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<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>运营系统登录页</title>
 
<link href="static/css/login.css" rel="stylesheet" type="text/css">
<script type="text/javascript" src="static/lib/jquery/1.9.1/jquery.min.js"></script> 
<script src="static/js/verificationNumbers.js" tppabs="static/js/verificationNumbers.js"></script>
<style>
.J_codeimg{z-index:-1;position:absolute;}
</style>

</head>
<body>
<div class="login-box" id="demo">
   <div class="input-content">
     <div class="login_tit">
          <div>
            <i class="tit-bg left"></i>
              Everyday · 运营系统
            <i class="tit-bg right"></i>
          </div>
          <p>Strive&nbsp;&nbsp;&nbsp;&nbsp;Everyday</p>
     </div>    
     <p class="p user_icon">
       <input type="text" placeholder="账号" autocomplete="off" class="login_txtbx">
     </p> 
     <p class="p pwd_icon">
       <input type="text" placeholder="密码" autocomplete="off" class="login_txtbx">
     </p>     	
     <div class="p val_icon">
        <div class="checkcode">
          <input type="text" id="J_codetext" placeholder="验证码" autocomplete="off" maxlength="4" class="login_txtbx">
          <canvas class="J_codeimg" id="myCanvas" onclick="createCode()" onselectstart="return false">对不起，您的浏览器不支持canvas，请下载最新版浏览器!</canvas>
        </div>
        <a class="ver_btn" onclick="createCode();" onselectstart="return false">看不清，换一张</a>
      </div>      
      <div class="signup">
      	  <a class="gv" href="#" onclick="validate()">登&nbsp;&nbsp;录</a>
          <a class="gv" href="#">清&nbsp;&nbsp;空</a>
     </div>
  </div>
  <div class="canvaszz"> </div>
  <canvas id="canvas"></canvas> 
</div>
<script>
//宇宙特效
"use strict";
var canvas = document.getElementById('canvas'),
  ctx = canvas.getContext('2d'),
  w = canvas.width = window.innerWidth,
  h = canvas.height = window.innerHeight,
 
  hue = 217,
  stars = [],
  count = 0,
  maxStars = 2500;//星星数量
 
var canvas2 = document.createElement('canvas'),
  ctx2 = canvas2.getContext('2d');
canvas2.width = 100;
canvas2.height = 100;
var half = canvas2.width / 2,
  gradient2 = ctx2.createRadialGradient(half, half, 0, half, half, half);
gradient2.addColorStop(0.025, '#CCC');
gradient2.addColorStop(0.1, 'hsl(' + hue + ', 61%, 33%)');
gradient2.addColorStop(0.25, 'hsl(' + hue + ', 64%, 6%)');
gradient2.addColorStop(1, 'transparent');
 
ctx2.fillStyle = gradient2;
ctx2.beginPath();
ctx2.arc(half, half, half, 0, Math.PI * 2);
ctx2.fill();
 
// End cache
 
function random(min, max) {
  if (arguments.length < 2) {
    max = min;
    min = 0;
  }
 
  if (min > max) {
    var hold = max;
    max = min;
    min = hold;
  }
 
  return Math.floor(Math.random() * (max - min + 1)) + min;
}
 
function maxOrbit(x, y) {
  var max = Math.max(x, y),
    diameter = Math.round(Math.sqrt(max * max + max * max));
  return diameter / 2;
  //星星移动范围，值越大范围越小，
}
 
var Star = function() {
 
  this.orbitRadius = random(maxOrbit(w, h));
  this.radius = random(60, this.orbitRadius) / 18; 
  //星星大小
  this.orbitX = w / 2;
  this.orbitY = h / 2;
  this.timePassed = random(0, maxStars);
  this.speed = random(this.orbitRadius) / 500000; 
  //星星移动速度
  this.alpha = random(2, 10) / 10;
 
  count++;
  stars[count] = this;
}
 
Star.prototype.draw = function() {
  var x = Math.sin(this.timePassed) * this.orbitRadius + this.orbitX,
    y = Math.cos(this.timePassed) * this.orbitRadius + this.orbitY,
    twinkle = random(10);
 
  if (twinkle === 1 && this.alpha > 0) {
    this.alpha -= 0.05;
  } else if (twinkle === 2 && this.alpha < 1) {
    this.alpha += 0.05;
  }
 
  ctx.globalAlpha = this.alpha;
  ctx.drawImage(canvas2, x - this.radius / 2, y - this.radius / 2, this.radius, this.radius);
  this.timePassed += this.speed;
}
 
for (var i = 0; i < maxStars; i++) {
  new Star();
}
 
function animation() {
  ctx.globalCompositeOperation = 'source-over';
  ctx.globalAlpha = 0.5; //尾巴
  ctx.fillStyle = 'hsla(' + hue + ', 64%, 6%, 2)';
  ctx.fillRect(0, 0, w, h)
 
  ctx.globalCompositeOperation = 'lighter';
  for (var i = 1, l = stars.length; i < l; i++) {
    stars[i].draw();
  };
 
  window.requestAnimationFrame(animation);
}
 
animation();
</script>
 
</body>
</html>