:root {
    --primary-color: #0b1120;
    --accent-color: #3b82f6; /* Modern Blue */
    --accent-hover: #2563eb;
    --text-color: #f8fafc;
    --card-bg: rgba(15, 23, 42, 0.6);
    --glass-border: rgba(255, 255, 255, 0.1);
}

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

body {
    background-color: var(--primary-color);
    color: var(--text-color);
    overflow-x: hidden;
}

/* Dynamic Background Slider */
#bg-slider {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: -2;
    background-color: #000;
}

.slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0;
    transition: opacity 1.5s ease-in-out;
}

.slide.active {
    opacity: 0.6; /* Keeps the overlay dark enough for text readability */
}

/* Dark Gradient Overlay for optimal readability */
.overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: linear-gradient(to bottom, rgba(0,0,0,0.8) 0%, rgba(0,0,0,0.3) 50%, rgba(0,0,0,0.9) 100%);
    z-index: -1;
}

/* Navbar */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 24px 5%;
    background: rgba(0,0,0,0.3);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--glass-border);
}

.logo {
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: 1px;
    background: linear-gradient(to right, #60a5fa, #a78bfa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-links a {
    color: white;
    text-decoration: none;
    margin-left: 32px;
    font-weight: 500;
    transition: color 0.3s;
}

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

.btn {
    padding: 10px 24px;
    border-radius: 8px;
    background: var(--accent-color);
    color: white;
    text-decoration: none;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all 0.3s;
}
.btn:hover {
    background: var(--accent-hover);
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4);
}

/* Hero Section */
header.hero {
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 0 20px;
}

.hero h1 {
    font-size: 4rem;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    max-width: 900px;
}

.hero p {
    font-size: 1.25rem;
    color: #cbd5e1;
    max-width: 700px;
    margin-bottom: 40px;
}

/* Products Section */
.products-section {
    padding: 100px 5%;
    text-align: center;
    background: linear-gradient(to bottom, transparent, var(--primary-color) 20%);
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 60px;
    font-weight: 700;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(12px);
    padding: 40px 30px;
    border-radius: 16px;
    transition: transform 0.3s, box-shadow 0.3s;
    text-align: left;
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    border-color: rgba(255,255,255,0.3);
}

.icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
    display: inline-block;
}

.card h3 {
    font-size: 1.5rem;
    margin-bottom: 16px;
    color: #fff;
}

.card p {
    color: #94a3b8;
    line-height: 1.6;
    margin-bottom: 24px;
}

/* Modal Form */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.8);
    backdrop-filter: blur(8px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
}

.modal-overlay.open {
    opacity: 1;
    pointer-events: auto;
}

.modal-content {
    background: #0f172a;
    padding: 40px;
    border-radius: 16px;
    border: 1px solid var(--glass-border);
    max-width: 450px;
    width: 90%;
    position: relative;
    box-shadow: 0 25px 50px rgba(0,0,0,0.5);
}

.close-btn {
    position: absolute;
    top: 15px;
    right: 20px;
    font-size: 1.5rem;
    cursor: pointer;
    color: #94a3b8;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #cbd5e1;
    font-size: 0.9rem;
}

.form-control {
    width: 100%;
    padding: 12px;
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--glass-border);
    border-radius: 8px;
    color: #fff;
    font-size: 1rem;
}

.form-control:focus {
    outline: none;
    border-color: var(--accent-color);
}

.alert-message {
    padding: 12px;
    border-radius: 8px;
    margin-bottom: 20px;
    display: none;
    font-size: 0.875rem;
}

/* Auth Tabs */
.auth-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
    border-bottom: 1px solid var(--glass-border);
    padding-bottom: 8px;
}

.auth-tab {
    background: none;
    border: none;
    color: #94a3b8;
    padding: 8px 16px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    border-radius: 6px;
    transition: all 0.2s;
}

.auth-tab.active {
    color: var(--accent-color);
    background: rgba(59, 130, 246, 0.1);
}

.auth-panel {
    display: none;
}

.auth-panel.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

/* Social Buttons Grid */
.social-login-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    margin-bottom: 20px;
}

.btn-social {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    border-radius: 8px;
    color: #fff;
    font-size: 0.8rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-social:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.3);
    transform: translateY(-1px);
}

/* Auth Divider */
.auth-divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: 20px 0;
    color: #64748b;
    font-size: 0.75rem;
}

.auth-divider::before,
.auth-divider::after {
    content: '';
    flex: 1;
    border-bottom: 1px solid var(--glass-border);
}

.auth-divider span {
    padding: 0 10px;
}

.forgot-link {
    color: var(--accent-color);
    font-size: 0.8rem;
    text-decoration: none;
    transition: color 0.2s;
}

.forgot-link:hover {
    color: var(--accent-hover);
    text-decoration: underline;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}