/* ===== BLOG-STYLE.CSS - DESIGN HOÀN CHỈNH ===== */

/* CSS Variables */
:root {
    --color-primary: #1E3A8A;
    --color-secondary: #14B8A6;
    --color-text: #0F172A;
    --color-muted: #64748B;
    --color-light: #F8FAFC;
    --color-border: #E2E8F0;
    --shadow-light: 0 4px 12px rgba(0, 0, 0, 0.06);
    --shadow-medium: 0 8px 24px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 12px 30px rgba(0, 0, 0, 0.15);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--color-text);
    background-color: #FFFFFF;
}

a {
    color: var(--color-primary);
    text-decoration: none;
    transition: all 0.3s ease;
}

a:hover, a:focus {
    color: var(--color-secondary);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header Styles */
.header {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    padding: 1rem 0;
    box-shadow: var(--shadow-medium);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand .logo {
    color: white;
    font-weight: 700;
    font-size: 1.5rem;
    text-decoration: none;
    transition: all 0.3s ease;
}

.nav-brand .logo:hover {
    color: #E0F2FE;
    transform: scale(1.05);
}

.nav-menu {
    list-style: none;
    display: flex;
    gap: 2rem;
    margin: 0;
    padding: 0;
}

.nav-link {
    color: white;
    font-weight: 600;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    position: relative;
}

.nav-link:hover, .nav-link.active {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    transform: translateY(-2px);
}

/* Blog Header */
.blog-header {
    text-align: center;
    margin-bottom: 4rem;
    padding: 3rem 0;
    background: linear-gradient(135deg, var(--color-light) 0%, #E0F2FE 100%);
    border-radius: 20px;
    margin-top: 2rem;
}

.blog-header h1 {
    font-size: 3rem;
    color: var(--color-primary);
    font-weight: 800;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.blog-description {
    font-size: 1.3rem;
    color: var(--color-muted);
    max-width: 700px;
    margin: 0 auto;
    line-height: 1.7;
}

/* Category Filters */
.category-filters {
    margin-bottom: 4rem;
    text-align: center;
}

.filter-list {
    list-style: none;
    display: inline-flex;
    gap: 1rem;
    padding: 1rem;
    background: white;
    border-radius: 50px;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--color-border);
    flex-wrap: wrap;
    justify-content: center;
    margin: 0;
}

.filter-link {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    font-size: 0.95rem;
    background: transparent;
    color: var(--color-muted);
    border-radius: 25px;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    white-space: nowrap;
    position: relative;
    overflow: hidden;
}

.filter-link::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.4), transparent);
    transition: left 0.5s;
}

.filter-link:hover::before {
    left: 100%;
}

.filter-link:hover {
    background: var(--color-primary);
    color: white;
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(30, 58, 138, 0.3);
}

.filter-link.active {
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: white;
    box-shadow: 0 4px 15px rgba(30, 58, 138, 0.4);
    transform: translateY(-2px);
}

/* Posts Section */
.posts-section {
    margin: 2rem 0 6rem 0;
}

.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
    gap: 2.5rem;
    padding: 1rem 0;
}

/* Post Cards */
.post-card {
    background: white;
    border-radius: 20px;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--color-border);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.post-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.post-card:hover::before {
    transform: scaleX(1);
}

.post-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-heavy);
    border-color: var(--color-secondary);
}

.post-card img {
    width: 100%;
    height: 240px;
    object-fit: cover;
    transition: all 0.4s ease;
}

.post-card:hover img {
    transform: scale(1.08);
}

.post-card-content {
    padding: 2rem;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.post-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.post-category {
    background: var(--color-primary);
    color: white;
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 700;
    position: relative;
    overflow: hidden;
}

.post-category::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
    transition: left 0.6s;
}

.post-category:hover::before {
    left: 100%;
}

.category-exercise {
    background: linear-gradient(135deg, #059669, #10B981);
}

.category-science {
    background: linear-gradient(135deg, #6B21A8, #8B5CF6);
}

.category-astrology {
    background: linear-gradient(135deg, #DC2626, #EF4444);
}

.post-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: var(--color-text);
    font-weight: 700;
    line-height: 1.4;
    transition: color 0.3s ease;
}

.post-card h3 a {
    color: inherit;
    text-decoration: none;
    transition: all 0.3s ease;
    position: relative;
}

.post-card h3 a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transition: width 0.3s ease;
}

.post-card h3 a:hover::after {
    width: 100%;
}

.post-card h3 a:hover {
    color: var(--color-secondary);
}

.post-card p {
    flex-grow: 1;
    font-size: 1.05rem;
    color: var(--color-muted);
    line-height: 1.7;
    margin-bottom: 2rem;
}

.post-stats {
    display: flex;
    gap: 1.5rem;
    font-size: 0.9rem;
    color: var(--color-muted);
    margin-bottom: 1.5rem;
    padding: 1rem 0;
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.post-stats span {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-weight: 500;
}

.read-more {
    color: var(--color-primary);
    font-weight: 700;
    text-transform: uppercase;
    font-size: 0.9rem;
    letter-spacing: 1px;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    margin-top: auto;
    transition: all 0.3s ease;
    position: relative;
    padding: 0.5rem 0;
}

.read-more::after {
    content: '→';
    font-size: 1.2rem;
    transition: all 0.3s ease;
}

.read-more:hover {
    color: var(--color-secondary);
    transform: translateX(5px);
}

.read-more:hover::after {
    transform: translateX(5px);
}

/* Breadcrumb */
.breadcrumb {
    margin: 2rem 0;
    padding: 1rem 1.5rem;
    background: white;
    border-radius: 15px;
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-light);
}

.breadcrumb-list {
    list-style: none;
    display: flex;
    gap: 0.5rem;
    margin: 0;
    font-size: 0.95rem;
    color: var(--color-muted);
    align-items: center;
}

.breadcrumb-list li:not(:last-child)::after {
    content: '›';
    margin-left: 0.5rem;
    color: var(--color-border);
    font-weight: 700;
    font-size: 1.2rem;
}

.breadcrumb-list a {
    color: var(--color-muted);
    text-decoration: none;
    padding: 0.3rem 0.6rem;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.breadcrumb-list a:hover {
    color: var(--color-primary);
    background: rgba(30, 58, 138, 0.1);
}

.breadcrumb-list [aria-current="page"] {
    color: var(--color-primary);
    font-weight: 700;
}

/* Footer */
.footer {
    background: linear-gradient(135deg, var(--color-text) 0%, #374151 100%);
    color: white;
    padding: 3rem 0;
    text-align: center;
    margin-top: 4rem;
}

.footer p {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Responsive Design */
@media (max-width: 768px) {
    .blog-header {
        padding: 2rem 1rem;
        margin-top: 1rem;
    }
    
    .blog-header h1 {
        font-size: 2.2rem;
    }
    
    .blog-description {
        font-size: 1.1rem;
    }
    
    .posts-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .filter-list {
        flex-direction: column;
        gap: 0.5rem;
        padding: 1.5rem;
        border-radius: 20px;
    }
    
    .filter-link {
        width: 100%;
        text-align: center;
        padding: 1rem 2rem;
    }
    
    .nav-menu {
        gap: 1rem;
    }
    
    .post-card-content {
        padding: 1.5rem;
    }
}

@media (max-width: 480px) {
    .blog-header h1 {
        font-size: 1.8rem;
    }
    
    .blog-description {
        font-size: 1rem;
    }
    
    .post-card-content {
        padding: 1rem;
    }
    
    .breadcrumb {
        padding: 0.75rem 1rem;
    }
    
    .nav-menu {
        flex-wrap: wrap;
        gap: 0.5rem;
        justify-content: center;
    }
    
    .nav-link {
        padding: 0.4rem 0.8rem;
        font-size: 0.9rem;
    }
    
    .posts-grid {
        gap: 1.5rem;
    }
}

/* Animation keyframes */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.post-card {
    animation: fadeInUp 0.6s ease forwards;
}

.post-card:nth-child(1) { animation-delay: 0.1s; }
.post-card:nth-child(2) { animation-delay: 0.2s; }
.post-card:nth-child(3) { animation-delay: 0.3s; }
.post-card:nth-child(4) { animation-delay: 0.4s; }
.post-card:nth-child(5) { animation-delay: 0.5s; }
.post-card:nth-child(6) { animation-delay: 0.6s; }

/* Smooth scroll */
html {
    scroll-behavior: smooth;
}

/* Focus styles for accessibility */
.nav-link:focus,
.filter-link:focus,
.read-more:focus {
    outline: 2px solid var(--color-secondary);
    outline-offset: 2px;
}

/* ===== THUMBNAIL STYLING ===== */

/* Post card với thumbnail */
.post-card {
    background: white;
    border-radius: 20px;
    box-shadow: var(--shadow-light);
    border: 1px solid var(--color-border);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.post-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.post-card:hover::before {
    transform: scaleX(1);
}

.post-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-heavy);
    border-color: var(--color-secondary);
}

/* Thumbnail image */
.post-thumbnail {
    width: 100%;
    height: 240px;
    object-fit: cover;
    transition: transform 0.4s ease;
    border-radius: 0;
}

.post-card:hover .post-thumbnail {
    transform: scale(1.08);
}

/* Placeholder thumbnail nếu không có ảnh */
.post-thumbnail-placeholder {
    width: 100%;
    height: 240px;
    background: linear-gradient(135deg, #E2E8F0 0%, #CBD5E1 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-muted);
    font-size: 4rem;
    transition: all 0.4s ease;
    position: relative;
}

.post-card:hover .post-thumbnail-placeholder {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-secondary) 100%);
    color: white;
    transform: scale(1.02);
}

/* Category-specific placeholder colors */
.placeholder-exercise {
    background: linear-gradient(135deg, #ECFDF5 0%, #D1FAE5 100%);
    color: #059669;
}

.placeholder-science {
    background: linear-gradient(135deg, #F3E8FF 0%, #E9D5FF 100%);
    color: #7C3AED;
}

.placeholder-astrology {
    background: linear-gradient(135deg, #FEF2F2 0%, #FECACA 100%);
    color: #DC2626;
}

.post-card:hover .placeholder-exercise {
    background: linear-gradient(135deg, #059669 0%, #10B981 100%);
    color: white;
}

.post-card:hover .placeholder-science {
    background: linear-gradient(135deg, #7C3AED 0%, #8B5CF6 100%);
    color: white;
}

.post-card:hover .placeholder-astrology {
    background: linear-gradient(135deg, #DC2626 0%, #EF4444 100%);
    color: white;
}

/* Responsive thumbnail */
@media (max-width: 768px) {
    .post-thumbnail,
    .post-thumbnail-placeholder {
        height: 200px;
    }
    
    .post-thumbnail-placeholder {
        font-size: 3rem;
    }
}

@media (max-width: 480px) {
    .post-thumbnail,
    .post-thumbnail-placeholder {
        height: 180px;
    }
    
    .post-thumbnail-placeholder {
        font-size: 2.5rem;
    }
}

/* ===== THÊM CSS CHO ẢNH VÀ VIDEO ===== */
.post-image {
    margin: 2rem 0;
    text-align: center;
}

.post-image img {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

.post-image img:hover {
    transform: scale(1.02);
}

.post-image figcaption {
    margin-top: 0.5rem;
    font-size: 0.9rem;
    color: var(--color-muted);
    font-style: italic;
}

.post-video {
    margin: 2rem 0;
    text-align: center;
}

.post-video video {
    max-width: 100%;
    height: auto;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.video-caption {
    margin-top: 0.5rem;
    font-size: 0.9rem;
    color: var(--color-muted);
    font-style: italic;
}

@media (max-width: 768px) {
    .post-image img,
    .post-video video {
        border-radius: 8px;
    }
}

/* ===== HERO IMAGE STYLES ===== */
.post-hero-image {
    width: 100%;
    margin: 2rem 0;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.hero-image {
    width: 100%;
    height: 400px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.hero-image:hover {
    transform: scale(1.02);
}

/* Responsive hero image */
@media (max-width: 768px) {
    .hero-image {
        height: 250px;
    }
}

@media (max-width: 480px) {
    .hero-image {
        height: 200px;
    }
}

/* Post thumbnail trong danh sách */
.post-thumbnail {
    width: 100%;
    height: 240px;
    object-fit: cover;
    transition: transform 0.4s ease;
    border-radius: 0;
}

.post-card:hover .post-thumbnail {
    transform: scale(1.08);
}

@media (max-width: 768px) {
    .post-thumbnail {
        height: 200px;
    }
}

@media (max-width: 480px) {
    .post-thumbnail {
        height: 180px;
    }
}

/* Style cho links trong blog */
a {
    color: #667eea;
    text-decoration: none;
    font-weight: bold;
    transition: color 0.3s ease;
}

a:hover {
    color: #5a6fd8;
    text-decoration: underline;
}

/* Link mở tab mới */
a[target="_blank"]:after {
    content: " ↗";
    font-size: 0.8em;
}