/* =========================================
   1. VARIABLES & THEME SETUP
   ========================================= */
:root {
    /* Fonts */
    --font-heading: 'Manrope', sans-serif;
    --font-body: 'Inter', sans-serif;

    /* Light Mode (Default) */
    --primary: #1F2937;       /* Dark Charcoal */
    --secondary: #D97706;     /* Industrial Amber/Orange */
    --secondary-hover: #B45309;
    --accent: #64748B;        /* Steel Blue/Grey */
    --bg-body: #F3F4F6;       /* Light Grey / Off-white */
    --bg-card: #FFFFFF;
    --text-main: #111827;
    --text-muted: #4B5563;
    --border: #E5E7EB;
    --shadow: 0 4px 20px -2px rgba(0, 0, 0, 0.1);
    --glass: rgba(255, 255, 255, 0.8);
    
    /* Spacing & Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --container: 1280px;
    --header-height: 80px;
}

/* Dark Mode Variables */
[data-theme="dark"] {
    --bg-body: #111827;       /* Deep Graphite */
    --bg-card: #1F2937;       /* Lighter Charcoal */
    --text-main: #F9FAFB;
    --text-muted: #9CA3AF;
    --border: #374151;
    --shadow: 0 4px 20px -2px rgba(0, 0, 0, 0.5);
    --glass: rgba(17, 24, 39, 0.8);
}

/* =========================================
   2. GLOBAL RESET & TYPOGRAPHY
   ========================================= */
* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    font-family: var(--font-body);
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--text-main);
}

a { text-decoration: none; color: inherit; transition: 0.3s ease; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 20px;
}

/* =========================================
   3. COMPONENTS & UI ELEMENTS
   ========================================= */

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    border: none;
}

.btn-primary {
    background: var(--secondary);
    color: #fff;
    box-shadow: 0 4px 14px rgba(217, 119, 6, 0.4);
}

.btn-primary:hover {
    background: var(--secondary-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(217, 119, 6, 0.6);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

[data-theme="dark"] .btn-outline {
    border-color: #fff;
    color: #fff;
}

.btn-outline:hover {
    background: var(--primary);
    color: #fff;
}

/* Cards */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 2rem;
    transition: transform 0.4s ease, box-shadow 0.4s ease;
    position: relative;
    overflow: hidden;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow);
    border-color: var(--secondary);
}

/* Section Headings */
.section-title {
    text-align: center;
    margin-bottom: 3rem;
    position: relative;
}

.section-title span {
    color: var(--secondary);
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 0.9rem;
    font-weight: 700;
}

.section-title h2 {
    font-size: 2.5rem;
    margin-top: 0.5rem;
}

/* =========================================
   4. HEADER & NAVIGATION
   ========================================= */
header {
    height: var(--header-height);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: var(--glass);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: all 0.3s ease;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--primary);
    display: flex;
    align-items: center;
    gap: 8px;
}

[data-theme="dark"] .logo { color: #fff; }
.logo span { color: var(--secondary); }

.nav-links { display: flex; gap: 30px; }

.nav-links a {
    font-weight: 500;
    font-size: 1rem;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -4px;
    left: 0;
    background-color: var(--secondary);
    transition: width 0.3s ease;
}

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

/* Theme Toggle */
.theme-toggle {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1.2rem;
    color: var(--text-main);
    padding: 8px;
    transition: transform 0.3s ease;
}
.theme-toggle:hover { transform: rotate(15deg); }

/* Hamburger */
.hamburger { display: none; cursor: pointer; }

/* =========================================
   5. MOBILE STICKY BAR
   ========================================= */
.mobile-sticky-bar {
    display: none; /* Visible only on mobile */
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    z-index: 999;
    padding: 10px 20px;
    box-shadow: 0 -4px 10px rgba(0,0,0,0.1);
}

.mobile-sticky-bar .grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
}

/* =========================================
   6. ANIMATIONS
   ========================================= */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-up.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Floating WhatsApp */
.whatsapp-float {
    position: fixed;
    bottom: 90px; /* Above sticky bar on mobile */
    right: 20px;
    background: #25D366;
    color: white;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 2rem;
    box-shadow: 0 4px 10px rgba(0,0,0,0.3);
    z-index: 998;
    transition: transform 0.3s ease;
}

.whatsapp-float:hover { transform: scale(1.1); }

/* =========================================
   7. RESPONSIVE DESIGN
   ========================================= */
@media (max-width: 768px) {
    .nav-links {
        position: fixed;
        top: var(--header-height);
        right: -100%;
        width: 80%;
        height: calc(100vh - var(--header-height));
        background: var(--bg-card);
        flex-direction: column;
        padding: 2rem;
        transition: 0.4s ease;
        border-left: 1px solid var(--border);
    }

    .nav-links.active { right: 0; }
    .hamburger { display: block; font-size: 1.5rem; }
    
    .mobile-sticky-bar { display: block; }
    body { padding-bottom: 70px; } /* Space for sticky bar */
    
    .section-title h2 { font-size: 2rem; }
    .whatsapp-float { bottom: 80px; width: 50px; height: 50px; font-size: 1.5rem; }
}