* {
    box-sizing: border-box;
  }
  
  :root {
    /* Cores principais */
    --primary-bg: #1f2937;
    --secondary-bg: #111827;
    --text-primary: #f3f4f6;
    --text-secondary: #e5e7eb;
    --accent: #06b6d4;
    --accent-hover: #0891b2;
    --border-accent: #06b6d4;
    --shadow-color: rgba(0, 0, 0, 0.3);
  
    /* Fontes */
    --font-family: 'Fira Code', monospace;
  }
  
  body {
    font-family: var(--font-family);
    background-color: var(--secondary-bg);
    color: var(--text-primary);
    padding-top: 64px;
  }
  
  /* Header */
  header {
    background-color: rgba(31, 41, 55, 0.8);
    box-shadow: 0 2px 4px var(--shadow-color);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 50;
  }
  
  header h1, .nav-link {
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
  }
  
  header h1 img {
    width: 2rem;
    height: 2rem;
  }
  
  /* Estilo para a foto na seção Hero */
  .profile-pic {
    width: 200px;
    height: 200px;
    max-width: 80%;
    object-fit: cover;
    border-radius: 50%;
    border: 3px solid var(--border-accent);
    box-shadow: 0 4px 6px var(--shadow-color);
    margin: 0 auto 1.5rem;
  }
  
  @media (max-width: 640px) {
    .profile-pic {
      width: 150px;
      height: 150px;
    }
  }
  
  /* Hero Section */
  .hero-section {
    background: linear-gradient(to bottom, var(--primary-bg), var(--secondary-bg));
  }
  
  /* Botão "Ver meus projetos" */
  .hero-button {
    background-color: var(--accent);
    color: #fff;
    padding: 0.75rem 1.5rem;
    border-radius: 0.75rem;
    font-weight: 500;
    transition: background-color 0.3s ease;
  }
  
  .hero-button:hover {
    background-color: var(--accent-hover);
  }
  
  @media (max-width: 640px) {
    .hero-button {
      padding: 0.5rem 1rem;
      font-size: 0.875rem;
    }
  }
  
  /* Seções */
  section {
    padding: 4rem 1.5rem;
    opacity: 1 !important;
    min-height: 200px;
    scroll-margin-top: 20px;
  }
  
  @media (max-width: 768px) {
    section {
      padding: 2rem 1rem;
    }
  }
  
  .section-title {
    font-size: 1.875rem;
    font-weight: 600;
    margin-bottom: 2.5rem;
    border-bottom: 2px solid var(--accent);
    padding-bottom: 0.5rem;
  }
  
  /* Habilidades e Projetos */
  .bg-section-alt {
    background-color: var(--primary-bg);
  }
  
  .card {
    background-color: var(--primary-bg);
    padding: 1.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 2px 4px var(--shadow-color);
  }
  
  @media (max-width: 640px) {
    .card {
      padding: 1rem;
    }
  }
  
  /* Estilo para imagens de projeto com transição ao passar o mouse */
  .project-image {
    width: 100%;
    border-radius: 0.5rem;
    margin-bottom: 1rem;
    transition: transform 0.3s ease, filter 0.3s ease;
  }
  
  .project-image:hover {
    transform: scale(1.05);
    filter: brightness(1.1);
  }
  
  /* Links de navegação e GitHub */
  .nav-link, .hero-button, .github-link, .contact-link {
    transition: all 0.3s ease;
  }
  
  .nav-link {
    color: var(--text-primary);
  }
  
  .nav-link:hover {
    color: var(--accent);
  }
  
  .github-link {
    color: var(--accent);
    text-decoration: none;
  }
  
  .github-link:hover {
    text-decoration: underline;
  }
  
  /* Menu responsivo */
  .nav-menu {
    font-size: 1rem;
  }
  
  @media (min-width: 768px) {
    .nav-menu {
      display: flex;
      space-x-4;
    }
  }
  
  .menu-toggle {
    display: none;
  }
  
  .menu-toggle svg {
    width: 1.5rem;
    height: 1.5rem;
  }
  
  @media (max-width: 768px) {
    .menu-toggle {
      display: block;
      padding: 0.5rem;
    }
    .menu-toggle svg {
      width: 2rem;
      height: 2rem;
    }
    .nav-menu {
      display: none;
      flex-direction: column;
      position: absolute;
      top: 100%;
      left: 0;
      width: 100%;
      background-color: var(--primary-bg);
      padding: 1rem;
    }
    .nav-menu.active {
      display: flex;
    }
    .nav-menu a {
      padding: 0.5rem 0;
      text-align: center;
      font-size: 0.9rem;
    }
  }
  
  /* Contato */
  .contact-link {
    color: var(--accent);
    text-decoration: none;
  }
  
  .contact-link:hover {
    text-decoration: underline;
  }
  
  /* Footer */
  footer {
    background-color: var(--secondary-bg);
    border-top: 1px solid #374151;
    color: var(--text-secondary);
    padding: 1.5rem 0;
    text-align: center;
  }
  
  /* Botão Voltar ao Topo */
  .back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background-color: var(--accent);
    color: #fff;
    padding: 0.75rem;
    border-radius: 50%;
    display: none;
    transition: opacity 0.3s ease;
    z-index: 100;
  }
  
  @media (max-width: 640px) {
    .back-to-top {
      padding: 1rem;
      bottom: 1rem;
      right: 1rem;
    }
    .back-to-top svg {
      width: 1.5rem;
      height: 1.5rem;
    }
  }
  
  .back-to-top.visible {
    display: block;
    opacity: 1;
  }