html,css,bootstrap

请问谁能告诉我一下问题出在哪里了？
它本来应该是

img

这样的，现在却是

img

这样的。求解

这是base.html


```html
{% load bootstrap4 %}

html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1,
    shrink-to-fit=no">
  <title>
      {% block title %}
        Blog
      {% endblock title %}
  title>

  <title>Blogtitle>
head>
<body>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" />
  <nav class="navbar navbar-expand-md navbar-light bg-light mb-4 border">
    <a class="navbar-brand" href="{% url 'blogs:index' %}">
        Home pagea>
    <button class="navbar-toggler" type="button" data-toggle="collapse"
        data-target="#navbarCollapse" aria-controls="navbarCollapse"
        aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon">span>button>
    <div class="collapse navbar-collapse" id="navbarCollapse">
      <ul class="navbar-nav mr-auto">
        <li class="nav-item">
          <a class="nav-link" href="{% url 'blogs:title_and_entry' %}">
              Blog homea>
        li>
        <li class="nav-item">
          <a class="nav-link" href="{% url 'blogs:category_list' %}">
              Categorya>
        li>
      ul>

      
      <ul class="navbar-nav ml-auto">
          {% if user.is_authenticated %}
            <li class="nav-item">
              <span class="navbar-text">Hello, {{ user.username }}span>
            li>
            <li class="nav-item">
              <a class="nav-link" href="{% url 'users:logout' %}">Log outa>
            li>
          {% else %}
            <li class="nav-item">
              <a class="nav-link" href="{% url 'users:register' %}">Registera>
            li>
            <li>
              <a class="nav-link" href="{% url 'users:login' %}">Logina>
            li>
          {% endif %}
      ul>
    div>
  nav>
  <main role="main" class="container">
    <div class="pb-2 mb-2 border-bottom">
      {% block page_header %}{% endblock page_header %}
    div>
      {% block content %}{% endblock content %}
  main>
body>
html>



这是category_list.html

{% extends 'blogs/base.html' %}



{% block page_header %}
    <h1 class="display-3">
        Category
    h1>
{% endblock page_header %}

{% block content %}
    html>
<html>
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <title>title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="category_list.css">

head>
<body>
    <ul class="container">
        <li class="text">
            <a href="#">
                <span>Lifespan>
            a>

        li>
        <li>
            <a href="#">
                <span>Entertainmentspan>
            a>

        li>
        <li>
            <a href="#">
                <span>Sportspan>
            a>

        li>
        <li>
            <a href="#">
                <span>Programmingspan>
            a>

        li>
        <li>
            <a href="#">
                <span>Learningspan>
            a>

        li>
    ul>
    body>
html>
{% endblock content %}





这是category.css

```css

*{
    margin: 0;
    padding: 0;
}

body{
    background: #CCC;
    font-family: "Robot",sans-serif;
}

ul{
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%,-50%);
    display: flex;
    margin: 0;
    padding: 0;
}

ul li{
    list-style: none;
    margin: 0 5px;
}

ul li a span{
    padding: 0;
    margin: 0 auto;
    position: absolute;
    top: 20px;
    color: #333;
    letter-spacing: 4px;
    transition: .5s;
    font-size: large;
    text-align: center;
    display: inline-block;
    width: 190px;
}

ul li a{
    text-decoration: none;
    display: block;
    width: 200px;
    height: 30px;
    background: #fff;
    text-align: left;
    padding: 20px;
    transform: rotate(-30deg) skewX(25deg) translate(0,0);
    transition: .5s;
    box-shadow: -20px 20px 10px rgb(0,0,0,0.5)
}

ul li a::before{
    content: '';
    position: absolute;
    top: 10px;
    left: -20px;
    height: 100%;
    width: 20px;
    background: #b1b1b1;
    transition: 0s;
    transform: rotate(0deg) skewY(-45deg);
}

ul li a::after{
    content: '';
    position: absolute;
    bottom: -20px;
    left: -10px;
    height: 20px;
    width: 100%;
    background: #b1b1b1;
    transition: 0s;
    transform: rotate(0deg) skewx(-45deg);
}

ul li a:hover{
    transform: rotate(-30deg) skew(25deg) translate(20px,-15px);
    box-shadow: -50px 50px 50px rgb(0,0,0,0.5);
}

ul li:hover span{
    color: #fff;
}

ul li:hover a{
    background-image: linear-gradient(to right,rgba(0, 64, 255, 0.807),rgb(8, 238, 177));
}

ul li:hover a::before{
    background: rgba(0, 64, 255, 0.807)
}

ul li:hover a::after{
    background-image: linear-gradient(to right,rgba(0, 64, 255, 0.807),rgb(8, 238, 177));
}



h1{
    position: absolute;
    top:10px;
    left: 50%;
    margin: 0;
    padding: 0;
    transform: translate(-50%);
    font-size: 4rem;
    width: 1ch;
    overflow: hidden;
    animation: 1s typing forwards;
}


@keyframes typing{
    from{
        width: 1ch;
    }

    to{
        width: 8ch;
    }
}

看看是不是因为没有写对css文件位置

link标签引入css文件的问题，查看1.link代码编写的位置（要写在head内，base.html写在了body里），2.css文件的路径是否正确