select {
      appearance: none;
      -webkit-appearance: none;
      -moz-appearance: none;
      background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg width='14' height='8' viewBox='0 0 14 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3e%3cpath d='M1 1L7 7L13 1' stroke='%23000' stroke-width='2'/%3e%3c/svg%3e");
      background-repeat: no-repeat;
      background-position: right 10px center; /* ขยับลูกศรมาทางซ้าย 10px จากขอบขวา */
      background-size: 14px 8px;
      padding-right: 40px; /* เว้นที่ขวาสำหรับลูกศร */
      cursor: pointer;
      width: 100%;
      padding: 12px 14px;
      font-size: 16px;
      border-radius: 8px;
      border: 1.8px solid #ccc;
      transition: border-color 0.25s ease;
      outline-offset: 2px;
      outline-color: transparent;
      font-weight: 500;
      color: #222;
      user-select: text;
    }
label {
    margin-top: 15px;
    margin-bottom: 5px;
    display: block;
    font-weight: 600;
}
input[type="number"] {
    padding: 10px 12px;
    margin-bottom: 10px;
    font-size: 1rem;
    width: 100%;
    border: 1px solid #ccc;
    border-radius: 8px;
    transition: border-color 0.2s;
}
input[type="number"]:focus {
    border: 1px solid #ccc;
    outline: none;
}
.section {
    margin-top: 20px;
    padding: 20px;
    background: #fff;
    border-left: 5px solid #74be43;
    border-radius: 8px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
}
.result {
    margin-top: 2rem;
    background: #ebebeb;
    padding: 1rem;
    border-radius: 8px;
}

.convert-btn {
    background-color: #fdc620;
    color: #43413d;
    cursor: pointer !important;
    padding: 10px 25px;
    letter-spacing: .1em;
    user-select: none;
    float: right;
}
.convert-btn:hover {
    background-color: #ffd863;
    color: #43413d;
}