.converter {
    max-width: 700px;
    margin: 0 auto 40px auto;
  }
  
  .copy {
    font-size: 14px;
    color: #555;
    margin-bottom: 12px;
  }

  .segmented {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 6px;
    margin-bottom: 14px;
  }
  .seg-btn {
    padding: 8px 10px;
    font-size: 14px;
    border: 2px solid #d7e2fa;
    border-radius: 8px;
    background: #fff;
    cursor: pointer;
  }
  .seg-btn.active { background: #d7e2fa; }

  .row-layout {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 14px;
  }
  .label {
    font-weight: bold;
    margin-right: 4px;
    width: 220px;
    text-align: right;
  }
  input[type="number"], select {
    width: 200px;
    padding: 6px 10px;
    font-size: 18px;
    text-align: center;
    border: 2px solid #d7e2fa;
    border-radius: 6px;
    box-sizing: border-box;
  }

  .hint {
    font-size: 12px;
    color: #666;
    margin-top: -6px;
    text-align: center;
  }

  .result-layout {
    display: grid;
    grid-template-columns: auto auto;
    align-items: center;
    justify-content: center;
    gap: 10px 12px;
    width: 100%;
    margin-top: 10px;
  }
  .result-label {
    font-weight: bold;
    width: 130px;
    text-align: right;
  }
  .result-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    border: 2px solid #4caf50;
    border-radius: 6px;
    background: #f1f8e9;
    padding: 8px;
    color: #2e7d32;
    font-size: 16px;
    width: 240px;
    position: relative;
  }
  .copy-button {
    margin-left: 10px;
    padding: 6px 10px;
    font-size: 13px;
    cursor: pointer;
    background: #eeeeee;
    border: 2px solid #cccccc;
    border-radius: 6px;
    white-space: nowrap;
  }
  .copy-button:hover { background: #d7e2fa; }

  .copied-msg {
    position: absolute;
    right: 90px;
    top: 50%;
    transform: translateY(-50%);
    font-size: 12px;
    color: #4caf50;
    opacity: 0;
    transition: opacity 0.3s ease-in-out;
  }
  .copied-msg.visible { opacity: 1; }

  .pane { display: block; }
  .pane[hidden] { display: none; }

  .warn {
    color: #b00020;
    font-size: 12px;
    text-align: center;
  }

  @media (max-width: 700px) {
    .result-layout {
      grid-template-columns: 1fr;
      justify-items: center;
    }
    .label, .result-label {
      width: auto;
      text-align: center;
    }
    .row-layout { gap: 6px; }
    .result-row { width: 280px; }
    .segmented { grid-template-columns: 1fr 1fr; }
  }