    @font-face {
      font-family: "Kosugi";
      src: url("fonts/Kosugi-Regular.woff2") format("woff2");
      font-weight: normal;
      font-style: normal;
      font-display: swap;
    }

    * {
      font-family: "Kosugi", monospace;
    }

    body {
      background-color: #FFFFFF;
      margin: 0;
      padding: 0 20px 20px;
      font-size: 14px;
      display: flex;
      justify-content: center;
    }

    .container {
      max-width: 960px;
      width: 100%;
    }

    .rounded-box {
      background-color: #E6E6E6;
      margin: 30px 0;
      border-radius: 8px;
      padding: 15px;
    }

    textarea {
      width: 100%;
      height: 150px;
      resize: vertical;
      box-sizing: border-box;
    }

    input[type="password"], input[type="text"] {
      width: 100%;
      box-sizing: border-box;
    }

    .password-box {
      background-color: #C0DAFA;
    }

    .encrypt-box {
      background-color: #C6FAC2;
    }

    .decrypt-box {
      background-color: #FAC2CC;
    }

    .section {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
    }

    .section > div {
      flex: 1 1 48%;
    }

    .text-center {
      text-align: center;
    }

    .footer {
      font-size: 12px;
      line-height: 1.5;
      margin-top: 30px;
    }

    @media (max-width: 600px) {
      .section {
        flex-direction: column;
      }

      .section > div {
        flex: 1 1 100%;
      }
    }