* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
}

h1 {
    text-align: center;
    color: #333;
    margin-bottom: 8px;
}

.subtitle {
    text-align: center;
    color: #666;
    margin-bottom: 30px;
}

/* 設定區 */
.settings {
    display: flex;
    gap: 20px;
    align-items: center;
    justify-content: center;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.settings label {
    color: #555;
    font-weight: 500;
}

.settings input,
.settings select {
    padding: 10px 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s;
}

.settings input:focus,
.settings select:focus {
    outline: none;
    border-color: #667eea;
}

.settings input[type="number"] {
    width: 100px;
}

/* 上傳區 */
.upload-area {
    border: 3px dashed #ccc;
    border-radius: 16px;
    padding: 60px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
    background: #fafafa;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: #667eea;
    background: #f0f0ff;
}

.upload-icon {
    font-size: 48px;
    margin-bottom: 15px;
}

.upload-area p {
    color: #555;
    font-size: 18px;
}

.upload-area .hint {
    color: #999;
    font-size: 14px;
    margin-top: 8px;
}

/* 結果區 */
.results {
    margin-top: 30px;
}

.result-item {
    background: #f8f9fa;
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 20px;
}

.result-item img {
    width: 80px;
    height: 80px;
    object-fit: cover;
    border-radius: 8px;
}

.result-info {
    flex: 1;
}

.result-info h3 {
    color: #333;
    margin-bottom: 8px;
    word-break: break-all;
}

.result-info .size-info {
    color: #666;
    font-size: 14px;
}

.result-info .size-info span {
    color: #28a745;
    font-weight: bold;
}

.result-info .reduction {
    color: #667eea;
    font-weight: bold;
}

.result-info .unchanged {
    color: #ff9800;
    font-weight: bold;
}

.download-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 16px;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.download-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

/* 處理中狀態 */
.processing {
    text-align: center;
    padding: 20px;
    color: #666;
}

.processing::after {
    content: '';
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid #667eea;
    border-top-color: transparent;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-left: 10px;
    vertical-align: middle;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* 錯誤訊息 */
.error {
    background: #ffe6e6;
    color: #d32f2f;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 15px;
}

/* RWD */
@media (max-width: 600px) {
    .container {
        padding: 20px;
    }

    .settings {
        flex-direction: column;
        gap: 15px;
    }

    .result-item {
        flex-direction: column;
        text-align: center;
    }
}