* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #0071e3;
    --primary-hover: #0077ed;
    --text-dark: #1d1d1f;
    --text-light: #666666;
    --text-link: #06c;
    --bg-primary: #fbfbfd;
    --bg-secondary: #f5f5f7;
    --nav-bg: rgba(255, 255, 255, 0.72);
    --nav-border: rgba(0, 0, 0, 0.04);
    --max-width: 1024px;
    --radius-default: 18px;
    --radius-large: 30px;
    --transition-default: cubic-bezier(0.4, 0, 0.6, 1);
    
    /* Medical Green Color Scheme */
    --medical-green: #34C759;
    --medical-green-light: #4CD964;
    --medical-green-dark: #28A745;
    --medical-green-bg: rgba(52, 199, 89, 0.1);
}

/* Dark theme - system preference */
@media (prefers-color-scheme: dark) {
    :root:not(.theme-light) {
        --text-dark: #f5f5f7;
        --text-light: #a1a1a6;
        --text-link: #2997ff;
        --bg-primary: #000000;
        --bg-secondary: #1d1d1f;
        --nav-bg: rgba(29, 29, 31, 0.72);
        --nav-border: rgba(255, 255, 255, 0.1);
    }
}

/* Manual dark theme override */
:root.theme-dark {
    --text-dark: #f5f5f7;
    --text-light: #a1a1a6;
    --text-link: #2997ff;
    --bg-primary: #000000;
    --bg-secondary: #1d1d1f;
    --nav-bg: rgba(29, 29, 31, 0.72);
    --nav-border: rgba(255, 255, 255, 0.1);
}

@supports (backdrop-filter: blur(20px)) {
    :root {
        --nav-bg: rgba(255, 255, 255, 0.72);
    }
    
    @media (prefers-color-scheme: dark) {
        :root:not(.theme-light) {
            --nav-bg: rgba(29, 29, 31, 0.72);
        }
    }
    
    :root.theme-dark {
        --nav-bg: rgba(29, 29, 31, 0.72);
    }
    
    :root.theme-light {
        --nav-bg: rgba(255, 255, 255, 0.72);
    }
}

@font-face {
    font-family: "SF Pro Display";
    src: local("-apple-system"), local("BlinkMacSystemFont");
}

html {
    font-size: 17px;
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", Helvetica, Arial, sans-serif;
    font-synthesis: none;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    color: var(--text-dark);
    line-height: 1.47059;
    letter-spacing: -0.022em;
    background-color: var(--bg-primary);
    transition: background-color 0.3s var(--transition-default), 
                color 0.3s var(--transition-default);
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 22px;
}

/* Navigation */
.nav-wrapper {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 9999;
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
}

.nav-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 100%;
    background-color: var(--nav-bg);
    border-bottom: 0.5px solid var(--nav-border);
    transition: background-color 0.3s var(--transition-default), 
                border-color 0.3s var(--transition-default);
}

nav {
    position: relative;
    height: 48px;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 22px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

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

.nav-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 21px;
    font-weight: 600;
    color: var(--text-dark);
    text-decoration: none;
    letter-spacing: 0.231em;
}

.nav-logo img {
    width: 32px;
    height: 32px;
    filter: brightness(0) saturate(100%) invert(13%) sepia(7%) saturate(966%) hue-rotate(314deg) brightness(94%) contrast(94%);
    transition: filter 0.3s var(--transition-default);
}

@media (prefers-color-scheme: dark) {
    :root:not(.theme-light) .nav-logo img {
        filter: brightness(0) saturate(100%) invert(100%);
    }
}

:root.theme-dark .nav-logo img {
    filter: brightness(0) saturate(100%) invert(100%);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 40px;
    list-style: none;
}

.nav-menu a {
    font-size: 12px;
    color: var(--text-dark);
    text-decoration: none;
    opacity: 0.8;
    transition: opacity 0.3s var(--transition-default);
}

.nav-menu a:hover,
.nav-menu a:focus {
    opacity: 1;
    outline: none;
}

.nav-menu a:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
    border-radius: 4px;
}

.mobile-menu-toggle {
    display: none;
}

.mobile-menu-toggle:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* Theme Toggle */
.theme-toggle {
    background: none;
    border: none;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 16px;
    opacity: 0.8;
    transition: opacity 0.3s var(--transition-default), 
                background-color 0.3s var(--transition-default);
}

.theme-toggle:hover {
    opacity: 1;
    background-color: rgba(0, 0, 0, 0.05);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

@media (prefers-color-scheme: dark) {
    .theme-toggle:hover {
        background-color: rgba(255, 255, 255, 0.1);
    }
}

/* Hero Section */
.hero {
    padding-top: 48px;
    background-color: var(--bg-primary);
}

.hero-content {
    padding: 110px 0 60px;
    text-align: center;
}

.hero-headline {
    font-size: 56px;
    line-height: 1.07143;
    font-weight: 600;
    letter-spacing: -0.005em;
    margin-bottom: 6px;
    background: linear-gradient(180deg, #1d1d1f 0%, #86868b 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subheadline {
    font-size: 28px;
    line-height: 1.10722;
    font-weight: 400;
    letter-spacing: 0.004em;
    color: var(--text-dark);
    margin-bottom: 20px;
}

.hero-copy {
    font-size: 21px;
    line-height: 1.381;
    font-weight: 400;
    color: var(--text-light);
    margin-bottom: 40px;
    max-width: 730px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 21px;
    line-height: 1.381;
    color: var(--text-link);
    text-decoration: none;
}

.hero-cta:hover,
.hero-cta:focus {
    text-decoration: underline;
    outline: none;
}

.hero-cta:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
    border-radius: 4px;
}

.hero-cta::after {
    content: "›";
    font-size: 24px;
}

/* Device Frame */
.device-frame {
    margin: 80px auto 0;
    max-width: 1000px;
    position: relative;
}

.device-chrome {
    position: relative;
    background: var(--bg-secondary);
    border-radius: var(--radius-large);
    padding: 10px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s var(--transition-default);
}

.device-screen {
    background: #000;
    border-radius: var(--radius-default);
    aspect-ratio: 16 / 10;
    overflow: hidden;
    position: relative;
}

.device-menubar {
    position: absolute;
    left: 0;
    right: 0;
    height: 24px;
    background: rgba(255, 255, 255, 0.95);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 10px;
    font-size: 12px;
    color: #000;
}

@media (prefers-color-scheme: dark) {
    .device-menubar {
        background: rgba(30, 30, 30, 0.95);
        color: #fff;
    }
}

.menubar-left {
    display: flex;
    gap: 15px;
    font-weight: 600;
}

.menubar-right {
    display: flex;
    align-items: center;
    gap: 15px;
}

.glucose-widget {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 2px 6px;
    color: #fff;
    font-weight: 500;
}

.device-content {
    position: absolute;
    top: 24px;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('images/menubar_background.png');
    background-size: cover;
    background-position: center;
}

.menubar-dropdown {
    position: absolute;
    top: 24px;
    right: 0;
    width: 280px;
    height: auto;
    background-image: url('images/menubar_app_opened.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: top center;
    aspect-ratio: 280/200;
    z-index: 10;
}

/* Feature Showcase */
.feature-showcase {
    padding: 120px 0;
    background-color: var(--bg-secondary);
}

.showcase-header {
    text-align: center;
    margin-bottom: 80px;
}

.showcase-eyebrow {
    font-size: 21px;
    line-height: 1.381;
    color: var(--text-light);
    margin-bottom: 10px;
}

.showcase-headline {
    font-size: 48px;
    line-height: 1.08349;
    font-weight: 600;
    letter-spacing: -0.003em;
    color: var(--text-dark);
}

.showcase-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.showcase-item {
    background: var(--bg-primary);
    border-radius: var(--radius-default);
    overflow: hidden;
    transition: transform 0.3s var(--transition-default);
}

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

.showcase-image {
    width: 100%;
    height: 300px;
    object-fit: cover;
}

.dark-mode-img {
    display: none;
}

@media (prefers-color-scheme: dark) {
    :root:not(.theme-light) .light-mode-img {
        display: none;
    }
    
    :root:not(.theme-light) .dark-mode-img {
        display: block;
    }
}

:root.theme-dark .light-mode-img {
    display: none;
}

:root.theme-dark .dark-mode-img {
    display: block;
}

.showcase-content {
    padding: 40px;
}

.showcase-title {
    font-size: 24px;
    line-height: 1.16667;
    font-weight: 600;
    margin-bottom: 10px;
}

.showcase-description {
    font-size: 17px;
    line-height: 1.47059;
    color: var(--text-light);
}


}

/* Features Section */
.features {
    padding: 120px 0;
    background-color: var(--bg-primary);
}

.features-header {
    text-align: center;
    margin-bottom: 80px;
}

.features-headline {
    font-size: 48px;
    line-height: 1.08349;
    font-weight: 600;
    letter-spacing: -0.003em;
    margin-bottom: 20px;
}

.features-subheadline {
    font-size: 21px;
    line-height: 1.381;
    color: var(--text-light);
    max-width: 650px;
    margin: 0 auto;
}

.features-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 60px 30px;
}

.feature-item {
    text-align: center;
}

.feature-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
}

.feature-name {
    font-size: 21px;
    line-height: 1.381;
    font-weight: 600;
    margin-bottom: 10px;
}

.feature-description {
    font-size: 17px;
    line-height: 1.47059;
    color: var(--text-light);
}

/* Privacy Section */
.privacy-section {
    padding: 120px 0;
    background-color: var(--bg-secondary);
}

.privacy-header {
    text-align: center;
    margin-bottom: 60px;
}

.privacy-icon {
    width: 88px;
    height: 88px;
    margin: 0 auto 30px;
    background: linear-gradient(180deg, #64d2ff 0%, #0051d5 100%);
    border-radius: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.privacy-icon::before {
    content: "🔒";
    font-size: 48px;
}

.privacy-headline {
    font-size: 48px;
    line-height: 1.08349;
    font-weight: 600;
    letter-spacing: -0.003em;
    margin-bottom: 20px;
}

.privacy-subheadline {
    font-size: 21px;
    line-height: 1.381;
    color: var(--text-light);
    max-width: 650px;
    margin: 0 auto;
}

.privacy-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.privacy-feature {
    display: flex;
    gap: 20px;
}

.privacy-feature-icon {
    flex-shrink: 0;
    width: 44px;
    height: 44px;
    background: var(--bg-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.privacy-feature-content h3 {
    font-size: 19px;
    line-height: 1.21053;
    font-weight: 600;
    margin-bottom: 8px;
}

.privacy-feature-content p {
    font-size: 17px;
    line-height: 1.47059;
    color: var(--text-light);
}

/* CTA Section */
.cta-section {
    padding: 120px 0;
    background-color: var(--bg-primary);
    text-align: center;
}

.cta-headline {
    font-size: 48px;
    line-height: 1.08349;
    font-weight: 600;
    letter-spacing: -0.003em;
    margin-bottom: 30px;
}

.cta-button {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 12px 30px;
    border-radius: 980px;
    font-size: 17px;
    line-height: 1.17648;
    font-weight: 400;
    text-decoration: none;
    transition: background-color 0.15s var(--transition-default);
}

.cta-button:hover,
.cta-button:focus {
    background: var(--primary-hover);
    outline: none;
}

.cta-button:focus-visible {
    outline: 2px solid white;
    outline-offset: 2px;
}

.cta-caption {
    margin-top: 20px;
    font-size: 14px;
    line-height: 1.42859;
    color: var(--text-light);
}

/* Footer */
footer {
    background-color: var(--bg-secondary);
    padding: 40px 0 80px;
    font-size: 12px;
    line-height: 1.33337;
    color: var(--text-light);
}

.footer-content {
    padding-top: 20px;
    border-top: 1px solid #d2d2d7;
}

.footer-links {
    display: flex;
    gap: 30px;
    margin-bottom: 20px;
}

.footer-links a {
    color: var(--text-dark);
    text-decoration: none;
}

.footer-links a:hover,
.footer-links a:focus {
    text-decoration: underline;
    outline: none;
}

.footer-links a:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
    border-radius: 4px;
}

.footer-legal {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

/* Responsive */
@media (max-width: 1068px) {
    .hero-headline {
        font-size: 48px;
    }
    
    .hero-subheadline {
        font-size: 24px;
    }
    
    .showcase-grid {
        grid-template-columns: 1fr;
    }
    
    .features-list {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 734px) {
    html, body {
        overflow-x: hidden;
        max-width: 100vw;
    }
    
    * {
        max-width: 100%;
        box-sizing: border-box;
    }
    
    .container {
        padding: 0 16px;
        max-width: 100vw;
    }
    
    .nav-menu {
        position: absolute;
        top: 100%;
        left: 16px;
        right: 16px;
        background: rgba(255, 255, 255, 0.95);
        backdrop-filter: saturate(180%) blur(20px);
        -webkit-backdrop-filter: saturate(180%) blur(20px);
        flex-direction: column;
        padding: 0 20px;
        gap: 20px;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: transform 0.3s var(--transition-default), 
                    opacity 0.3s var(--transition-default),
                    visibility 0.3s var(--transition-default),
                    background-color 0.3s var(--transition-default),
                    border-color 0.3s var(--transition-default);
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
        border-bottom: 1px solid rgba(0, 0, 0, 0.1);
        z-index: -1;
        border-radius: 12px;
    }
    
    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
        padding: 20px;
    }
    
    .mobile-menu-toggle {
        display: block;
        background: none;
        border: none;
        width: 48px;
        height: 48px;
        cursor: pointer;
        position: relative;
    }
    
    .mobile-menu-toggle span {
        position: absolute;
        left: 16px;
        height: 1px;
        background: var(--text-dark);
        transition: all 0.3s var(--transition-default);
    }
    
    .mobile-menu-toggle span:first-child {
        top: 19px;
        width: 16px;
    }
    
    .mobile-menu-toggle span:last-child {
        bottom: 19px;
        width: 16px;
    }
    
    .hero {
        padding-top: 28px;
    }
    
    .hero-content {
        padding: 60px 0 40px;
    }
    
    .hero-headline {
        font-size: 32px;
    }
    
    .hero-subheadline {
        font-size: 19px;
    }
    
    .hero-copy {
        font-size: 17px;
    }
    
    .feature-showcase,
    .features,
    .privacy-section,
    .cta-section {
        padding: 60px 0;
    }
    
    .features-list {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .privacy-features {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .device-frame {
        margin: 40px auto 0;
        max-width: calc(100vw - 32px);
        transform: scale(0.7);
        transform-origin: center top;
    }
    
    .menubar-dropdown {
        width: 140px;
        right: 35px;
        top: 20px;
        aspect-ratio: 140/98;
    }
    
    /* Legal pages responsive styles */
    .legal-content h1,
    .support-content h1,
    .contact-content h1 {
        font-size: 32px !important;
        line-height: 1.125 !important;
        margin-bottom: 24px !important;
    }
    
    .legal-content h2,
    .support-content h2,
    .contact-content h2 {
        font-size: 24px !important;
        line-height: 1.16667 !important;
        margin-top: 40px !important;
        margin-bottom: 16px !important;
    }
    
    .legal-content,
    .support-content,
    .contact-content {
        padding: 80px 16px 60px !important;
    }
    
    .faq-question {
        padding: 16px !important;
        font-size: 16px !important;
    }
    
    .faq-answer {
        padding: 0 16px !important;
    }
    
    .faq-item.active .faq-answer {
        padding: 0 16px 16px !important;
    }
    
    .contact-section {
        padding: 24px !important;
        margin-top: 40px !important;
    }
    
    .contact-button {
        padding: 14px 24px !important;
        font-size: 16px !important;
        margin-top: 16px !important;
    }
    
    /* Dark mode styles for mobile menu */
    @media (prefers-color-scheme: dark) {
        :root:not(.theme-light) .nav-menu {
            background: rgba(29, 29, 31, 0.95);
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
            border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        }
    }
    
    :root.theme-dark .nav-menu {
        background: rgba(29, 29, 31, 0.95);
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }
}

/* Extra small screens (phones under 375px) */
@media (max-width: 374px) {
    .legal-content h1,
    .support-content h1,
    .contact-content h1 {
        font-size: 28px !important;
        margin-bottom: 20px !important;
    }
    
    .legal-content,
    .support-content,
    .contact-content {
        padding: 60px 12px 40px !important;
    }
    
    .hero-headline {
        font-size: 36px !important;
    }
    
    .hero-subheadline {
        font-size: 19px !important;
    }
}

/* Reduced Motion Preference */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}