انشاء صفحة خطأ 404 لموقعك

<b:if cond='data:blog.pageType == &quot;error_page&quot;'>
<style>
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        position:fixed;
        top:0px;
        right:0px;
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        padding-top:270px;
        z-index:999999;
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#error-not-found  h1 {
        font-size:640px!important;
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        font-family:&#39;sultan_-_3_line_2sultan3line&#39;!important;
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        z-index:-2;
        color:rgba(0,0,0,.09)!important;
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#error-not-found  h2 {
        font-family:&#39;sultan_-_3_line_2sultan3line&#39;!important;
        text-transform:uppercase;
        font-size:81px;
        line-height:100px!important;
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        color:#fff!important;
        margin:0!important;
        padding:0!important;
}
#error-not-found p a,
#error-not-found p a:visited,
#error-not-found p a:hover{
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</style>
<div id='error-not-found'>
 <h1>404</h1> <h2>نعتذر منك..الصفحة غير موجودة</h2>
 <h2>كيف وصلت إلى هنا !</h2>
 <p> <a href='/' title='الرئيسية'> الرجوع لصفحة الرئيسية</a></p>
</div>
</b:if>