/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2E86AB;
    --secondary-color: #1B5E7E;
    --accent-color: #D4763A;
    --text-dark: #1a1a2e;
    --text-light: #6c757d;
    --bg-light: #fafbfc;
    --white: #ffffff;
    --shadow: 0 10px 40px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.12);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
}

/* Navigation */
.navbar {
    background: var(--white);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--primary-color);
}

.nav-menu a.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 65%, var(--accent-color) 100%);
    color: var(--white);
    padding: 6rem 2rem;
    position: relative;
    overflow: hidden;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    text-align: center;
    position: relative;
    z-index: 10;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1.5rem;
    animation: fadeInUp 0.8s ease;
}

.hero-subtitle {
    font-size: 1.3rem;
    margin-bottom: 2.5rem;
    opacity: 0.95;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-graphic {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-top: 3rem;
    flex-wrap: wrap;
}

.floating-card {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    padding: 1.5rem 2rem;
    border-radius: 15px;
    animation: float 3s ease-in-out infinite;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

.floating-card.delay-1 {
    animation-delay: 1s;
}

.floating-card.delay-2 {
    animation-delay: 2s;
}

.floating-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.floating-card p {
    font-size: 0.9rem;
    opacity: 0.9;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-15px);
    }
}

/* CTA Button */
.cta-button {
    display: inline-block;
    background: var(--white);
    color: var(--primary-color);
    padding: 1rem 3rem;
    text-decoration: none;
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: bold;
    transition: all 0.3s ease;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.2);
    animation: fadeInUp 0.8s ease 0.4s both;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(46, 134, 171, 0.35);
}

.cta-button:focus-visible {
    outline: 3px solid rgba(212, 118, 58, 0.5);
    outline-offset: 3px;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 4rem 2rem;
}

section {
    margin-bottom: 5rem;
}

h2 {
    font-size: 2.5rem;
    color: var(--text-dark);
    margin-bottom: 1.5rem;
    text-align: center;
}

.lead {
    font-size: 1.2rem;
    color: var(--text-light);
    text-align: center;
    max-width: 800px;
    margin: 0 auto 2rem;
}

/* Highlight Box */
.highlight-box {
    background: linear-gradient(135deg, rgba(46, 134, 171, 0.12), rgba(27, 94, 126, 0.12));
    border-left: 4px solid var(--primary-color);
    padding: 1.5rem;
    border-radius: 10px;
    margin: 2rem auto;
    max-width: 800px;
}

/* Features Grid */
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature-card {
    background: var(--white);
    padding: 2rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    color: var(--primary-color);
    font-size: 1.4rem;
    margin-bottom: 1rem;
}

.feature-card p {
    color: var(--text-light);
    line-height: 1.8;
}

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

.step {
    text-align: center;
}

.step-number {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: bold;
    margin: 0 auto 1.5rem;
    box-shadow: 0 5px 20px rgba(46, 134, 171, 0.3);
}

.step h3 {
    color: var(--text-dark);
    margin-bottom: 1rem;
}

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

/* CTA Section */
.cta-section {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color), var(--accent-color));
    color: var(--white);
    padding: 4rem 2rem;
    border-radius: 20px;
    text-align: center;
}

.cta-section h2 {
    color: var(--white);
}

.cta-section p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.cta-section .cta-button {
    background: var(--white);
    color: var(--primary-color);
}

/* Footer */
footer {
    background: var(--text-dark);
    color: var(--white);
    padding: 3rem 2rem 1rem;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    color: var(--white);
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.footer-section p,
.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    line-height: 2;
}

.footer-section a:hover {
    color: var(--white);
    text-decoration: underline;
}

.footer-section ul {
    list-style: none;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

/* Content sections */
.content-section {
    background: var(--white);
    padding: 3rem;
    border-radius: 15px;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

.content-section h3 {
    color: var(--primary-color);
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
}

.content-section h4 {
    color: var(--secondary-color);
    font-size: 1.2rem;
    margin: 1.5rem 0 0.8rem;
}

.content-section ul,
.content-section ol {
    margin-left: 2rem;
    color: var(--text-light);
}

.content-section li {
    margin-bottom: 0.8rem;
}

/* Formula Box */
.formula-box {
    background: #f8f9fa;
    border-left: 4px solid var(--primary-color);
    padding: 1.5rem;
    margin: 2rem 0;
    border-radius: 5px;
    overflow-x: auto;
    font-family: 'Courier New', Courier, monospace;
    font-size: 0.95rem;
    line-height: 1.8;
}

/* Calculator embed */
.calculator-embed {
    width: 100%;
    height: 1200px;
    border: none;
    border-radius: 15px;
    box-shadow: var(--shadow-lg);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .nav-menu {
        flex-direction: column;
        gap: 1rem;
    }

    .features-grid,
    .steps {
        grid-template-columns: 1fr;
    }

    h2 {
        font-size: 2rem;
    }

    .container {
        padding: 2rem 1rem;
    }
}