body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #f4f4f4;
}

.container {
    background-color: #fff;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    text-align: center;
    width: 90%;
    max-width: 500px;
}

h1 {
    color: #333;
    margin-bottom: 20px;
}

.control-group {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.control-group label {
    font-weight: bold;
    flex-basis: 60%;
    text-align: left;
}

.control-group input[type="range"] {
    flex-basis: 30%;
}

.control-group #intensity-switch {
    flex-basis: 10%;
    width: auto;
}

.control-group span {
    font-weight: bold;
    flex-basis: 10%;
    text-align: right;
}

button {
    background-color: #007bff;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    margin: 5px;
}

button:hover {
    background-color: #0056b3;
}

button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
}

/* 強弱切り替えスイッチのスタイル調整 */
#intensity-switch {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    position: relative;
    width: 40px;
    height: 20px;
    background-color: #ccc;
    border-radius: 10px;
    outline: none;
    transition: .4s;
    cursor: pointer;
}

#intensity-switch:checked {
    background-color: #2196F3;
}

#intensity-switch::before {
    content: '';
    position: absolute;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background-color: white;
    top: 2px;
    left: 2px;
    transition: .4s;
}

#intensity-switch:checked::before {
    transform: translateX(20px);
}