:root {
    --primary-color: #2563eb;
    --primary-color-dark: #1d4ed8;
    --secondary-color: #f9fafb;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --white: #ffffff;
    --max-width: 1200px;
}

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

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--white);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header */
.header {
    background-color: var(--white);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 100;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-menu {
    display: flex;
    list-style: none;
}

.nav-item {
    margin-left: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 400;
    transition: color 0.3s ease;
}

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

.hamburger {
    display: none;
    cursor: pointer;
}

.bar {
    display: block;
    width: 25px;
    height: 3px;
    margin: 5px auto;
    -webkit-transition: all 0.3s ease-in-out;
    transition: all 0.3s ease-in-out;
    background-color: var(--text-dark);
}

/* Hero Section */
.hero {
    background: linear-gradient(rgba(37, 99, 235, 0.7), rgba(29, 78, 216, 0.7)), url('https://images.unsplash.com/photo-1558494949-ef010cbdcc31?q=80&w=2070') no-repeat center center/cover;
    color: var(--white);
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding-top: 70px; /* To offset header */
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero-content p {
    font-size: 1.25rem;
    font-weight: 300;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 700;
    transition: background-color 0.3s ease;
}

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

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

/* Sections */
section {
    padding: 6rem 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--primary-color);
}

/* Services Section */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.service-card {
    background: var(--white);
    padding: 2rem;
    text-align: center;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

.service-icon img {
    border-radius: 50%;
    margin-bottom: 1rem;
}

.service-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.service-card p {
    color: var(--text-light);
}

/* About Section */
.bg-light {
    background-color: var(--secondary-color);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

/* Contact Section */
.contact-content {
    text-align: center;
}

.contact-content p {
    font-size: 1.1rem;
    margin-bottom: 1rem;
}

.contact-content a {
    color: var(--primary-color);
    text-decoration: none;
}

.contact-content a:hover {
    text-decoration: underline;
}


/* Footer */
.footer {
    background-color: var(--text-dark);
    color: var(--white);
    text-align: center;
    padding: 2rem 0;
}

/* White Papers Section */
.white-papers {
    background-color: var(--white);
}

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

@media (min-width: 992px) {
    .white-papers-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

.white-paper-card {
    background: var(--secondary-color);
    padding: 2.5rem;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    text-align: center;
    border: 1px solid #e5e7eb;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.white-paper-card h3 {
    font-size: 1.75rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.white-paper-card p {
    margin-bottom: 2rem;
    color: var(--text-light);
    font-size: 1.1rem;
}

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

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


/* Article Page */
.article-section {
    padding: 120px 0 6rem; /* More padding top for fixed header */
    background-color: var(--secondary-color);
}

.article-content {
    max-width: 800px;
    margin: 0 auto;
    background: var(--white);
    padding: 3rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.article-title {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
    line-height: 1.2;
}

.article-meta {
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 2.5rem;
}

.article-content h2 {
    font-size: 1.75rem;
    margin-top: 2.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 0.5rem;
}

.article-content p {
    margin-bottom: 1.25rem;
    line-height: 1.8;
}

.article-content ul {
    list-style-position: outside;
    padding-left: 1.5rem;
    margin-bottom: 1.25rem;
}

.article-content li {
    margin-bottom: 0.75rem;
    padding-left: 0.5rem;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--white);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-item {
        margin: 2.5rem 0;
    }

    .hamburger {
        display: block;
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }
}