/* 基本スタイル */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    color: #2c3e50;
    margin-bottom: 10px;
    font-size: 2.5rem;
}

header p {
    color: #7f8c8d;
    font-size: 1.1rem;
}

/* アップロードセクション */
.upload-section {
    margin-bottom: 30px;
}

.upload-area {
    text-align: center;
    padding: 40px;
    border: 2px dashed #bdc3c7;
    border-radius: 10px;
    background-color: white;
    transition: border-color 0.3s ease;
}

.upload-area:hover {
    border-color: #3498db;
}

.upload-btn {
    background-color: #3498db;
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 1.1rem;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.upload-btn:hover {
    background-color: #2980b9;
}

.upload-hint {
    margin-top: 10px;
    color: #7f8c8d;
    font-size: 0.9rem;
}

/* コントロールセクション */
.controls-section {
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    margin-bottom: 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.position-controls h3 {
    margin-bottom: 15px;
    color: #2c3e50;
}

.watermark-status {
    margin-bottom: 15px;
    padding: 8px 12px;
    background-color: #f8f9fa;
    border-radius: 4px;
    border-left: 4px solid #3498db;
}

.watermark-status.loaded {
    background-color: #d4edda;
    border-left-color: #28a745;
    color: #155724;
}

.watermark-status.error {
    background-color: #f8d7da;
    border-left-color: #dc3545;
    color: #721c24;
}

.position-buttons {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.position-btn {
    background-color: #ecf0f1;
    border: 2px solid #bdc3c7;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.position-btn:hover {
    background-color: #d5dbdb;
}

.position-btn.active {
    background-color: #3498db;
    color: white;
    border-color: #2980b9;
}

/* プレビューセクション */
.preview-section {
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    margin-bottom: 30px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.preview-container h3 {
    margin-bottom: 20px;
    color: #2c3e50;
}

#previewCanvas {
    max-width: 100%;
    height: auto;
    border: 1px solid #bdc3c7;
    border-radius: 5px;
    display: block;
    margin: 0 auto;
}

/* ダウンロードセクション */
.download-section {
    text-align: center;
    margin-bottom: 30px;
}

.download-btn {
    background-color: #27ae60;
    color: white;
    border: none;
    padding: 15px 30px;
    font-size: 1.1rem;
    border-radius: 5px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.download-btn:hover {
    background-color: #229954;
}

/* エラーセクション */
.error-section {
    background-color: #e74c3c;
    color: white;
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 20px;
}

.error-message {
    text-align: center;
    font-weight: bold;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    header h1 {
        font-size: 2rem;
    }
    
    .position-buttons {
        justify-content: center;
    }
    
    .upload-area {
        padding: 20px;
    }
}