/* CardioLab Light Mode Design with Orange Gradient Theme */
:root {
    /* Orange gradient variations */
    --primary-gradient: linear-gradient(135deg, #1a1a1a 0%, #333333 100%);
    --accent-gradient: linear-gradient(135deg, #ff8a50 0%, #ff6b35 100%);
    --success-gradient: linear-gradient(135deg, #ff9500 0%, #ff6b35 100%);
    --hero-gradient: linear-gradient(135deg, #ffffff 0%, #f8f9fa 50%, #ffffff 100%);
    --card-gradient: linear-gradient(145deg, #ffffff 0%, #f8f9fa 100%);
    --feature-gradient: linear-gradient(135deg, #ff6b35 0%, #ff8c00 50%, #ffa500 100%);
    --background-gradient: linear-gradient(180deg, #ffffff 0%, #f8f9fa 100%);
    --section-gradient: linear-gradient(135deg, #f8f9fa 0%, #ffffff 50%, #f1f3f4 100%);

    /* Light mode colors */
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --text-muted: #999999;

    --background: #ffffff;
    --background-secondary: #FFFFFF;
    --background-tertiary: #f1f3f4;

    --border-light: #e1e5e9;
    --border-medium: #d1d9e0;

    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--background-gradient);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-light);
    z-index: 1000;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    font-size: 20px;
    color: var(--text-primary);
}

.logo-icon-img {
    width: 32px;
    height: 32px;
    border-radius: 8px;
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 15px;
    transition: all 0.2s ease;
    position: relative;
}

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

.nav-download {
    background: var(--primary-gradient);
    color: white !important;
    padding: 10px 20px;
    border-radius: var(--radius-lg);
    font-weight: 600;
    transition: all 0.3s ease;
}

.nav-download:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* Hero Section */
.hero {
    padding: 140px 0 100px;
    background: var(--hero-gradient);
    position: relative;
    overflow: hidden;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content {
    text-align: left;
}

.hero-title {
    font-size: clamp(3rem, 8vw, 5rem);
    font-weight: 700;
    line-height: 1.1;
    margin-bottom: 24px;
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.gradient-text {
    color: var(--text-primary);
}

.hero-subtitle {
    font-size: 20px;
    color: var(--text-secondary);
    max-width: 500px;
    margin-bottom: 48px;
    line-height: 1.6;
    animation: fadeInUp 0.6s ease-out 0.4s both;
}

.hero-download-btn {
    animation: fadeInUp 0.6s ease-out 0.6s both;
}

.hero-download-btn img {
    height: 60px;
    transition: all 0.3s ease;
}

.hero-download-btn:hover img {
    transform: scale(1.05);
}


/* Hero Phone */
.hero-phone {
    display: flex;
    justify-content: center;
    animation: fadeInUp 0.8s ease-out 0.8s both;
}

.phone-container {
    position: relative;
    animation: float 6s ease-in-out infinite;
}

.hero-phone-img {
    width: 400px;
    height: auto;
    object-fit: contain;
}


/* Features Section */
.features {
    padding: 120px 0;
    background: var(--section-gradient);
}

.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto 80px;
}

.section-title {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
}

.feature-item {
    display: flex;
    gap: 24px;
    padding: 32px;
    background: var(--card-gradient);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-light);
    transition: all 0.3s ease;
}

.feature-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(145deg, #ffffff 0%, #f1f3f4 100%);
    border-color: var(--border-medium);
}

.feature-visual {
    flex-shrink: 0;
}

.feature-icon-bg {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-md);
    background: var(--primary-gradient);
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-icon {
    font-size: 24px;
    filter: grayscale(100%) brightness(0) invert(1);
}

.feature-content {
    flex: 1;
}

.feature-content h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.feature-content p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Screenshots Section */
.screenshots {
    padding: 120px 0;
    background: linear-gradient(180deg, var(--background-secondary) 0%, var(--background) 100%);
}

.screenshots-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
    margin-top: 80px;
}

.screenshot-item {
    text-align: center;
    background: white;
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 32px;
    box-shadow: var(--shadow-md);
    transition: all 0.3s ease;
}

.screenshot-item:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
    border-color: var(--border-medium);
    background: white;
}

.screenshot-img {
    width: 200px;
    height: 400px;
    object-fit: cover;
    border-radius: 24px;
    margin: 0 auto 24px;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s ease;
}

.screenshot-item:hover .screenshot-img {
    transform: scale(1.02);
}

.screenshot-item h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.screenshot-item p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* Download Section */
.download-section {
    padding: 120px 0;
    background: var(--section-gradient);
    color: var(--text-primary);
    text-align: center;
}

.download-content h2 {
    font-size: clamp(2.5rem, 5vw, 3.5rem);
    font-weight: 700;
    margin-bottom: 20px;
}

.download-content p {
    font-size: 18px;
    margin-bottom: 40px;
    color: var(--text-secondary);
}

.app-store-button img {
    height: 60px;
    transition: all 0.3s ease;
    filter: brightness(0.9);
}

.app-store-button:hover img {
    transform: scale(1.05);
    filter: brightness(1);
}


/* Footer */
.footer {
    padding: 60px 0;
    background: linear-gradient(180deg, var(--background-secondary) 0%, var(--background) 100%);
    border-top: 1px solid var(--border-light);
}

.footer-content {
    text-align: center;
}

.footer-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    font-weight: 600;
    font-size: 20px;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.footer-text {
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.footer-links {
    display: flex;
    justify-content: center;
    gap: 32px;
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.2s ease;
}

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

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

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-12px);
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    .nav-container {
        padding: 0 20px;
    }

    .nav-links {
        display: none;
    }

    .hero {
        padding: 120px 0 80px;
    }

    .hero-container {
        padding: 0 20px;
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }

    .hero-content {
        text-align: center;
    }

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

    .feature-item {
        flex-direction: column;
        text-align: center;
    }

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


    .footer-links {
        flex-direction: column;
        gap: 16px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .feature-item {
        padding: 24px 20px;
    }

    .phone-container {
        width: 240px;
        height: 480px;
    }

    .screenshot-img {
        width: 180px;
        height: 360px;
    }
}