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• Dengan menggunakan ctrl + F, cari kode </body>
• Lalu letakkan kode berikut diatasnya 

<b:if cond='data:blog.pageType == &quot;error_page&quot;'>
<style>
/* CSS reset */body,div,dl,dt,dd,ul,ol,li,h1,h2,h3,h4,h5,h6,pre,form,fieldset,input,textarea,p,blockquote,th,td{margin:0;padding:0}
html,body{margin:0;padding:0;overflow:hidden;}
table{border-collapse:collapse;border-spacing:0}
fieldset,img{border:0}
input{border:1px solid #b0b0b0;padding:3px 5px 4px;color:#979797;width:190px}
address,caption,cite,code,dfn,th,var{font-style:normal;font-weight:normal}
ol,ul{list-style:none}
caption,th{text-align:left}
h1,h2,h3,h4,h5,h6{font-size:100%;font-weight:normal}
q:before,q:after{content:&#39;&#39;}
abbr,acronym{border:0}
#error-not-found{background:#310404 url(https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgaSkZtarw0rkdh8727lxSL5xl_ziJs6RpkwXFNqy5NSuWJQtUx-2iiCuD0pgxi1Ie_-w9G-gEOOV-Do4SwLCctOhPY15l15WY1HIV0_5AXkc6IGyj2zDeaJIwT0t-YF9sgDpj-02jGzNg/s1600/overlay.png) repeat;font-family:&#39;BebasNeueRegular&#39;;z-index:999999;position:fixed;top:0px;left:0px;width:100%;height:100%;z-index:999999;overflow:hidden;}
.eror-page{background:-webkit-radial-gradient(rgba(0,0,0,0.1),rgba(0,0,0,0.3) 35%,rgba(0,0,0,0.7));background:-moz-radial-gradient(rgba(0,0,0,0.1),rgba(0,0,0,0.3) 35%,rgba(0,0,0,0.7));background:-ms-radial-gradient(rgba(0,0,0,0.1),rgba(0,0,0,0.3) 35%,rgba(0,0,0,0.7));background:radial-gradient(rgba(0,0,0,0.1),rgba(0,0,0,0.3) 35%,rgba(0,0,0,0.7));position:absolute;width:100%;height:100%;left:0px;top:0px;z-index:1000}
#error-not-found h2{position:absolute;top:50%;line-height:100px;height:100px;margin-top:-50px;font-size:100px;width:100%;text-align:center;color:transparent;-webkit-animation:blurFadeInOut 3s ease-in backwards;-moz-animation:blurFadeInOut 3s ease-in backwards;-ms-animation:blurFadeInOut 3s ease-in backwards;animation:blurFadeInOut 3s ease-in backwards}
#error-not-found h2.frame-1{-webkit-animation-delay:0s;-moz-animation-delay:0s;-ms-animation-delay:0s;animation-delay:0s}
#error-not-found h2.frame-2{-webkit-animation-delay:3s;-moz-animation-delay:3s;-ms-animation-delay:3s;animation-delay:3s}
#error-not-found h2.frame-3{-webkit-animation-delay:6s;-moz-animation-delay:6s;-ms-animation-delay:6s;animation-delay:6s}
#error-not-found h2.frame-4{font-size:200px;-webkit-animation-delay:9s;-moz-animation-delay:9s;-ms-animation-delay:9s;animation-delay:9s}
#error-not-found h2.frame-5{-webkit-animation:none;-moz-animation:none;-ms-animation:none;animation:none;color:transparent;text-shadow:0px 0px 1px #fff}
#error-not-found h2.frame-5 span{-webkit-animation:blurFadeIn 3s ease-in 12s backwards;-moz-animation:blurFadeIn 1s ease-in 12s backwards;-ms-animation:blurFadeIn 3s ease-in 12s backwards;animation:blurFadeIn 3s ease-in 12s backwards;color:transparent;text-shadow:0px 0px 1px #fff}
#error-not-found h2.frame-5 span:nth-child(2){-webkit-animation-delay:13s;-moz-animation-delay:13s;-ms-animation-delay:13s;animation-delay:13s}
#error-not-found h2.frame-5 span:nth-child(3){-webkit-animation-delay:14s;-moz-animation-delay:14s;-ms-animation-delay:14s;animation-delay:14s}
.sp-backg{position:absolute;width:470px;height:239px;left:50%;top:50%;margin:-137px 0 0 -141px;background:transparent url(http://www.naturalhealthencyclopedia.com/skin/img/404.png) no-repeat top left;-webkit-animation:fadeInBack 3.6s linear 14s backwards;-moz-animation:fadeInBack 3.6s linear 14s backwards;-ms-animation:fadeInBack 3.6s linear 14s backwards;animation:fadeInBack 3.6s linear 14s backwards;-ms-filter:&quot;progid:DXImageTransform.Microsoft.Alpha(Opacity=30)&quot;;filter:alpha(opacity=30);opacity:0.3;-webkit-transform:scale(2);-moz-transform:scale(2);transform:scale(2)}
.sp-circle-link{position:absolute;left:50%;bottom:5%;margin-left:-50px;text-align:center;line-height:100px;width:100px;height:100px;background:#fff;color:#3f1616;font-size:25px;-webkit-border-radius:50%;-moz-border-radius:50%;border-radius:50%;-webkit-animation:fadeInRotate 1s linear 16s backwards;-moz-animation:fadeInRotate 1s linear 16s backwards;-ms-animation:fadeInRotate 1s linear 16s backwards;animation:fadeInRotate 1s linear 16s backwards;-webkit-transform:scale(0.8) rotate(0deg);-moz-transform:scale(0.8) rotate(0deg);transform:scale(0.8) rotate(0deg)}
.sp-circle-link:hover{background:#85373b;color:#fff}
/**/@-webkit-keyframes blurFadeInOut{0%{opacity:0;text-shadow:0px 0px 40px #fff;-webkit-transform:scale(1.3)}
20%,75%{opacity:1;text-shadow:0px 0px 1px #fff;-webkit-transform:scale(1)}
100%{opacity:0;text-shadow:0px 0px 50px #fff;-webkit-transform:scale(0)}
}
@-webkit-keyframes blurFadeIn{0%{opacity:0;text-shadow:0px 0px 40px #fff;-webkit-transform:scale(1.3)}
50%{opacity:0.5;text-shadow:0px 0px 10px #fff;-webkit-transform:scale(1.1)}
100%{opacity:1;text-shadow:0px 0px 1px #fff;-webkit-transform:scale(1)}
}
@-webkit-keyframes fadeInBack{0%{opacity:0;-webkit-transform:scale(0)}
50%{opacity:0.4;-webkit-transform:scale(1)}
100%{opacity:0.2;-webkit-transform:scale(2)}
}
@-webkit-keyframes fadeInRotate{0%{opacity:0;-webkit-transform:scale(0) rotate(360deg)}
100%{opacity:1;-webkit-transform:scale(1) rotate(0deg)}
}
/**/@-moz-keyframes blurFadeInOut{0%{opacity:0;text-shadow:0px 0px 40px #fff;-moz-transform:scale(1.3)}
20%,75%{opacity:1;text-shadow:0px 0px 1px #fff;-moz-transform:scale(1)}
100%{opacity:0;text-shadow:0px 0px 50px #fff;-moz-transform:scale(0)}
}
@-moz-keyframes blurFadeIn{0%{opacity:0;text-shadow:0px 0px 40px #fff;-moz-transform:scale(1.3)}
100%{opacity:1;text-shadow:0px 0px 1px #fff;-moz-transform:scale(1)}
}
@-moz-keyframes fadeInBack{0%{opacity:0;-moz-transform:scale(0)}
50%{opacity:0.4;-moz-transform:scale(1)}
100%{opacity:0.2;-moz-transform:scale(2)}
}
@-moz-keyframes fadeInRotate{0%{opacity:0;-moz-transform:scale(0) rotate(360deg)}
100%{opacity:1;-moz-transform:scale(1) rotate(0deg)}
}
/**/@keyframes blurFadeInOut{0%{opacity:0;text-shadow:0px 0px 40px #fff;transform:scale(1.3)}
20%,75%{opacity:1;text-shadow:0px 0px 1px #fff;transform:scale(1)}
100%{opacity:0;text-shadow:0px 0px 50px #fff;transform:scale(0)}
}
@keyframes blurFadeIn{0%{opacity:0;text-shadow:0px 0px 40px #fff;transform:scale(1.3)}
50%{opacity:0.5;text-shadow:0px 0px 10px #fff;transform:scale(1.1)}
100%{opacity:1;text-shadow:0px 0px 1px #fff;transform:scale(1)}
}
@keyframes fadeInBack{0%{opacity:0;transform:scale(0)}
50%{opacity:0.4;transform:scale(1)}
100%{opacity:0.2;transform:scale(2)}
}
@keyframes fadeInRotate{0%{opacity:0;transform:scale(0) rotate(360deg)}
100%{opacity:1;transform:scale(1) rotate(0deg)}
}
</style>
<div class='container'>
<div id='error-not-found'>
<div class='eror-page'>
<div class='sp-backg'/>
<h2 class='frame-1'>Mohon Maaf..!!!</h2>
<h2 class='frame-2'>Halaman Yang Anda Cari Tidak Ada</h2>
<h2 class='frame-3'>Go To Homepage</h2>
<h2 class='frame-4'>Now... !!</h2>
<h2 class='frame-5'><span>Error 404.!!</span> <span>Page Not</span> <span>Found.</span></h2>
<a class='sp-circle-link' expr:href='data:blog.homepageUrl' title='Home page'>HOME</a>
</div>
</div></div> <!-- end-->
</b:if>

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