/* ============================================================================
   LIFECUE LANDING PAGE - APPLE-INSPIRED MINIMAL DESIGN
   ============================================================================ */

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

/* === DESIGN TOKENS === */
:root {
    /* Colors - 90% grayscale, 10% accent */
    --color-text: #1d1d1f;           /* Apple's near-black */
    --color-text-secondary: #6e6e73;  /* Apple's gray */
    --color-background: #ffffff;
    --color-background-alt: #f5f5f7;  /* Apple's light gray */
    --color-accent: #6366f1;          /* Refined purple */
    --color-dark: #1d1d1f;

    /* Typography - Dramatic scale */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', sans-serif;
    --font-size-hero: 72px;
    --font-size-section: 40px;
    --font-size-large: 24px;
    --font-size-body: 18px;
    --font-size-small: 16px;

    --font-weight-light: 300;
    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;

    /* Spacing - Extreme whitespace */
    --spacing-section: 160px;
    --spacing-container: 120px;
    --spacing-large: 80px;
    --spacing-medium: 48px;
    --spacing-small: 24px;

    /* Layout */
    --max-width: 980px;
    --max-width-narrow: 700px;
}

/* === BASE STYLES === */
html {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-body);
    line-height: 1.6;
    color: var(--color-text);
    background: var(--color-background);
}

/* === NAVIGATION === */
.nav {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 16px 24px;
}

.nav-brand {
    font-size: 20px;
    font-weight: var(--font-weight-semibold);
    color: var(--color-text);
    letter-spacing: -0.02em;
}

/* === HERO SECTION === */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: var(--spacing-section) 24px;
}

.hero-container {
    max-width: var(--max-width);
}

.hero-title {
    font-size: var(--font-size-hero);
    font-weight: var(--font-weight-light);
    line-height: 1.05;
    letter-spacing: -0.015em;
    margin-bottom: var(--spacing-small);
    color: var(--color-text);
}

.hero-subtitle {
    font-size: var(--font-size-large);
    font-weight: var(--font-weight-regular);
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-medium);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-cta {
    margin-top: var(--spacing-medium);
}

/* === SECTIONS === */
.section {
    padding: var(--spacing-section) 24px;
}

.section-gray {
    background: var(--color-background-alt);
}

.section-dark {
    background: var(--color-dark);
    color: white;
}

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

.container-narrow {
    max-width: var(--max-width-narrow);
    margin: 0 auto;
}

.section-title {
    font-size: var(--font-size-section);
    font-weight: var(--font-weight-medium);
    line-height: 1.1;
    letter-spacing: -0.02em;
    text-align: center;
    margin-bottom: var(--spacing-small);
}

.section-lead {
    font-size: var(--font-size-large);
    color: var(--color-text-secondary);
    text-align: center;
    margin-bottom: var(--spacing-large);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* === FEATURES === */
.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-medium);
    margin-top: var(--spacing-large);
}

.feature {
    text-align: center;
}

.feature-title {
    font-size: var(--font-size-large);
    font-weight: var(--font-weight-medium);
    margin-bottom: 12px;
    line-height: 1.2;
}

.feature-text {
    font-size: var(--font-size-body);
    color: var(--color-text-secondary);
    line-height: 1.5;
}

/* === USE CASES === */
.use-cases {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-medium);
    margin-top: var(--spacing-large);
}

.use-case {
    padding: var(--spacing-medium);
    background: white;
    border-radius: 12px;
    text-align: center;
}

.use-case-title {
    font-size: var(--font-size-large);
    font-weight: var(--font-weight-medium);
    margin-bottom: 12px;
}

.use-case-text {
    font-size: var(--font-size-body);
    color: var(--color-text-secondary);
    line-height: 1.5;
}

/* === FOUNDER SECTION === */
.founder-content {
    text-align: center;
    margin-top: var(--spacing-medium);
}

.founder-text {
    font-size: 21px;
    line-height: 1.7;
    color: var(--color-text);
    margin-bottom: var(--spacing-small);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.founder-link {
    margin-top: var(--spacing-medium);
}

.founder-link a {
    font-size: var(--font-size-body);
    color: var(--color-accent);
    text-decoration: none;
    border-bottom: 1px solid rgba(99, 102, 241, 0.3);
    transition: border-color 0.2s;
}

.founder-link a:hover {
    border-bottom-color: var(--color-accent);
}

/* === CONTACT SECTION === */
.contact-title {
    font-size: var(--font-size-section);
    font-weight: var(--font-weight-medium);
    text-align: center;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.contact-subtitle {
    font-size: var(--font-size-large);
    text-align: center;
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: var(--spacing-medium);
}

.contact-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.contact-note {
    margin-top: 24px;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.6);
    text-align: center;
}

/* === BUTTONS === */
.btn-primary {
    display: inline-block;
    padding: 16px 32px;
    background: var(--color-accent);
    color: white;
    text-decoration: none;
    font-size: var(--font-size-body);
    font-weight: var(--font-weight-medium);
    border-radius: 8px;
    transition: all 0.2s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background: #5558e3;
    transform: translateY(-1px);
}

.btn-secondary {
    display: inline-block;
    padding: 16px 32px;
    background: white;
    color: var(--color-text);
    text-decoration: none;
    font-size: var(--font-size-body);
    font-weight: var(--font-weight-medium);
    border-radius: 8px;
    transition: all 0.2s;
}

.btn-secondary:hover {
    background: var(--color-background-alt);
    transform: translateY(-1px);
}

.btn-tertiary {
    display: inline-block;
    padding: 16px 32px;
    background: transparent;
    color: white;
    text-decoration: none;
    font-size: var(--font-size-body);
    font-weight: var(--font-weight-medium);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 8px;
    transition: all 0.2s;
}

.btn-tertiary:hover {
    border-color: white;
    transform: translateY(-1px);
}

/* === FOOTER === */
.footer {
    padding: var(--spacing-medium) 24px;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    text-align: center;
}

.footer-links {
    margin-bottom: 16px;
}

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

.footer-link:hover {
    color: var(--color-text);
}

.footer-separator {
    margin: 0 12px;
    color: var(--color-text-secondary);
    font-size: 14px;
}

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

/* === FOCUS STATES FOR ACCESSIBILITY === */
.btn-primary:focus,
.btn-secondary:focus,
.btn-tertiary:focus,
.nav-brand:focus,
.footer-link:focus,
.founder-link a:focus {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* === RESPONSIVE === */
@media (max-width: 1024px) {
    :root {
        --font-size-hero: 56px;
        --font-size-section: 36px;
        --spacing-section: 120px;
    }
}

@media (max-width: 768px) {
    :root {
        --font-size-hero: 48px;
        --font-size-section: 32px;
        --font-size-large: 21px;
        --font-size-body: 17px;
        --spacing-section: 80px;
        --spacing-container: 64px;
        --spacing-large: 48px;
    }

    .hero {
        min-height: auto;
        padding: var(--spacing-container) 24px;
    }

    .features,
    .use-cases {
        grid-template-columns: 1fr;
        gap: var(--spacing-small);
    }

    .contact-buttons {
        flex-direction: column;
        align-items: stretch;
    }
}

@media (max-width: 480px) {
    :root {
        --font-size-hero: 40px;
        --font-size-section: 28px;
        --spacing-section: 64px;
    }

    .hero-title {
        letter-spacing: -0.01em;
    }
}