/**
 * Fred Zhou Website - Main Stylesheet
 * Brand: Warm, philosophical, professional
 */

/* ===== CSS Variables ===== */
:root {
    --color-primary: #1e3a5f;
    --color-secondary: #c9a227;
    --color-accent: #4a7c59;
    --color-background: #faf9f7;
    --color-text: #2c3e50;

    --font-heading: 'Playfair Display', Georgia, serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;

    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;

    --max-width: 1200px;
    --max-width-narrow: 800px;

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);

    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;

    --transition: 0.2s ease;
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

body {
    font-family: var(--font-body);
    font-size: 1rem;
    line-height: 1.7;
    color: var(--color-text);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-primary);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

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

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

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

/* ===== Layout ===== */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.container--narrow {
    max-width: var(--max-width-narrow);
}

.main-content {
    min-height: calc(100vh - 200px);
}

/* ===== Buttons ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: 0.75rem 1.5rem;
    font-family: var(--font-body);
    font-size: 0.95rem;
    font-weight: 500;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition);
}

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

.btn-primary:hover {
    background-color: #15293f;
    color: white;
}

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

.btn-secondary:hover {
    background-color: #a88520;
    color: white;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

/* ===== Header ===== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: white;
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
}

.site-logo {
    display: flex;
    flex-direction: column;
}

.logo-name {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
}

.logo-tagline {
    font-size: 0.75rem;
    color: #666;
    letter-spacing: 0.02em;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.main-nav a {
    font-weight: 500;
    padding: var(--spacing-xs) 0;
    position: relative;
}

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

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

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    transition: var(--transition);
}

/* ===== Hero Section ===== */
.hero {
    padding: var(--spacing-2xl) 0;
    background: linear-gradient(135deg, var(--color-primary) 0%, #2c4a6e 100%);
    color: white;
}

.hero__content {
    max-width: 700px;
}

.hero__title {
    font-size: 3.5rem;
    color: white;
    margin-bottom: var(--spacing-xs);
}

.hero__subtitle {
    font-size: 1.5rem;
    font-style: italic;
    color: var(--color-secondary);
    margin-bottom: var(--spacing-md);
}

.hero__description {
    font-size: 1.125rem;
    opacity: 0.9;
    margin-bottom: var(--spacing-lg);
    line-height: 1.8;
}

/* ===== Sections ===== */
.section-title {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-lg);
}

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

.view-all {
    color: var(--color-secondary);
    font-weight: 500;
}

.featured-post,
.recent-posts,
.values-section,
.cta-section {
    padding: var(--spacing-2xl) 0;
}

.recent-posts {
    background: white;
}

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

.posts-grid--3 {
    grid-template-columns: repeat(3, 1fr);
}

.post-card {
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition), transform var(--transition);
}

.post-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-4px);
}

.post-card__image {
    display: block;
    aspect-ratio: 16/9;
    overflow: hidden;
}

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

.post-card:hover .post-card__image img {
    transform: scale(1.05);
}

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

.post-card__category {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.post-card__title {
    font-size: 1.25rem;
    margin: var(--spacing-xs) 0 var(--spacing-sm);
}

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

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

.post-card__excerpt {
    color: #666;
    font-size: 0.95rem;
    margin-bottom: var(--spacing-sm);
}

.post-card__meta {
    font-size: 0.8rem;
    color: #888;
}

.meta-separator {
    margin: 0 0.5rem;
}

.post-card--featured {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
}

.post-card--featured .post-card__image {
    aspect-ratio: auto;
    height: 100%;
}

/* ===== Values Section ===== */
.values-section {
    background: var(--color-background);
}

.values-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.value-card {
    text-align: center;
    padding: var(--spacing-lg);
}

.value-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}

.value-icon svg {
    width: 32px;
    height: 32px;
}

.value-icon.family {
    background: rgba(30, 58, 95, 0.1);
    color: var(--color-primary);
}

.value-icon.health {
    background: rgba(74, 124, 89, 0.1);
    color: var(--color-accent);
}

.value-icon.wealth {
    background: rgba(201, 162, 39, 0.1);
    color: var(--color-secondary);
}

.value-card h3 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
}

.value-card p {
    color: #666;
}

/* ===== CTA Section ===== */
.cta-section {
    background: var(--color-primary);
    color: white;
}

.cta-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.cta-content h2 {
    color: white;
    margin-bottom: var(--spacing-sm);
}

.cta-content p {
    margin-bottom: var(--spacing-lg);
    opacity: 0.9;
}

/* ===== Blog Page ===== */
.blog-header {
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
    text-align: center;
}

.blog-subtitle {
    color: #666;
    font-size: 1.125rem;
}

.blog-layout {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: var(--spacing-2xl);
    padding-bottom: var(--spacing-2xl);
}

.blog-main {
    min-width: 0;
}

.blog-search {
    margin-bottom: var(--spacing-lg);
}

.search-form {
    display: flex;
    gap: var(--spacing-sm);
}

.search-input {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid #ddd;
    border-radius: var(--radius-md);
    font-size: 1rem;
}

.search-button {
    padding: 0.75rem 1rem;
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
}

.search-button svg {
    width: 20px;
    height: 20px;
}

.posts-list .post-card {
    margin-bottom: var(--spacing-lg);
}

/* ===== Blog Sidebar ===== */
.blog-sidebar {
    position: sticky;
    top: 100px;
    align-self: start;
}

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

.sidebar-widget h3 {
    font-size: 1rem;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--color-secondary);
}

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

.category-list li {
    margin-bottom: var(--spacing-xs);
}

.category-list a {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-xs) 0;
}

.category-color {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.tag-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

.tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: var(--color-background);
    border-radius: 20px;
    font-size: 0.85rem;
}

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

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

.sidebar-cta h3 {
    color: white;
    border-color: var(--color-secondary);
}

.sidebar-cta p {
    margin-bottom: var(--spacing-sm);
    opacity: 0.9;
}

/* ===== Single Post ===== */
.post-header {
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.post-category {
    font-size: 0.85rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.post-title {
    font-size: 2.75rem;
    margin: var(--spacing-md) 0;
}

.post-meta {
    color: #666;
}

.post-featured-image {
    margin-bottom: var(--spacing-xl);
}

.post-featured-image img {
    width: 100%;
    max-height: 500px;
    object-fit: cover;
    border-radius: var(--radius-lg);
}

.post-content {
    padding-bottom: var(--spacing-2xl);
}

.content-body {
    font-size: 1.125rem;
    line-height: 1.9;
}

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

.content-body h2 {
    margin: var(--spacing-xl) 0 var(--spacing-md);
}

.content-body h3 {
    margin: var(--spacing-lg) 0 var(--spacing-sm);
}

.content-body blockquote {
    margin: var(--spacing-lg) 0;
    padding: var(--spacing-md) var(--spacing-lg);
    border-left: 4px solid var(--color-secondary);
    background: rgba(201, 162, 39, 0.08);
    font-style: italic;
}

.content-body ul, .content-body ol {
    margin: var(--spacing-md) 0 var(--spacing-md) var(--spacing-lg);
}

.content-body li {
    margin-bottom: var(--spacing-xs);
}

.content-body a {
    color: var(--color-secondary);
    text-decoration: underline;
}

.post-tags {
    margin: var(--spacing-xl) 0;
    padding: var(--spacing-md) 0;
    border-top: 1px solid #eee;
    border-bottom: 1px solid #eee;
}

.tags-label {
    font-weight: 500;
    margin-right: var(--spacing-sm);
}

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

.author-box {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--color-background);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.author-info h4 {
    margin-bottom: var(--spacing-xs);
}

.author-info p {
    color: #666;
    font-size: 0.95rem;
}

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

.share-links > span {
    font-weight: 500;
}

.share-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 0.5rem 1rem;
    background: var(--color-background);
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    cursor: pointer;
}

.share-link:hover {
    background: var(--color-primary);
    color: white;
}

.related-posts {
    background: white;
    padding: var(--spacing-2xl) 0;
}

.related-posts h2 {
    text-align: center;
    margin-bottom: var(--spacing-lg);
}

/* ===== About Page ===== */
.about-hero {
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
    text-align: center;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 300px;
    gap: var(--spacing-2xl);
    padding-bottom: var(--spacing-2xl);
}

.about-main {
    min-width: 0;
}

.content-block {
    margin-bottom: var(--spacing-xl);
}

.content-block h2 {
    margin-bottom: var(--spacing-md);
}

.content-block p {
    margin-bottom: var(--spacing-md);
}

.content-block ul {
    margin-left: var(--spacing-lg);
}

.content-block li {
    margin-bottom: var(--spacing-xs);
}

.about-sidebar {
    position: sticky;
    top: 100px;
    align-self: start;
}

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

.sidebar-card h3 {
    font-size: 1rem;
    margin-bottom: var(--spacing-md);
}

.sidebar-card p {
    font-size: 0.95rem;
    color: #666;
    margin-bottom: var(--spacing-md);
}

.connect-links {
    list-style: none;
}

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

.connect-links a {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

/* ===== Contact Page ===== */
.contact-header {
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
    text-align: center;
}

.contact-intro {
    max-width: 600px;
    margin: 0 auto;
    color: #666;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: var(--spacing-2xl);
    padding-bottom: var(--spacing-2xl);
}

.contact-form {
    background: white;
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
}

.form-group {
    margin-bottom: var(--spacing-md);
}

.form-group label {
    display: block;
    font-weight: 500;
    margin-bottom: var(--spacing-xs);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #ddd;
    border-radius: var(--radius-md);
    font-family: var(--font-body);
    font-size: 1rem;
    transition: border-color var(--transition);
    background-color: white;
}

.form-group select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23666' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
    padding-right: 2.5rem;
    cursor: pointer;
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--color-primary);
}

.form-group textarea {
    resize: vertical;
}

.error-message {
    display: block;
    color: #dc3545;
    font-size: 0.85rem;
    margin-top: var(--spacing-xs);
}

.form-actions {
    margin-top: var(--spacing-lg);
}

.form-actions .btn {
    width: 100%;
}

.form-status {
    margin-top: var(--spacing-md);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    display: none;
}

.form-status.success {
    display: block;
    background: rgba(74, 124, 89, 0.1);
    color: var(--color-accent);
}

.form-status.error {
    display: block;
    background: rgba(220, 53, 69, 0.1);
    color: #dc3545;
}

.form-note {
    margin-top: var(--spacing-md);
    font-size: 0.9rem;
    color: #888;
    text-align: center;
}

.contact-sidebar {
    position: sticky;
    top: 100px;
    align-self: start;
}

.contact-info-card,
.contact-cta-card {
    background: white;
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    margin-bottom: var(--spacing-md);
}

.contact-info-card h3,
.contact-cta-card h3 {
    font-size: 1rem;
    margin-bottom: var(--spacing-md);
}

.contact-methods {
    list-style: none;
}

.contact-methods li {
    display: flex;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid #eee;
}

.contact-methods li:last-child {
    border-bottom: none;
}

.contact-methods svg {
    width: 20px;
    height: 20px;
    color: var(--color-primary);
    flex-shrink: 0;
    margin-top: 2px;
}

.contact-methods strong {
    display: block;
    font-size: 0.85rem;
    color: #888;
}

.contact-cta-card p {
    font-size: 0.95rem;
    color: #666;
    margin-bottom: var(--spacing-sm);
}

/* ===== 404 Page ===== */
.error-page {
    padding: var(--spacing-2xl) 0;
    text-align: center;
    min-height: 60vh;
    display: flex;
    align-items: center;
}

.error-content h1 {
    font-size: 8rem;
    color: var(--color-secondary);
    line-height: 1;
}

.error-content h2 {
    margin-bottom: var(--spacing-md);
}

.error-content p {
    color: #666;
    margin-bottom: var(--spacing-lg);
}

.error-links {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    flex-wrap: wrap;
}

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

.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-signature {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-style: italic;
    color: var(--color-secondary);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.footer-links h4 {
    color: white;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
}

.footer-links ul {
    list-style: none;
}

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

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
}

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

.footer-bottom {
    text-align: center;
    padding-top: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    font-size: 0.9rem;
    opacity: 0.7;
}

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

.page-link {
    padding: 0.5rem 1rem;
    background: white;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

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

.page-info {
    color: #888;
}

/* ===== Empty State ===== */
.empty-state {
    text-align: center;
    padding: var(--spacing-2xl);
    color: #888;
}

.empty-state svg {
    width: 64px;
    height: 64px;
    margin-bottom: var(--spacing-md);
    opacity: 0.5;
}

.empty-state h3 {
    color: #666;
    margin-bottom: var(--spacing-sm);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
    .blog-layout,
    .about-grid,
    .contact-grid {
        grid-template-columns: 1fr;
    }

    .blog-sidebar,
    .about-sidebar,
    .contact-sidebar {
        position: static;
    }

    .values-grid,
    .posts-grid--3 {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }

    .footer-links {
        grid-template-columns: repeat(3, 1fr);
    }

    .post-card--featured {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    html {
        font-size: 15px;
    }

    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }

    .hero__title {
        font-size: 2.5rem;
    }

    .hero__subtitle {
        font-size: 1.25rem;
    }

    .post-title {
        font-size: 2rem;
    }

    .main-nav {
        display: none;
        position: absolute;
        top: 80px;
        left: 0;
        right: 0;
        background: white;
        border-bottom: 1px solid #eee;
        padding: var(--spacing-md);
    }

    .main-nav.open {
        display: block;
    }

    .main-nav ul {
        flex-direction: column;
        gap: var(--spacing-sm);
    }

    .mobile-menu-toggle {
        display: flex;
    }

    .mobile-menu-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }

    .mobile-menu-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .mobile-menu-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -5px);
    }

    .footer-links {
        grid-template-columns: 1fr 1fr;
    }

    .posts-grid {
        grid-template-columns: 1fr;
    }

    .share-links {
        flex-direction: column;
        align-items: flex-start;
    }
}