* {
    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: #333;
    background-color: #f5f7fa;
}

.header-main {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo-link {
    text-decoration: none;
    color: white;
}

.logo-link h1 {
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: 1px;
}

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

.nav-menu a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
}

.nav-menu a:hover {
    opacity: 0.8;
}

.content-wrapper {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 2rem;
}

.hero-section {
    background: white;
    border-radius: 12px;
    padding: 3rem;
    margin-bottom: 2rem;
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
    text-align: center;
}

.hero-title {
    font-size: 2.5rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.hero-description {
    font-size: 1.1rem;
    color: #666;
    line-height: 1.8;
}

.section-title {
    font-size: 1.8rem;
    color: #333;
    margin-bottom: 1.5rem;
    padding-bottom: 0.5rem;
    border-bottom: 3px solid #667eea;
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.card-item {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.card-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 25px rgba(0,0,0,0.15);
}

.card-image {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.card-content {
    padding: 1.5rem;
}

.card-title {
    font-size: 1.3rem;
    color: #333;
    margin-bottom: 0.8rem;
}

.card-description {
    color: #666;
    font-size: 0.95rem;
    line-height: 1.6;
}

.card-link {
    display: inline-block;
    margin-top: 1rem;
    color: #667eea;
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s;
}

.card-link:hover {
    color: #764ba2;
}

.forum-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.forum-item {
    background: white;
    border-radius: 10px;
    padding: 2rem;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    display: flex;
    gap: 2rem;
    align-items: center;
    transition: transform 0.3s;
}

.forum-item:hover {
    transform: translateX(5px);
}

.forum-icon {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    object-fit: cover;
}

.forum-info {
    flex: 1;
}

.forum-title {
    font-size: 1.5rem;
    color: #333;
    margin-bottom: 0.5rem;
}

.forum-desc {
    color: #666;
    margin-bottom: 0.8rem;
}

.forum-stats {
    display: flex;
    gap: 2rem;
    color: #999;
    font-size: 0.9rem;
}

.post-detail {
    background: white;
    border-radius: 10px;
    padding: 2.5rem;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    margin-bottom: 2rem;
}

.post-header {
    margin-bottom: 2rem;
    padding-bottom: 1.5rem;
    border-bottom: 2px solid #f0f0f0;
}

.post-title-main {
    font-size: 2rem;
    color: #333;
    margin-bottom: 1rem;
}

.post-meta {
    display: flex;
    gap: 2rem;
    color: #999;
    font-size: 0.9rem;
}

.post-body {
    line-height: 1.8;
    color: #444;
    margin-bottom: 2rem;
}

.post-body p {
    margin-bottom: 1rem;
}

.post-images {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 1rem;
    margin: 2rem 0;
}

.post-images img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-radius: 8px;
}

.comment-section {
    background: white;
    border-radius: 10px;
    padding: 2.5rem;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
}

.comment-item {
    padding: 1.5rem;
    border-bottom: 1px solid #f0f0f0;
}

.comment-item:last-child {
    border-bottom: none;
}

.comment-author {
    font-weight: 600;
    color: #667eea;
    margin-bottom: 0.5rem;
}

.comment-content {
    color: #666;
    line-height: 1.6;
}

.form-container {
    background: white;
    border-radius: 10px;
    padding: 2.5rem;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
}

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

.form-label {
    display: block;
    font-weight: 600;
    color: #333;
    margin-bottom: 0.5rem;
}

.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: 0.8rem;
    border: 2px solid #e0e0e0;
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
    outline: none;
    border-color: #667eea;
}

.form-textarea {
    min-height: 200px;
    resize: vertical;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem 2.5rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.4);
}

.footer-main {
    background: #2d3748;
    color: white;
    padding: 3rem 0 1.5rem;
    margin-top: 4rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    text-align: center;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.footer-links a {
    color: #cbd5e0;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: white;
}

.footer-copyright {
    color: #a0aec0;
    font-size: 0.9rem;
}

.user-profile {
    background: white;
    border-radius: 10px;
    padding: 2.5rem;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    margin-bottom: 2rem;
}

.profile-header {
    display: flex;
    align-items: center;
    gap: 2rem;
    margin-bottom: 2rem;
    padding-bottom: 2rem;
    border-bottom: 2px solid #f0f0f0;
}

.profile-avatar {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    object-fit: cover;
}

.profile-info h2 {
    font-size: 1.8rem;
    color: #333;
    margin-bottom: 0.5rem;
}

.profile-stats {
    display: flex;
    gap: 2rem;
    color: #666;
}

.user-posts {
    margin-top: 2rem;
}

.user-post-item {
    padding: 1.5rem;
    border-bottom: 1px solid #f0f0f0;
    transition: background 0.3s;
}

.user-post-item:hover {
    background: #f9fafb;
}

.user-post-title {
    font-size: 1.2rem;
    color: #667eea;
    margin-bottom: 0.5rem;
    text-decoration: none;
    display: block;
}

.user-post-title:hover {
    text-decoration: underline;
}

.user-post-meta {
    color: #999;
    font-size: 0.9rem;
}

.sidebar-widget {
    background: white;
    border-radius: 10px;
    padding: 1.5rem;
    box-shadow: 0 2px 15px rgba(0,0,0,0.08);
    margin-bottom: 1.5rem;
}

.widget-title {
    font-size: 1.2rem;
    color: #333;
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 2px solid #667eea;
}

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

.widget-list li {
    padding: 0.8rem 0;
    border-bottom: 1px solid #f0f0f0;
}

.widget-list li:last-child {
    border-bottom: none;
}

.widget-list a {
    color: #666;
    text-decoration: none;
    transition: color 0.3s;
}

.widget-list a:hover {
    color: #667eea;
}

@media (max-width: 768px) {
    .nav-menu {
        gap: 1rem;
        font-size: 0.9rem;
    }

    .hero-title {
        font-size: 1.8rem;
    }

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

    .forum-item {
        flex-direction: column;
        text-align: center;
    }

    .profile-header {
        flex-direction: column;
        text-align: center;
    }
}