/* KEYFRAMES FOR ANIMATION */
@keyframes border-flicker {
    0%, 100% { border-color: rgba(52, 211, 153, 0.5); }
    50% { border-color: rgba(16, 185, 129, 0.8); }
}

/* BASE STYLES */
body {
    font-family: 'Roboto', sans-serif;
    /* Deeper, more atmospheric background */
    background: linear-gradient(135deg, #0d121c, #03070b); 
    color: #e2e8f0; 
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}
main {
    flex-grow: 1;
}

/* 1. TOP NAVIGATION BUTTONS (Sharper, more geometric) */
.nav-btn {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    transition: all 0.3s;
    color: #fff;
    border-bottom: 2px solid transparent;
    background: none; 
    border-radius: 0; /* Removing rounded edges for a sharper look */
    position: relative;
    /* Ensure buttons don't shrink too much on mobile */
    flex-shrink: 0; 
}
.nav-btn::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 80%;
    height: 2px;
    background-color: #10b981;
    transition: transform 0.3s ease-in-out;
}
.nav-btn:hover::after {
    transform: translateX(-50%) scaleX(1);
}
.nav-btn.active {
    color: #34d399;
    font-weight: 700;
    text-shadow: 0 0 8px rgba(52, 211, 153, 0.7); /* Subtle text glow */
}
.nav-btn.active::after {
    transform: translateX(-50%) scaleX(1);
    background-color: #34d399;
    height: 3px;
    box-shadow: 0 0 10px rgba(52, 211, 153, 1);
}

/* Generator Button (Amber - different active state) */
.generator-btn.active {
    color: #fcd34d;
    text-shadow: 0 0 8px rgba(252, 211, 77, 0.7);
}

/* Sub Navigation Buttons */
.sub-nav-btn {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    font-weight: 500;
    transition: color 0.2s, background 0.2s, border-color 0.2s, transform 0.2s; 
    border-radius: 0.5rem;
    color: #d1d5db;
    border: 1px solid #374151;
    background-color: rgba(55, 65, 81, 0.3);
}
.sub-nav-btn:hover {
    background-color: rgba(75, 85, 99, 0.5);
    color: #fff;
    transform: scale(1.05); /* Slight pop on hover */
}
.sub-nav-btn.active {
    background-color: rgba(16, 185, 129, 0.7); 
    color: white; 
    border-color: #4ade80; 
    font-weight: 700; 
    box-shadow: 0 0 15px rgba(16, 185, 129, 0.6);
    transform: scale(1.05); /* Slight pop when active */
}
/* END: Sub Navigation Buttons */

/* Futuristic Card Styling */
.futuristic-card {
    /* Glass-morphism effect on backdrop */
    background-color: rgba(17, 24, 39, 0.7);
    backdrop-filter: blur(12px);
    padding: 1.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 10px 25px rgba(0,0,0,0.5), 0 0 40px rgba(52, 211, 153, 0.05);
    /* Animated Border */
    border: 2px solid;
    animation: border-flicker 4s infinite alternate; 
    transition: all 0.5s ease-in-out;
}
.futuristic-card:hover {
    box-shadow: 0 0 40px rgba(52, 211, 153, 0.5); /* Stronger hover glow */
}
/* END: Futuristic Card Styling */

.content-image {
    border-radius: 0.75rem;
    box-shadow: 0 10px 25px rgba(0,0,0,0.5), 0 0 40px rgba(52, 211, 153, 0.05);
    width: 100%;
    object-fit: cover;
    aspect-ratio: 16/9;
    border: 2px solid #22c55e;
    transition: transform 0.5s;
}
.content-image:hover {
    box-shadow: 0 0 35px rgba(16, 185, 129, 0.8);
    transform: scale(1.02) rotateZ(0.5deg);
}

/* 4. HEADER (Glass-morphism) */
.header-nav {
    background: rgba(13, 17, 23, 0.7); /* Reduced opacity for transparency */
    backdrop-filter: blur(10px) saturate(180%);
    -webkit-backdrop-filter: blur(10px) saturate(180%);
    border-bottom: 2px solid rgba(52, 211, 153, 0.4);
}

/* Footer Custom Style */
.futuristic-footer {
    background-color: rgba(17, 24, 39, 0.8); 
    backdrop-filter: blur(6px); 
    padding: 1.5rem 0; 
    margin-top: 3rem; 
    border-top: 2px solid rgba(16, 185, 129, 0.25); 
}

/* Custom scrollbar for clean navigation on small screens */
#main-nav {
    -webkit-overflow-scrolling: touch;
    overflow-x: auto;
}

#main-nav::-webkit-scrollbar {
    height: 6px;
}
#main-nav::-webkit-scrollbar-track {
    background: transparent;
}
#main-nav::-webkit-scrollbar-thumb {
    background-color: #4ade80;
    border-radius: 3px;
    border: 1px solid #10b981;
}