```css
/* ===== CSS Reset & Base ===== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-light);
    color: var(--text-primary);
    line-height: 1.7;
    transition: background 0.4s ease, color 0.3s ease;
    overflow-x: hidden;
}

/* ===== CSS Variables ===== */
:root {
    --bg-light: #f0f4f8;
    --bg-card: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #475569;
    --text-heading: #0f172a;
    --text-link: #2563eb;
    --accent: #3b82f6;
    --accent-dark: #1d4ed8;
    --accent-glow: rgba(59, 130, 246, 0.25);
    --border-light: #e2e8f0;
    --footer-bg: #0b1220;
    --footer-text: #e2e8f0;
    --footer-link: #94a3b8;
    --dark-bg: #0f172a;
    --dark-card: #1e293b;
    --dark-text: #e2e8f0;
    --dark-heading: #f8fafc;
    --dark-secondary: #cbd5e1;
    --dark-border: #334155;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
    --shadow-md: 0 8px 24px rgba(0,0,0,0.06);
    --shadow-lg: 0 16px 40px rgba(0,0,0,0.08);
    --radius: 20px;
    --radius-sm: 12px;
    --blur: 20px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Dark Mode ===== */
[data-theme="dark"] {
    --bg-light: #0b1120;
    --bg-card: #1e293b;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-heading: #f8fafc;
    --text-link: #93c5fd;
    --border-light: #334155;
    --footer-bg: #0b1120;
    --footer-text: #cbd5e1;
    --footer-link: #64748b;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
    --shadow-md: 0 8px 24px rgba(0,0,0,0.4);
    --shadow-lg: 0 16px 40px rgba(0,0,0,0.5);
}

/* ===== Layout & Container ===== */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ===== Navbar ===== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: var(--bg-card);
    backdrop-filter: blur(var(--blur));
    -webkit-backdrop-filter: blur(var(--blur));
    box-shadow: var(--shadow-sm);
    border-bottom: 1px solid var(--border-light);
    transition: var(--transition);
}
.nav-wrap {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 0;
}
.logo {
    font-size: 1.9rem;
    font-weight: 800;
    color: var(--text-heading);
    text-decoration: none;
    letter-spacing: -0.5px;
    position: relative;
    transition: var(--transition);
}
.logo span {
    background: linear-gradient(135deg, var(--accent), #8b5cf6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.logo:hover { transform: scale(1.05); }
.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}
.nav-links a {
    color: var(--text-secondary);
    font-weight: 500;
    text-decoration: none;
    font-size: 1rem;
    position: relative;
    transition: color 0.2s;
}
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s;
}
.nav-links a:hover { color: var(--accent); }
.nav-links a:hover::after { width: 100%; }
.nav-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}
.search-box {
    display: flex;
    align-items: center;
    border: 1px solid var(--border-light);
    border-radius: 50px;
    background: var(--bg-light);
    padding: 4px 16px;
    transition: var(--transition);
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.02);
}
.search-box:focus-within {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}
.search-box input {
    border: none;
    background: transparent;
    padding: 8px;
    width: 180px;
    color: var(--text-primary);
    outline: none;
    font-size: 0.95rem;
}
.search-box input::placeholder {
    color: var(--text-secondary);
    opacity: 0.7;
}
.search-box button {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--text-primary);
    font-size: 1.2rem;
    padding: 4px;
    transition: transform 0.2s;
}
.search-box button:hover { transform: scale(1.15); }
.theme-toggle {
    background: var(--bg-light);
    border: 1px solid var(--border-light);
    border-radius: 50px;
    padding: 8px 16px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-size: 1rem;
}
.theme-toggle:hover {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
    transform: scale(1.05);
}
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.hamburger span {
    width: 28px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 4px;
    transition: var(--transition);
}
.mobile-menu {
    display: none;
    flex-direction: column;
    background: var(--bg-card);
    padding: 16px 24px;
    gap: 8px;
    border-top: 1px solid var(--border-light);
    backdrop-filter: blur(var(--blur));
}
.mobile-menu a {
    color: var(--text-primary);
    text-decoration: none;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-light);
    font-weight: 500;
    transition: color 0.2s;
}
.mobile-menu a:hover { color: var(--accent); }
.mobile-menu.open { display: flex; }

/* ===== Banner ===== */
.banner {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #312e81 100%);
    padding: 64px 0;
    margin-bottom: 40px;
    position: relative;
    overflow: hidden;
}
.banner::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, rgba(59,130,246,0.2) 0%, transparent 70%);
    pointer-events: none;
}
.banner::after {
    content: '';
    position: absolute;
    bottom: -50%;
    left: -20%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(139,92,246,0.15) 0%, transparent 70%);
    pointer-events: none;
}
.banner-content {
    display: flex;
    flex-wrap: wrap;
    gap: 40px;
    align-items: center;
    position: relative;
    z-index: 1;
}
.banner-text { flex: 1 1 300px; }
.banner-text h1 {
    color: #ffffff;
    font-size: 2.8rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
    text-shadow: 0 4px 20px rgba(0,0,0,0.3);
    letter-spacing: -1px;
}
.banner-text p {
    color: #e2e8f0;
    font-size: 1.15rem;
    max-width: 600px;
    margin-bottom: 32px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
    line-height: 1.8;
}
.btn-group {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}
.btn-primary {
    background: linear-gradient(135deg, #2563eb, #3b82f6);
    color: #ffffff;
    padding: 14px 32px;
    border-radius: 60px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    border: none;
    box-shadow: 0 4px 16px rgba(37, 99, 235, 0.3);
}
.btn-primary:hover {
    background: linear-gradient(135deg, #1d4ed8, #2563eb);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.4);
}
.btn-outline {
    border: 2px solid rgba(148, 163, 184, 0.6);
    color: #f8fafc;
    padding: 12px 30px;
    border-radius: 60px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    background: rgba(255,255,255,0.05);
    backdrop-filter: blur(10px);
}
.btn-outline:hover {
    border-color: #fff;
    color: #fff;
    background: rgba(255,255,255,0.1);
    transform: translateY(-2px);
}
.banner-visual {
    flex: 1 1 260px;
    display: flex;
    justify-content: center;
    animation: float 6s ease-in-out infinite;
}
.banner-visual svg {
    width: 300px;
    height: auto;
    filter: drop-shadow(0 20px 40px rgba(0,0,0,0.4));
}
@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

/* ===== Section General ===== */
.section { margin: 48px 0; }
.section-title {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-heading);
    margin-bottom: 32px;
    padding-left: 20px;
    position: relative;
    letter-spacing: -0.5px;
}
.section-title::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 6px;
    height: 60%;
    background: linear-gradient(180deg, var(--accent), #8b5cf6);
    border-radius: 4px;
}

/* ===== Cards ===== */
.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 28px;
}
.card {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
    border: 1px solid var(--border-light);
    position: relative;
    overflow: hidden;
}
.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), #8b5cf6);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.4s;
}
.card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}
.card:hover::before { transform: scaleX(1); }
.card h3 {
    font-size: 1.3rem;
    color: var(--text-heading);
    margin-bottom: 14px;
    font-weight: 700;
}
.card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.7;
    margin-bottom: 8px;
}
.card a {
    color: var(--accent);
    font-weight: 600;
    text-decoration: none;
    transition: color 0.2s;
    display: inline-block;
    margin-top: 8px;
}
.card a:hover { color: var(--accent-dark); }

/* ===== Article List ===== */
.article-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 24px;
}
.article-item {
    background: var(--bg-card);
    border-radius: 16px;
    padding: 24px;
    border: 1px solid var(--border-light);
    transition: var(--transition);
    position: relative;
}
.article-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}
.article-item time {
    color: var(--text-secondary);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.article-item h4 {
    color: var(--text-heading);
    margin: 12px 0 8px;
    font-size: 1.1rem;
    line-height: 1.5;
    transition: color 0.2s;
}
.article-item:hover h4 { color: var(--accent); }
.article-item p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.6;
}
.read-more {
    color: var(--accent);
    font-weight: 600;
    text-decoration: none;
    display: inline-block;
    margin-top: 12px;
    transition: all 0.2s;
}
.read-more:hover { color: var(--accent-dark); }

/* ===== FAQ ===== */
.faq-item {
    border-bottom: 1px solid var(--border-light);
    padding: 20px 0;
    transition: var(--transition);
}
.faq-question {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-heading);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    user-select: none;
    transition: color 0.2s;
}
.faq-question:hover { color: var(--accent); }
.faq-question span {
    font-size: 1.5rem;
    transition: transform 0.3s;
    flex-shrink: 0;
}
.faq-item.open .faq-question span { transform: rotate(45deg); }
.faq-answer {
    margin-top: 14px;
    color: var(--text-primary);
    padding-right: 20px;
    display: none;
    line-height: 1.8;
    animation: fadeIn 0.3s ease;
}
.faq-item.open .faq-answer { display: block; }
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-8px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ===== Table ===== */
.info-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-card);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}
.info-table th, .info-table td {
    padding: 16px 20px;
    text-align: left;
    border-bottom: 1px solid var(--border-light);
}
.info-table th {
    background: var(--bg-light);
    color: var(--text-heading);
    font-weight: 700;
    letter-spacing: 0.5px;
}
.info-table tr:hover td { background: var(--bg-light); }

/* ===== Footer ===== */
.footer {
    background: var(--footer-bg);
    color: var(--footer-text);
    padding: 56px 0 24px;
    margin-top: 64px;
    position: relative;
}
.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
}
.footer a {
    color: var(--footer-link);
    text-decoration: none;
    transition: color 0.2s;
}
.footer a:hover { color: #ffffff; }
.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
}
.footer h5 {
    color: #ffffff;
    margin-bottom: 20px;
    font-size: 1.1rem;
    font-weight: 700;
    position: relative;
    padding-bottom: 10px;
}
.footer h5::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 30px;
    height: 2px;
    background: var(--accent);
}
.footer p { line-height: 1.8; }
.footer-bottom {
    border-top: 1px solid rgba(51, 65, 85, 0.5);
    margin-top: 40px;
    padding-top: 24px;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 16px;
}
.footer-bottom p { color: var(--footer-link); }

/* ===== Back to Top ===== */
.back-to-top {
    position: fixed;
    bottom: 28px;
    right: 28px;
    background: linear-gradient(135deg, var(--accent), #8b5cf6);
    color: #fff;
    border: none;
    border-radius: 50%;
    width: 52px;
    height: 52px;
    font-size: 1.6rem;
    cursor: pointer;
    opacity: 0;
    transition: var(--transition);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.3);
    z-index: 999;
    display: flex;
    align-items: center;
    justify-content: center;
}
.back-to-top.show {
    opacity: 1;
    transform: translateY(0);
}
.back-to-top:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(37, 99, 235, 0.4);
}

/* ===== Scroll Animations ===== */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ===== Selection ===== */
::selection {
    background: var(--accent);
    color: #fff;
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}
::-webkit-scrollbar-track {
    background: var(--bg-light);
}
::-webkit-scrollbar-thumb {
    background: var(--border-light);
    border-radius: 10px;
    border: 2px solid var(--bg-light);
}
::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
}

/* ===== HowTo Section ===== */
#howto .card {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 32px;
    box-shadow: var(--shadow-md);
}
#howto .card ol {
    padding-left: 20px;
    color: var(--text-primary);
    line-height: 2;
}
#howto .card ol li {
    margin-bottom: 8px;
    position: relative;
}
#howto .card ol li::marker {
    color: var(--accent);
    font-weight: bold;
}
#howto .card strong {
    color: var(--accent);
}

/* ===== Contact Cards ===== */
#contact .card h3 {
    display: flex;
    align-items: center;
    gap: 8px;
}
#contact .card p {
    margin-bottom: 10px;
    padding-left: 12px;
    position: relative;
}
#contact .card p::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 4px;
    border-radius: 50%;
    background: var(--accent);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .container { padding: 0 16px; }
    .nav-links { display: none; }
    .hamburger { display: flex; }
    .search-box { width: auto; }
    .search-box input { width: 80px; }
    .banner { padding: 48px 0; }
    .banner-text h1 { font-size: 2rem; }
    .banner-text p { font-size: 1rem; }
    .section-title { font-size: 1.6rem; }
    .section { margin: 32px 0; }
    .grid-3 { gap: 20px; }
    .article-list { grid-template-columns: 1fr; }
    .footer-grid { gap: 24px; }
    .back-to-top {
        width: 44px;
        height: 44px;
        bottom: 20px;
        right: 20px;
        font-size: 1.4rem;
    }
}

/* ===== Small Screens ===== */
@media (max-width: 480px) {
    .banner-text h1 { font-size: 1.7rem; }
    .btn-group { flex-direction: column; }
    .btn-primary, .btn-outline { text-align: center; }
    .search-box input { width: 60px; }
    .search-box { padding: 4px 8px; }
    .theme-toggle { padding: 6px 10px; font-size: 0.9rem; }
}

/* ===== Utility ===== */
.text-secondary { color: var(--text-secondary) !important; }
.link { color: var(--text-link); }
.text-center { text-align: center; }
.mt-2 { margin-top: 16px; }
.mb-2 { margin-bottom: 16px; }
.hidden { display: none; }

/* ===== Print ===== */
@media print {
    .navbar, .footer, .back-to-top, .search-box, .theme-toggle, .hamburger { display: none; }
    body { background: #fff; color: #000; }
    .card, .article-item { box-shadow: none; border: 1px solid #ddd; }
}
```