/* ===== RESET ===== */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
      font-family: "Poppins", sans-serif;
    }

    body {
      background: radial-gradient(circle at top, #0a0f18 0%, #0d1117 100%);
      color: #e6edf3;
      overflow-x: hidden;
      min-height: 100vh;
    }

    /* ===== BUTTON HOME ===== */
    .home-btn {
      position: fixed;
      top: 25px;
      left: 25px;
      background: linear-gradient(90deg, #00bfff, #007bff);
      color: #fff;
      padding: 10px 20px;
      border: none;
      border-radius: 8px;
      cursor: pointer;
      text-decoration: none;
      font-weight: 500;
      box-shadow: 0 0 15px rgba(0, 191, 255, 0.5);
      transition: 0.3s;
      z-index: 10;
    }

    .home-btn:hover {
      transform: scale(1.05);
      box-shadow: 0 0 25px rgba(0, 191, 255, 0.8);
    }

    /* ===== PROFILE SECTION (CŨ) ===== */
    .profile {
      display: flex;
      justify-content: center;
      align-items: center;
      flex-wrap: wrap;
      padding: 120px 20px 60px;
      gap: 50px;
      text-align: center;
    }

    .avatar img {
      width: 220px;
      height: 220px;
      border-radius: 50%;
      object-fit: cover;
      border: 4px solid #00bfff;
      box-shadow: 0 0 25px rgba(0, 191, 255, 0.4);
      animation: glowPulse 4s infinite alternate;
    }

    @keyframes glowPulse {
      from { box-shadow: 0 0 15px #00bfff; }
      to { box-shadow: 0 0 40px #00bfff; }
    }

    .info h1 {
      font-size: 38px;
      color: #00bfff;
      margin-bottom: 10px;
      text-shadow: 0 0 15px #00bfff;
    }

    .info p {
      margin: 5px 0;
      font-size: 16px;
      color: #c9d1d9;
    }

    .bio {
      margin-top: 15px;
      line-height: 1.6;
      max-width: 500px;
      color: #b3c0ce;
    }

    /* ===== MỤC TIÊU VÀ SỞ THÍCH (CẬP NHẬT LAYOUT 2 CỘT) ===== */
    .details {
      display: flex;
      justify-content: space-between;
      gap: 40px;
      padding: 60px 20px;
      flex-wrap: wrap;
    }

    .card {
      background: #161b22;
      padding: 30px;
      border-radius: 16px;
      width: 48%;
      box-shadow: 0 0 20px rgba(0, 191, 255, 0.1);
      border: 1px solid rgba(0, 191, 255, 0.1);
      transition: 0.3s;
    }

    .card:hover {
      transform: translateY(-8px);
      box-shadow: 0 0 25px rgba(0, 191, 255, 0.3);
    }

    .card h2 {
      color: #00bfff;
      margin-bottom: 15px;
      text-shadow: 0 0 10px #00bfff;
      font-size: 22px;
    }

    .card ul {
      list-style: none;
    }

    .card ul li {
      margin-bottom: 10px;
      color: #b3c0ce;
    }

    /* ===== KỸ NĂNG (CẬP NHẬT LAYOUT 2 CỘT) ===== */
    .skills {
      text-align: center;
      padding: 60px 20px;
    }

    .skills h2 {
      font-size: 28px;
      color: #00bfff;
      margin-bottom: 20px;
      text-shadow: 0 0 10px #00bfff;
    }

    .skill {
      margin-bottom: 20px;
    }

    .skill p {
      margin-bottom: 5px;
      color: #b3c0ce;
    }

    .skill-bar {
      width: 80%;
      max-width: 500px;
      margin: 0 auto;
      background: #111;
      border-radius: 10px;
      overflow: hidden;
    }

    .skill-fill {
      height: 12px;
      background: linear-gradient(90deg, #00bfff, #007bff);
      width: 0;
      border-radius: 10px;
      transition: 1s ease;
    }

    /* ===== CONTACT FORM ===== */
    .contact {
      text-align: center;
      padding: 40px 20px 100px;
    }

    .contact h2 {
      font-size: 28px;
      color: #00bfff;
      margin-bottom: 25px;
      text-shadow: 0 0 10px #00bfff;
    }

    form {
      background: #161b22;
      border-radius: 16px;
      padding: 30px;
      max-width: 450px;
      margin: 0 auto;
      box-shadow: 0 0 25px rgba(0, 191, 255, 0.1);
      border: 1px solid rgba(0, 191, 255, 0.1);
    }

    .form-group {
      margin-bottom: 20px;
      text-align: left;
    }

    label {
      display: block;
      margin-bottom: 6px;
      font-weight: 500;
      color: #e6edf3;
    }

    input, textarea {
      width: 100%;
      padding: 10px 12px;
      background: #0d1117;
      border: 1px solid #00bfff;
      border-radius: 8px;
      color: #fff;
      font-size: 15px;
      outline: none;
      transition: 0.3s;
    }

    input:focus, textarea:focus {
      box-shadow: 0 0 15px rgba(0, 191, 255, 0.6);
    }

    textarea {
      resize: none;
      height: 100px;
    }

    .btn-submit {
      background: linear-gradient(90deg, #00bfff, #007bff);
      color: #fff;
      border: none;
      padding: 10px 25px;
      border-radius: 8px;
      font-size: 16px;
      cursor: pointer;
      transition: 0.3s;
      width: 100%;
      box-shadow: 0 0 15px rgba(0, 191, 255, 0.4);
    }

    .btn-submit:hover {
      transform: scale(1.05);
      box-shadow: 0 0 25px rgba(0, 191, 255, 0.7);
    }

    /* ===== SUCCESS POPUP ===== */
    .popup {
      display: none;
      position: fixed;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      background: #161b22;
      color: #e6edf3;
      padding: 30px 50px;
      border-radius: 12px;
      text-align: center;
      box-shadow: 0 0 40px rgba(0, 191, 255, 0.4);
      border: 1px solid rgba(0, 191, 255, 0.3);
      z-index: 999;
      animation: fadeIn 0.4s ease;
    }

    @keyframes fadeIn {
      from { opacity: 0; transform: translate(-50%, -60%); }
      to { opacity: 1; transform: translate(-50%, -50%); }
    }

    .popup h3 {
      color: #00bfff;
      margin-bottom: 10px;
      text-shadow: 0 0 10px #00bfff;
    }

    .popup button {
      margin-top: 15px;
      padding: 8px 20px;
      border: none;
      border-radius: 6px;
      background: linear-gradient(90deg, #00bfff, #007bff);
      color: #fff;
      cursor: pointer;
      transition: 0.3s;
    }

    .popup button:hover {
      transform: scale(1.05);
      box-shadow: 0 0 15px rgba(0, 191, 255, 0.6);
    }
        /* ===== MEDIA (ẢNH, VIDEO, AUDIO) ===== */
    .card img {
      width: 100%;
      border-radius: 12px;
      margin-top: 15px;
      border: 1px solid rgba(0, 191, 255, 0.3);
      box-shadow: 0 0 20px rgba(0, 191, 255, 0.2);
      transition: 0.4s;
      object-fit: cover;
    }

    .card img:hover {
      transform: scale(1.03);
      box-shadow: 0 0 30px rgba(0, 191, 255, 0.5);
    }

    .card video {
      width: 100%;
      margin-top: 15px;
      border-radius: 12px;
      border: 1px solid rgba(0, 191, 255, 0.3);
      box-shadow: 0 0 25px rgba(0, 191, 255, 0.2);
      transition: 0.4s;
    }

    .card video:hover {
      transform: scale(1.02);
      box-shadow: 0 0 30px rgba(0, 191, 255, 0.6);
    }

    .card audio {
      width: 100%;
      margin-top: 15px;
      filter: drop-shadow(0 0 15px rgba(0, 191, 255, 0.4));
      border-radius: 8px;
    }

    /* Tùy chỉnh thanh điều khiển audio (webkit browsers) */
    audio::-webkit-media-controls-panel {
      background: #0d1117;
      border-radius: 8px;
    }
    audio::-webkit-media-controls-play-button {
      filter: invert(70%) sepia(100%) saturate(300%) hue-rotate(180deg);
    }
    audio::-webkit-media-controls-volume-slider {
      filter: invert(70%) sepia(100%) saturate(300%) hue-rotate(180deg);
    }