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

:root {
    --primary-color: #4f46e5;
    --secondary-color: #06b6d4;
    --accent-color: #f59e0b;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --bg-dark: #1f2937;
    
    --border-color: #e5e7eb;
    --border-light: #f3f4f6;
    
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 0.75rem;
    
    --sidebar-width: 280px;
    --header-height: 70px;
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* 헤더 스타일 */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow-md);
    height: var(--header-height);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.5rem;
    font-weight: 700;
    text-decoration: none;
    color: white;
}

.logo i {
    font-size: 2rem;
}

.nav {
    display: flex;
    gap: 0.5rem;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    text-decoration: none;
    color: rgba(255, 255, 255, 0.8);
    transition: all 0.2s ease;
    font-weight: 500;
}

.nav-link:hover,
.nav-link.active {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    backdrop-filter: blur(10px);
}

.search-box {
    position: relative;
    max-width: 300px;
    flex: 1;
}

.search-box input {
    width: 100%;
    padding: 0.75rem 1rem 0.75rem 3rem;
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
    transition: all 0.2s ease;
}

.search-box input::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.search-box input:focus {
    outline: none;
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
}

.search-box i {
    position: absolute;
    left: 1rem;
    top: 50%;
    transform: translateY(-50%);
    color: rgba(255, 255, 255, 0.6);
}

/* 메인 컨텐츠 스타일 */
.main {
    padding-top: 2rem;
    min-height: calc(100vh - var(--header-height));
}

.main-content {
    display: grid;
    grid-template-columns: var(--sidebar-width) 1fr;
    gap: 2rem;
    align-items: start;
}

/* 사이드바 스타일 */
.sidebar {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-light);
    position: sticky;
    top: calc(var(--header-height) + 2rem);
    max-height: calc(100vh - var(--header-height) - 4rem);
    overflow-y: auto;
}

.sidebar-section {
    margin-bottom: 2rem;
}

.sidebar-section:last-child {
    margin-bottom: 0;
}

.sidebar-section h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid var(--border-light);
}

.category-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.category-btn {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-secondary);
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.category-btn:hover {
    background: var(--bg-tertiary);
    border-color: var(--primary-color);
    transform: translateY(-1px);
}

.category-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

.filter-group {
    margin-bottom: 1rem;
}

.filter-group label {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.filter-group select {
    width: 100%;
    padding: 0.6rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.9rem;
    cursor: pointer;
    transition: border-color 0.2s ease;
}

.filter-group select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.bookmark-list {
    max-height: 200px;
    overflow-y: auto;
}

.bookmark-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.bookmark-item:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

/* 콘텐츠 영역 스타일 */
.content {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    padding: 2rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-light);
    min-height: 600px;
}

.page {
    display: none;
}

.page.active {
    display: block;
}

.page-header {
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
    border-bottom: 2px solid var(--border-light);
}

.page-header h1 {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.page-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
}

.view-toggle {
    display: flex;
    gap: 0.5rem;
}

.view-btn {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.view-btn:hover,
.view-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* 통계 카드 스타일 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 1.5rem;
    border-radius: var(--radius-xl);
    text-align: center;
    box-shadow: var(--shadow-md);
    transition: transform 0.2s ease;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.stat-card i {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    opacity: 0.8;
}

.stat-card h3 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-card p {
    font-size: 1rem;
    opacity: 0.9;
}

/* 강의 그리드 스타일 */
.lecture-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1.5rem;
}

.lecture-grid.list-view {
    grid-template-columns: 1fr;
}

.lecture-card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-light);
    overflow: hidden;
    transition: all 0.2s ease;
    cursor: pointer;
    box-shadow: var(--shadow-sm);
}

.lecture-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.lecture-thumbnail {
    position: relative;
    height: 180px;
    background: linear-gradient(45deg, var(--bg-tertiary), var(--border-light));
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.lecture-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.lecture-thumbnail .play-icon {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(0, 0, 0, 0.7);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    backdrop-filter: blur(10px);
    transition: all 0.2s ease;
}

.lecture-card:hover .play-icon {
    background: var(--primary-color);
    transform: translate(-50%, -50%) scale(1.1);
}

.lecture-duration {
    position: absolute;
    bottom: 0.5rem;
    right: 0.5rem;
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 500;
}

.lecture-content {
    padding: 1.5rem;
}

.lecture-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.lecture-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1rem;
    font-size: 0.85rem;
}

.lecture-instructor {
    color: var(--primary-color);
    font-weight: 500;
}

.lecture-difficulty {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    font-weight: 500;
}

.lecture-difficulty.초급 {
    background: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
}

.lecture-difficulty.중급 {
    background: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

.lecture-difficulty.고급 {
    background: rgba(239, 68, 68, 0.1);
    color: var(--error-color);
}

.lecture-description {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
    margin-bottom: 1rem;
}

.lecture-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: 1rem;
    border-top: 1px solid var(--border-light);
}

.lecture-stats {
    display: flex;
    gap: 1rem;
    font-size: 0.85rem;
    color: var(--text-light);
}

.lecture-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-icon {
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-icon:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.btn-icon.bookmarked {
    background: var(--warning-color);
    color: white;
    border-color: var(--warning-color);
}

/* 업로드 폼 스타일 */
.upload-form {
    max-width: 800px;
    margin: 0 auto;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.9rem;
    font-family: inherit;
    transition: border-color 0.2s ease;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.form-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    padding-top: 2rem;
    border-top: 1px solid var(--border-light);
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.2s ease;
    line-height: 1;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: #3730a3;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border-color: var(--border-color);
}

.btn-secondary:hover {
    background: var(--border-color);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-outline:hover {
    background: var(--primary-color);
    color: white;
}

/* 학습 진도 스타일 */
.progress-summary {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
    padding: 2rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: var(--radius-xl);
    color: white;
}

.progress-card h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    opacity: 0.9;
}

.progress-circle {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(white 0deg, rgba(255, 255, 255, 0.3) 0deg);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.progress-circle::before {
    content: '';
    width: 90px;
    height: 90px;
    border-radius: 50%;
    background: var(--primary-color);
    position: absolute;
}

.progress-text {
    font-size: 1.5rem;
    font-weight: 700;
    position: relative;
    z-index: 1;
}

.progress-stats {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    justify-content: center;
}

.progress-stat {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.progress-stat i {
    font-size: 1.5rem;
    opacity: 0.8;
}

.stat-number {
    font-size: 1.5rem;
    font-weight: 700;
    display: block;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.9;
}

.recent-lectures-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.recent-lecture-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    cursor: pointer;
    transition: all 0.2s ease;
}

.recent-lecture-item:hover {
    background: var(--bg-primary);
    border-color: var(--primary-color);
    transform: translateY(-1px);
    box-shadow: var(--shadow-sm);
}

.recent-lecture-thumbnail {
    width: 80px;
    height: 60px;
    border-radius: var(--radius-md);
    background: var(--bg-tertiary);
    flex-shrink: 0;
}

.recent-lecture-info {
    flex: 1;
}

.recent-lecture-title {
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.recent-lecture-meta {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.recent-lecture-progress {
    width: 100px;
    flex-shrink: 0;
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--bg-tertiary);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 0.25rem;
}

.progress-fill {
    height: 100%;
    background: var(--primary-color);
    border-radius: 3px;
    transition: width 0.3s ease;
}

.progress-text-small {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-align: right;
}

/* 모달 스타일 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    z-index: 2000;
    backdrop-filter: blur(5px);
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.modal-content {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    max-width: 1000px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 2rem;
    border-bottom: 1px solid var(--border-light);
}

.modal-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.modal-close {
    width: 40px;
    height: 40px;
    border: none;
    background: var(--bg-tertiary);
    border-radius: 50%;
    font-size: 1.5rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.modal-close:hover {
    background: var(--error-color);
    color: white;
}

.modal-body {
    padding: 2rem;
}

.video-container {
    position: relative;
    width: 100%;
    height: 400px;
    background: #000;
    border-radius: var(--radius-lg);
    overflow: hidden;
    margin-bottom: 2rem;
}

.video-container video {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.lecture-info {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.modal .lecture-meta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.modal .instructor,
.modal .difficulty,
.modal .duration {
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    font-weight: 500;
}

.modal .instructor {
    background: rgba(79, 70, 229, 0.1);
    color: var(--primary-color);
}

.modal .difficulty {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

.modal .duration {
    background: rgba(6, 182, 212, 0.1);
    color: var(--secondary-color);
}

.modal .lecture-description {
    color: var(--text-secondary);
    line-height: 1.6;
}

.modal .lecture-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
}

/* 페이지네이션 스타일 */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0.5rem;
    margin-top: 2rem;
    padding-top: 2rem;
    border-top: 1px solid var(--border-light);
}

.pagination button {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
    min-width: 40px;
}

.pagination button:hover:not(:disabled) {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.pagination button.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.pagination button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* 로딩 스타일 */
.loading {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.loading i {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

/* Toast 알림 스타일 */
.toast {
    position: fixed;
    top: 100px;
    right: 20px;
    z-index: 3000;
    transform: translateX(400px);
    transition: transform 0.3s ease;
}

.toast.show {
    transform: translateX(0);
}

.toast-content {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 1rem 1.5rem;
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-light);
    min-width: 300px;
}

.toast-icon {
    font-size: 1.25rem;
}

.toast.success .toast-icon {
    color: var(--success-color);
}

.toast.error .toast-icon {
    color: var(--error-color);
}

.toast.warning .toast-icon {
    color: var(--warning-color);
}

.toast.info .toast-icon {
    color: var(--secondary-color);
}

.toast-message {
    flex: 1;
    font-weight: 500;
    color: var(--text-primary);
}

/* 반응형 디자인 */
@media (max-width: 1024px) {
    .main-content {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .sidebar {
        position: static;
        max-height: none;
    }
    
    .lecture-grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    }
    
    .form-row {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 60px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 1rem;
        padding: 1rem 0;
    }
    
    .nav {
        order: 2;
        width: 100%;
        justify-content: center;
    }
    
    .nav-link {
        flex: 1;
        justify-content: center;
        font-size: 0.85rem;
    }
    
    .search-box {
        order: 1;
        max-width: 100%;
    }
    
    .main {
        padding-top: 1rem;
    }
    
    .content {
        padding: 1.5rem;
    }
    
    .page-header h1 {
        font-size: 1.75rem;
    }
    
    .stats-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 1rem;
    }
    
    .lecture-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .progress-summary {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .progress-stats {
        flex-direction: row;
        flex-wrap: wrap;
        justify-content: space-around;
    }
    
    .modal-content {
        margin: 1rem;
        max-height: calc(100vh - 2rem);
    }
    
    .modal-body {
        padding: 1rem;
    }
    
    .video-container {
        height: 250px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 0.75rem;
    }
    
    .content {
        padding: 1rem;
        border-radius: var(--radius-lg);
    }
    
    .sidebar {
        padding: 1rem;
    }
    
    .lecture-card {
        border-radius: var(--radius-lg);
    }
    
    .lecture-content {
        padding: 1rem;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
}

/* 스크롤바 스타일 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-light);
}

/* 포커스 스타일 */
button:focus,
input:focus,
select:focus,
textarea:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* 애니메이션 */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
    from { transform: translateX(-100%); }
    to { transform: translateX(0); }
}

.fade-in {
    animation: fadeIn 0.3s ease-out;
}

.slide-in {
    animation: slideIn 0.3s ease-out;
}

/* 유틸리티 클래스 */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-left { text-align: left; }

.mt-1 { margin-top: 0.25rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-3 { margin-top: 0.75rem; }
.mt-4 { margin-top: 1rem; }

.mb-1 { margin-bottom: 0.25rem; }
.mb-2 { margin-bottom: 0.5rem; }
.mb-3 { margin-bottom: 0.75rem; }
.mb-4 { margin-bottom: 1rem; }

.hidden { display: none !important; }
.visible { display: block !important; }