/* 基本スタイル */
body, html {
    margin: 0;
    padding: 0;
    height: 100%;
    font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
    overflow: hidden;
    background-color: #f0f0f0;}
.container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    text-align: center;
    padding: 20px;
    box-sizing: border-box;}
.settings-box {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);}
h1 {
    margin-top: 0;
    color: #333;}
.input-group { margin-bottom: 20px; text-align: left; }
label { display: block; font-weight: bold; margin-bottom: 5px; }
input { 
    width: 100%; 
    padding: 10px; 
    font-size: 18px; 
    border: 1px solid #ccc; 
    border-radius: 5px;
    box-sizing: border-box;}
button {
    background-color: #007bff;
    color: white;
    border: none;
    padding: 15px 40px;
    font-size: 20px;
    font-weight: bold;
    border-radius: 30px;
    cursor: pointer;
    transition: background 0.3s;}
button:hover { background-color: #0056b3; }

/* 全画面色表示エリア */
#display-area {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 100;}

/* 履歴表示画面 */
#history-area {
    display: none;
    background: white;
    overflow-y: auto;
    max-height: 80vh;
    width: 90%;
    max-width: 400px;
    padding: 20px;
    border-radius: 15px;}
.history-item {
    padding: 10px;
    margin: 5px 0;
    border-radius: 5px;
    font-weight: bold;
    color: #fff;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.5);}

/* 各色の定義 */
.bg-red { background-color: #ff4b4b; }
.bg-blue { background-color: #4b7bff; }
.bg-yellow { background-color: #ffee00; }
.bg-green { background-color: #28a745; }