:root {
    --bg-color: #0B0B0B;
    --text-primary: #EAEAEA;
    --text-secondary: #A0A0A0;
    --accent-teal: #00C2B2;
    --bg-surface: #121212;
    --bg-card: rgba(28, 28, 30, 0.4);
    --border-color: rgba(255, 255, 255, 0.08);
    --glow-color: rgba(0, 194, 178, 0.4);

    --font-sans: 'Outfit', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 6rem;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-sans);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-sm);
}

@media (min-width: 768px) {
    .container {
        padding: 0 var(--space-md);
    }
}

a {
    color: inherit;
    text-decoration: none;
}

/* Typography */
h1,
h2,
h3,
h4 {
    font-weight: 600;
    line-height: 1.1;
    margin-bottom: var(--space-sm);
}

.text-gradient {
    background: linear-gradient(135deg, #FFFFFF 0%, #A0A0A0 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-md);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.support-line {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

section {
    padding: var(--space-xl) 0;
    position: relative;
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    text-align: center;
    margin-bottom: var(--space-lg);
}

/* Header */
.header {
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 100;
    background: rgba(11, 11, 11, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
}

.header-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo-img {
    height: 65px;
    width: auto;
    object-fit: contain;
    transition: opacity 0.3s;
}

.footer-logo {
    height: 120px;
    opacity: 0.85;
    margin-bottom: 1rem;
}

.logo:hover .logo-img {
    opacity: 0.75;
}

.nav-links {
    display: none;
    align-items: center;
    gap: var(--space-md);
}

@media (min-width: 768px) {
    .nav-links {
        display: flex;
    }
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 0.95rem;
    transition: color 0.3s;
}

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

.lang-switch {
    font-size: 0.85rem !important;
    padding: 0.4rem 0.8rem;
    border: 1px solid var(--border-color);
    border-radius: 999px;
    color: var(--text-primary) !important;
    background: rgba(255, 255, 255, 0.05);
    transition: all 0.3s;
    display: flex;
    align-items: center;
    gap: 6px;
    font-weight: 500;
}

.lang-switch:hover {
    border-color: var(--accent-teal);
    background: rgba(0, 194, 178, 0.05);
}

.lang-flag {
    font-size: 1.1rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 1rem 2.5rem;
    border-radius: 999px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    border: transparent;
    cursor: pointer;
}

.btn-primary {
    background-color: var(--text-primary);
    color: var(--bg-color);
    box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 30px rgba(255, 255, 255, 0.2);
    background-color: #FFFFFF;
}

.btn-secondary {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.05);
    border-color: rgba(255, 255, 255, 0.2);
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    text-align: center;
    padding-top: 100px;
    position: relative;
    overflow: hidden;
    background-color: var(--bg-color);
    background-image: url('/assets/img/hero-bg.png');
    background-size: cover;
    background-position: center bottom;
    background-repeat: no-repeat;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, rgba(11, 11, 11, 0.5) 0%, rgba(11, 11, 11, 0.95) 100%);
    z-index: 0;
}

.hero>.container {
    position: relative;
    z-index: 1;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: var(--space-md);
    margin-bottom: var(--space-md);
}

.hero-stat-pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid var(--border-color);
    padding: 0.5rem 1.2rem;
    border-radius: 999px;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.hero-stat-pill svg {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    color: var(--accent-teal);
}

.hero-stat-pill strong {
    color: var(--text-primary);
}

.hero h1 {
    font-size: clamp(3rem, 7vw, 5.5rem);
    letter-spacing: -0.04em;
    max-width: 900px;
    margin-inline: auto;
    line-height: 1.05;
}

.hero-cta {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    margin-top: var(--space-md);
}

@media (min-width: 640px) {
    .hero-cta {
        flex-direction: row;
        justify-content: center;
    }
}

/* Modes Grid / Binaural Beats Plan Section */
.modes {
    background: var(--bg-surface);
    border-top: 1px solid var(--border-color);
}

.modes-grid {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    max-width: 600px;
    margin: 0 auto;
}

.mode-card {
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 1.5rem;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.mode-card:hover {
    border-color: rgba(0, 194, 178, 0.5);
    background: rgba(0, 194, 178, 0.05);
}

.mode-card.active {
    background: rgba(0, 194, 178, 0.1);
    border-color: var(--accent-teal);
}

.mode-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.mode-icon {
    font-size: 1.8rem;
    background: rgba(255, 255, 255, 0.05);
    width: 48px;
    height: 48px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.mode-card h3 {
    font-size: 1.2rem;
    color: var(--text-primary);
    margin: 0;
}

.mode-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-top: 4px;
}

.play-icon {
    color: var(--accent-teal);
    width: 24px;
    height: 24px;
    opacity: 0.8;
}

.mode-card:hover .play-icon {
    opacity: 1;
}

/* Science Stats Area */
.science-stats {
    text-align: center;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--space-md);
    margin-top: var(--space-md);
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: var(--space-lg) var(--space-md);
    backdrop-filter: blur(10px);
}

.stat-card h3 {
    font-size: 3.5rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-weight: 300;
}

.stat-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* How It Works */
.steps-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-md);
    max-width: 900px;
    margin: 0 auto;
}

.step-card {
    text-align: center;
    background: var(--bg-color);
    border-radius: 16px;
    padding: var(--space-md);
    border: 1px solid var(--border-color);
}

.step-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--accent-teal);
    color: var(--bg-color);
    border-radius: 50%;
    font-size: 1.2rem;
    font-weight: 600;
    margin: 0 auto var(--space-sm);
}

.step-card h3 {
    font-size: 1.3rem;
    color: var(--text-primary);
}

.step-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Testimonials / Quotes */
.testimonials {
    background-color: var(--bg-surface);
    text-align: center;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.stars {
    color: #FFD700;
    font-size: 1.2rem;
    margin-bottom: 1rem;
    letter-spacing: 2px;
}

.review-summary {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: var(--space-lg);
}

.quotes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-md);
}

.quote-card {
    padding: var(--space-lg) var(--space-md);
    background: var(--bg-card);
    border-radius: 16px;
    border: 1px solid var(--border-color);
    text-align: left;
}

.quote-card h4 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.quote-card p {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

/* FAQ Section */
.faq-section {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--border-color);
    padding: 1.5rem 0;
    cursor: pointer;
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1.1rem;
    font-weight: 500;
    color: var(--text-primary);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
    color: var(--text-secondary);
    margin-top: 0;
    line-height: 1.5;
}

.faq-item.active .faq-answer {
    max-height: 200px;
    margin-top: 1rem;
}

.faq-icon {
    font-size: 1.5rem;
    color: var(--text-secondary);
    transition: transform 0.3s;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

/* Final CTA */
.final-cta {
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

/* Footer */
.footer {
    padding: var(--space-md) 0;
    background: var(--bg-color);
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
    text-align: center;
}

.footer-disclaimer {
    color: var(--text-secondary);
    font-size: 0.8rem;
    max-width: 800px;
    margin-bottom: var(--space-sm);
    line-height: 1.5;
}

.footer-links {
    display: flex;
    gap: var(--space-sm);
    font-size: 0.9rem;
    color: var(--text-secondary);
}

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

/* Animations */
.fade-in-up {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-up.visible {
    opacity: 1;
    transform: translateY(0);
}