:root {
    --bg-color: #0a0b0f;
    --bg-alt: #0f1017;
    --bg-footer: #080909;
    --text-primary: #e8eaf0;
    --text-secondary: #a0a8c0;
    --text-tertiary: #b0b8d0;
    --text-muted: #8090b0;
    --text-footer: #404560;
    --accent-gradient: linear-gradient(135deg, #00d4ff, #7c3aed);
    --card-bg: #13141d;
    --max-width: 1100px;
    --font-heading: 'Space Grotesk', sans-serif;
    --font-body: 'Inter', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

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

h1, h2, h3, .brand, .nav-links a {
    font-family: var(--font-heading);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
}

/* Header & Nav */
header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(13, 14, 20, 0.92);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.07);
}

header nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
}

.brand {
    font-size: 1.5rem;
    font-weight: 700;
    text-decoration: none;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

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

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

.nav-links a:hover {
    color: white;
}

/* Hero Section */
#hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 4rem 2rem;
    background: radial-gradient(circle at center, rgba(124, 58, 237, 0.15), transparent 70%);
}

#hero h1 {
    font-size: clamp(3rem, 8vw, 6rem);
    font-weight: 700;
    line-height: 1.1;
    letter-spacing: -0.02em;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1.5rem;
}

.hero-sub {
    font-size: clamp(1rem, 2.5vw, 1.25rem);
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
    line-height: 1.7;
}

.btn-primary {
    display: inline-block;
    margin-top: 2.5rem;
    padding: 0.9rem 2.5rem;
    background: var(--accent-gradient);
    color: white;
    text-decoration: none;
    font-weight: 600;
    border-radius: 6px;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    opacity: 0.85;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0, 212, 255, 0.3);
}

/* About Section */
#about {
    background-color: var(--bg-alt);
    padding: 6rem 0;
}

#about h2 {
    font-size: 2.25rem;
    font-weight: 700;
    color: white;
    margin-bottom: 1.5rem;
}

#about p {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-tertiary);
    max-width: 720px;
}

/* Principles Section */
#principles {
    padding: 6rem 0;
}

#principles h2 {
    font-size: 2.25rem;
    font-weight: 700;
    color: white;
    margin-bottom: 2.5rem;
}

.principles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
}

.card {
    background: var(--card-bg);
    border: 1px solid rgba(255, 255, 255, 0.08);
    border-radius: 12px;
    padding: 2rem 1.5rem;
    transition: all 0.25s ease;
}

.card:hover {
    border-color: rgba(0, 212, 255, 0.3);
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Contact Section */
#contact {
    background-color: var(--bg-alt);
    padding: 6rem 0;
    text-align: center;
}

#contact h2 {
    font-size: 2.25rem;
    font-weight: 700;
    color: white;
    margin-bottom: 1rem;
}

#contact p {
    color: var(--text-secondary);
}

.contact-links {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 2rem;
}

.contact-link {
    color: #00d4ff;
    font-size: 1.1rem;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.contact-link:hover {
    color: white;
    text-decoration: underline;
}

/* Footer */
footer {
    background-color: var(--bg-footer);
    padding: 2rem;
    text-align: center;
    color: var(--text-footer);
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 768px) {
    header nav {
        flex-direction: column;
        gap: 1rem;
        padding: 1rem;
    }

    .nav-links {
        gap: 1rem;
    }

    .nav-links a {
        font-size: 0.85rem;
    }

    .contact-links {
        flex-direction: column;
        align-items: center;
        gap: 1rem;
    }
}