* {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Arial, sans-serif;
    background: linear-gradient(120deg, #f8fafc 0%, #e0e7ef 100%);
    color: #222;
    margin: 0;
    padding: 0;
    line-height: 1.6;
}

.header {
    background: #1a4d2e;
    color: white;
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
}

.nav {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
}

.nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s;
}

.nav a:hover {
    color: #b2dfdb;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem;
}

.hero {
    background: white;
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.08);
    padding: 3rem 2rem;
    text-align: center;
    margin-bottom: 2rem;
}

.hero h1 {
    color: #1a4d2e;
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero .subtitle {
    color: #2b7a78;
    font-size: 1.3rem;
    margin-bottom: 2rem;
    font-weight: 500;
}

.cta-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 2rem;
}

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.btn-primary {
    background: #2b7a78;
    color: white;
}

.btn-primary:hover {
    background: #1a4d2e;
    transform: translateY(-2px);
}

.btn-secondary {
    background: white;
    color: #2b7a78;
    border: 2px solid #2b7a78;
}

.btn-secondary:hover {
    background: #2b7a78;
    color: white;
    transform: translateY(-2px);
}

.btn-app-store {
    display: inline-flex;
    align-items: center;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
}

.btn-app-store:hover {
    transform: translateY(-2px);
    text-decoration: none;
}

.app-store-section {
    background: linear-gradient(135deg, #1a4d2e 0%, #2b7a78 100%);
    color: white;
    text-align: center;
    padding: 2rem;
}

.app-store-section h2 {
    color: white;
    border-bottom: 3px solid white;
}

.app-store-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 1.5rem;
}

.section {
    background: white;
    border-radius: 12px;
    box-shadow: 0 2px 16px rgba(0,0,0,0.05);
    padding: 2rem;
    margin-bottom: 2rem;
}

.section h2 {
    color: #1a4d2e;
    font-size: 2rem;
    margin-bottom: 1rem;
    border-bottom: 3px solid #2b7a78;
    padding-bottom: 0.5rem;
}

.section h3 {
    color: #2b7a78;
    font-size: 1.3rem;
    margin-top: 1.5rem;
    margin-bottom: 0.8rem;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.feature-card {
    background: #f8fafc;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #2b7a78;
}

.feature-card strong {
    color: #1a4d2e;
    display: block;
    margin-bottom: 0.5rem;
}

.tutorials-section {
    background: linear-gradient(135deg, #2b7a78 0%, #1a4d2e 100%);
    color: white;
    text-align: center;
}

.tutorials-section h2 {
    color: white;
    border-bottom: 3px solid white;
}

.tutorials-content {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 2rem;
    flex-wrap: wrap;
}

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

ul {
    margin-left: 1.5em;
}

li {
    margin-bottom: 0.5rem;
}

a {
    color: #2b7a78;
    text-decoration: none;
    font-weight: 500;
}

a:hover {
    text-decoration: underline;
}

.footer {
    background: #1a4d2e;
    color: white;
    padding: 2rem 0;
    text-align: center;
}

.footer-content {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 2rem;
}

.footer-links {
    display: flex;
    gap: 2rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 1rem;
}

.footer-links a {
    color: white;
    font-weight: 500;
}

.footer-links a:hover {
    color: #b2dfdb;
}

.footer-authors {
    margin-top: 1.5rem;
    margin-bottom: 1rem;
    padding-top: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
}

.footer-authors h3 {
    font-size: 1rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.footer-authors-links {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
    flex-wrap: wrap;
}

.footer-authors-links a {
    color: white;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
    transition: color 0.2s;
}

.footer-authors-links a:hover {
    color: #b2dfdb;
}

.footer-authors-links a::before {
    content: "💼";
    font-size: 1.1rem;
}

.lang-toggle {
    background: transparent;
    border: 2px solid white;
    color: white;
    padding: 0.4rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all 0.3s;
    font-size: 0.9rem;
}

.lang-toggle:hover {
    background: white;
    color: #1a4d2e;
}

.example-files-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.example-file-card {
    background: #f8fafc;
    padding: 1.5rem;
    border-radius: 8px;
    border-left: 4px solid #2b7a78;
}

.example-file-card h3 {
    color: #1a4d2e;
    margin-top: 0;
    margin-bottom: 0.8rem;
}

.example-file-card p {
    margin-bottom: 1rem;
}

.example-file-card .btn {
    display: inline-block;
    margin-top: 0.5rem;
}

/* Video container for embedded YouTube videos */
.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    overflow: hidden;
    max-width: 100%;
    background: #000;
    border-radius: 8px;
    margin: 2rem 0;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
    border-radius: 8px;
}

/* App screenshot styling */
.app-screenshot {
    display: block;
    max-width: 300px;
    margin: 1.5rem auto;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

.app-screenshot-wide {
    display: block;
    max-width: 100%;
    margin: 1.5rem auto;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

.screenshot-caption {
    text-align: center;
    font-style: italic;
    color: #666;
    margin-top: 0.5rem;
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero .subtitle {
        font-size: 1.1rem;
    }
    
    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .nav {
        margin-top: 1rem;
        justify-content: center;
    }
    
    .header-content {
        flex-direction: column;
        text-align: center;
    }
}