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

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

.container {
    max-width: 700px;
    margin: 0 auto;
}

.header {
    text-align: center;
    color: white;
    margin-bottom: 30px;
    padding: 20px 0;
}

.header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
}

.header p {
    font-size: 1.1em;
    opacity: 0.9;
}

.main-content {
    background: white;
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    margin-bottom: 30px;
}

/* 입력 영역 */
.download-section {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.input-group {
    display: flex;
    flex-direction: column;
}

.url-input {
    padding: 15px;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    font-size: 1em;
    transition: border-color 0.3s;
}

.url-input:focus {
    outline: none;
    border-color: #667eea;
}

.options {
    display: flex;
    gap: 20px;
}

.radio-group {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    flex: 1;
}

.radio-group input[type="radio"] {
    cursor: pointer;
    width: 18px;
    height: 18px;
}

.radio-label {
    cursor: pointer;
    font-size: 1em;
}

/* 버튼 */
.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 600;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-primary:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.btn-secondary {
    background: #f0f0f0;
    color: #333;
}

.btn-secondary:hover {
    background: #e0e0e0;
}

/* 상태 섹션 */
.status-section,
.complete-section,
.error-section {
    margin-top: 20px;
    padding: 20px;
    border-radius: 8px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.status-section {
    background: #f5f5f5;
    border: 1px solid #e0e0e0;
}

.status-card {
    background: white;
    padding: 20px;
    border-radius: 8px;
    border: 2px solid #667eea;
}

.status-message {
    font-size: 1.1em;
    font-weight: 600;
    color: #333;
    margin-bottom: 15px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: #e0e0e0;
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    transition: width 0.3s;
}

.status-detail {
    text-align: right;
    font-size: 0.9em;
    color: #666;
}

.complete-section {
    background: #e8f5e9;
    border: 2px solid #4caf50;
}

.success-message {
    color: #2e7d32;
}

.success-message h3 {
    margin-bottom: 8px;
}

.error-section {
    background: #ffebee;
    border: 2px solid #f44336;
}

.error-message {
    color: #c62828;
}

.error-message h3 {
    margin-bottom: 8px;
}

/* 파일 목록 */
.files-section {
    background: white;
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.files-section h2 {
    margin-bottom: 20px;
    color: #333;
}

.files-list {
    margin-bottom: 20px;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px;
    border: 1px solid #e0e0e0;
    border-radius: 6px;
    margin-bottom: 8px;
    background: #f9f9f9;
}

.file-info {
    flex: 1;
}

.file-name {
    font-weight: 500;
    color: #333;
    word-break: break-all;
}

.file-size {
    font-size: 0.85em;
    color: #999;
    margin-top: 4px;
}

.loading {
    text-align: center;
    color: #999;
    padding: 20px;
}

.empty {
    text-align: center;
    color: #999;
    padding: 20px;
}

/* Hidden */
.hidden {
    display: none !important;
}

/* 반응형 */
@media (max-width: 600px) {
    .header h1 {
        font-size: 2em;
    }

    .main-content,
    .files-section {
        padding: 20px;
    }

    .options {
        flex-direction: column;
    }

    .url-input {
        padding: 12px;
    }
}