:root {
    /* Premium Tinted Palette - Cool/Blue leaning per TekLot's primary Blue */
    --brand-hue: 220; /* Blue-ish */
    
    /* Backgrounds: Off-white with a subtle blue tint (The "Expensive" look) */
    --tk-bg: hsl(var(--brand-hue), 25%, 98%);
    --tk-surface: #ffffff;
    
    /* Neutrals: Injected with brand hue instead of pure grey */
    --tk-text-main: hsl(var(--brand-hue), 40%, 12%);   /* Near-black with blue shift */
    --tk-text-muted: hsl(var(--brand-hue), 15%, 45%); /* Muted slate blue */
    --tk-border: hsl(var(--brand-hue), 20%, 90%);     /* Subtle tinted border */
    
    /* Accents */
    --tk-primary: #0d6efd;
    --tk-primary-soft: hsl(var(--brand-hue), 90%, 96%); /* Hue-accurate subtle tint */
}

body {
    padding-top: 80px;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    color: var(--tk-text-main);
    background-color: var(--tk-bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

/* Glass Navbar with Tinted Border */
.navbar {
    background: rgba(255, 255, 255, 0.8) !important;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--tk-border);
    padding: 0.8rem 0;
    box-shadow: 0 1px 0 0 rgba(255, 255, 255, 0.5) inset;
}

.navbar-brand {
    font-weight: 700;
    letter-spacing: -0.02em;
    display: flex;
    align-items: center;
    padding-left: 0;
    margin-left: 0;
}

.nav-link {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--tk-text-muted) !important;
    padding: 0.5rem 1.8rem !important;
    transition: all 0.2s ease;
}

.nav-link:hover {
    color: var(--tk-primary) !important;
}

.nav-link.active {
    color: var(--tk-primary) !important;
}

.nav-item:last-child .nav-link {
    padding-right: 0 !important;
}

/* Main Content Area */
.main-content {
    padding: 2rem 1.25rem;
    min-height: 80vh;
}

@media (min-width: 992px) {
    .main-content { padding: 2rem 0; }
}

/* Premium Typography & Headings */
h1, h2, h3, h4 { 
    font-weight: 800; 
    color: var(--tk-text-main);
    letter-spacing: -0.03em;
}

h1 { margin-bottom: 1.25rem; }

/* Expertise Sections (Simple Style) */
details {
    background: transparent;
    border: none;
    margin-bottom: 0.5rem;
}

summary {
    padding: 0.5rem 0;
    cursor: pointer;
    outline: none;
    list-style: none;
}

summary h3 {
    font-size: 1.25rem;
    margin: 0;
    display: flex;
    align-items: center;
}

summary i {
    color: var(--tk-primary);
    margin-right: 0.75rem;
}

/* Content inside Details */
.ps-4 {
    padding-left: 2.1rem !important; /* Adjusted for smaller icon margin */
    padding-bottom: 1rem;
    color: var(--tk-text-muted);
}

/* Horizontal Rules */
hr { 
    border-top: 1px solid hsl(var(--brand-hue), 20%, 85%); /* Slightly darker than border */
    margin: 1.5rem 0; 
    opacity: 1; /* Full opacity for better contrast */
}

/* Footer (Tinted Neutral) */
footer {
    background: var(--tk-primary-soft);
    padding: 4rem 0;
    margin-top: 5rem;
    border-top: 1px solid var(--tk-border);
}

footer .mb-1 {
    font-weight: 600;
    color: var(--tk-text-main);
}

footer .small {
    color: var(--tk-text-muted);
    letter-spacing: 0.05em;
}