/**
 * Learning Platform - 다크 테마 CSS
 * 모바일 퍼스트, 반응형 디자인
 */

/* ========== CSS 변수 (다크 테마) ========== */
:root {
    /* 색상 팔레트 */
    --bg-primary: #0a0e27;
    --bg-secondary: #151932;
    --bg-tertiary: #1e2139;
    --bg-card: #252a41;
    --bg-card-hover: #2d3348;

    /* 텍스트 색상 */
    --text-primary: #e8eaf0;
    --text-secondary: #a8abb8;
    --text-muted: #6b6e7d;

    /* 액센트 색상 */
    --accent-primary: #00f0ff; /* 사이버 블루 */
    --accent-secondary: #7c3aed; /* 퍼플 */
    --accent-success: #10b981;
    --accent-warning: #f59e0b;
    --accent-error: #ef4444;

    /* 그라디언트 */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-accent: linear-gradient(135deg, #00f0ff 0%, #7c3aed 100%);

    /* 간격 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;

    /* 반경 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;

    /* 그림자 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.6);

    /* 전환 */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;

    /* 타이포그래피 */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'Fira Code', 'Consolas', 'Monaco', 'Courier New', monospace;
}

/* ========== 리셋 및 기본 스타일 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
}

/* ========== 그리드 배경 효과 ========== */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        linear-gradient(rgba(0, 240, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 240, 255, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    pointer-events: none;
    z-index: 0;
    animation: grid-move 60s linear infinite;
}

@keyframes grid-move {
    0% { transform: translate(0, 0); }
    100% { transform: translate(50px, 50px); }
}

/* ========== 레이아웃 컨테이너 ========== */
.lp-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-md);
    position: relative;
    z-index: 1;
}

.lp-container-fluid {
    width: 100%;
    padding: var(--spacing-md);
}

/* ========== 헤더 ========== */
.lp-header {
    background: var(--bg-secondary);
    border-bottom: 1px solid rgba(0, 240, 255, 0.1);
    padding: var(--spacing-lg) 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
}

.lp-header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.lp-logo {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent-primary);
    text-shadow: 0 0 10px rgba(0, 240, 255, 0.5);
    text-decoration: none;
    letter-spacing: 1px;
}

.lp-nav {
    display: flex;
    gap: var(--spacing-lg);
    align-items: center;
}

.lp-nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-base);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
}

.lp-nav-link:hover {
    color: var(--accent-primary);
    background: rgba(0, 240, 255, 0.1);
}

.lp-nav-link.active {
    color: var(--accent-primary);
    background: rgba(0, 240, 255, 0.15);
}

/* ========== 사이드바 + 메인 레이아웃 ========== */
.lp-main-layout {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: var(--spacing-xl);
    max-width: 1400px;
    margin: var(--spacing-xl) auto;
    padding: 0 var(--spacing-md);
}

/* ========== 사이드바 ========== */
.lp-sidebar {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    height: fit-content;
    position: sticky;
    top: 100px;
}

.lp-sidebar-section {
    margin-bottom: var(--spacing-xl);
}

.lp-sidebar-title {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: var(--spacing-md);
}

.lp-category-list {
    list-style: none;
}

.lp-category-item {
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: var(--spacing-xs);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-base);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.lp-category-item:hover {
    background: var(--bg-card);
    transform: translateX(4px);
}

.lp-category-item.active {
    background: rgba(0, 240, 255, 0.15);
    border-left: 3px solid var(--accent-primary);
}

.lp-category-count {
    font-size: 0.75rem;
    color: var(--text-muted);
    background: var(--bg-tertiary);
    padding: 2px 8px;
    border-radius: 10px;
}

/* ========== 프로그레스 바 ========== */
.lp-progress-section {
    background: var(--bg-card);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.lp-progress-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.lp-stat {
    text-align: center;
}

.lp-stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent-primary);
}

.lp-stat-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
}

.lp-progress-bar {
    width: 100%;
    height: 8px;
    background: var(--bg-tertiary);
    border-radius: 10px;
    overflow: hidden;
    position: relative;
}

.lp-progress-fill {
    height: 100%;
    background: var(--gradient-accent);
    border-radius: 10px;
    transition: width 0.6s ease;
    position: relative;
    overflow: hidden;
}

.lp-progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    animation: progress-shine 2s infinite;
}

@keyframes progress-shine {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

/* ========== 카드 컴포넌트 ========== */
.lp-card {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    border: 1px solid transparent;
}

.lp-card:hover {
    background: var(--bg-card-hover);
    box-shadow: var(--shadow-lg);
    border-color: rgba(0, 240, 255, 0.2);
    transform: translateY(-2px);
}

.lp-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
}

.lp-card-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.lp-badge {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.lp-badge-beginner {
    background: rgba(16, 185, 129, 0.2);
    color: var(--accent-success);
}

.lp-badge-intermediate {
    background: rgba(245, 158, 11, 0.2);
    color: var(--accent-warning);
}

.lp-badge-advanced {
    background: rgba(239, 68, 68, 0.2);
    color: var(--accent-error);
}

/* ========== 버튼 ========== */
.lp-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.9375rem;
    cursor: pointer;
    transition: all var(--transition-base);
    border: none;
    text-decoration: none;
    white-space: nowrap;
}

.lp-btn-primary {
    background: var(--gradient-accent);
    color: white;
    box-shadow: 0 0 20px rgba(0, 240, 255, 0.3);
}

.lp-btn-primary:hover {
    box-shadow: 0 0 30px rgba(0, 240, 255, 0.5);
    transform: translateY(-2px);
}

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

.lp-btn-secondary:hover {
    background: var(--bg-card);
}

.lp-btn-success {
    background: var(--accent-success);
    color: white;
}

.lp-btn-success:hover {
    filter: brightness(1.1);
}

.lp-btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
}

.lp-btn-icon:hover {
    background: var(--bg-card);
    color: var(--accent-primary);
}

/* ========== 퀴즈 목록 ========== */
.lp-quiz-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--spacing-lg);
}

.lp-quiz-card {
    position: relative;
    overflow: hidden;
}

.lp-quiz-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--gradient-accent);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.lp-quiz-card:hover::before {
    opacity: 1;
}

.lp-quiz-meta {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
    flex-wrap: wrap;
}

.lp-quiz-stat {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: 0.875rem;
    color: var(--text-muted);
}

/* ========== 코드 에디터 영역 ========== */
.lp-editor-container {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    overflow: hidden;
    margin: var(--spacing-lg) 0;
}

.lp-editor-header {
    background: var(--bg-tertiary);
    padding: var(--spacing-sm) var(--spacing-md);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(0, 240, 255, 0.1);
}

.lp-editor-tabs {
    display: flex;
    gap: var(--spacing-sm);
}

.lp-editor-tab {
    padding: var(--spacing-xs) var(--spacing-md);
    background: transparent;
    color: var(--text-secondary);
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.lp-editor-tab.active {
    background: var(--bg-card);
    color: var(--accent-primary);
}

.lp-editor-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.CodeMirror {
    height: 400px;
    font-family: var(--font-mono);
    font-size: 14px;
}

/* ========== 출력 콘솔 ========== */
.lp-console {
    background: #1a1d2e;
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    margin-top: var(--spacing-lg);
    font-family: var(--font-mono);
    font-size: 0.875rem;
}

.lp-console-header {
    color: var(--text-muted);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.lp-console-output {
    color: var(--text-primary);
    white-space: pre-wrap;
    word-break: break-all;
}

.lp-console-error {
    color: var(--accent-error);
}

.lp-console-success {
    color: var(--accent-success);
}

/* ========== 모달 ========== */
.lp-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-base);
}

.lp-modal.active {
    opacity: 1;
    pointer-events: all;
}

.lp-modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    max-width: 600px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    transform: scale(0.9);
    transition: transform var(--transition-base);
}

.lp-modal.active .lp-modal-content {
    transform: scale(1);
}

/* ========== 로딩 스피너 ========== */
.lp-spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(0, 240, 255, 0.3);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* ========== 터치 제스처 피드백 ========== */
.lp-touch-feedback {
    position: relative;
    overflow: hidden;
}

.lp-touch-feedback::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(0, 240, 255, 0.3);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.lp-touch-feedback:active::after {
    width: 200px;
    height: 200px;
}

/* ========== 반응형 디자인 ========== */

/* 태블릿 (768px 이하) */
@media (max-width: 768px) {
    .lp-main-layout {
        grid-template-columns: 1fr;
    }

    .lp-sidebar {
        position: static;
    }

    .lp-quiz-grid {
        grid-template-columns: 1fr;
    }

    .lp-nav {
        gap: var(--spacing-sm);
    }

    .CodeMirror {
        height: 300px;
    }
}

/* 모바일 (480px 이하) */
@media (max-width: 480px) {
    html {
        font-size: 14px;
    }

    .lp-header-content {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .lp-progress-stats {
        grid-template-columns: 1fr;
    }

    .lp-editor-header {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
}

/* 초소형 모바일 (320px) */
@media (max-width: 320px) {
    :root {
        --spacing-md: 0.75rem;
        --spacing-lg: 1rem;
    }

    .lp-container {
        padding: var(--spacing-sm);
    }
}

/* ========== 애니메이션 ========== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.lp-fade-in {
    animation: fadeIn 0.4s ease-out;
}

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

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

/* ========== 유틸리티 클래스 ========== */
.lp-text-center { text-align: center; }
.lp-text-right { text-align: right; }
.lp-mb-0 { margin-bottom: 0; }
.lp-mb-1 { margin-bottom: var(--spacing-sm); }
.lp-mb-2 { margin-bottom: var(--spacing-md); }
.lp-mb-3 { margin-bottom: var(--spacing-lg); }
.lp-mt-0 { margin-top: 0; }
.lp-mt-1 { margin-top: var(--spacing-sm); }
.lp-mt-2 { margin-top: var(--spacing-md); }
.lp-mt-3 { margin-top: var(--spacing-lg); }
.lp-hidden { display: none; }
.lp-flex { display: flex; }
.lp-items-center { align-items: center; }
.lp-justify-between { justify-content: space-between; }
.lp-gap-1 { gap: var(--spacing-sm); }
.lp-gap-2 { gap: var(--spacing-md); }
.lp-gap-3 { gap: var(--spacing-lg); }

/* ========== 스크롤바 스타일링 ========== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

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

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-primary);
}