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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Malgun Gothic", "Apple SD Gothic Neo", sans-serif;
    line-height: 1.6;
    color: #1a1a1a;
    background: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header {
    background: #fff;
    border-bottom: 1px solid #e0e0e0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo h1 {
    font-size: 1.5rem;
    color: #2563eb;
    display: inline;
    margin-right: 0.5rem;
}

.subtitle {
    color: #666;
    font-size: 0.9rem;
    font-weight: normal;
}

.menu {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.menu a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.2s;
}

.menu a:hover {
    color: #2563eb;
}

.btn-login {
    padding: 0.5rem 1.5rem;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    transition: background 0.2s;
}

.btn-login:hover {
    background: #1d4ed8;
}

/* Notice Banner */
.notice-banner {
    background: #fff3cd;
    border-bottom: 1px solid #ffc107;
    padding: 0.75rem;
    text-align: center;
    font-size: 0.9rem;
    color: #856404;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 0;
    text-align: center;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    line-height: 1.3;
}

.hero-description {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin: 3rem 0;
}

.stat {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-top: 2rem;
}

/* Buttons */
.btn {
    padding: 0.75rem 2rem;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-primary {
    background: white;
    color: #667eea;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.1);
}

.btn-large {
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
}

/* Sections */
.section {
    padding: 4rem 0;
    background: white;
}

.section-alt {
    background: #f9fafb;
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h3 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: #1a1a1a;
}

.section-header p {
    color: #666;
    font-size: 1.1rem;
}

/* Forum Section */
.forum-filters {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.filter-tag {
    padding: 0.5rem 1.25rem;
    border: 1px solid #e0e0e0;
    background: white;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s;
}

.filter-tag:hover {
    border-color: #2563eb;
    color: #2563eb;
}

.filter-tag.active {
    background: #2563eb;
    color: white;
    border-color: #2563eb;
}

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

.post-card {
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 1.5rem;
    transition: box-shadow 0.2s;
}

.post-card:hover {
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

.post-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.post-author {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.author-badge {
    padding: 0.25rem 0.75rem;
    background: #e5e7eb;
    border-radius: 4px;
    font-size: 0.8rem;
    font-weight: 600;
}

.author-badge.certified {
    background: #10b981;
    color: white;
}

.author-name {
    font-weight: 600;
    color: #1a1a1a;
}

.author-reputation {
    color: #666;
    font-size: 0.9rem;
}

.post-time {
    color: #999;
    font-size: 0.85rem;
}

.post-title {
    font-size: 1.2rem;
    color: #1a1a1a;
    margin-bottom: 1rem;
    font-weight: 600;
}

.post-tags {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.tag {
    padding: 0.25rem 0.75rem;
    background: #f3f4f6;
    border-radius: 4px;
    font-size: 0.85rem;
    color: #374151;
}

.post-meta {
    display: flex;
    gap: 1.5rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: #666;
}

.post-json-badge {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem;
    background: #f9fafb;
    border-radius: 6px;
    border: 1px solid #e5e7eb;
}

.post-json-badge code {
    font-family: 'Courier New', monospace;
    color: #2563eb;
    font-size: 0.85rem;
}

.btn-api-preview {
    padding: 0.5rem 1rem;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: background 0.2s;
}

.btn-api-preview:hover {
    background: #1d4ed8;
}

.btn-load-more {
    display: block;
    margin: 2rem auto 0;
    padding: 0.75rem 2rem;
    background: white;
    border: 2px solid #e0e0e0;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.2s;
}

.btn-load-more:hover {
    border-color: #2563eb;
    color: #2563eb;
}

/* Skills Market */
.skill-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
}

.skill-card {
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 12px;
    padding: 1.5rem;
    transition: all 0.2s;
}

.skill-card:hover {
    box-shadow: 0 8px 24px rgba(0,0,0,0.1);
    transform: translateY(-4px);
}

.skill-header {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: 1rem;
}

.skill-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: #1a1a1a;
    flex: 1;
}

.skill-price {
    font-size: 1.3rem;
    font-weight: 700;
    color: #2563eb;
    white-space: nowrap;
    margin-left: 1rem;
}

.skill-description {
    color: #666;
    margin-bottom: 1rem;
    line-height: 1.5;
}

.skill-tags {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.skill-author {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
    color: #666;
    font-size: 0.9rem;
}

.skill-stats {
    display: flex;
    justify-content: space-between;
    margin-bottom: 1rem;
    font-size: 0.85rem;
    color: #666;
}

.btn-skill-buy {
    width: 100%;
    padding: 0.75rem;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1rem;
    transition: background 0.2s;
}

.btn-skill-buy:hover {
    background: #1d4ed8;
}

/* API Section */
.api-examples {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.api-card {
    background: #1e293b;
    border-radius: 8px;
    padding: 1.5rem;
    position: relative;
}

.api-card h4 {
    color: #cbd5e1;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    font-weight: 600;
}

.api-card pre {
    background: #0f172a;
    padding: 1rem;
    border-radius: 6px;
    overflow-x: auto;
}

.api-card code {
    color: #86efac;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

.btn-copy {
    position: absolute;
    top: 1.5rem;
    right: 1.5rem;
    padding: 0.5rem 1rem;
    background: #334155;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: background 0.2s;
}

.btn-copy:hover {
    background: #475569;
}

.api-features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.feature-box {
    background: white;
    border: 1px solid #e0e0e0;
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
}

.feature-box h5 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.feature-box p {
    color: #666;
    line-height: 1.6;
}

/* About Section */
.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-vision {
    text-align: center;
    margin-bottom: 3rem;
    padding: 2rem;
    background: white;
    border-radius: 12px;
    border: 2px solid #e5e7eb;
}

.about-vision h4 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #1a1a1a;
}

.about-vision p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: #374151;
}

.about-vision strong {
    color: #2563eb;
    font-weight: 700;
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.about-card {
    background: white;
    border-radius: 8px;
    padding: 2rem;
    text-align: center;
    transition: all 0.2s;
}

.about-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0,0,0,0.1);
}

.about-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.about-card h5 {
    font-size: 1.1rem;
    margin-bottom: 0.75rem;
    color: #1a1a1a;
}

.about-card p {
    color: #666;
    line-height: 1.6;
}

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 4rem 0;
    text-align: center;
    color: white;
}

.cta-section h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.cta-section p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Footer */
.footer {
    background: #1a1a1a;
    color: #999;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    color: white;
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.footer-section h5 {
    color: #ccc;
    margin-bottom: 1rem;
    font-size: 1rem;
}

.footer-section p {
    line-height: 1.6;
}

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

.footer-section li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #999;
    text-decoration: none;
    transition: color 0.2s;
}

.footer-section a:hover {
    color: #2563eb;
}

.footer-bottom {
    border-top: 1px solid #333;
    padding-top: 2rem;
    text-align: center;
}

.footer-disclaimer {
    margin-top: 1rem;
    font-size: 0.9rem;
    color: #666;
}

/* Responsive */
@media (max-width: 768px) {
    .nav {
        flex-direction: column;
        gap: 1rem;
    }

    .menu {
        flex-wrap: wrap;
        justify-content: center;
    }

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

    .hero-stats {
        flex-direction: column;
        gap: 1.5rem;
    }

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

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