body {
      background: #f0f2f5;
      min-height: 100vh;
      font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    }
     .content { margin-left: 230px; padding: 2rem; }
    .sidebar {
      height: 100vh;
      width: 220px;
      position: fixed;
      background: #222f3e;
      color: #eee;
      padding: 2rem 1rem;
      box-shadow: 4px 0 10px rgba(0,0,0,0.1);
    }
    .sidebar h4 {
      font-weight: 700;
      margin-bottom: 2rem;
      letter-spacing: 1.2px;
    }
    .sidebar a {
      color: #bbb;
      text-decoration: none;
      display: block;
      margin-bottom: 1.2rem;
      padding: 0.4rem 0.6rem;
      border-radius: 5px;
      transition: all 0.3s ease;
      font-weight: 500;
    }
    .sidebar a.active,
    .sidebar a:hover {
      background: #576574;
      color: #fff;
      font-weight: 600;
      box-shadow: inset 3px 0 0 #70a1ff;
    }
   main {
    margin-left: 240px;
    padding: 3rem 2rem;
    max-width: 100%;
    background: #fff;
    margin-top: 40px;
    margin-bottom: 40px;
    border-radius: 15px;
    box-shadow: 0 12px 25px rgba(100, 100, 111, 0.2);
    width: 100%;
    margin-right: 25px;
}
    h2 {
      font-weight: 700;
      margin-bottom: 2rem;
      color: #222f3e;
      letter-spacing: 1.1px;
      
    }
    label {
      font-weight: 600;
      color: #222f3e;
    }
    .form-control {
      border-radius: 12px;
      box-shadow: none !important;
      border: 1.8px solid #ced6e0;
      font-size: 1.1rem;
      padding: 0.75rem 1rem;
      transition: border-color 0.3s ease;
    }
    .form-control:focus {
      border-color: #70a1ff;
      box-shadow: 0 0 6px #70a1ffaa !important;
      outline: none;
    }
    .form-check-label {
      font-weight: 500;
      color: #576574;
      font-size: 1rem;
    }
    button.btn-primary {
      background: #70a1ff;
      border: none;
      font-weight: 600;
      padding: 0.75rem 1.5rem;
      border-radius: 12px;
      box-shadow: 0 6px 15px #70a1ff80;
      transition: background 0.3s ease;
      width: 100%;
      font-size: 1.15rem;
    }
    button.btn-primary:hover {
      background: #4c8eff;
      box-shadow: 0 8px 20px #4c8effaa;
    }
    a.btn-secondary {
      margin-top: 1rem;
      display: inline-block;
      width: 100%;
      text-align: center;
      padding: 0.75rem 1rem;
      font-weight: 600;
      font-size: 1.1rem;
      border-radius: 12px;
      color: #576574;
      background: #f1f2f6;
      border: none;
      text-decoration: none;
      box-shadow: 0 4px 12px #ced6e0;
      transition: background 0.3s ease;
    }
    a.btn-secondary:hover {
      background: #d1d8e0;
      color: #2f3542;
    }
    .alert {
      border-radius: 12px;
      font-size: 1rem;
      padding: 1rem 1.25rem;
    }