:root {
    --bg-deep: #0a192f;
    --bg-mid: #112240;
    --accent-amber: #f5af19;
    --accent-cyan: #00f2ff;
    --accent-rose: #f12711;
    --text-primary: #e6f1ff;
    --text-secondary: #8892b0;
    --glass-bg: rgba(17, 34, 64, 0.6);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glow-amber: 0 0 20px rgba(245, 175, 25, 0.4);
    --glow-cyan: 0 0 20px rgba(0, 242, 255, 0.3);
    --font-main: 'Segoe UI', system-ui, -apple-system, sans-serif;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    background-color: var(--bg-deep);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
    position: relative;
}

.ambient-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: radial-gradient(circle at 10% 20%, rgba(245, 175, 25, 0.15) 0%, transparent 40%),
                radial-gradient(circle at 90% 80%, rgba(0, 242, 255, 0.1) 0%, transparent 40%);
    z-index: -2;
    pointer-events: none;
}

.particles-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    overflow: hidden;
}

.particle-dot {
    position: absolute;
    background: var(--accent-cyan);
    border-radius: 50%;
    opacity: 0.3;
    animation: float-particle 15s infinite linear;
}

@keyframes float-particle {
    0% { transform: translateY(100vh) translateX(0); opacity: 0; }
    10% { opacity: 0.5; }
    90% { opacity: 0.5; }
    100% { transform: translateY(-10vh) translateX(20px); opacity: 0; }
}

.glass-header {
    position: fixed;
    top: 0;
    width: 100%;
    padding: 1rem 5%;
    background: rgba(10, 25, 47, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--glass-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent-amber), var(--accent-rose));
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    color: white;
    box-shadow: var(--glow-amber);
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    background: linear-gradient(to right, var(--text-primary), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

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

.desktop-nav a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: var(--transition);
}

.desktop-nav a:hover {
    color: var(--accent-cyan);
}

.cta-button {
    padding: 0.6rem 1.2rem;
    background: transparent;
    border: 1px solid var(--accent-amber);
    color: var(--accent-amber) !important;
    border-radius: 4px;
    transition: var(--transition);
}

.cta-button:hover {
    background: rgba(245, 175, 25, 0.1);
    box-shadow: var(--glow-amber);
}

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

.mobile-menu-btn span {
    width: 25px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

.mobile-nav {
    position: fixed;
    top: 70px;
    left: 0;
    width: 100%;
    background: rgba(10, 25, 47, 0.95);
    backdrop-filter: blur(12px);
    padding: 2rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    transform: translateY(-150%);
    transition: transform 0.4s ease;
    z-index: 999;
    border-bottom: 1px solid var(--glass-border);
}

.mobile-nav.active {
    transform: translateY(0);
}

.mobile-nav a {
    color: var(--text-primary);
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 600;
}

.layout-container {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 3rem;
    max-width: 1200px;
    margin: 100px auto 4rem;
    padding: 0 2rem;
}

.toc-sidebar {
    position: sticky;
    top: 100px;
    height: fit-content;
}

.toc-container {
    padding: 1.5rem;
    border-radius: 12px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(10px);
}

.toc-container h3 {
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--accent-cyan);
    margin-bottom: 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--glass-border);
}

#toc-list {
    list-style: none;
}

#toc-list li {
    margin-bottom: 0.5rem;
}

.toc-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.9rem;
    display: block;
    padding: 0.4rem 0.8rem;
    border-radius: 4px;
    border-left: 2px solid transparent;
    transition: var(--transition);
}

.toc-link:hover, .toc-link.active {
    color: var(--text-primary);
    background: rgba(0, 242, 255, 0.05);
    border-left-color: var(--accent-cyan);
}

.content-area {
    min-width: 0;
}

.hero-section {
    margin-bottom: 4rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.hero-visual {
    position: relative;
    height: 400px;
    display: flex;
    align-items: center;
    justify-content: center;
    perspective: 1000px;
}

.animation-stage {
    position: relative;
    width: 300px;
    height: 300px;
    transform-style: preserve-3d;
    transition: transform 0.1s ease-out;
}

.cabinet-svg {
    width: 100%;
    height: 100%;
    filter: drop-shadow(0 0 15px rgba(245, 175, 25, 0.3));
    animation: cabinet-float 6s ease-in-out infinite;
}

@keyframes cabinet-float {
    0%, 100% { transform: translateY(0) rotateY(0deg); }
    50% { transform: translateY(-15px) rotateY(5deg); }
}

.cabinet-door {
    animation: door-fill 4s ease-in-out infinite alternate;
}

@keyframes door-fill {
    0% { fill: rgba(245, 175, 25, 0.1); stroke: rgba(245, 175, 25, 0.5); }
    50% { fill: rgba(245, 175, 25, 0.3); stroke: rgba(245, 175, 25, 0.8); }
    100% { fill: url(#amber-gradient); stroke: var(--accent-amber); }
}

.sanding-particles .particle {
    animation: sand 3s infinite linear;
}

.p1 { animation-delay: 0s; }
.p2 { animation-delay: 0.5s; }
.p3 { animation-delay: 1s; }
.p4 { animation-delay: 1.5s; }
.p5 { animation-delay: 2s; }

@keyframes sand {
    0% { transform: translate(0, 0); opacity: 0; }
    20% { opacity: 1; }
    80% { opacity: 1; }
    100% { transform: translate(20px, -20px); opacity: 0; }
}

.brush-stroke {
    animation: brush 4s ease-in-out infinite alternate;
}

@keyframes brush {
    0% { opacity: 0; pathLength: 0; }
    50% { opacity: 0.8; pathLength: 0.5; }
    100% { opacity: 1; pathLength: 1; }
}

.glow-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(40px);
    z-index: -1;
}

.orb-1 {
    width: 150px;
    height: 150px;
    background: var(--accent-amber);
    top: 20%;
    left: 10%;
    animation: orb-move 8s infinite alternate;
}

.orb-2 {
    width: 100px;
    height: 100px;
    background: var(--accent-cyan);
    bottom: 20%;
    right: 10%;
    animation: orb-move 6s infinite alternate-reverse;
}

@keyframes orb-move {
    0% { transform: translate(0, 0); }
    100% { transform: translate(30px, -30px); }
}

.rotating-rings {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 250px;
    height: 250px;
    pointer-events: none;
}

.ring {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 1px solid rgba(0, 242, 255, 0.3);
    border-radius: 50%;
    border-top-color: var(--accent-cyan);
}

.ring-1 { animation: spin 10s linear infinite; }
.ring-2 { animation: spin 15s linear infinite reverse; width: 80%; height: 80%; top: 10%; left: 10%; border-color: rgba(245, 175, 25, 0.3); border-top-color: var(--accent-amber); }
.ring-3 { animation: spin 20s linear infinite; width: 120%; height: 120%; top: -10%; left: -10%; border-style: dashed; }

@keyframes spin {
    to { transform: rotate(360deg); }
}

.hero-text-reveal {
    position: absolute;
    bottom: -20px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    width: 100%;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -1px;
    text-shadow: 0 0 20px rgba(0, 242, 255, 0.5);
}

.hero-title .highlight {
    color: var(--accent-amber);
}

.hero-subtitle {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-top: 0.5rem;
}

.hero-content h1 {
    font-size: 2.8rem;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    background: linear-gradient(to right, var(--text-primary), var(--accent-cyan));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.lead {
    font-size: 1.15rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

.keyword-link {
    color: var(--accent-amber);
    text-decoration: none;
    border-bottom: 1px dashed var(--accent-amber);
    transition: var(--transition);
}

.keyword-link:hover {
    color: var(--accent-cyan);
    border-bottom-color: var(--accent-cyan);
    text-shadow: var(--glow-cyan);
}

.content-section {
    margin-bottom: 3rem;
}

.content-section h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
    position: relative;
    padding-left: 1rem;
}

.content-section h2::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 70%;
    background: linear-gradient(to bottom, var(--accent-amber), var(--accent-cyan));
    border-radius: 2px;
}

.content-section h3 {
    font-size: 1.4rem;
    margin: 2rem 0 1rem;
    color: var(--accent-cyan);
}

.content-section p {
    margin-bottom: 1.2rem;
    color: var(--text-secondary);
}

.feature-list, .takeaway-list {
    list-style: none;
    margin: 1.5rem 0;
}

.feature-list li, .takeaway-list li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.8rem;
    color: var(--text-secondary);
}

.feature-list li::before {
    content: '▹';
    position: absolute;
    left: 0;
    color: var(--accent-amber);
}

.takeaway-list li::before {
    content: '★';
    position: absolute;
    left: 0;
    color: var(--accent-cyan);
}

.step-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 2rem;
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.step-card:hover {
    border-color: rgba(0, 242, 255, 0.3);
    box-shadow: var(--glow-cyan);
    transform: translateY(-5px);
}

.glass-card {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    backdrop-filter: blur(12px);
}

.cta-section {
    padding: 4rem 2rem;
    display: flex;
    justify-content: center;
}

.cta-card {
    max-width: 800px;
    width: 100%;
    padding: 3rem;
    text-align: center;
    border: 1px solid rgba(245, 175, 25, 0.3);
    box-shadow: 0 0 40px rgba(245, 175, 25, 0.1);
}

.cta-card h2 {
    font-size: 2.2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.cta-card > p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
    text-align: left;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    color: var(--text-secondary);
}

.contact-item svg {
    width: 20px;
    height: 20px;
    color: var(--accent-amber);
    flex-shrink: 0;
}

.contact-item a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
}

.contact-item a:hover {
    color: var(--accent-cyan);
}

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

.social-links a {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-primary);
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--accent-amber);
    color: var(--bg-deep);
    box-shadow: var(--glow-amber);
    transform: translateY(-3px);
}

.social-links svg {
    width: 24px;
    height: 24px;
}

.primary-btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    background: linear-gradient(135deg, var(--accent-amber), var(--accent-rose));
    color: white;
    text-decoration: none;
    font-weight: 700;
    border-radius: 8px;
    transition: var(--transition);
    box-shadow: 0 4px 15px rgba(245, 175, 25, 0.3);
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(245, 175, 25, 0.5);
}

.glass-footer {
    text-align: center;
    padding: 2rem;
    border-top: 1px solid var(--glass-border);
    color: var(--text-secondary);
    font-size: 0.9rem;
    background: rgba(10, 25, 47, 0.8);
    backdrop-filter: blur(10px);
}

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 968px) {
    .layout-container {
        grid-template-columns: 1fr;
    }
    
    .toc-sidebar {
        display: none;
    }
    
    .hero-section {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-visual {
        height: 300px;
        order: -1;
    }
    
    .hero-content h1 {
        font-size: 2.2rem;
    }
}

@media (max-width: 768px) {
    .desktop-nav {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
    }
    
    .cta-card {
        padding: 2rem 1.5rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    .fade-in {
        opacity: 1;
        transform: none;
    }
}