr">30 <p class="course-sidebar">31 <p class="course-sidebar-type"></p>32 <p class="course-sidebar-search">33 <ul id="result" class="course-sidebar-result">34 <li><a href="http://www.imooc.com/view/121">分享：CSS深入理解之float浮动</a></li>35 <li><a href="http://www.imooc.com/view/118">案例：CSS圆角进化论</a></li>36 <li><a href="http://www.imooc.com/view/93">案例：CSS Sprite雪碧图应用</a></li>37 <li><a href="http://www.imooc.com/view/77">案例：CSS3 3D 特效</a></li>38 <li><a href="http://www.imooc.com/view/57">案例：如何用CSS进行网页布局</a></li>39 </ul>40 <input class="course-search-input" placeholder="课程搜索">41 <a href="javascript:" class="course-search-btn">搜索</a>42 </p>43 </p>44 </p>45 <script>46 (function() {47 var input = document.getElementsByTagName("input")[0],48 result = document.getElementById("result");49 50 if (input && result) {51 input.onfocus = function() {52 this.parentNode.className = "course-sidebar-search focus";53 if (this.value != "") {54 // show datalist55 result.style.display = "block";56 }57 };58 input.onblur = function() {59 if (this.value == "") {60 this.parentNode.className = "course-sidebar-search";61 }62 // hide datalist63 result.style.display = "none";64 };65 66 // IE7 that wrap a p for avoid bad effect from float67 if (!document.querySelector) {68 var p = document.createElement("p");69 input.parentNode.insertBefore(p, input);70 p.appendChild(result);71 }72 // events of datalist73 if ("oninput" in input) {74 input.addEventListener("input", function() {75 if (this.value.trim() != "") {76 result.style.display = "block";77 } else {78 result.style.display = "none";79 }80 });81 } else {82 // IE6-IE883 input.onpropertychange = function(event) {84 event = event || window.event;85 if (event.propertyName == "value" && /focus/.test(this.parentNode.className)) {86 if (this.value != "") {87 result.style.display = "block";88 } else {89 result.style.display = "none";90 }91 }92 }93 }94 }95 96 })();97 </script>98 </body>99 </html>3. Centering and edge positioning
An idea to achieve image centering and edge positioning, you can use unlimited absolute, which uses To understand the followability of and absolute, pay attention to the
in the code, this is very important
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>居中、边缘定位二三事</title> 6 <style> 7 body { margin: 0; font: 14px/1.4 "Microsoft YaHei"; background-color: #EDEFF0; } 8 .constr { width: 1200px; max-width: 80%; margin-left: auto; margin-right: auto; } 9 .course-content { float: right; position: relative; width: 920px; min-height: 1200px; background: #fff; }10 .course-list-x { padding: 20px 10px; overflow: hidden; }11 .course-list { float: left; width: 280px; height: 240px; margin: 5px 10px 15px; border-radius: 0 0 1px 1px; background-color: #F7FAF9; background-color: rgba(255,255,255,1); box-shadow: 0 1px 2px #c5c5c5; text-decoration: none; }12 13 .goto_top_diaocha, .goto_top_app, .goto_top_feed { display: block; width: 48px; height: 48px; margin-top: 10px; background: url(//m.sbmmt.com/) no-repeat; }14 .goto_top_diaocha { background-position: -48px 0; }15 .goto_top_diaocha:hover { background-position: -48px -50px; }16 .goto_top_app { background-position: -96px 0; }17 .goto_top_app:hover { background-position: -96px -50px; }18 .goto_top_feed { background-position: -144px 0; }19 .goto_top_feed:hover { background-position: -144px -50px; }20 21 .course-loading-x { height: 0; margin-top: 20px; text-align: center; letter-spacing: -.25em; overflow: hidden; }22 .course-loading { position: absolute; margin-left: -26px; }23 24 .course-fixed-x { height: 0; text-align: right; overflow: hidden; }25 .course-fixed { display: inline; position: fixed; margin-left: 20px; bottom: 100px; }26 </style>27 </head>28 29 <body>30 <p class="constr">31 <p class="course-content">32 <p class="course-list-x">33 <p class="course-list"></p>34 <p class="course-list"></p>35 <p class="course-list"></p>36 <p class="course-list"></p>37 <p class="course-list"></p>38 <p class="course-list"></p>39 </p>40 <p class="course-loading-x">41 <img src="http://img.mukewang.com/5453077400015bba00010001.gif" class="course-loading" alt="加载中...">42 </p>43 <p class="course-fixed-x">44 <p class="course-fixed">45 <a href="http://www.imooc.com/activity/diaocha" class="goto_top_diaocha"></a>46 <a href="http://www.imooc.com/mobile/app" class="goto_top_app"></a>47 <a href="http://www.imooc.com/user/feedback" class="goto_top_feed"></a>48 </p>49 </p>50 </p>51 </p>52 </body>53 </html>4. Align and position files and pictures
In actual projects, some places have stars and some don’t. I want to align them with text. If it is more troublesome, you can use the dependency-free absolute
. The icon in front of the mailbox and the text beyond the box can be used without the dependency absolute
. It provides a new layout for the page. Idea
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>文本图标对齐与定位二三事</title> 6 <style> 7 body { margin: 0; font: 14px/1.4 "Microsoft YaHei"; background-color: #EDEFF0; } 8 a { color: #50B6E5; } 9 .constr { width: 1200px; margin-left: auto; margin-right: auto; }10 .regist-head { height: 60px; line-height: 60px; padding-left: 30px; background-color: #be3948; color: #fff; font-size: 18px; }11 .regist-body { min-height: 400px; padding: 100px 0; background-color: #fff; }12 .regist-main { width: 600px; margin-left: auto; margin-right: auto; }13 .regist-group { margin-top: 20px; overflow: hidden; }14 .regist-label { width: 70px; padding-top: 10px; float: left; }15 .regist-cell { display: table-cell; *display: inline-block; }16 .regist-input { height: 18px; line-height: 18px; width: 260px; padding: 10px 5px; margin: 0 10px 0 0; border: 1px solid #d0d6d9; vertical-align: top; }17 .regist-code-input { width: 130px; }18 .regist-btn { display: inline-block; width: 160px; line-height: 40px; background-color: #39b94e; color: #fff; text-align: center; text-decoration: none; }19 .regist-btn:hover { background-color: #33a646; }20 .icon-warn { display: inline-block; width: 20px; height: 21px; background: url(//m.sbmmt.com/) no-repeat center; }21 22 .regist-star { position: absolute; margin-left: -1em; font-family: simsun; color: #f30; }23 .regist-remark { position: absolute; line-height: 21px; padding-top: 9px; color: #666; }24 .regist-warn { padding-left: 20px; color: #be3948; }25 .regist-warn > .icon-warn { position: absolute; margin-left: -20px; }26 </style>27 </head>28 29 <body>30 <p class="constr">31 <p class="regist-head">注册</p>32 <p class="regist-body">33 <p class="regist-main">34 <p class="regist-group">35 <label class="regist-label"><span class="regist-star">*</span>登录邮箱</label>36 <p class="regist-cell">37 <input type="email" class="regist-input"><span class="regist-remark regist-warn">38 <i class="icon-warn"></i>邮箱格式不准确（演示）39 </span>40 </p>41 </p>42 <p class="regist-group">43 <label class="regist-label"><span class="regist-star">*</span>登录密码</label>44 <p class="regist-cell">45 <input type="password" class="regist-input"><span class="regist-remark">46 请输入6-16位密码，区分大小写，不能使用空格47 </span>48 </p>49 </p>50 <p class="regist-group">51 <label class="regist-label"><span class="regist-star">*</span>用户昵称</label>52 <p class="regist-cell">53 <input type="password" class="regist-input">54 </p>55 </p>56 <p class="regist-group">57 <label class="regist-label">手机号码</label>58 <p class="regist-cell">59 <input type="tel" class="regist-input">60 </p>61 </p>62 <p class="regist-group">63 <label class="regist-label"><span class="regist-star">*</span>验 证 码</label>64 <p class="regist-cell">65 <input class="regist-input regist-code-input"><img src="http://img.mukewang.com/545308540001678401500040.jpg">66 </p>67 </p>68 <p class="regist-group">69 <label class="regist-label"> </label>70 <p class="regist-cell">71 <input type="checkbox" checked><label>我已阅读并同意<a href="##">慕课协议</a>。</label>72 <p>73 <a href="javascript:" class="regist-btn">立即注册</a>74 </p>75 </p>76 </p>77 </p>78 </p>79 </p>80 </body>81 </html>4. Absolute separation from document flow
Try to use animation as much as possible It works on absolute, because absolute is separated from the document flow, so that the animation will not affect other elements
z-index无依赖 1.如果只有一个绝对定位元素，自然不需要z-index,自动覆盖普通元素； 2.如果两个绝对定位，控制DOM流的前后顺序达到需要的覆盖效果，依然无z-index； 3.如果多个绝对定位交错，非常非常少见，z-index:1控制； 4.如果非弹窗类的绝对定位元素z-index>2,必定z-index冗余，请优化！
For more in-depth understanding of css absolute related articles, please pay attention to the PHP Chinese website!
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
