body {
    font-family: "Hiragino Kaku Gothic ProN", sans-serif;
    background: #f6f6f6;
    margin: 0;
  }
  a{
    text-decoration: none;
    color: #000000;
  
  }
  a:active {
    color: #000000;
  }
  a:focus {
    outline: none;
  }
  header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 30px;
    background: #fff;
    border-bottom: 1px solid #ddd;
  }
  
  .logo-green { color: #9cd43f; font-weight: bold; }
  .logo-black { color: #333; font-weight: bold; }
  
  .search-area {
    display: flex;
    align-items: center;
    gap: 10px;
  }
  
  .search-area input {
    width: 250px;
    padding: 8px 12px;
    border: 2px solid #ddd;
    border-radius: 20px;
    font-size: 14px;
  }
  
  .login-btn,
  .signup-btn,.logout-btn,.write-btn {
    padding: 6px 15px;
    border: 1px solid #ccc;
    border-radius: 10px;
    background: #f9f9f9;
    cursor: pointer;
  }
  
  .signup-btn {
    border-color: #a8d8ff;
    background: #e8f4ff;
  }
  .logout-btn {
    border-color:#ffa8a8 ;
    background: #ffe8e8;
  }
  .write-btn {
    border-color:#a8ffa8;
    background: #e8ffe8;
  }
  
  main {
    display: flex;
    max-width: 1300px;
    margin: 20px auto;
    gap: 20px;
  }
  
  .sidebar {
    width: 220px;
    background: #fff;
    padding: 15px;
    border-right: 1px solid #ddd;
  }
  
  .sidebar h2 {
    font-size: 16px;
    margin-bottom: 10px;
    border-bottom: 1px solid #ddd;
    padding-bottom: 5px;
  }
  
  .sidebar ul {
    list-style: none;
    padding: 0;
    margin: 0;
  }
  
  .sidebar li { margin: 6px 0; }
  
  .sidebar a {
    text-decoration: none;
    color: #0074cc;
    font-size: 14px;
  }
  
  .sidebar a:hover {
    text-decoration: underline;
  }
  
  /* ====== 記事部分 ====== */
  .post {
    flex: 1;
    background: #fff;
    padding: 30px 40px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
  }
  
  .post h2 {
    font-size: 24px;
    color: #222;
    margin-bottom: 5px;
  }
  
  .meta {
    color: #777;
    font-size: 13px;
    margin-bottom: 20px;
  }
  
  .content h3 {
    margin-top: 25px;
    color: #333;
    border-left: 4px solid #9cd43f;
    padding-left: 10px;
  }
  
  .content p {
    line-height: 1.8;
    color: #444;
  }
  
  .content ul {
    padding-left: 20px;
  }
  
  pre {
    background: #272822;
    color: #f8f8f2;
    padding: 15px;
    border-radius: 6px;
    overflow-x: auto;
  }
  
  code {
    font-family: Consolas, monospace;
  }
  
  .article-image {
    max-width: 100%;
    margin: 15px 0;
    border-radius: 5px;
    border: 1px solid #ccc;
  }
  .con-body{
    width:923px;
    height: 780px;
  }
  .summary-body{
    width:923px;
    height: 100px;
  }