:root {
    --bg-color: #0a0a0a;
    --surface-color: #1a1a1a;
    --primary-color: #7c3aed;
    /* Electric Purple */
    --primary-glow: rgba(124, 58, 237, 0.5);
    --text-color: #ffffff;
    --text-secondary: #a1a1aa;
    --font-main: 'Inter', sans-serif;
    --font-kr: 'Noto Sans KR', sans-serif;
    --transition: all 0.3s ease;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-kr), var(--font-main);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Typography */
h1,
h2,
h3,
h4,
h5 {
    font-family: var(--font-main);
    font-weight: 800;
    letter-spacing: -0.02em;
}

a {
    text-decoration: none;
    color: inherit;
}

/* Accessibility - Keyboard Focus Styles */
a:focus,
button:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

a:focus-visible,
button:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

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

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

.slide-up {
    opacity: 0;
    transform: translateY(50px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.slide-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Navbar */
.navbar {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    padding: 1.5rem 2rem;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    background: rgba(10, 10, 10, 0.8);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
}

.logo {
    font-weight: 800;
    font-size: 1.5rem;
    letter-spacing: -0.05em;
    color: var(--text-color);
    transition: var(--transition);
}

.nav-links {
    display: flex;
    gap: 2rem;
    justify-content: center;
}

.nav-links a {
    color: var(--text-secondary);
    font-weight: 500;
    transition: var(--transition);
}

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

.nav-right {
    display: flex;
    align-items: center;
    gap: 1rem;
    justify-self: end;
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--text-secondary);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    cursor: pointer;
    font-family: var(--font-main);
    font-weight: 600;
    transition: var(--transition);
}

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

/* Hamburger Menu Button */
.menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 101;
}

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

.menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(7px, 7px);
}

.menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: 0 2rem;
    text-align: center;
    overflow: hidden;
}

.hero-content {
    z-index: 2;
    max-width: 800px;
}

h1.glitch {
    font-size: 5rem;
    margin-bottom: 1rem;
    position: relative;
    text-shadow: 0 0 20px var(--primary-glow);
}

.subtitle {
    font-size: 1.5rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
}

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

.btn {
    padding: 1rem 2rem;
    border-radius: 30px;
    font-weight: 600;
    transition: var(--transition);
    display: inline-block;
}

.btn.primary {
    background: var(--primary-color);
    color: white;
    box-shadow: 0 0 20px var(--primary-glow);
    border: none;
}

.btn.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 40px var(--primary-glow);
}

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

.btn.secondary:hover {
    border-color: var(--text-color);
    background: rgba(255, 255, 255, 0.05);
}

.btn.small {
    padding: 0.8rem 1.5rem;
    font-size: 0.9rem;
}

/* Abstract Visual */
.pulse-circle {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: radial-gradient(circle, var(--primary-glow) 0%, transparent 70%);
    opacity: 0.2;
    z-index: 1;
    filter: blur(80px);
    animation: pulse 6s infinite ease-in-out;
}

@keyframes pulse {
    0% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.2;
    }

    50% {
        transform: translate(-50%, -50%) scale(1.3);
        opacity: 0.4;
    }

    100% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.2;
    }
}

/* About Section */
.about {
    padding: 8rem 2rem;
    background: var(--bg-color);
    text-align: center;
}

.about-text {
    font-size: 1.5rem;
    color: var(--text-secondary);
    max-width: 800px;
    margin: 0 auto 4rem auto;
    white-space: pre-line;
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.about-card {
    background: var(--surface-color);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
}

.about-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary-color);
}

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

.about-card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

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

/* Products Section */
.products {
    padding: 8rem 2rem;
    background: var(--surface-color);
}

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

h2 {
    font-size: 2.5rem;
    margin-bottom: 4rem;
    text-align: center;
}

.product-showcase {
    background: var(--bg-color);
    border-radius: 24px;
    padding: 3rem;
    border: 1px solid rgba(255, 255, 255, 0.05);
    text-align: center;
}

.product-header {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
    justify-content: center;
}

.product-icon {
    width: 64px;
    height: 64px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.product-name {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--text-color);
    line-height: 1;
}

.product-tag {
    display: inline-block;
    background: rgba(255, 255, 255, 0.1);
    padding: 0.2rem 0.8rem;
    border-radius: 12px;
    font-size: 0.8rem;
    color: var(--primary-color);
    font-weight: 600;
    margin-top: 0.5rem;
}

.product-desc {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.product-image-container {
    margin: 0 auto 3rem auto;
    max-width: 600px;
    /* Limit width to approx 50% of typical container */
    width: 100%;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.product-screenshot {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.5s ease;
}

.product-screenshot:hover {
    transform: scale(1.02);
}

.product-actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 3rem;
    justify-content: center;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-bottom: 3rem;
}

.feature-card {
    background: var(--surface-color);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    transition: var(--transition);
    text-align: left;
}

.feature-card:hover {
    border-color: var(--primary-color);
}

.feature-card h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Installation Section (Nested) */
.installation-guide {
    margin-top: 3rem;
    padding-top: 3rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.installation-guide h4 {
    font-size: 1.5rem;
    margin-bottom: 2rem;
}

.install-tabs {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.os-card {
    background: var(--surface-color);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid rgba(255, 255, 255, 0.05);
    text-align: left;
}

.os-card h5 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.os-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.os-card p + p {
    margin-top: 1.5rem;
}

.os-card code {
    display: block;
    background: rgba(0, 0, 0, 0.3);
    padding: 0.5rem;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.85rem;
    word-break: break-all;
    color: var(--primary-color);
}

.os-card code + p {
    margin-top: 2rem;
}

/* Footer */
.footer {
    padding: 4rem 2rem;
    text-align: center;
    color: var(--text-secondary);
    background: var(--bg-color);
}

.footer a {
    color: var(--primary-color);
    text-decoration: underline;
}

/* Responsive */
@media (max-width: 768px) {
    h1.glitch {
        font-size: 3rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .pulse-circle {
        width: 300px;
        height: 300px;
    }

    .navbar {
        grid-template-columns: 1fr auto;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 250px;
        background: var(--surface-color);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 2rem;
        transition: right 0.3s ease;
        box-shadow: -5px 0 15px rgba(0, 0, 0, 0.3);
        z-index: 100;
    }

    .nav-links.active {
        right: 0;
    }

    .nav-links a {
        font-size: 1.5rem;
    }

    .menu-btn {
        display: flex;
    }

    .product-header {
        flex-direction: column;
        gap: 0.5rem;
        align-items: center;
    }

    .feature-grid,
    .install-tabs {
        grid-template-columns: 1fr;
    }
}