:root {
    --primary-color: #7b2cbf;
    --primary-light: #9d4edd;
    --primary-dark: #5a189a;
    --bg-color: #ffffff;
    --text-main: #2d3436;
    --text-muted: #636e72;
    --gray-light: #f8f9fa;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

a {
    text-decoration: none;
    color: inherit;
    transition: color 0.3s ease;
}

/* Typography */
h1 {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    color: var(--primary-dark);
    margin-bottom: 20px;
}

h2.section-title {
    font-size: 2.5rem;
    text-align: center;
    color: var(--primary-dark);
    margin-bottom: 50px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 15px 30px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    border-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(123, 44, 191, 0.2);
}

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

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

/* Header */
.navbar {
    padding: 20px 0;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 100;
}

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

.logo {
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary-color);
    letter-spacing: -1px;
}

.nav-links a {
    margin: 0 15px;
    font-weight: 600;
}

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

.nav-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

.login-link {
    font-weight: 600;
    color: var(--text-muted);
}

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

/* Hero Section */
.hero {
    padding: 100px 0;
    background: linear-gradient(135deg, rgba(123,44,191,0.05) 0%, rgba(255,255,255,1) 100%);
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.hero-content p {
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: 40px;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    margin-bottom: 40px;
}

.hero-benefits {
    display: flex;
    gap: 20px;
    font-weight: 600;
    color: var(--primary-dark);
}

.hero-image-lungs {
    width: 50%;
    height: auto;
    max-height: 500px;
    object-fit: cover;
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(123,44,191,0.2);
    transition: transform 0.8s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    display: block;
    margin: 0 auto;
}

.hero-image-lungs:hover {
    transform: scale(1.05);
}

/* Steps Section */
.steps {
    padding: 100px 0;
    background-color: var(--gray-light);
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.step-card {
    background: white;
    padding: 40px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0,0,0,0.03);
    transition: transform 0.3s ease;
}

.step-card:hover {
    transform: translateY(-10px);
}

.step-number {
    width: 60px;
    height: 60px;
    background-color: var(--primary-color);
    color: white;
    font-size: 1.5rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    margin: 0 auto 20px;
}

.step-card h3 {
    color: var(--primary-dark);
    margin-bottom: 15px;
    font-size: 1.3rem;
}

/* Testimonials */
.testimonials {
    padding: 100px 0;
}

.testimonial-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.testimonial-card {
    padding: 30px;
    border-left: 4px solid var(--primary-color);
    background: var(--gray-light);
    border-radius: 0 10px 10px 0;
    transition: background 0.3s ease;
}

.testimonial-card:hover {
    background: white;
    box-shadow: 0 10px 30px rgba(0,0,0,0.05);
}

.quote {
    font-style: italic;
    margin-bottom: 20px;
    color: var(--text-main);
}

.author {
    font-weight: 600;
    color: var(--primary-color);
}

/* Footer */
.footer {
    background-color: var(--primary-dark);
    color: white;
    padding: 80px 0 20px;
}

.footer-container {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 50px;
    margin-bottom: 50px;
}

.footer .logo {
    color: white;
    margin-bottom: 20px;
    display: block;
}

.footer-col h4 {
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.footer-col a {
    display: block;
    color: rgba(255,255,255,0.8);
    margin-bottom: 10px;
}

.footer-col a:hover {
    color: white;
    padding-left: 5px;
}

.footer-col p {
    color: rgba(255,255,255,0.8);
    margin-bottom: 10px;
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.6);
}

/* Mobile Menu Button */
.mobile-nav-actions {
    display: none;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    justify-content: space-around;
    width: 30px;
    height: 25px;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 1000;
}

.mobile-menu-btn span {
    width: 100%;
    height: 3px;
    background: var(--primary-dark);
    border-radius: 5px;
    transition: all 0.3s linear;
    transform-origin: 1px;
}

/* Responsive */
@media (max-width: 900px) {
    .hero-container, .steps-grid, .testimonial-grid, .footer-container {
        grid-template-columns: 1fr;
    }
    
    h1 {
        font-size: 2.5rem;
    }

    .nav-actions {
        display: none; /* Hide actions on small screens if they crowd the header, user can use the menu */
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .mobile-nav-actions {
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: 15px;
        margin-top: 20px;
        width: 100%;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 100%;
        max-width: 300px;
        background: white;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 30px;
        box-shadow: -5px 0 30px rgba(0,0,0,0.1);
        transition: right 0.3s ease;
        z-index: 999;
    }

    .nav-links.active {
        right: 0;
    }

    .nav-links a {
        font-size: 1.5rem;
        margin: 0;
    }

    /* Hamburger animation */
    .mobile-menu-btn.active span:first-child {
        transform: rotate(45deg);
    }
    .mobile-menu-btn.active span:nth-child(2) {
        opacity: 0;
    }
    .mobile-menu-btn.active span:nth-child(3) {
        transform: rotate(-45deg);
    }
}