<style>
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: Arial, Helvetica, sans-serif;
      background: linear-gradient(135deg, #e8f5e9, #f1f8e9);
      color: #1f2933;
      line-height: 1.6;
    }

    header {
      background: linear-gradient(135deg, #14532d, #22c55e);
      color: white;
      text-align: center;
      padding: 50px 20px;
    }

    header h1 {
      font-size: 2.4rem;
      margin-bottom: 10px;
    }

    header p {
      font-size: 1.1rem;
      max-width: 900px;
      margin: 0 auto;
    }

    main {
      width: 90%;
      max-width: 1100px;
      margin: 30px auto;
    }

    section {
      background: white;
      margin-bottom: 25px;
      padding: 28px;
      border-radius: 18px;
      box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
      border-left: 8px solid #22c55e;
    }

    h2 {
      color: #14532d;
      margin-bottom: 15px;
      font-size: 1.8rem;
    }

    h3 {
      color: #166534;
      margin: 20px 0 10px;
    }

    p {
      margin-bottom: 12px;
      font-size: 1.05rem;
    }

    ul {
      margin-left: 25px;
      margin-bottom: 15px;
    }

    li {
      margin-bottom: 8px;
    }

    .destaque {
      background: #dcfce7;
      border-left: 5px solid #16a34a;
      padding: 15px;
      border-radius: 10px;
      margin: 18px 0;
    }

    .cards {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
      gap: 18px;
      margin-top: 20px;
    }

    .card {
      background: #f0fdf4;
      border: 1px solid #bbf7d0;
      border-radius: 14px;
      padding: 18px;
      transition: 0.3s;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: 0 8px 18px rgba(0, 0, 0, 0.1);
    }

    .card h3 {
      margin-top: 0;
      color: #14532d;
    }

    pre {
      background: #111827;
      color: #e5e7eb;
      padding: 18px;
      border-radius: 12px;
      overflow-x: auto;
      font-size: 0.95rem;
      margin: 18px 0;
    }

    code {
      font-family: Consolas, Monaco, monospace;
    }

    .btn {
      background: #16a34a;
      color: white;
      border: none;
      padding: 12px 18px;
      border-radius: 10px;
      cursor: pointer;
      font-size: 1rem;
      margin-top: 10px;
      transition: 0.3s;
    }

    .btn:hover {
      background: #15803d;
    }

    .resultado {
      margin-top: 15px;
      background: #f0fdf4;
      border: 1px solid #86efac;
      padding: 15px;
      border-radius: 10px;
      display: none;
    }

    .exercicio {
      background: #fffbeb;
      border-left-color: #f59e0b;
    }

    .exercicio h2 {
      color: #92400e;
    }

    label {
      font-weight: bold;
      display: block;
      margin-top: 15px;
      margin-bottom: 6px;
    }

    input, textarea {
      width: 100%;
      padding: 12px;
      border: 1px solid #d1d5db;
      border-radius: 10px;
      font-size: 1rem;
    }

    textarea {
      min-height: 90px;
      resize: vertical;
    }

    .resposta-aluno {
      margin-top: 20px;
      background: white;
      padding: 18px;
      border-radius: 12px;
      border: 1px solid #fcd34d;
      display: none;
    }

    footer {
      text-align: center;
      padding: 25px;
      background: #14532d;
      color: white;
      margin-top: 40px;
    }

    @media (max-width: 700px) {
      header h1 {
        font-size: 1.8rem;
      }

      section {
        padding: 20px;
      }

      h2 {
        font-size: 1.5rem;
      }
    }
  </style>