/* CSS Variables for Dark, Techy Theme */
:root {
    --primary-accent: #00f5c8; /* A vibrant, futuristic cyan */
    --background-dark: #121212;
    --surface-dark: #1e1e1e;
    --text-light: #e0e0e0;
    --text-muted: #888888;
    --white-color: #ffffff;
    --font-family: 'Roboto', sans-serif;
    --section-padding: 80px 0;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family);
    line-height: 1.7;
    color: var(--text-light);
    background-color: var(--background-dark);
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 20px;
}

h1, h2, h3 {
    font-weight: 700;
    color: var(--white-color);
}

h2 {
    font-size: 2.8rem;
    text-align: center;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 1.5px;
}

.section-intro {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 50px auto;
    color: var(--text-muted);
}

section {
    padding: var(--section-padding);
}

/* Header */
.header {
    background: rgba(18, 18, 18, 0.8);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
    position: sticky;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
}

.logo {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--primary-accent);
    text-decoration: none;
    letter-spacing: 1px;
}

.nav-menu ul {
    list-style: none;
    display: flex;
    gap: 35px;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-light);
    font-weight: 500;
    transition: color 0.3s ease;
}

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

.hamburger { display: none; font-size: 1.5rem; cursor: pointer; }

/* Hero Section */
.hero-section {
    background: linear-gradient(rgba(18, 18, 18, 0.8), rgba(18, 18, 18, 0.8)), url('https://images.unsplash.com/photo-1554469384-e58fac16e23a?q=80&w=1932&auto=format&fit=crop') no-repeat center center/cover;
    height: 90vh;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
}

.hero-content h1 {
    font-size: 3.8rem;
    color: var(--white-color);
    margin-bottom: 15px;
    text-shadow: 0 0 10px rgba(0, 245, 200, 0.3);
}

.hero-content p {
    font-size: 1.3rem;
    color: var(--text-muted);
    margin-bottom: 35px;
    max-width: 650px;
}

.btn-cta {
    background: var(--primary-accent);
    color: var(--background-dark);
    padding: 15px 35px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    box-shadow: 0 0 20px rgba(0, 245, 200, 0.4);
}

.btn-cta:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 25px rgba(0, 245, 200, 0.6);
}

/* Card Styling (Tentang Kami & Keunggulan) */
.card, .feature-item {
    background: var(--surface-dark);
    padding: 35px;
    border-radius: 10px;
    border: 1px solid #333;
    transition: transform 0.3s ease, border-color 0.3s ease;
    text-align: center;
}

.card:hover, .feature-item:hover {
    transform: translateY(-8px);
    border-color: var(--primary-accent);
}

.card i {
    font-size: 2.5rem;
    color: var(--primary-accent);
    margin-bottom: 20px;
}

.card h3 {
    color: var(--primary-accent);
    margin-bottom: 15px;
}

.visi-misi { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 30px; }
.feature-item h3 { margin-bottom: 10px; font-size: 1.25rem; }

/* Registration Section */
.registration-section { background-color: var(--background-dark); }

.form-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 25px;
    max-width: 900px;
    margin: 0 auto;
    background: var(--surface-dark);
    padding: 40px;
    border-radius: 10px;
    border: 1px solid #333;
}

.form-group { display: flex; flex-direction: column; }
.form-group.full-width { grid-column: 1 / -1; }
.form-group label { margin-bottom: 10px; font-weight: 500; color: var(--text-muted); }

.form-group input, .form-group textarea {
    width: 100%;
    padding: 15px;
    border: 1px solid #444;
    border-radius: 5px;
    font-family: var(--font-family);
    font-size: 1rem;
    background-color: #2a2a2a;
    color: var(--text-light);
    transition: border-color 0.3s, box-shadow 0.3s;
}

.form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--primary-accent);
    box-shadow: 0 0 10px rgba(0, 245, 200, 0.3);
}

.btn-submit {
    width: 100%;
    padding: 15px;
    background: var(--primary-accent);
    color: var(--background-dark);
    border: none;
    border-radius: 5px;
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s;
}

.btn-submit:hover {
    filter: brightness(1.2);
}

/* Footer */
.footer {
    background-color: var(--surface-dark);
    color: var(--text-muted);
    padding: 50px 0 20px;
    border-top: 1px solid #333;
}

.footer-content {
    display: flex; justify-content: space-between; flex-wrap: wrap;
    gap: 30px; margin-bottom: 30px;
}

.footer-about h3, .footer-social h3 {
    color: var(--white-color);
    margin-bottom: 15px;
}

.footer-social a {
    color: var(--text-muted);
    font-size: 1.8rem;
    margin-right: 15px;
    transition: color 0.3s;
}

.footer-social a:hover { color: var(--primary-accent); }
.footer-bottom { text-align: center; padding-top: 20px; border-top: 1px solid #333; }

/* Floating WhatsApp Icon */
.whatsapp-float {
    position: fixed; bottom: 30px; right: 30px; background-color: #25D366;
    color: var(--white-color); width: 60px; height: 60px; border-radius: 50%;
    display: flex; justify-content: center; align-items: center; font-size: 2.5rem;
    box-shadow: 0 0 20px rgba(37, 211, 102, 0.5); z-index: 999;
    transition: transform 0.3s, box-shadow 0.3s;
}

.whatsapp-float:hover {
    transform: scale(1.1);
    box-shadow: 0 0 30px rgba(37, 211, 102, 0.7);
}

/* Responsive Design */
@media (max-width: 768px) {
    h2 { font-size: 2rem; }
    .hero-content h1 { font-size: 2.8rem; }
    
    .nav-menu {
        position: absolute; top: 82px; left: 0; width: 100%;
        background: var(--surface-dark); height: 0; overflow: hidden;
        transition: height 0.3s ease-in-out;
    }

    .nav-menu.active { height: 230px; }
    .nav-menu ul { flex-direction: column; align-items: center; padding: 20px 0; gap: 20px; }
    .hamburger { display: block; color: var(--white-color); }
    .form-layout { grid-template-columns: 1fr; padding: 25px; }
    .footer-content { flex-direction: column; text-align: center; }
}