/* پایه */
    body {
      font-family: 'Vazirmatn', sans-serif;
      margin: 0;
      background-color: #0A1931;
      color: #EAF4F4;
      direction: rtl;
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-direction: column;
      position: relative;
      overflow-x: hidden;
    }

    /* حباب‌های پس‌زمینه */
    .bubbles {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      overflow: hidden;
      z-index: 0;
    }

    .bubble {
      position: absolute;
      bottom: -150px;
      background: rgba(74, 144, 226, 0.1);
      border-radius: 50%;
      animation: rise 20s infinite ease-in;
    }

    .bubble:nth-child(1) { left: 10%; width: 30px; height: 30px; animation-duration: 18s; }
    .bubble:nth-child(2) { left: 25%; width: 50px; height: 50px; animation-duration: 22s; }
    .bubble:nth-child(3) { left: 50%; width: 20px; height: 20px; animation-duration: 16s; }
    .bubble:nth-child(4) { left: 70%; width: 60px; height: 60px; animation-duration: 26s; }
    .bubble:nth-child(5) { left: 85%; width: 40px; height: 40px; animation-duration: 20s; }

    @keyframes rise {
      0% { transform: translateY(0) scale(1); opacity: 0.3; }
      50% { opacity: 0.7; }
      100% { transform: translateY(-1200px) scale(1.3); opacity: 0; }
    }

    /* کارت ثبت‌نام */
    .register-card {
      background-color: #1A345B;
      border: 1px solid rgba(74, 144, 226, 0.2);
      border-radius: 25px;
      padding: 40px;
      width: 360px;
      max-width: 90%;
      min-height: 360px;
      box-shadow: 0 0 30px rgba(0, 0, 0, 0.4);
      text-align: center;
      z-index: 2;
      margin: 50px 0;
    }

    .register-card h2 {
      margin-bottom: 15px;
      color: #EAF4F4;
      text-shadow: 0 0 8px rgba(74, 144, 226, 0.4);
    }

    .register-card p {
      color: #BFD7EA;
      margin-bottom: 20px;
      font-size: 0.9rem;
    }

    form {
      display: flex;
      flex-direction: column;
      gap: 12px;
      align-items: center;
      width: 100%;
    }

    input {
      width: 90%;
      padding: 10px;
      border-radius: 10px;
      border: none;
      background-color: #26436E;
      color: #EAF4F4;
      font-size: 1em;
    }

    input::placeholder {
      color: #BFD7EA;
    }

    button {
      background-color: #4A90E2;
      color: #0A1931;
      border: none;
      border-radius: 10px;
      padding: 10px 0;
      font-weight: bold;
      width: 90%;
      cursor: pointer;
      transition: all 0.3s;
      box-shadow: 0 4px 12px rgba(74, 144, 226, 0.4);
    }

    button:hover {
      background-color: #5EA0FF;
      transform: translateY(-2px);
    }

    .login-link {
      margin-top: 15px;
      color: #EAF4F4;
      text-decoration: none;
      font-weight: 600;
      transition: color 0.3s;
      display: inline-block;
    }

    .login-link:hover {
      color: #4A90E2;
    }

    /* ریسپانسیو */
    @media (max-width: 480px) {
      body {
        align-items: flex-start;
        justify-content: flex-start;
        padding-top: 40px;
      }

      .register-card {
        width: 90%;
        padding: 25px 20px;
        border-radius: 20px;
        margin: 20px auto;
      }

      .register-card h2 {
        font-size: 1.3rem;
      }

      .register-card p {
        font-size: 0.85rem;
      }

      button {
        font-size: 0.95rem;
      }
    }