/* リセットとベース設定 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Hiragino Sans', 'Noto Sans JP', sans-serif;
    line-height: 1.6;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
    max-width: 500px;
    width: 100%;
    padding: 40px 30px;
    text-align: center;
    transition: transform 0.3s ease;
}

.container:hover {
    transform: translateY(-5px);
}

/* ヘッダー */
header h1 {
    font-size: 2.5em;
    color: #333;
    margin-bottom: 10px;
    font-weight: 600;
}

header p {
    color: #666;
    font-size: 1.1em;
    margin-bottom: 30px;
}

/* 時刻表示 */
.time-display {
    margin: 40px 0;
    padding: 30px;
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    border-radius: 15px;
    color: white;
    box-shadow: 0 10px 25px rgba(240, 147, 251, 0.3);
}

.current-time {
    font-size: 3.5em;
    font-weight: bold;
    margin-bottom: 10px;
    letter-spacing: 0.05em;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
    font-family: 'Courier New', monospace;
}

.current-date {
    font-size: 1.3em;
    opacity: 0.9;
    font-weight: 300;
}

/* コントロールボタン */
.controls {
    margin: 30px 0;
}

.btn {
    display: inline-block;
    padding: 15px 25px;
    margin: 10px;
    border: none;
    border-radius: 50px;
    font-size: 1.1em;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    min-width: 200px;
}

.btn.primary {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    color: white;
    box-shadow: 0 5px 15px rgba(79, 172, 254, 0.4);
}

.btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(79, 172, 254, 0.5);
}

.btn.secondary {
    background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    color: white;
    box-shadow: 0 5px 15px rgba(250, 112, 154, 0.4);
}

.btn.secondary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(250, 112, 154, 0.5);
}

.btn:active {
    transform: scale(0.98);
}

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

/* 設定 */
.settings {
    margin-top: 25px;
    padding-top: 20px;
    border-top: 1px solid #eee;
}

.settings label {
    display: block;
    margin: 15px 0;
    color: #555;
    font-size: 1em;
    cursor: pointer;
    transition: color 0.3s ease;
}

.settings label:hover {
    color: #333;
}

.settings input[type="checkbox"] {
    margin-right: 10px;
    transform: scale(1.2);
    cursor: pointer;
}

/* 時刻同期ステータス */
.time-source {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #eee;
    color: #777;
    font-size: 0.9em;
}

.sync-status {
    font-size: 1.5em;
    margin-top: 5px;
}

.sync-status.synced {
    color: #4CAF50;
}

.sync-status.error {
    color: #f44336;
}

/* フッター */
footer {
    margin-top: 30px;
    color: #888;
    font-size: 0.9em;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .container {
        padding: 30px 20px;
        margin: 10px;
    }
    
    header h1 {
        font-size: 2em;
    }
    
    .current-time {
        font-size: 2.5em;
    }
    
    .current-date {
        font-size: 1.1em;
    }
    
    .btn {
        min-width: 160px;
        padding: 12px 20px;
        font-size: 1em;
        margin: 8px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 20px 15px;
    }
    
    .current-time {
        font-size: 2em;
    }
    
    .btn {
        min-width: 140px;
        font-size: 0.9em;
    }
    
    .time-display {
        padding: 20px;
    }
}

/* アニメーション */
@keyframes pulse {
    0% { opacity: 1; }
    50% { opacity: 0.5; }
    100% { opacity: 1; }
}

.syncing {
    animation: pulse 1.5s infinite;
}