/* --- CSS Global Variables & Theme Management --- */
:root {
    --primary-color: #00d2ff;
    --font-main: 'Inter', sans-serif;
    --bg-body: #050a14;
    --bg-nav: #050a14;
    --text-main: #ffffff;
    --text-secondary: #94a3b8;
    --card-bg: #101a2d;
    --card-border: rgba(255, 255, 255, 0.05);
    --shadow-nav: 0 4px 15px rgba(0,0,0,0.4);
}

body.light-mode {
    --bg-body: #f8fafc;
    --bg-nav: #f8fafc;
    --text-main: #101a2d;
    --text-secondary: #64748b;
    --card-bg: #ffffff;
    --card-border: rgba(0, 0, 0, 0.1);
    --shadow-nav: 0 4px 15px rgba(0,0,0,0.05);
}

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

body {
    font-family: var(--font-main);
    background-color: var(--bg-body);
    color: var(--text-main);
    transition: background-color 0.3s ease, color 0.3s ease;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

/* --- Navbar --- */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 10%;
    background-color: var(--bg-nav);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--card-border);
    transition: background-color 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.logo {
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--primary-color);
    letter-spacing: -1px;
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 25px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 25px;
}

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

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

.theme-toggle {
    cursor: pointer;
    font-size: 1.1rem;
    color: var(--text-main);
    transition: color 0.3s ease, transform 0.2s ease;
    display: flex;
    align-items: center;
    padding: 5px;
}

.theme-toggle:hover {
    color: var(--primary-color);
    transform: scale(1.1);
}

/* --- Hero Section --- */
.hero {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 38px 10%;
    min-height: 85vh;
    background: radial-gradient(circle at center, rgba(0, 210, 255, 0.05) 0%, rgba(5, 10, 20, 0) 70%);
}

.hero-logo {
    margin-bottom: 20px;
}

.hero-logo img {
    width: 140px;
    height: auto;
    filter: drop-shadow(0 0 15px rgba(0, 210, 255, 0.3));
}

body.light-mode .hero {
    background: radial-gradient(circle at center, rgba(0, 210, 255, 0.1) 0%, rgba(248, 250, 252, 0) 70%);
}

.hero h1 {
    font-size: 4rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 25px;
    letter-spacing: -2.5px;
}

.hero h1 span {
    color: var(--primary-color);
}

.hero p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    max-width: 700px;
    margin-bottom: 40px;
    font-weight: 300;
    line-height: 1.6;
}

.btn-cta {
    background-color: var(--primary-color);
    color: #050a14;
    padding: 16px 40px;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 12px;
    transition: 0.3s ease, box-shadow 0.3s ease;
}

.btn-cta:hover {
    box-shadow: 0 10px 30px rgba(0, 210, 255, 0.4);
    transform: translateY(-2px);
}

.version-info {
    margin-top: 25px;
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 400;
    letter-spacing: 0.5px;
}

.version-tag {
    color: var(--primary-color);
    font-weight: 600;
}

/* --- Features Section --- */
.features {
    padding: 100px 10%;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card {
    background-color: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 40px;
    transition: 0.3s ease, border-color 0.3s ease, transform 0.3s ease;
}

.feature-card:hover {
    border-color: rgba(0, 210, 255, 0.2);
    transform: translateY(-8px);
}

.feature-card i {
    font-size: 2.2rem;
    color: var(--primary-color);
    margin-bottom: 25px;
    display: inline-block;
}

.feature-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--text-main);
}

.feature-card p {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 300;
    line-height: 1.6;
}

/* --- Footer --- */
footer {
    text-align: center;
    padding: 60px 10%;
    border-top: 1px solid var(--card-border);
    color: var(--text-secondary);
    font-size: 0.9rem;
}

footer p {
    margin-bottom: 10px;
}

/* --- Mobile Responsive --- */
@media (max-width: 768px) {
    .hero-logo img { width: 60px; }
    nav { padding: 15px 5%; }
    .nav-right, .nav-links { gap: 15px; }
    .nav-links a { font-size: 0.85rem; }
    .hero { padding: 100px 5%; }
    .hero h1 { font-size: 2.8rem; letter-spacing: -1.5px; }
    .hero p { font-size: 1rem; }
    .features { padding: 60px 5%; gap: 20px; }
    .feature-card { padding: 30px; }
}