:root {
    --bg-black: #000000;
    --bg-dark-blue: #0a1070;
    --primary-blue: #2451d1;
    --light-gray: #fcfcfc;
    --text-white: #ffffff;
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Vazirmatn', sans-serif;
}

body {
    background-color: var(--bg-black);
    color: var(--text-white);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Header & Nav */
header {
    background: rgba(10, 16, 112, 0.8);
    backdrop-filter: blur(10px);
    padding: 1rem 5%;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--primary-blue);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 1.5rem;
}

.logo img {
    height: 50px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 20px;
}

.nav-links a {
    text-decoration: none;
    color: var(--light-gray);
    font-size: 0.9rem;
    transition: var(--transition);
}

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

.btn-login {
    background: var(--primary-blue);
    padding: 8px 15px;
    border-radius: 5px;
}

/* Hero Section */
.hero {
    height: 1000vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: radial-gradient(circle at center, var(--bg-dark-blue) 0%, var(--bg-black) 70%);
    padding: 0 10%;
}

.hero-logo-large img {
    width: 150px;
    margin-bottom: 20px;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
}

.accent-text {
    color: var(--primary-blue);
    text-shadow: 0 0 15px var(--primary-blue);
}

.cta-button {
    display: inline-block;
    margin-top: 30px;
    padding: 12px 30px;
    background: var(--primary-blue);
    color: white;
    text-decoration: none;
    border-radius: 30px;
    font-weight: bold;
    transition: var(--transition);
}

.cta-button:hover {
    transform: scale(1.05);
    box-shadow: 0 0 20px var(--primary-blue);
}

/* Billboard Section */
.billboard-section {
    padding: 100px 10%;
    background: var(--bg-black);
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
    font-size: 2rem;
    border-bottom: 2px solid var(--bg-dark-blue);
    display: inline-block;
    width: 100%;
}

.announcement-container {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 30px;
}

.news-card {
    background: var(--bg-dark-blue);
    padding: 25px;
    border-radius: 15px;
    border-left: 5px solid var(--primary-blue);
    transition: var(--transition);
}

.news-card:hover {
    transform: translateX(-10px);
}

.cat-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

.cat-item {
    background: #111;
    padding: 15px;
    text-align: center;
    border-radius: 10px;
    border: 1px solid var(--bg-dark-blue);
    cursor: pointer;
    transition: var(--transition);
}

.cat-item:hover {
    background: var(--primary-blue);
}

/* Footer */
footer {
    background: var(--bg-dark-blue);
    padding: 40px 10%;
    text-align: center;
    border-top: 1px solid var(--primary-blue);
}

.footer-logo {
    height: 50px;
    margin-bottom: 15px;
}

.contact-id span {
    color: var(--primary-blue);
    font-weight: bold;
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .nav-links {
        display: none; /* در ادامه نیاز به منوی همبرگری داریم */
    }
    .announcement-container {
        grid-template-columns: 1fr;
    }
    .hero h1 {
        font-size: 2rem;
    }
}