:root {
    /* Colors */
    --primary-color: #34C7B5;
    --primary-dark: #2aa896;
    --primary-light: #5dd4c4;
    --secondary-color: #34C7B5;
    --accent-color: #60A5FA;
    --text-dark: #4a4a4a;
    --text-medium: #6b6b6b;
    --text-light: #8c8c8c;
    --bg-white: #ffffff;
    --bg-light: #f9f9f9;
    --bg-dark: #223363;
    --border-color: #e0e0e0;
    --shadow: rgba(0, 0, 0, 0.1);
    --shadow-medium: rgba(0, 0, 0, 0.15);
    --shadow-large: rgba(0, 0, 0, 0.2);
    
    /* Spacing */
    --header-height: 4rem;
    --section-padding: 5rem 0;
    --container-max-width: 1200px;
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 2rem;
    --font-size-4xl: 2.5rem;
    --font-size-5xl: 3rem;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
}

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

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    font-family: var(--font-primary);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-white);
    overflow-x: hidden;
}

.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Header & Navigation */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--bg-white);
    box-shadow: 0 2px 10px var(--shadow);
    z-index: 1000;
    transition: var(--transition-base);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: var(--header-height);
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--primary-color);
}

.nav-logo i {
    font-size: var(--font-size-2xl);
}

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

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition-fast);
}

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

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

.nav-toggle {
    display: none;
    font-size: var(--font-size-2xl);
    color: var(--primary-color);
    cursor: pointer;
}

/* Hero Section */
.hero {
    margin-top: var(--header-height);
    padding: 4rem 0;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    min-height: calc(100vh - var(--header-height));
    display: flex;
    align-items: center;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-title {
    font-size: var(--font-size-5xl);
    font-weight: 900;
    line-height: 1.2;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.hero-subtitle {
    font-size: var(--font-size-xl);
    color: var(--text-medium);
    margin-bottom: 2rem;
}

.hero-features {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.hero-feature {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    color: var(--primary-color);
}

.hero-feature i {
    font-size: var(--font-size-xl);
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 0.875rem 2rem;
    border-radius: var(--radius-full);
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition-base);
    cursor: pointer;
    border: 2px solid transparent;
    font-size: var(--font-size-base);
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--bg-white);
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 10px 20px var(--shadow-medium);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-outline:hover {
    background-color: var(--primary-color);
    color: var(--bg-white);
}

.btn-full {
    width: 100%;
}

.hero-image {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.floating-card {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: var(--radius-xl);
    box-shadow: 0 20px 60px var(--shadow-large);
    display: flex;
    align-items: center;
    gap: 1.5rem;
    animation: float 3s ease-in-out infinite;
}

.floating-card i {
    font-size: 3rem;
    color: var(--primary-color);
}

.card-content h4 {
    font-size: var(--font-size-xl);
    margin-bottom: 0.25rem;
}

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

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

/* Section Styles */
.section {
    padding: var(--section-padding);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-tag {
    display: inline-block;
    padding: 0.5rem 1rem;
    background-color: var(--primary-light);
    color: var(--bg-white);
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: var(--font-size-sm);
    margin-bottom: 1rem;
}

.section-title {
    font-size: var(--font-size-4xl);
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.section-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-medium);
    max-width: 700px;
    margin: 0 auto;
}

/* Vitals Section */
.vitals {
    background-color: var(--bg-light);
}

.comparison-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
    margin-bottom: 4rem;
}

.comparison-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: 0 4px 20px var(--shadow);
    transition: var(--transition-base);
}

.comparison-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px var(--shadow-medium);
}

.comparison-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1rem;
    border-bottom: 2px solid var(--border-color);
}

.comparison-header i {
    font-size: var(--font-size-2xl);
}

.comparison-header.old i {
    color: var(--accent-color);
}

.comparison-header.new i {
    color: var(--secondary-color);
}

.comparison-header h3 {
    font-size: var(--font-size-xl);
}

.comparison-list {
    list-style: none;
}

.comparison-list li {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

.comparison-list li:last-child {
    border-bottom: none;
}

.comparison-list i {
    font-size: var(--font-size-xl);
    color: var(--primary-color);
}

/* Demo Section */
.demo-section {
    margin: 5rem 0;
    padding: 4rem 0;
    background: linear-gradient(135deg, rgba(52, 199, 181, 0.05) 0%, rgba(52, 199, 181, 0.1) 100%);
    border-radius: var(--radius-xl);
}

.demo-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 4rem;
    align-items: center;
}

.demo-text {
    padding-right: 2rem;
}

.demo-title {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.demo-subtitle {
    font-size: var(--font-size-lg);
    color: var(--text-medium);
    margin-bottom: 2rem;
    line-height: 1.7;
}

.demo-features {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.demo-features li {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    font-size: var(--font-size-base);
    line-height: 1.7;
    color: var(--text-dark);
}

.demo-features li i {
    font-size: var(--font-size-xl);
    color: var(--primary-color);
    margin-top: 0.2rem;
    flex-shrink: 0;
}

.demo-features strong {
    color: var(--primary-color);
}

.demo-image {
    position: relative;
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: 0 15px 40px var(--shadow-large);
    transition: var(--transition-base);
    max-width: 320px;
    margin: 0 auto;
}

.demo-image:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 20px 50px var(--shadow-large);
}

.demo-image img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: var(--radius-xl);
}

.demo-badge {
    position: absolute;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%);
    background: var(--primary-color);
    color: var(--bg-white);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    font-size: var(--font-size-xs);
    box-shadow: 0 4px 20px rgba(52, 199, 181, 0.4);
    animation: pulse 2s ease-in-out infinite;
}

.demo-badge i {
    font-size: var(--font-size-sm);
}

@keyframes pulse {
    0%, 100% {
        box-shadow: 0 4px 20px rgba(52, 199, 181, 0.4);
    }
    50% {
        box-shadow: 0 4px 30px rgba(52, 199, 181, 0.6);
    }
}

/* Capabilities */
.capabilities {
    margin-top: 4rem;
}

.capabilities-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    text-align: center;
    margin-bottom: 2rem;
}

.capabilities-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.capability-card {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: 0 4px 15px var(--shadow);
    transition: var(--transition-base);
    position: relative;
}

.capability-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 35px var(--shadow-medium);
}

.capability-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-3xl);
    color: var(--bg-white);
}

.capability-card h4 {
    font-size: var(--font-size-lg);
    margin-bottom: 0.5rem;
}

.capability-detail {
    color: var(--text-light);
    font-size: var(--font-size-sm);
}

.fda-badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background-color: var(--secondary-color);
    color: var(--bg-white);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 700;
    margin-top: 0.5rem;
}

.capability-card.fda-cleared {
    border: 2px solid var(--secondary-color);
}

/* Wearables Section */
.wearables {
    background-color: var(--bg-white);
}

.wearables-intro {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: var(--bg-white);
    padding: 3rem;
    border-radius: var(--radius-xl);
    margin-bottom: 4rem;
}

.wearables-intro h3 {
    font-size: var(--font-size-2xl);
    margin-bottom: 1rem;
}

.wearables-intro p {
    font-size: var(--font-size-lg);
    line-height: 1.8;
    margin-bottom: 1rem;
}

/* Devices Section */
.devices-section {
    margin-top: 4rem;
    margin-bottom: 4rem;
}

.devices-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-dark);
}

.devices-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.5rem;
    max-width: 1400px;
    margin: 0 auto;
}

.device-card {
    background: var(--bg-white);
    padding: 2.5rem;
    border-radius: var(--radius-xl);
    box-shadow: 0 10px 30px var(--shadow-medium);
    transition: var(--transition-base);
    border: 2px solid transparent;
}

.device-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px var(--shadow-large);
    border-color: var(--primary-color);
}

.device-header {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
    padding-bottom: 1.5rem;
    border-bottom: 2px solid var(--bg-light);
}

.device-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-3xl);
    color: var(--bg-white);
    flex-shrink: 0;
}

.device-header h4 {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-dark);
}

.device-description {
    font-size: var(--font-size-base);
    line-height: 1.8;
    color: var(--text-medium);
    margin-bottom: 1.5rem;
}

.device-features {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.device-features li {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    font-size: var(--font-size-base);
    color: var(--text-dark);
    line-height: 1.6;
}

.device-features li i {
    font-size: var(--font-size-lg);
    color: var(--primary-color);
    margin-top: 0.15rem;
    flex-shrink: 0;
}

/* HRV Section */
.hrv-section {
    margin-top: 4rem;
}

.hrv-title {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    text-align: center;
    margin-bottom: 1rem;
}

.hrv-subtitle {
    text-align: center;
    font-size: var(--font-size-lg);
    color: var(--text-medium);
    margin-bottom: 3rem;
}

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

.hrv-card {
    background: var(--bg-light);
    padding: 2rem;
    border-radius: var(--radius-lg);
    transition: var(--transition-base);
    border-left: 4px solid var(--primary-color);
}

.hrv-card:hover {
    background: var(--bg-white);
    box-shadow: 0 10px 25px var(--shadow-medium);
    transform: translateX(5px);
}

.hrv-icon {
    width: 60px;
    height: 60px;
    background: var(--primary-color);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    color: var(--bg-white);
    margin-bottom: 1rem;
}

.hrv-card h4 {
    font-size: var(--font-size-xl);
    margin-bottom: 0.75rem;
}

.hrv-card p {
    color: var(--text-medium);
    line-height: 1.7;
}

/* Performance Section */
.performance {
    background: linear-gradient(135deg, #e8e8e8 0%, #d4d4d4 100%);
    color: var(--text-dark);
}

.performance .section-tag {
    background-color: var(--accent-color);
}

.performance .section-title,
.performance .section-subtitle {
    color: var(--text-dark);
}

.performance-features {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-bottom: 4rem;
    flex-wrap: wrap;
}

.feature-highlight {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-dark);
}

.feature-highlight i {
    font-size: var(--font-size-2xl);
    color: var(--accent-color);
}

.platform-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.platform-card {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    padding: 2rem;
    border-radius: var(--radius-lg);
    border: 1px solid rgba(0, 0, 0, 0.1);
    transition: var(--transition-base);
}

.platform-card:hover {
    background: rgba(255, 255, 255, 0.95);
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

.platform-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--accent-color), #93C5FD);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-2xl);
    margin-bottom: 1.5rem;
}

.platform-card h4 {
    font-size: var(--font-size-xl);
    margin-bottom: 1rem;
}

.platform-card p {
    color: var(--text-medium);
    line-height: 1.7;
}

/* Benefits Section */
.benefits-section {
    background: rgba(255, 255, 255, 0.6);
    padding: 3rem;
    border-radius: var(--radius-xl);
    border: 1px solid rgba(0, 0, 0, 0.1);
}

.benefits-title {
    font-size: var(--font-size-2xl);
    text-align: center;
    margin-bottom: 2rem;
}

.benefits-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.benefit-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: var(--font-size-lg);
    color: var(--text-dark);
}

.benefit-item i {
    font-size: var(--font-size-2xl);
    color: var(--primary-color);
}

/* Contact Section */
.contact {
    background-color: var(--bg-light);
}

.contact-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 4rem;
    max-width: 1000px;
    margin: 0 auto;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.form-group label {
    font-weight: 600;
    color: var(--text-dark);
}

.form-group input,
.form-group select,
.form-group textarea {
    padding: 0.875rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: var(--font-primary);
    font-size: var(--font-size-base);
    transition: var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    resize: vertical;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.info-card {
    background: var(--bg-white);
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 15px var(--shadow);
    text-align: center;
}

.info-card i {
    font-size: var(--font-size-3xl);
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.info-card h4 {
    font-size: var(--font-size-xl);
    margin-bottom: 0.5rem;
}

.info-card p {
    color: var(--text-medium);
}

/* Footer */
.footer {
    background: linear-gradient(135deg, #223363 0%, #1a2a4d 100%);
    color: var(--bg-white);
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 2rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: var(--font-size-xl);
    font-weight: 700;
    margin-bottom: 1rem;
}

.footer-logo i {
    font-size: var(--font-size-2xl);
    color: #34C7B5;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.8;
}

.footer-links h4,
.footer-social h4 {
    font-size: var(--font-size-lg);
    margin-bottom: 1rem;
}

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

.footer-links li {
    margin-bottom: 0.75rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: var(--transition-fast);
}

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

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 45px;
    height: 45px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--bg-white);
    font-size: var(--font-size-xl);
    transition: var(--transition-base);
}

.social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.5);
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: var(--bg-white);
    border: none;
    border-radius: var(--radius-full);
    font-size: var(--font-size-xl);
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-base);
    box-shadow: 0 4px 15px var(--shadow-medium);
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-3px);
}

/* Responsive Design */
@media screen and (max-width: 968px) {
    :root {
        --font-size-5xl: 2.5rem;
        --font-size-4xl: 2rem;
        --font-size-3xl: 1.75rem;
    }
    
    .nav-menu {
        position: fixed;
        top: var(--header-height);
        right: -100%;
        width: 70%;
        height: calc(100vh - var(--header-height));
        background-color: var(--bg-white);
        box-shadow: -2px 0 10px var(--shadow);
        padding: 2rem;
        transition: var(--transition-base);
    }
    
    .nav-menu.show {
        right: 0;
    }
    
    .nav-list {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .nav-toggle {
        display: block;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .comparison-grid {
        grid-template-columns: 1fr;
    }
    
    .demo-content {
        grid-template-columns: 1fr;
        gap: 3rem;
    }
    
    .demo-text {
        padding-right: 0;
    }
    
    .devices-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
}

@media screen and (max-width: 576px) {
    :root {
        --font-size-5xl: 2rem;
        --font-size-4xl: 1.75rem;
        --font-size-3xl: 1.5rem;
    }
    
    .hero-buttons {
        flex-direction: column;
    }
    
    .btn {
        width: 100%;
        text-align: center;
    }
    
    .hero-features {
        flex-direction: column;
        gap: 1rem;
    }
    
    .floating-card {
        flex-direction: column;
        text-align: center;
    }
    
    .capabilities-grid,
    .hrv-grid,
    .devices-grid,
    .platform-grid {
        grid-template-columns: 1fr;
    }
    
    .performance-features {
        flex-direction: column;
        gap: 1.5rem;
    }
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }