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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
}

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

/* Show/hide based on screen size */
.mobile-only {
    display: none;
}

.desktop-only {
    display: block;
}

/* Navigation */
#navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background-color: #ffffff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2c3e50;
}

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

.nav-links a {
    text-decoration: none;
    color: #555;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: #3498db;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: #3498db;
    transition: width 0.3s ease;
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url('https://images.unsplash.com/photo-1734079692160-fcbe4be6ab96?q=80&w=1740&auto=format&fit=crop&ixlib=rb-4.1.0&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D&auto=format&fit=crop&w=1920&q=80');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    color: white;
    text-align: center;
    padding-top: 80px;
    position: relative;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    animation: fadeInUp 0.8s ease;
}

.hero .tagline {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    opacity: 0.95;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero .description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    animation: fadeInUp 0.8s ease 0.4s both;
}

.cta-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    background-color: white;
    color: #667eea;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    animation: fadeInUp 0.8s ease 0.6s both;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.2);
}

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

/* Photo Credit Icon */
.photo-credit-icon {
    position: absolute;
    bottom: 20px;
    left: 20px;
    width: 32px;
    height: 32px;
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    z-index: 100;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.photo-credit-icon:hover {
    background-color: rgba(255, 255, 255, 1);
    transform: scale(1.1);
}

.photo-credit-icon span {
    color: #2c3e50;
    font-weight: bold;
    font-size: 16px;
    font-style: italic;
}

/* Photo Credit Modal */
.photo-credit-modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    justify-content: center;
    align-items: center;
}

.modal-content {
    background-color: white;
    padding: 30px;
    border-radius: 10px;
    max-width: 500px;
    width: 90%;
    position: relative;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    color: #333;
}

.close-modal {
    position: absolute;
    top: 10px;
    right: 20px;
    font-size: 32px;
    font-weight: bold;
    color: #999;
    cursor: pointer;
    transition: color 0.3s ease;
}

.close-modal:hover {
    color: #333;
}

.modal-content h3 {
    margin-bottom: 20px;
    color: #2c3e50;
    font-size: 1.5rem;
}

.modal-content p {
    margin-bottom: 12px;
    line-height: 1.6;
}

.modal-content a {
    color: #3498db;
    text-decoration: none;
    transition: color 0.3s ease;
}

.modal-content a:hover {
    color: #2980b9;
    text-decoration: underline;
}

.license-info {
    margin-top: 20px;
    padding-top: 15px;
    border-top: 1px solid #eee;
}

.license-details {
    font-size: 0.9rem;
    color: #666;
    line-height: 1.5;
}

/* About Section */
#about {
    padding: 100px 20px;
    background-color: #f8f9fa;
}

#about h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 2rem;
    color: #2c3e50;
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
}

.about-content > p {
    font-size: 1.2rem;
    text-align: center;
    margin-bottom: 3rem;
    color: #555;
    line-height: 1.8;
}

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

.feature {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.feature h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.feature p {
    color: #666;
    line-height: 1.6;
}

/* Survey Section */
#survey {
    padding: 100px 20px;
    background: linear-gradient(135deg, #eaf4fb 0%, #f0f7ee 100%);
}

#survey h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.survey-intro {
    text-align: center;
    font-size: 1.2rem;
    color: #555;
    margin-bottom: 3rem;
    max-width: 650px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}

/* Contact Section */
#contact {
    padding: 100px 20px;
    background-color: white;
}

#contact h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.contact-intro {
    text-align: center;
    font-size: 1.2rem;
    color: #555;
    margin-bottom: 3rem;
}

/* Desktop iframe container */
.form-container {
    max-width: 800px;
    margin: 0 auto;
}

.form-container iframe {
    border-radius: 10px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    display: block;
}

/* Mobile button CTA */
.form-cta-container {
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
    background: white;
    border-radius: 16px;
    padding: 2.5rem 2rem;
    box-shadow: 0 5px 30px rgba(0, 0, 0, 0.08);
}

.form-cta-desc {
    font-size: 1.1rem;
    color: #555;
    margin-bottom: 2rem;
    line-height: 1.7;
}

.form-link-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    background-color: #3498db;
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease, background-color 0.3s ease;
}

.form-link-button:hover {
    background-color: #2980b9;
    transform: translateY(-3px);
    box-shadow: 0 10px 25px rgba(52, 152, 219, 0.35);
}

.form-link-button--dark {
    background-color: #2c3e50;
}

.form-link-button--dark:hover {
    background-color: #1a252f;
    box-shadow: 0 10px 25px rgba(44, 62, 80, 0.35);
}

/* Footer */
footer {
    background-color: #343536;
    color: white;
    padding: .5rem 20px;
    text-align: center;
}

footer p {
    margin: 0;
    font-size: 0.95rem;
}

/* ── Mobile: swap iframe for buttons ── */
@media (max-width: 768px) {
    .desktop-only {
        display: none !important;
    }

    .mobile-only {
        display: block !important;
    }

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

    .nav-links {
        gap: 1rem;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero .tagline {
        font-size: 1.2rem;
    }

    .hero .description {
        font-size: 1rem;
    }

    #about h2,
    #survey h2,
    #contact h2 {
        font-size: 2rem;
    }

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

    #about,
    #survey,
    #contact {
        padding: 60px 20px;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.2rem;
    }

    .nav-links {
        gap: 0.8rem;
        font-size: 0.9rem;
    }

    .hero h1 {
        font-size: 1.8rem;
    }

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

    .cta-button {
        padding: 0.8rem 2rem;
    }
}