/* ================================================
   LifeHack Daily - Main Stylesheet
   애드센스 최적화 블로그 스타일
   ================================================ */

/* ================================================
   1. CSS Variables & Reset
   ================================================ */

/* Reading Progress Bar */
.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background-color: var(--gray-200);
    z-index: 9999;
}

.reading-progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--primary-light));
    width: 0%;
    transition: width 0.1s ease;
    box-shadow: 0 0 10px rgba(0, 180, 216, 0.5);
}

:root {
    /* Primary Colors */
    --primary-color: #00B4D8;
    --primary-dark: #0096C7;
    --primary-light: #90E0EF;
    
    /* Secondary Colors */
    --secondary-color: #2B2D42;
    --secondary-light: #8D99AE;
    
    /* Accent Colors */
    --accent-color: #EF476F;
    --accent-hover: #D63650;
    
    /* Neutral Colors */
    --white: #FFFFFF;
    --gray-100: #F8F9FA;
    --gray-200: #E9ECEF;
    --gray-300: #DEE2E6;
    --gray-400: #CED4DA;
    --gray-500: #ADB5BD;
    --gray-600: #6C757D;
    --gray-700: #495057;
    --gray-800: #343A40;
    --gray-900: #212529;
    --black: #000000;
    
    /* Typography */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.7;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    
    /* Layout */
    --container-width: 1200px;
    --content-width: 800px;
    --border-radius: 12px;
    --border-radius-sm: 8px;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html {
    font-size: var(--font-size-base);
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    line-height: var(--line-height-base);
    color: var(--gray-900);
    background-color: var(--gray-100);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color var(--transition-fast);
}

ul, ol {
    list-style: none;
}

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
    transition: all var(--transition-fast);
}

/* ================================================
   2. Layout Components
   ================================================ */

/* Container */
.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ================================================
   3. Header & Navigation
   ================================================ */
.site-header {
    background-color: var(--white);
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: box-shadow var(--transition-base);
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md) 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary-color);
}

.logo i {
    font-size: 1.8rem;
}

.logo-text {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-menu a {
    font-weight: 500;
    color: var(--gray-700);
    position: relative;
    padding: 0.5rem 0;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--primary-color);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: width var(--transition-base);
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

/* Dropdown */
.dropdown {
    position: relative;
}

.dropdown-toggle {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    background-color: var(--white);
    border-radius: var(--border-radius-sm);
    box-shadow: var(--shadow-lg);
    padding: var(--spacing-sm);
    min-width: 200px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all var(--transition-base);
}

.dropdown:hover .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-menu li {
    padding: 0;
}

.dropdown-menu a {
    display: block;
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    color: var(--gray-700);
}

.dropdown-menu a:hover {
    background-color: var(--gray-100);
    color: var(--primary-color);
}

/* Mobile Toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background-color: var(--gray-700);
    border-radius: 2px;
    transition: all var(--transition-base);
}

/* Search Icon */
.search-icon {
    font-size: 1.2rem;
    color: var(--gray-700);
    cursor: pointer;
    padding: 0.5rem;
}

.search-icon:hover {
    color: var(--primary-color);
}

/* Search Bar */
.search-bar {
    display: none;
    padding: var(--spacing-md) 0;
    border-top: 1px solid var(--gray-200);
    animation: slideDown var(--transition-base);
}

.search-bar.active {
    display: block;
}

.search-container {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

.search-container input {
    flex: 1;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--gray-300);
    border-radius: var(--border-radius-sm);
    font-size: 1rem;
    transition: border-color var(--transition-fast);
}

.search-container input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.search-btn,
.search-close {
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius-sm);
    font-weight: 600;
}

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

.search-btn:hover {
    background-color: var(--primary-dark);
}

.search-close {
    background-color: var(--gray-200);
    color: var(--gray-700);
}

.search-close:hover {
    background-color: var(--gray-300);
}

/* ================================================
   4. Hero Section
   ================================================ */
.hero-section {
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--primary-color) 100%);
    padding: var(--spacing-2xl) 0;
    text-align: center;
    color: var(--white);
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: var(--spacing-sm);
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    opacity: 0.95;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: var(--spacing-lg);
    opacity: 0.9;
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
}

/* ================================================
   5. Buttons
   ================================================ */
.btn {
    display: inline-block;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--border-radius-sm);
    font-weight: 600;
    font-size: 1rem;
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-base);
}

.btn-primary {
    background-color: var(--accent-color);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-outline {
    background-color: transparent;
    color: var(--white);
    border: 2px solid var(--white);
}

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

/* ================================================
   6. AdSense Areas
   ================================================ */
.ad-container {
    margin: var(--spacing-lg) 0;
}

.ad-placeholder {
    background-color: var(--gray-200);
    border: 2px dashed var(--gray-400);
    border-radius: var(--border-radius-sm);
    padding: var(--spacing-xl);
    text-align: center;
    min-height: 100px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.ad-label {
    color: var(--gray-500);
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 1px;
}

.ad-header .ad-placeholder {
    min-height: 90px;
}

.ad-sidebar .ad-placeholder {
    min-height: 250px;
}

.ad-content .ad-placeholder {
    min-height: 100px;
}

/* ================================================
   7. Main Content Layout
   ================================================ */
.main-content {
    padding: var(--spacing-xl) 0;
}

.content-wrapper {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: var(--spacing-xl);
}

.posts-column {
    min-width: 0;
}

/* ================================================
   8. Filter Section
   ================================================ */
.filter-section {
    background-color: var(--white);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    margin-bottom: var(--spacing-lg);
}

.filter-buttons {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.filter-btn {
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius-sm);
    background-color: var(--gray-100);
    color: var(--gray-700);
    font-weight: 500;
    font-size: 0.9rem;
}

.filter-btn:hover {
    background-color: var(--primary-light);
    color: var(--primary-dark);
}

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

/* ================================================
   9. Featured Post
   ================================================ */
.featured-post {
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    margin-bottom: var(--spacing-xl);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.featured-post:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.post-image {
    position: relative;
    overflow: hidden;
    height: 400px;
}

.post-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.featured-post:hover .post-image img {
    transform: scale(1.05);
}

.post-badge {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 1px;
}

.featured-badge {
    background-color: var(--accent-color);
    color: var(--white);
}

.post-content {
    padding: var(--spacing-lg);
}

.post-meta {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
    font-size: 0.875rem;
    color: var(--gray-600);
}

.post-meta span {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.post-category {
    color: var(--primary-color);
    font-weight: 600;
}

.post-title {
    font-size: 2rem;
    font-weight: 800;
    line-height: 1.3;
    margin-bottom: var(--spacing-md);
    color: var(--gray-900);
}

.post-title a {
    color: inherit;
    transition: color var(--transition-fast);
}

.post-title a:hover {
    color: var(--primary-color);
}

.post-excerpt {
    font-size: 1.05rem;
    line-height: 1.8;
    color: var(--gray-700);
    margin-bottom: var(--spacing-md);
}

.post-tags {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
}

.tag {
    padding: 0.4rem var(--spacing-sm);
    background-color: var(--gray-100);
    color: var(--gray-700);
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.tag:hover {
    background-color: var(--primary-light);
    color: var(--primary-dark);
}

.post-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--gray-200);
}

.read-more {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary-color);
    font-weight: 600;
}

.read-more:hover {
    gap: 0.7rem;
}

.post-stats {
    display: flex;
    gap: var(--spacing-md);
    color: var(--gray-600);
    font-size: 0.875rem;
}

.post-stats span {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

/* ================================================
   10. Post Cards Grid
   ================================================ */
.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.post-card {
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    transition: all var(--transition-base);
}

.post-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.post-card-image {
    height: 200px;
    overflow: hidden;
}

.post-card-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.post-card:hover .post-card-image img {
    transform: scale(1.1);
}

.post-card-content {
    padding: var(--spacing-md);
}

.post-card-title {
    font-size: 1.25rem;
    font-weight: 700;
    line-height: 1.4;
    margin-bottom: var(--spacing-sm);
}

.post-card-title a:hover {
    color: var(--primary-color);
}

.post-card-excerpt {
    font-size: 0.95rem;
    color: var(--gray-600);
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.read-more-small {
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    color: var(--primary-color);
    font-weight: 600;
    font-size: 0.9rem;
}

.read-more-small:hover {
    gap: 0.5rem;
}

/* ================================================
   11. Pagination
   ================================================ */
.pagination {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-xl);
}

.page-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-sm);
    background-color: var(--white);
    color: var(--gray-700);
    font-weight: 600;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-fast);
}

.page-link:hover:not(.disabled) {
    background-color: var(--primary-color);
    color: var(--white);
}

.page-link.active {
    background-color: var(--primary-color);
    color: var(--white);
}

.page-link.disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

/* ================================================
   12. Sidebar Widgets
   ================================================ */
.sidebar {
    position: sticky;
    top: 100px;
    height: fit-content;
}

.widget {
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.widget-title {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    color: var(--gray-900);
}

.widget-description {
    font-size: 0.95rem;
    color: var(--gray-600);
    margin-bottom: var(--spacing-md);
    line-height: 1.6;
}

/* Newsletter Widget */
.newsletter-form {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.newsletter-form input {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--gray-300);
    border-radius: var(--border-radius-sm);
    font-size: 1rem;
}

.newsletter-form input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.newsletter-note {
    font-size: 0.8rem;
    color: var(--gray-500);
    margin-top: var(--spacing-sm);
}

/* Popular Posts Widget */
.popular-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.popular-item {
    display: flex;
    gap: var(--spacing-md);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--gray-200);
}

.popular-item:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.popular-number {
    flex-shrink: 0;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--white);
    border-radius: 50%;
    font-weight: 700;
    font-size: 0.9rem;
}

.popular-content {
    flex: 1;
    min-width: 0;
}

.popular-content a {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--gray-800);
    line-height: 1.4;
    display: block;
    margin-bottom: 0.3rem;
}

.popular-content a:hover {
    color: var(--primary-color);
}

.popular-views {
    font-size: 0.8rem;
    color: var(--gray-500);
}

/* Tag Cloud Widget */
.tag-cloud {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.tag-item {
    padding: 0.5rem var(--spacing-md);
    background-color: var(--gray-100);
    color: var(--gray-700);
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.tag-item:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

/* Social Widget */
.social-links {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.social-link {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    color: var(--white);
    font-size: 1.1rem;
    transition: all var(--transition-base);
}

.social-link.facebook { background-color: #1877F2; }
.social-link.twitter { background-color: #1DA1F2; }
.social-link.instagram { background: linear-gradient(45deg, #F58529, #DD2A7B, #8134AF); }
.social-link.linkedin { background-color: #0A66C2; }
.social-link.youtube { background-color: #FF0000; }

.social-link:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}

/* ================================================
   13. Footer
   ================================================ */
.site-footer {
    background-color: var(--secondary-color);
    color: var(--white);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
    margin-top: var(--spacing-2xl);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-column h4 {
    margin-bottom: var(--spacing-md);
    font-size: 1.1rem;
    font-weight: 700;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.footer-description {
    color: var(--secondary-light);
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.footer-social {
    display: flex;
    gap: var(--spacing-sm);
}

.footer-social a {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    transition: all var(--transition-base);
}

.footer-social a:hover {
    background-color: var(--primary-color);
    transform: translateY(-3px);
}

.footer-links li {
    margin-bottom: var(--spacing-sm);
}

.footer-links a {
    color: var(--secondary-light);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--primary-color);
}

.footer-contact li {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    color: var(--secondary-light);
}

.footer-bottom {
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
    color: var(--secondary-light);
}

.footer-bottom p {
    margin-bottom: 0.5rem;
}

.footer-bottom i {
    color: var(--accent-color);
}

/* ================================================
   14. Scroll to Top Button
   ================================================ */
.scroll-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--white);
    border: none;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    box-shadow: 0 4px 20px rgba(0, 180, 216, 0.4);
    opacity: 0;
    visibility: hidden;
    transform: scale(0.8);
    transition: all var(--transition-base);
    cursor: pointer;
    z-index: 999;
}

.scroll-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: scale(1);
}

.scroll-to-top:hover {
    background: linear-gradient(135deg, var(--primary-dark), var(--primary-color));
    transform: translateY(-5px) scale(1.1);
    box-shadow: 0 6px 25px rgba(0, 180, 216, 0.6);
}

.scroll-to-top:active {
    transform: translateY(-3px) scale(1.05);
}

/* ================================================
   14.5 Image Gallery Grid
   ================================================ */
.image-gallery {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
    margin: var(--spacing-xl) 0;
}

.gallery-item {
    position: relative;
    overflow: hidden;
    border-radius: var(--border-radius);
    aspect-ratio: 4 / 3;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
}

.gallery-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.gallery-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.gallery-item:hover img {
    transform: scale(1.1);
}

.gallery-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.8), transparent);
    color: var(--white);
    padding: var(--spacing-md);
    font-size: 0.9rem;
    transform: translateY(100%);
    transition: transform var(--transition-base);
}

.gallery-item:hover .gallery-caption {
    transform: translateY(0);
}

/* Responsive Image Grid */
@media (max-width: 768px) {
    .image-gallery {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-sm);
    }
}

@media (max-width: 480px) {
    .image-gallery {
        grid-template-columns: 1fr;
    }
}

/* ================================================
   15. Article Page Styles
   ================================================ */
.breadcrumb {
    background-color: var(--gray-100);
    padding: var(--spacing-md) 0;
    font-size: 0.9rem;
}

.breadcrumb .container {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--gray-600);
}

.breadcrumb a {
    color: var(--primary-color);
}

.breadcrumb a:hover {
    text-decoration: underline;
}

.article-page {
    padding: var(--spacing-xl) 0;
}

.article-wrapper {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: var(--spacing-xl);
}

.article-content {
    background-color: var(--white);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xl);
}

.article-header {
    margin-bottom: var(--spacing-xl);
}

.article-meta {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-md);
    font-size: 0.875rem;
    color: var(--gray-600);
}

.article-category {
    color: var(--primary-color);
    font-weight: 600;
}

.article-title {
    font-size: 2.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--gray-900);
}

.article-subtitle {
    font-size: 1.2rem;
    color: var(--gray-600);
    line-height: 1.7;
    margin-bottom: var(--spacing-lg);
}

.article-featured-image {
    border-radius: var(--border-radius);
    overflow: hidden;
    margin-bottom: var(--spacing-lg);
}

.article-author-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
    border-top: 1px solid var(--gray-200);
    border-bottom: 1px solid var(--gray-200);
    margin-bottom: var(--spacing-md);
}

.author-avatar {
    font-size: 3rem;
    color: var(--primary-color);
}

.author-name {
    font-weight: 700;
    color: var(--gray-900);
    display: block;
    margin-bottom: 0.2rem;
}

.author-bio {
    font-size: 0.9rem;
    color: var(--gray-600);
}

.social-share {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.share-label {
    font-weight: 600;
    color: var(--gray-700);
}

.share-btn {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    color: var(--white);
    transition: all var(--transition-base);
}

.share-btn.facebook { background-color: #1877F2; }
.share-btn.twitter { background-color: #1DA1F2; }
.share-btn.linkedin { background-color: #0A66C2; }
.share-btn.kakao { background-color: #FEE500; color: #000; }
.share-btn.link { background-color: var(--gray-700); }

.share-btn:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
}

/* Article Body */
.article-body {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--gray-800);
}

.article-body h2 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-top: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
    color: var(--gray-900);
}

.article-body h3 {
    font-size: 1.4rem;
    font-weight: 700;
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    color: var(--gray-900);
}

.article-body h4 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-top: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    color: var(--gray-900);
}

.article-body p {
    margin-bottom: var(--spacing-md);
}

.article-body ul,
.article-body ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-lg);
}

.article-body li {
    list-style: disc;
    margin-bottom: var(--spacing-sm);
    line-height: 1.7;
}

.intro-paragraph {
    font-size: 1.2rem;
    font-weight: 500;
    color: var(--gray-700);
    line-height: 1.8;
    margin-bottom: var(--spacing-lg);
    padding: var(--spacing-lg);
    background-color: var(--gray-100);
    border-left: 4px solid var(--primary-color);
    border-radius: var(--border-radius-sm);
}

/* App Card */
.app-card {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background-color: var(--gray-100);
    border-radius: var(--border-radius-sm);
    margin: var(--spacing-md) 0;
}

.app-icon {
    font-size: 3rem;
}

.app-details h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 0.3rem;
}

.app-rating {
    color: #FFB800;
    font-size: 0.9rem;
}

.app-rating span {
    color: var(--gray-600);
    margin-left: 0.5rem;
}

/* Feature Box */
.feature-box {
    background-color: var(--primary-light);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    margin: var(--spacing-lg) 0;
}

.feature-box h4 {
    color: var(--primary-dark);
    margin-bottom: var(--spacing-md);
    font-size: 1.1rem;
}

.feature-box ul li {
    padding-left: 0.5rem;
}

/* Tip Box */
.tip-box {
    background-color: #FFF9E6;
    border-left: 4px solid #FFB800;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-sm);
    margin: var(--spacing-lg) 0;
}

.tip-box h4 {
    color: #CC9500;
    margin-bottom: var(--spacing-sm);
}

.tip-box p {
    margin-bottom: 0;
}

/* Conclusion List */
.conclusion-list {
    background-color: var(--gray-100);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    margin: var(--spacing-lg) 0;
}

.conclusion-list li {
    font-size: 1.05rem;
    padding: var(--spacing-sm) 0;
}

/* Article Tags */
.article-tags {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--gray-200);
}

/* Author Bio Card */
.author-bio-card {
    display: flex;
    gap: var(--spacing-lg);
    padding: var(--spacing-xl);
    background-color: var(--gray-100);
    border-radius: var(--border-radius);
    margin: var(--spacing-xl) 0;
}

.author-avatar-large {
    font-size: 5rem;
    color: var(--primary-color);
}

.author-bio-content h3 {
    margin-bottom: var(--spacing-sm);
    color: var(--gray-900);
}

.author-bio-content p {
    margin-bottom: var(--spacing-md);
    color: var(--gray-700);
}

.author-social {
    display: flex;
    gap: var(--spacing-sm);
}

.author-social a {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--white);
    border-radius: 50%;
    color: var(--gray-700);
    transition: all var(--transition-fast);
}

.author-social a:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

/* Comments Section */
.comments-section {
    margin-top: var(--spacing-xl);
    padding-top: var(--spacing-xl);
    border-top: 2px solid var(--gray-200);
}

.comments-title {
    font-size: 1.5rem;
    margin-bottom: var(--spacing-lg);
}

.comment-count {
    color: var(--primary-color);
}

.comment-form {
    margin-bottom: var(--spacing-xl);
}

.comment-form textarea {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--gray-300);
    border-radius: var(--border-radius-sm);
    font-family: inherit;
    font-size: 1rem;
    resize: vertical;
    margin-bottom: var(--spacing-md);
}

.comment-form textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.comments-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.comment-item {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    background-color: var(--gray-100);
    border-radius: var(--border-radius);
}

.comment-avatar {
    font-size: 2.5rem;
    color: var(--gray-400);
}

.comment-content {
    flex: 1;
}

.comment-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

.comment-author {
    font-weight: 700;
    color: var(--gray-900);
}

.comment-date {
    font-size: 0.875rem;
    color: var(--gray-500);
}

.comment-text {
    margin-bottom: var(--spacing-sm);
    line-height: 1.6;
}

.comment-actions {
    display: flex;
    gap: var(--spacing-md);
}

.comment-actions button {
    font-size: 0.875rem;
    color: var(--gray-600);
    transition: color var(--transition-fast);
}

.comment-actions button:hover {
    color: var(--primary-color);
}

.load-more-comments {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-sm) var(--spacing-lg);
    background-color: var(--gray-200);
    color: var(--gray-700);
    border-radius: var(--border-radius-sm);
    font-weight: 600;
    width: 100%;
}

.load-more-comments:hover {
    background-color: var(--gray-300);
}

/* Article Sidebar */
.article-sidebar .widget {
    position: sticky;
    top: 100px;
}

.widget-toc {
    background-color: var(--gray-100);
}

.toc-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toc-list li {
    list-style: none;
}

.toc-list a {
    display: block;
    padding: var(--spacing-sm);
    color: var(--gray-700);
    font-size: 0.95rem;
    border-radius: var(--border-radius-sm);
    border-left: 3px solid transparent;
    transition: all var(--transition-fast);
}

.toc-list a:hover {
    background-color: var(--white);
    color: var(--primary-color);
    padding-left: var(--spacing-md);
    border-left-color: var(--primary-light);
}

.toc-list a.active {
    background-color: var(--primary-light);
    color: var(--primary-color);
    font-weight: 600;
    border-left-color: var(--primary-color);
    box-shadow: var(--shadow-sm);
}

/* Related Posts */
.related-posts {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.related-post-item {
    display: flex;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    transition: background-color var(--transition-fast);
}

.related-post-item:hover {
    background-color: var(--gray-100);
}

.related-post-image {
    flex-shrink: 0;
    width: 80px;
    height: 60px;
    border-radius: var(--border-radius-sm);
    overflow: hidden;
}

.related-post-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.related-post-content h4 {
    font-size: 0.95rem;
    font-weight: 600;
    line-height: 1.4;
    margin-bottom: 0.3rem;
    color: var(--gray-800);
}

.related-post-item:hover h4 {
    color: var(--primary-color);
}

.related-post-date {
    font-size: 0.8rem;
    color: var(--gray-500);
}

/* ================================================
   16. Responsive Design
   ================================================ */

@media (max-width: 1024px) {
    .content-wrapper,
    .article-wrapper {
        grid-template-columns: 1fr;
    }
    
    .sidebar,
    .article-sidebar {
        position: static;
    }
}

@media (max-width: 768px) {
    /* Header */
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background-color: var(--white);
        flex-direction: column;
        padding: var(--spacing-lg);
        box-shadow: var(--shadow-xl);
        transition: left var(--transition-base);
        overflow-y: auto;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }
    
    .dropdown-menu {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        background-color: var(--gray-100);
        margin-top: var(--spacing-sm);
    }
    
    /* Hero */
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.2rem;
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-cta .btn {
        width: 100%;
    }
    
    /* Posts Grid */
    .posts-grid {
        grid-template-columns: 1fr;
    }
    
    /* Featured Post */
    .post-image {
        height: 250px;
    }
    
    .post-title {
        font-size: 1.5rem;
    }
    
    /* Article */
    .article-title {
        font-size: 1.8rem;
    }
    
    .article-content {
        padding: var(--spacing-md);
    }
    
    .article-body {
        font-size: 1rem;
    }
    
    .author-bio-card {
        flex-direction: column;
        text-align: center;
    }
    
    /* Footer */
    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .hero-section {
        padding: var(--spacing-lg) 0;
    }
    
    .filter-buttons {
        flex-direction: column;
    }
    
    .filter-btn {
        width: 100%;
    }
    
    .post-footer {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }
}

/* ================================================
   17. Animations
   ================================================ */
@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* ================================================
   18. Utility Classes
   ================================================ */
.hidden {
    display: none !important;
}

.visible {
    display: block !important;
}

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

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }