:root {
    /* Light Mode - Warm & Organic */
    --bg-color: #fdfbf7; /* Warm rice paper white */
    --text-color: #2c2a29; /* Soft charcoal */
    --header-bg: rgba(253, 251, 247, 0.85);
    --accent-color: #a1887f; /* Muted clay */
    --card-bg: #ffffff;
    --card-border: transparent;
    --shadow-color: rgba(44, 42, 41, 0.08);
    --hero-overlay: linear-gradient(rgba(0,0,0,0.3), rgba(0,0,0,0.6));
    --font-serif: 'Nanum Myeongjo', serif;
    --font-sans: 'Noto Sans KR', sans-serif;
}

[data-theme="dark"] {
    /* Dark Mode - Deep & Elegant */
    --bg-color: #1a1a1a;
    --text-color: #e6e6e6;
    --header-bg: rgba(26, 26, 26, 0.85);
    --accent-color: #d7ccc8; /* Pale ceramic */
    --card-bg: #262626;
    --card-border: transparent;
    --shadow-color: rgba(0, 0, 0, 0.4);
    --hero-overlay: linear-gradient(rgba(0,0,0,0.5), rgba(0,0,0,0.8));
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-color);
    color: var(--text-color);
    margin: 0;
    line-height: 1.6;
    transition: background-color 0.4s ease, color 0.4s ease;
}

/* Glassmorphism Sticky Header */
header {
    background-color: var(--header-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 1.5rem 2rem;
    position: sticky;
    top: 0;
    z-index: 1000;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(0,0,0,0.05);
    transition: background-color 0.4s ease;
}

h1 {
    font-family: var(--font-serif);
    font-size: 1.8rem;
    font-weight: 700;
    margin: 0;
    letter-spacing: -0.02em;
}

/* Navigation */
nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    gap: 2rem;
}

nav a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    font-size: 0.95rem;
    position: relative;
    transition: color 0.3s ease;
}

nav a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 1px;
    bottom: -4px;
    left: 0;
    background-color: var(--accent-color);
    transition: width 0.3s ease;
}

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

nav a:hover::after {
    width: 100%;
}

/* Controls (Clock & Theme) */
.header-controls {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.language-selector {
    display: flex;
    gap: 0.2rem;
    background: rgba(0,0,0,0.05);
    padding: 0.2rem;
    border-radius: 20px;
}

[data-theme="dark"] .language-selector {
    background: rgba(255,255,255,0.1);
}

.lang-btn {
    background: transparent;
    border: none;
    color: var(--text-color);
    padding: 0.3rem 0.6rem;
    cursor: pointer;
    border-radius: 15px;
    font-size: 0.7rem;
    font-weight: 700;
    transition: all 0.3s ease;
    opacity: 0.5;
}

.lang-btn:hover {
    opacity: 0.8;
}

.lang-btn.active {
    background-color: var(--card-bg);
    box-shadow: 0 2px 8px var(--shadow-color);
    opacity: 1;
}

.clock {
    font-family: var(--font-sans);
    font-size: 0.85rem;
    opacity: 0.8;
    font-variant-numeric: tabular-nums;
}

.theme-toggle button {
    background: transparent;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 0.4rem 0.8rem;
    cursor: pointer;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.3s ease;
}

.theme-toggle button:hover {
    background-color: var(--text-color);
    color: var(--bg-color);
    transform: translateY(-1px);
}

/* Hero Section */
.hero {
    height: 70vh;
    min-height: 500px;
    background-image: var(--hero-overlay), url('https://images.unsplash.com/photo-1578973625969-8e12d4d124d7?q=80&w=1974&auto=format&fit=crop');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #fff;
    padding: 0 1rem;
}

.hero h2 {
    font-family: var(--font-serif);
    font-size: 3.5rem;
    margin: 0 0 1rem 0;
    font-weight: 400;
    text-shadow: 0 4px 12px rgba(0,0,0,0.3);
    animation: fadeInUp 1s ease-out;
}

.hero p {
    font-size: 1.2rem;
    font-weight: 300;
    opacity: 0.9;
    max-width: 600px;
    margin: 0;
    animation: fadeInUp 1s ease-out 0.2s backwards;
}

/* Products Section */
.products {
    padding: 5rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.products h2 {
    font-family: var(--font-serif);
    font-size: 2rem;
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
    display: inline-block;
    left: 50%;
    transform: translateX(-50%);
}

.products h2::after {
    content: '';
    display: block;
    width: 40px;
    height: 1px;
    background-color: var(--accent-color);
    margin: 1rem auto 0;
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
}

/* Footer */
footer {
    background-color: var(--bg-color);
    text-align: center;
    padding: 3rem 0;
    border-top: 1px solid rgba(0,0,0,0.05);
    opacity: 0.7;
    font-size: 0.9rem;
}

/* Keyframes */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Responsive */
@media (max-width: 768px) {
    header {
        flex-direction: column;
        gap: 1rem;
        padding: 1rem;
    }
    
    .header-controls {
        width: 100%;
        justify-content: space-between;
    }

    nav ul {
        gap: 1rem;
    }
    
    .hero h2 {
        font-size: 2.5rem;
    }
}