/* YI Hardware Lab - Modern Dark Engineering Theme */
:root {
    --bg-main: #0b0f19;
    --bg-surface: #121826;
    --bg-surface-elevated: #1a2336;
    --border-subtle: rgba(255, 255, 255, 0.08);
    --border-strong: rgba(255, 255, 255, 0.16);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --accent: #38bdf8;
    --accent-hover: #0284c7;
    --success: #10b981;
    --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
}

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

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.15s ease;
}

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

/* Header & Nav */
.site-header {
    background: rgba(11, 15, 25, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-subtle);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0.9rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-primary);
    font-weight: 600;
    font-size: 1.15rem;
}

.brand-symbol {
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: 1.4rem;
    align-items: center;
    font-size: 0.92rem;
}

.nav-links a {
    color: var(--text-secondary);
}

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

.lang-switch-btn {
    font-family: var(--font-mono);
    font-size: 0.82rem;
    padding: 0.25rem 0.6rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-subtle);
    border-radius: 4px;
    color: var(--accent) !important;
    transition: all 0.15s ease;
}

.lang-switch-btn:hover {
    background: var(--bg-surface-elevated);
    border-color: var(--accent);
}

.github-link {
    padding: 0.35rem 0.75rem;
    border: 1px solid var(--border-strong);
    border-radius: 6px;
    color: var(--text-primary) !important;
}

/* Hero Section */
.hero-section {
    border-bottom: 1px solid var(--border-subtle);
    padding: 4rem 1.5rem 3rem;
    background: radial-gradient(circle at 50% 0%, rgba(56, 189, 248, 0.08) 0%, transparent 70%);
}

.hero-container {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.hero-tag {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    letter-spacing: 0.15em;
    color: var(--accent);
    margin-bottom: 1rem;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1.25;
    margin-bottom: 1rem;
}

.hero-sub {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 720px;
    margin: 0 auto 2.5rem;
}

.stats-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    max-width: 800px;
    margin: 0 auto;
}

.stat-box {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    padding: 1.2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
    font-family: var(--font-mono);
}

.stat-label {
    font-size: 0.82rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

/* Main Container & Filters */
.main-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2.5rem 1.5rem 4rem;
}

.filter-toolbar {
    margin-bottom: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
}

.search-wrap input {
    width: 100%;
    padding: 0.85rem 1.2rem;
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    color: var(--text-primary);
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.15s ease;
}

.search-wrap input:focus {
    border-color: var(--accent);
}

.filter-groups {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.filter-group {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.5rem;
}

.filter-group-title {
    font-size: 0.85rem;
    color: var(--text-muted);
    min-width: 75px;
}

.filter-btn {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    padding: 0.35rem 0.75rem;
    border-radius: 6px;
    font-size: 0.82rem;
    cursor: pointer;
    transition: all 0.15s ease;
}

.filter-btn:hover {
    color: var(--text-primary);
    border-color: var(--border-strong);
}

.filter-btn.active {
    background: var(--accent);
    color: #041226;
    border-color: var(--accent);
    font-weight: 600;
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 1.5rem;
}

.project-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: 10px;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    transition: transform 0.15s ease, border-color 0.15s ease;
}

.project-card:hover {
    transform: translateY(-2px);
    border-color: var(--border-strong);
}

.card-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.8rem;
}

.mcu-badge {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--accent);
}

.cat-label, .ci-badge {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.card-title {
    font-size: 1.15rem;
    font-weight: 600;
    line-height: 1.4;
    margin-bottom: 0.6rem;
}

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

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

.card-summary {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
    flex-grow: 1;
    margin-bottom: 1.2rem;
}

.card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 1.2rem;
}

.mini-tag {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-subtle);
    padding: 0.15rem 0.45rem;
    border-radius: 4px;
    color: var(--text-secondary);
}

.card-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-top: 1px solid var(--border-subtle);
    padding-top: 0.9rem;
    font-size: 0.88rem;
}

.link-detail {
    font-weight: 500;
}

.link-faq {
    color: var(--text-muted);
}

.link-faq:hover {
    color: var(--text-primary);
}

/* Breadcrumbs */
.breadcrumb {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.breadcrumb .sep {
    color: var(--border-strong);
}

.breadcrumb .current {
    color: var(--text-secondary);
}

/* Article Detail Pages */
.article-detail {
    max-width: 900px;
    margin: 0 auto;
}

.detail-header {
    margin-bottom: 2.5rem;
}

.status-indicator {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--success);
    margin-bottom: 0.8rem;
}

.status-dot {
    width: 8px;
    height: 8px;
    background: var(--success);
    border-radius: 50%;
    box-shadow: 0 0 8px var(--success);
}

.project-title {
    font-size: 2.2rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 1rem;
}

.project-summary {
    font-size: 1.15rem;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.spec-tags-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.spec-tag {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    background: var(--bg-surface-elevated);
    border: 1px solid var(--border-subtle);
    padding: 0.25rem 0.65rem;
    border-radius: 5px;
    color: var(--text-primary);
}

.section-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: 10px;
    padding: 2rem;
    margin-bottom: 2rem;
}

.section-heading {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1.2rem;
}

.section-lead {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.specs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.2rem;
}

.spec-item {
    display: flex;
    flex-direction: column;
}

.spec-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 0.3rem;
}

.spec-value {
    font-size: 1rem;
    color: var(--text-primary);
    font-weight: 500;
}

.hardware-assets-checklist {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1rem;
}

.checklist-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: var(--bg-surface-elevated);
    padding: 0.9rem 1.1rem;
    border-radius: 6px;
    border: 1px solid var(--border-subtle);
}

.check-icon {
    color: var(--success);
    font-weight: bold;
}

.check-title {
    font-size: 0.9rem;
    color: var(--text-primary);
}

.boundaries-list {
    padding-left: 1.2rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

.boundaries-list li {
    margin-bottom: 0.5rem;
}

.faq-entry-link {
    margin-top: 1.5rem;
}

.card-link-btn {
    display: inline-block;
    color: var(--accent);
    font-weight: 500;
    font-size: 0.95rem;
}

/* FAQ Accordion */
.faq-accordion {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.faq-item {
    border-bottom: 1px solid var(--border-subtle);
    padding-bottom: 1.5rem;
}

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

.faq-question {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.6rem;
}

.faq-answer {
    color: var(--text-secondary);
    line-height: 1.7;
}

.back-project-link {
    margin-top: 2rem;
}

/* CTA Banner */
.cta-banner {
    background: linear-gradient(135deg, #151d30 0%, #1e293b 100%);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: 12px;
    padding: 2.2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 2rem;
    margin-top: 3rem;
}

.cta-banner h3 {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.cta-banner p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.cta-banner-actions {
    display: flex;
    gap: 1rem;
    flex-shrink: 0;
}

.btn {
    padding: 0.65rem 1.25rem;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.15s ease;
}

.btn-primary {
    background: var(--accent);
    color: #041226;
    border: 1px solid var(--accent);
}

.btn-primary:hover {
    background: var(--accent-hover);
    color: #ffffff;
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-strong);
}

.btn-secondary:hover {
    border-color: var(--text-primary);
}

.btn-whatsapp {
    background: #25D366;
    color: #041226;
    border: 1px solid #25D366;
    font-weight: 600;
}

.btn-whatsapp:hover {
    background: #1eb956;
    color: #ffffff;
}

/* Footer */
.site-footer {
    border-top: 1px solid var(--border-subtle);
    background: var(--bg-surface);
    padding: 3.5rem 1.5rem 2rem;
    margin-top: 5rem;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-title {
    font-weight: 600;
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.footer-sub {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.cta-box {
    background: var(--bg-surface-elevated);
    border: 1px solid var(--border-subtle);
    border-radius: 8px;
    padding: 1.5rem;
}

.cta-heading {
    font-weight: 600;
    font-size: 0.95rem;
    display: block;
    margin-bottom: 0.5rem;
}

.cta-text {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 1.2rem;
}

.cta-links {
    display: flex;
    gap: 0.8rem;
}

.footer-bottom {
    max-width: 1200px;
    margin: 0 auto;
    border-top: 1px solid var(--border-subtle);
    padding-top: 1.5rem;
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.no-results {
    text-align: center;
    padding: 4rem 1rem;
    color: var(--text-muted);
}

.hidden {
    display: none !important;
}

/* Responsive */
@media (max-width: 768px) {
    .stats-row {
        grid-template-columns: repeat(2, 1fr);
    }
    .projects-grid {
        grid-template-columns: 1fr;
    }
    .footer-container {
        grid-template-columns: 1fr;
    }
    .cta-banner {
        flex-direction: column;
        align-items: flex-start;
    }
    .hero-title {
        font-size: 2rem;
    }
}