/* --- CSS Variables --- */
:root {
    --primary-color: #0a192f;   /* Biru Tua Gelap */
    --secondary-color: #ffffff; /* Putih */
    --accent-color: #64ffda;    /* Hijau Aksen */
    --text-color: #8892b0;      /* Abu-abu terang untuk teks */
    --heading-color: #ccd6f6;   /* Putih kebiruan untuk heading */
    --card-bg-color: #112240;   /* Biru lebih terang untuk card */
    --font-primary: 'Inter', sans-serif;
    --font-secondary: 'Roboto', sans-serif;
}

/* --- General Styling & Resets --- */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px; /* Offset for fixed header */
}

body {
    font-family: var(--font-primary);
    background-color: var(--primary-color);
    color: var(--text-color);
    line-height: 1.6;
    font-size: 16px;
}

.container {
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
}

h1, h2, h3, h4 {
    color: var(--heading-color);
    font-family: var(--font-secondary);
    font-weight: 700;
}

p {
    margin-bottom: 1rem;
}

a {
    color: var(--accent-color);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--secondary-color);
}

.card {
    background-color: var(--card-bg-color);
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

/* --- Header & Navigation --- */
#header {
    background-color: rgba(10, 25, 47, 0.85);
    padding: 1rem 0;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    backdrop-filter: blur(10px);
    transition: top 0.3s;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-weight: bold;
    font-size: 1.5rem;
    color: var(--secondary-color);
}

.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-links a {
    color: var(--heading-color);
    font-weight: 400;
}

.burger-menu {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    background: none;
    border: none;
}

.burger-menu span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--secondary-color);
    border-radius: 3px;
    transition: all 0.3s ease-in-out;
}

/* --- Buttons --- */
.btn {
    display: inline-block;
    padding: 0.75rem 1.75rem;
    border-radius: 5px;
    font-weight: bold;
    cursor: pointer;
    text-align: center;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.btn-primary {
    background-color: var(--accent-color);
    color: var(--primary-color);
    border-color: var(--accent-color);
}

.btn-primary:hover {
    background-color: transparent;
    color: var(--accent-color);
}

.btn-secondary {
    background-color: transparent;
    color: var(--secondary-color);
    border-color: var(--secondary-color);
}

.btn-secondary:hover {
    background-color: var(--secondary-color);
    color: var(--primary-color);
}

.btn-primary-outline {
    border: 2px solid var(--accent-color);
    color: var(--accent-color);
    padding: 0.5rem 1.25rem;
}
.btn-primary-outline:hover {
    background-color: rgba(100, 255, 218, 0.1);
}


/* --- Hero Section --- */
#hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: flex-start;
    text-align: left;
    color: var(--secondary-color);
    background: url('https://images.unsplash.com/photo-1550745165-9bc0b252726a?q=80&w=2070&auto=format&fit=crop') no-repeat center center/cover;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, rgba(10, 25, 47, 0.95) 0%, rgba(10, 25, 47, 0.6) 100%);
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 700px;
}

.hero-content h1 {
    font-size: clamp(2.5rem, 5vw, 4rem);
    margin-bottom: 1rem;
}

.hero-content p {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    max-width: 550px;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
}

/* --- Content Sections --- */
.content-section {
    padding: 6rem 0;
}

.content-section:nth-child(odd) {
    background-color: var(--primary-color);
}
.content-section:nth-child(even) {
    background-color: var(--card-bg-color);
}

.content-section h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
}

.section-intro {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 3rem auto;
}

/* --- About Section (UPDATED) --- */
.subsection-title {
    text-align: center;
    font-size: 1.8rem;
    margin-top: 4rem;
    margin-bottom: 2rem;
    color: var(--heading-color);
}

.tech-focus-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 4rem;
}

.tech-card {
    background-color: var(--card-bg-color);
    padding: 2rem 1.5rem;
    border-radius: 8px;
    text-align: center;
    border: 1px solid #1d2d50;
    transition: transform 0.3s ease, border-color 0.3s ease;
}

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

.tech-icon {
    margin-bottom: 1rem;
    color: var(--accent-color);
}

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

.vision-mission {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-top: 2rem;
}

/* --- Event Section --- */
.event-list .event-item {
    margin-bottom: 1.5rem;
    border-left: 4px solid var(--accent-color);
}
.event-meta {
    font-size: 0.9rem;
    font-weight: bold;
    color: var(--accent-color);
}

/* --- Articles Section --- */
#searchInput {
    width: 100%;
    padding: 0.8rem 1rem;
    margin-bottom: 2rem;
    background-color: var(--primary-color);
    border: 1px solid var(--text-color);
    color: var(--secondary-color);
    border-radius: 5px;
    font-size: 1rem;
}
.article-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
}
.read-more {
    font-weight: bold;
}

/* --- Contact Section --- */
.contact-container {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}
.contact-form-wrapper {
    padding: 2.5rem;
}
.form-group {
    margin-bottom: 1.5rem;
}
.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    color: var(--heading-color);
}
.form-group input, .form-group textarea {
    width: 100%;
    padding: 0.8rem;
    background-color: var(--primary-color);
    border: 1px solid var(--text-color);
    color: var(--secondary-color);
    border-radius: 5px;
    font-family: var(--font-primary);
}
.contact-info h3 {
    color: var(--accent-color);
    margin-bottom: 1rem;
}
.contact-email-title {
    margin-top: 2rem;
}
.social-link {
    display: block;
    padding: 0.8rem 1rem;
    margin-bottom: 0.5rem;
    border-radius: 5px;
    text-align: center;
    font-weight: bold;
    border: 1px solid;
}
.whatsapp { border-color: #25D366; color: #25D366; }
.telegram { border-color: #0088cc; color: #0088cc; }
.whatsapp:hover { background-color: #25D366; color: white; }
.telegram:hover { background-color: #0088cc; color: white; }
.email-link {
    font-weight: bold;
    word-break: break-all;
}

/* --- Footer --- */
footer {
    background: var(--primary-color);
    padding: 4rem 0 2rem 0;
    border-top: 1px solid var(--card-bg-color);
}
.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}
.footer-content h4 {
    color: var(--accent-color);
    margin-bottom: 1rem;
}
.footer-content ul {
    list-style: none;
}
.footer-content ul li {
    margin-bottom: 0.5rem;
}
.footer-content ul a {
    color: var(--text-color);
}
.footer-copyright {
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-color);
    padding-top: 2rem;
    border-top: 1px solid var(--card-bg-color);
}

/* --- Animations --- */
.fade-in {
    animation: fadeInAnimation 1s ease-in-out forwards;
}
@keyframes fadeInAnimation {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}
.content-section {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
.content-section.visible {
    opacity: 1;
    transform: translateY(0);
}

/* --- Responsive Design --- */
@media (max-width: 768px) {
    .nav-links {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px;
        right: 0;
        background-color: var(--card-bg-color);
        width: 100%;
        padding: 2rem;
        text-align: center;
    }
    .nav-links.active {
        display: flex;
    }
    .burger-menu {
        display: flex;
    }
    .burger-menu.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    .burger-menu.active span:nth-child(2) {
        opacity: 0;
    }
    .burger-menu.active span:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }
    .vision-mission, .contact-container {
        grid-template-columns: 1fr;
    }
}