:root {
    --primary-color: #007bff;
    --primary-gradient: linear-gradient(135deg, #007bff 0%, #00d4ff 100%);
    --dark-bg: #0f172a;
    --dark-card: #1e293b;
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --transition-smooth: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Inter', sans-serif;
    color: #334155;
    background-color: #f8fafc;
    overflow-x: hidden;
}

/* --- Preloader --- */
#preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--dark-bg);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.loader {
    width: 50px;
    height: 50px;
    border: 5px solid #1e293b;
    border-top: 5px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* --- Typography Helpers --- */
.text-gradient {
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.max-w-700 { max-width: 700px; }
.section-padding { padding: 100px 0; }
.mb-6 { margin-bottom: 4rem; }

/* --- Navbar --- */
.navbar {
    transition: var(--transition-smooth);
    padding: 20px 0;
}

.navbar.scrolled {
    background: rgba(15, 23, 42, 0.95);
    backdrop-filter: blur(10px);
    padding: 12px 0;
    border-bottom: 1px solid var(--glass-border);
}

.nav-link {
    font-weight: 500;
    margin: 0 10px;
    color: #cbd5e1 !important;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition-smooth);
}

.nav-link:hover::after, .nav-link.active::after {
    width: 100%;
}

/* --- Hero Section --- */
.hero-section {
    min-height: 100vh;
    background: var(--dark-bg);
    position: relative;
    padding-top: 100px;
    z-index: 1;
}

.hero-section .overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 70% 30%, rgba(0, 123, 255, 0.15) 0%, transparent 50%);
    pointer-events: none;
}

.hero-image-wrapper {
    position: relative;
    transform: perspective(1000px) rotateY(-10deg);
    transition: var(--transition-smooth);
}

.hero-image-wrapper:hover {
    transform: perspective(1000px) rotateY(0deg);
}

.shadow-2xl {
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

/* --- Cards --- */
.project-card {
    border-radius: 20px;
    transition: var(--transition-smooth);
    overflow: hidden;
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08) !important;
}

.icon-box {
    width: 60px;
    height: 60px;
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
}

.feature-list {
    padding-left: 0;
    list-style: none;
}

.feature-list li {
    margin-bottom: 10px;
    display: flex;
    align-items: center;
}

.bg-primary-soft { background-color: rgba(0, 123, 255, 0.1); }
.bg-warning-soft { background-color: rgba(255, 193, 7, 0.1); }
.bg-dark-soft { background-color: rgba(30, 41, 59, 0.05); }

.divider {
    width: 60px;
    height: 4px;
    background: var(--primary-color);
    border-radius: 2px;
}

/* --- Advanced Cards (Glassmorphism) --- */
.bg-glass {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    transition: var(--transition-smooth);
}

.advanced-card:hover {
    border-color: var(--primary-color) !important;
    background: rgba(255, 255, 255, 0.1);
}

.container-custom {
    max-width: 1200px;
}

/* --- Capstone Section --- */
.capstone-section {
    background: #fff;
    overflow: hidden;
}

.capstone-wrapper {
    background: #fff;
    border: 1px solid #f1f5f9;
}

.background-elements .blob {
    position: absolute;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    filter: blur(80px);
    z-index: 0;
    opacity: 0.15;
}

.blob-1 { top: -100px; left: -100px; background: var(--primary-color); }
.blob-2 { bottom: -100px; right: -100px; background: #ec4899; }

/* --- Footer --- */
footer .social-links a {
    transition: var(--transition-smooth);
}

footer .social-links a:hover {
    color: var(--primary-color) !important;
    transform: scale(1.2);
}

/* --- Animations --- */
[data-aos] {
    pointer-events: none;
}

.aos-animate {
    pointer-events: auto;
}

@media (max-width: 768px) {
    .display-3 { font-size: 2.8rem; }
    .section-padding { padding: 60px 0; }
}