@media (max-width: 768px) {
  .logo_header {
    height: 54px;
    width: auto;
  }
}

@media (max-width: 640px) {
  body {
    background-color: #f6f7f8;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
  }

  header {
    height: auto;
    padding: 16px;
    justify-content: flex-start;
  }

  .sign_up_box {
    width: 80%;
    min-height: auto;
    height: auto;
    max-width: 396px;
    margin: 20px auto;
    padding: 24px;
    border-radius: 30px;
    box-shadow: 0px 0px 14px 3px rgba(0, 0, 0, 0.04);
    overflow: visible;
    flex-direction: column;
  }

  .h1_div_sign_up_field {
    flex-direction: row;
    align-items: center;
    gap: 16px;
    width: 100%;
    min-height: auto;
    margin-bottom: 24px;
    padding-right: 24px;
  }

  .back_arrow_sign_in {
    padding-top: 8px;
    height: 24px;
    width: 24px;
    transform: translateX(-40px) scale(1);
    position: static;
  }

  .back_arrow_sign_in:hover {
    transform: translateX(-40px) scale(1.1);
  }

  .h1_box {
    font-size: 32px;
    margin: 0;
    text-align: left;
  }

  .input_div {
    width: 100%;
    height: auto;
  }

  .input_label {
    width: 100%;
    max-width: 100%;
  }

  .input_label input {
    font-size: 16px;
    height: 48px;
  }

  .input_icon {
    right: 16px;
    height: 16px;
    width: 16px;
  }

  .checkbox_div {
    display: flex;
    align-items: center;
    gap: 8px;
    margin: 16px 0;
    cursor: pointer;
  }

  .checkbox_div input[type="checkbox"] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    width: 18px;
    height: 18px;
    border: 2px solid #2a3647;
    border-radius: 4px;
    cursor: pointer;
    position: relative;
    flex-shrink: 0;
  }

  .checkbox_div input[type="checkbox"]:checked {
    background-color: #2a3647;
  }

  .checkbox_div input[type="checkbox"]:checked::after {
    content: "✓";
    color: white;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    font-size: 12px;
    font-weight: bold;
  }

  .checkbox_div label {
    color: #2a3647;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 4px;
  }

  .button_sign_up_input_section {
    height: 48px;
    font-size: 16px;
  }

  footer {
    height: auto;
    padding: 16px;
    flex-direction: row;
    gap: 16px;
  }
}