/* ========================================
   CSS Reset & Base Styles
   ======================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Brand Colors */
    --primary-color: #0066cc;
    --primary-dark: #004c99;
    --primary-light: #3385d6;
    --secondary-color: #ff6b00;
    --secondary-dark: #cc5500;
    
    /* Neutral Colors */
    --dark: #1a1a1a;
    --dark-gray: #2d2d2d;
    --gray: #666666;
    --light-gray: #f5f5f5;
    --white: #ffffff;
    
    /* Functional Colors */
    --success: #28a745;
    --warning: #ffc107;
    --danger: #dc3545;
    --info: #17a2b8;
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-weight-light: 300;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    --font-weight-extrabold: 800;
    --font-weight-black: 900;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: 16px;
    line-height: 1.6;
    color: var(--dark);
    background-color: var(--white);
    overflow-x: hidden;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-base);
}

ul {
    list-style: none;
}

button {
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
}

/* ========================================
   Container & Layout
   ======================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========================================
   Typography
   ======================================== */
.section-tag {
    display: inline-block;
    font-size: 0.875rem;
    font-weight: var(--font-weight-semibold);
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--primary-color);
    margin-bottom: var(--spacing-sm);
}

.section-title {
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    line-height: 1.2;
    color: var(--dark);
    margin-bottom: var(--spacing-md);
}

.section-description {
    font-size: 1.125rem;
    color: var(--gray);
    max-width: 700px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: 0.875rem 1.75rem;
    font-size: 1rem;
    font-weight: var(--font-weight-semibold);
    border-radius: var(--radius-md);
    transition: var(--transition-base);
    cursor: pointer;
    border: 2px solid transparent;
    white-space: nowrap;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background-color: var(--white);
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-secondary:hover {
    background-color: var(--primary-color);
    color: var(--white);
}

.btn-lg {
    padding: 1.125rem 2.25rem;
    font-size: 1.125rem;
}

/* ========================================
   Header
   ======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: var(--white);
    box-shadow: var(--shadow-md);
    transition: var(--transition-base);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md) 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--primary-color);
}

.logo-icon {
    font-size: 1.75rem;
}

.nav-list {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.nav-link {
    font-size: 0.9375rem;
    font-weight: var(--font-weight-medium);
    color: var(--dark);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition-base);
}

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

.header-btn {
    font-size: 0.9375rem;
    padding: 0.75rem 1.5rem;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: var(--spacing-xs);
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background-color: var(--dark);
    transition: var(--transition-base);
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #0066cc 0%, #004c99 100%);
    padding: 8rem 0 4rem;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%);
    pointer-events: none;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.2);
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: var(--white);
    max-width: 900px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: var(--font-weight-extrabold);
    line-height: 1.1;
    margin-bottom: var(--spacing-md);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
    font-size: 1.75rem;
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-md);
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-description {
    font-size: 1.125rem;
    line-height: 1.8;
    margin-bottom: var(--spacing-xl);
    opacity: 0.95;
}

.hero-buttons {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.hero-features {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xl);
    flex-wrap: wrap;
}

.hero-feature {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1rem;
    font-weight: var(--font-weight-medium);
}

.hero-feature i {
    color: var(--success);
}

/* ========================================
   About Section
   ======================================== */
.about {
    padding: var(--spacing-3xl) 0;
    background-color: var(--white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.about-content {
    padding-right: var(--spacing-lg);
}

.about-text {
    font-size: 1.0625rem;
    line-height: 1.8;
    color: var(--gray);
    margin-bottom: var(--spacing-md);
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
    margin: var(--spacing-xl) 0;
    padding: var(--spacing-xl) 0;
    border-top: 2px solid var(--light-gray);
    border-bottom: 2px solid var(--light-gray);
}

.stat {
    text-align: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: var(--font-weight-bold);
    color: var(--primary-color);
    margin-bottom: var(--spacing-xs);
}

.stat-label {
    font-size: 0.9375rem;
    color: var(--gray);
    font-weight: var(--font-weight-medium);
}

.about-image {
    position: relative;
}

.image-wrapper {
    position: relative;
    height: 500px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-xl);
}

.hvac-icon {
    font-size: 12rem;
    color: rgba(255, 255, 255, 0.15);
    animation: spin 20s linear infinite;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

.image-badge {
    position: absolute;
    bottom: -20px;
    right: -20px;
    background-color: var(--secondary-color);
    color: var(--white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: var(--shadow-xl);
}

.image-badge i {
    font-size: 2rem;
    display: block;
    margin-bottom: var(--spacing-xs);
}

.image-badge span {
    font-size: 0.875rem;
    font-weight: var(--font-weight-bold);
    line-height: 1.4;
    display: block;
}

/* ========================================
   Services Section
   ======================================== */
.services {
    padding: var(--spacing-3xl) 0;
    background-color: var(--light-gray);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.service-card {
    background-color: var(--white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    transition: var(--transition-base);
}

.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.service-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-light) 100%);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
}

.service-icon i {
    font-size: 2rem;
    color: var(--white);
}

.service-title {
    font-size: 1.375rem;
    font-weight: var(--font-weight-bold);
    color: var(--dark);
    margin-bottom: var(--spacing-sm);
}

.service-description {
    font-size: 0.9375rem;
    line-height: 1.7;
    color: var(--gray);
}

/* ========================================
   Why Choose Us Section
   ======================================== */
.why-choose-us {
    padding: var(--spacing-3xl) 0;
    background-color: var(--white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.feature-card {
    text-align: center;
    padding: var(--spacing-xl);
    background-color: var(--light-gray);
    border-radius: var(--radius-lg);
    transition: var(--transition-base);
}

.feature-card:hover {
    background-color: var(--white);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--secondary-dark) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-md);
}

.feature-icon i {
    font-size: 2.25rem;
    color: var(--white);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--dark);
    margin-bottom: var(--spacing-sm);
}

.feature-description {
    font-size: 0.9375rem;
    line-height: 1.7;
    color: var(--gray);
}

/* ========================================
   Testimonials Section
   ======================================== */
.testimonials {
    padding: var(--spacing-3xl) 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
}

.testimonials .section-tag {
    color: var(--white);
}

.testimonials .section-title {
    color: var(--white);
}

.testimonials .section-description {
    color: rgba(255, 255, 255, 0.9);
}

.testimonials-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.testimonial-card {
    background-color: var(--white);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.testimonial-rating {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-md);
}

.testimonial-rating i {
    color: var(--warning);
    font-size: 1.125rem;
}

.testimonial-text {
    font-size: 0.9375rem;
    line-height: 1.7;
    color: var(--gray);
    margin-bottom: var(--spacing-md);
    font-style: italic;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 2px solid var(--light-gray);
}

.author-icon {
    width: 50px;
    height: 50px;
    background-color: var(--light-gray);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.author-icon i {
    font-size: 1.25rem;
    color: var(--primary-color);
}

.author-name {
    font-size: 1rem;
    font-weight: var(--font-weight-semibold);
    color: var(--dark);
    margin-bottom: 2px;
}

.author-location {
    font-size: 0.875rem;
    color: var(--gray);
}

/* ========================================
   Areas Served Section
   ======================================== */
.areas-served {
    padding: var(--spacing-3xl) 0;
    background-color: var(--white);
}

.areas-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: start;
}

.areas-text {
    font-size: 1.0625rem;
    line-height: 1.8;
    color: var(--gray);
    margin-bottom: var(--spacing-md);
}

.cities-list {
    margin: var(--spacing-xl) 0;
    padding: var(--spacing-xl);
    background-color: var(--light-gray);
    border-radius: var(--radius-lg);
}

.cities-title {
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--dark);
    margin-bottom: var(--spacing-md);
}

.cities-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
}

.city-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.9375rem;
    color: var(--dark);
    font-weight: var(--font-weight-medium);
}

.city-item i {
    color: var(--primary-color);
    font-size: 0.875rem;
}

.areas-cta-text {
    font-size: 1rem;
    color: var(--gray);
}

.phone-link {
    color: var(--primary-color);
    font-weight: var(--font-weight-semibold);
}

.phone-link:hover {
    text-decoration: underline;
}

.areas-map {
    position: sticky;
    top: 100px;
}

.map-wrapper {
    height: 500px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

/* ========================================
   FAQ Section
   ======================================== */
.faq {
    padding: var(--spacing-3xl) 0;
    background-color: var(--light-gray);
}

.faq-container {
    max-width: 900px;
    margin: 0 auto;
}

.faq-item {
    background-color: var(--white);
    margin-bottom: var(--spacing-md);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    transition: var(--transition-base);
}

.faq-item:hover {
    box-shadow: var(--shadow-md);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    text-align: left;
    font-size: 1.125rem;
    font-weight: var(--font-weight-semibold);
    color: var(--dark);
    cursor: pointer;
    transition: var(--transition-base);
}

.faq-question:hover {
    color: var(--primary-color);
}

.faq-question i {
    font-size: 1rem;
    color: var(--primary-color);
    transition: var(--transition-base);
    flex-shrink: 0;
    margin-left: var(--spacing-md);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease;
}

.faq-item.active .faq-answer {
    max-height: 500px;
}

.faq-answer p {
    padding: 0 var(--spacing-lg) var(--spacing-lg);
    font-size: 1rem;
    line-height: 1.8;
    color: var(--gray);
}

/* ========================================
   CTA Banner
   ======================================== */
.cta-banner {
    padding: var(--spacing-3xl) 0;
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--secondary-dark) 100%);
}

.cta-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-xl);
}

.cta-title {
    font-size: 2.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--white);
    margin-bottom: var(--spacing-sm);
}

.cta-description {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.95);
}

.cta-buttons .btn-primary {
    background-color: var(--white);
    color: var(--secondary-color);
}

.cta-buttons .btn-primary:hover {
    background-color: var(--light-gray);
}

/* ========================================
   Footer
   ======================================== */
.footer {
    padding: var(--spacing-3xl) 0 var(--spacing-lg);
    background-color: var(--dark);
    color: rgba(255, 255, 255, 0.8);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.25rem;
    font-weight: var(--font-weight-bold);
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.footer-description {
    font-size: 0.9375rem;
    line-height: 1.7;
    margin-bottom: var(--spacing-md);
}

.footer-contact p {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.9375rem;
    margin-bottom: var(--spacing-xs);
}

.footer-contact i {
    color: var(--primary-color);
    width: 20px;
}

.footer-contact a {
    color: rgba(255, 255, 255, 0.8);
}

.footer-contact a:hover {
    color: var(--white);
}

.footer-title {
    font-size: 1.125rem;
    font-weight: var(--font-weight-bold);
    color: var(--white);
    margin-bottom: var(--spacing-md);
}

.footer-links li {
    margin-bottom: var(--spacing-xs);
}

.footer-links a {
    font-size: 0.9375rem;
    color: rgba(255, 255, 255, 0.8);
    transition: var(--transition-base);
}

.footer-links a:hover {
    color: var(--white);
    padding-left: var(--spacing-xs);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: var(--spacing-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.copyright {
    font-size: 0.875rem;
}

.footer-bottom-links {
    display: flex;
    gap: var(--spacing-lg);
}

.footer-bottom-links a {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
}

.footer-bottom-links a:hover {
    color: var(--white);
}

/* ========================================
   Responsive Design
   ======================================== */

/* Tablet - 768px and below */
@media (max-width: 768px) {
    /* Typography */
    .section-title {
        font-size: 2rem;
    }
    
    .section-description {
        font-size: 1rem;
    }
    
    /* Header */
    .nav {
        position: fixed;
        top: 76px;
        left: -100%;
        width: 100%;
        background-color: var(--white);
        box-shadow: var(--shadow-lg);
        transition: var(--transition-base);
        padding: var(--spacing-lg);
    }
    
    .nav.active {
        left: 0;
    }
    
    .nav-list {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }
    
    .header-btn {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    /* Hero */
    .hero {
        min-height: 80vh;
        padding: 6rem 0 3rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-subtitle {
        font-size: 1.375rem;
    }
    
    .hero-description {
        font-size: 1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .hero-features {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    /* About */
    .about-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }
    
    .about-content {
        padding-right: 0;
    }
    
    .about-stats {
        grid-template-columns: repeat(3, 1fr);
        gap: var(--spacing-md);
    }
    
    .stat-number {
        font-size: 2rem;
    }
    
    /* Services */
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }
    
    /* Features */
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }
    
    /* Testimonials */
    .testimonials-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--spacing-md);
    }
    
    /* Areas */
    .areas-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-xl);
    }
    
    .areas-map {
        position: static;
    }
    
    .cities-grid {
        grid-template-columns: 1fr;
    }
    
    /* CTA */
    .cta-content {
        flex-direction: column;
        text-align: center;
    }
    
    .cta-title {
        font-size: 1.75rem;
    }
    
    /* Footer */
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: var(--spacing-lg);
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--spacing-md);
        text-align: center;
    }
}

/* Mobile - 480px and below */
@media (max-width: 480px) {
    /* Typography */
    .section-title {
        font-size: 1.75rem;
    }
    
    /* Hero */
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1.25rem;
    }
    
    /* About */
    .about-stats {
        grid-template-columns: 1fr;
    }
    
    /* Services */
    .services-grid {
        grid-template-columns: 1fr;
    }
    
    /* Features */
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    /* Testimonials */
    .testimonials-grid {
        grid-template-columns: 1fr;
    }
    
    /* CTA */
    .cta-title {
        font-size: 1.5rem;
    }
    
    /* Footer */
    .footer-grid {
        grid-template-columns: 1fr;
    }
}

/* Large Desktop - 1400px and above */
@media (min-width: 1400px) {
    .container {
        max-width: 1320px;
    }
    
    .hero-title {
        font-size: 4rem;
    }
    
    .section-title {
        font-size: 3rem;
    }
}