:root {
    /* Color Palette - ProVolt Brand Colors */
    --primary-blue: #004AAD;
    /* Royal Blue from logo */
    --primary-yellow: #FFD700;
    /* Bright Yellow from logo */
    --dark-blue: #002D6B;
    /* Darker shade for depth */
    --light-blue: #0066CC;
    /* Lighter blue for accents */
    --bg-dark: #0A1628;
    /* Very dark blue for backgrounds */
    --bg-light: #F5F8FC;
    /* Light blue-tinted white */
    --text-primary: #FFFFFF;
    /* White text */
    --text-secondary: #B8C5D6;
    /* Light blue-grey */
    --text-dark: #1A2332;
    /* Dark text for light backgrounds */
    --card-bg: #FFFFFF;
    --shadow-sm: 0 2px 4px rgba(0, 74, 173, 0.1);
    --shadow-md: 0 4px 12px rgba(0, 74, 173, 0.15);
    --shadow-lg: 0 8px 24px rgba(0, 74, 173, 0.2);
    --shadow-yellow: 0 0 30px rgba(255, 215, 0, 0.3);

    /* Spacing */
    --container-padding: 1.5rem;
    --max-width: 1200px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Utilities */
.container {
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* Header */
#main-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    transition: background-color 0.3s ease, backdrop-filter 0.3s ease, padding 0.3s ease, box-shadow 0.3s ease;
    padding: 1.5rem 0;
    background-color: transparent;
}

#main-header.scrolled {
    background-color: rgba(10, 22, 40, 0.95);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    box-shadow: 0 2px 20px rgba(255, 215, 0, 0.1);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    height: 50px;
    width: auto;
    display: block;
    filter: drop-shadow(0 2px 8px rgba(255, 215, 0, 0.3));
    transition: transform 0.3s ease;
}

.logo:hover {
    transform: scale(1.05);
}

/* Hero Section */
.hero-section {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: left;
    background: linear-gradient(135deg, var(--dark-blue) 0%, var(--primary-blue) 50%, var(--bg-dark) 100%);
    overflow: hidden;
}

/* Hero Background Image */
.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('hero-electrician.jpg');
    background-size: cover;
    background-position: center right;
    opacity: 0.25;
    z-index: 0;
}

/* Electrical grid pattern overlay */
.hero-section::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image:
        linear-gradient(rgba(255, 215, 0, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 215, 0, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    opacity: 0.5;
    z-index: 1;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to right, rgba(0, 45, 107, 0.9) 0%, rgba(0, 45, 107, 0.6) 50%, transparent 100%);
    z-index: 2;
}

.hero-content {
    position: relative;
    z-index: 3;
    max-width: 700px;
}

h1 {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
    color: var(--text-primary);
    text-shadow: 2px 2px 8px rgba(0, 0, 0, 0.5);
}

h1 .highlight {
    color: var(--primary-yellow);
    text-shadow: 0 0 20px rgba(255, 215, 0, 0.5);
}

.subheadline {
    font-size: 1.2rem;
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
    max-width: 600px;
    text-shadow: 1px 1px 4px rgba(0, 0, 0, 0.5);
}

.cta-button {
    display: inline-block;
    background: linear-gradient(135deg, var(--primary-yellow) 0%, #FFC700 100%);
    color: var(--dark-blue);
    padding: 1.2rem 3rem;
    border-radius: 50px;
    font-weight: 700;
    font-size: 1.1rem;
    text-decoration: none;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 4px 20px rgba(255, 215, 0, 0.4);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 30px rgba(255, 215, 0, 0.6);
}

/* Lessons Section */
.lessons-section {
    padding: 5rem 0;
    background: linear-gradient(to bottom, var(--bg-light) 0%, #E8EEF7 100%);
    color: var(--text-dark);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
    color: var(--primary-blue);
    position: relative;
    display: inline-block;
    width: 100%;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(to right, var(--primary-yellow), var(--primary-blue));
    border-radius: 2px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-dark);
    opacity: 0.7;
    margin-bottom: 3rem;
    font-size: 1.1rem;
}

.lessons-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

.lesson-card {
    background: var(--card-bg);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    border: 2px solid transparent;
}

.lesson-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-yellow);
}

.lesson-title {
    padding: 1.5rem;
    font-size: 1.1rem;
    font-weight: 600;
    background: linear-gradient(135deg, var(--primary-blue) 0%, var(--light-blue) 100%);
    color: var(--text-primary);
    border-bottom: 3px solid var(--primary-yellow);
}

.video-wrapper {
    position: relative;
    padding-bottom: 56.25%;
    /* 16:9 Aspect Ratio */
    height: 0;
    background-color: #000;
}

.video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/* Footer */
footer {
    background: linear-gradient(135deg, var(--dark-blue) 0%, var(--bg-dark) 100%);
    color: var(--text-secondary);
    padding: 3rem 0;
    text-align: center;
    font-size: 0.95rem;
    border-top: 3px solid var(--primary-yellow);
}

footer p {
    margin: 0;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translate3d(0, 40px, 0);
    }

    to {
        opacity: 1;
        transform: translate3d(0, 0, 0);
    }
}

@keyframes pulse {

    0%,
    100% {
        box-shadow: 0 4px 20px rgba(255, 215, 0, 0.4);
    }

    50% {
        box-shadow: 0 6px 30px rgba(255, 215, 0, 0.7);
    }
}

.fade-in-up {
    opacity: 0;
    animation: fadeInUp 0.8s ease-out forwards;
}

.delay-1 {
    animation-delay: 0.2s;
}

.delay-2 {
    animation-delay: 0.4s;
}

/* Scroll Animation Classes */
.fade-in-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-in-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive Design */
@media (min-width: 768px) {
    h1 {
        font-size: 3.5rem;
    }

    .lessons-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .lessons-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .container {
        padding: 0 2rem;
    }

    .hero-content {
        max-width: 650px;
    }
}

@media (max-width: 767px) {
    h1 {
        font-size: 2rem;
    }

    .subheadline {
        font-size: 1rem;
    }

    .cta-button {
        padding: 1rem 2rem;
        font-size: 1rem;
    }

    .hero-section {
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
    }
}