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

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #10b981;
    --dark: #0f172a;
    --dark-light: #1e293b;
    --gray: #64748b;
    --gray-light: #cbd5e1;
    --white: #ffffff;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    color: var(--dark);
    line-height: 1.6;
    overflow-x: hidden;
    background: #f8fafc;
}

.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(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    z-index: 1000;
    padding: 16px 0;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 700;
    font-size: 20px;
    color: var(--dark);
}

.logo-icon {
    width: 32px;
    height: 32px;
    color: var(--primary);
}

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

.nav-links a {
    color: var(--gray);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s;
}

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

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 12px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 16px;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: white;
    color: var(--dark);
    border: 2px solid var(--gray-light);
}

.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.btn-large {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-icon {
    width: 20px;
    height: 20px;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.hero-content {
    max-width: 600px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary);
    padding: 8px 16px;
    border-radius: 24px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 24px;
}

.badge-icon {
    font-size: 18px;
}

.hero-title {
    font-size: 56px;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    letter-spacing: -0.02em;
}

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

.hero-subtitle {
    font-size: 20px;
    color: var(--gray);
    margin-bottom: 32px;
    line-height: 1.7;
}

.hero-cta {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.stat {
    text-align: center;
}

.stat-value {
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
    margin-bottom: 8px;
}

.stat-label {
    font-size: 14px;
    color: var(--gray);
    font-weight: 500;
}

/* Hero Visual */
.hero-visual {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
}

.phone-mockup {
    position: relative;
    z-index: 2;
}

.phone-frame {
    width: 300px;
    height: 600px;
    background: var(--dark);
    border-radius: 40px;
    padding: 12px;
    box-shadow: var(--shadow-xl);
}

.phone-notch {
    width: 100px;
    height: 24px;
    background: var(--dark);
    margin: 0 auto 8px;
    border-radius: 0 0 16px 16px;
}

.phone-screen {
    width: 100%;
    height: calc(100% - 32px);
    background: white;
    border-radius: 28px;
    overflow: hidden;
}

.app-screenshot {
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: center;
    display: block;
}

/* Fallback styles if image doesn't load */
.screenshot-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    color: white;
}

.screenshot-placeholder span {
    font-size: 64px;
    margin-bottom: 16px;
}

.floating-card {
    position: absolute;
    z-index: 3;
    background: white;
    padding: 16px 20px;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    animation: float 3s ease-in-out infinite;
}

.card-icon {
    font-size: 24px;
}

.card-1 {
    top: 10%;
    left: -10%;
    animation-delay: 0s;
}

.card-2 {
    top: 50%;
    right: -10%;
    animation-delay: 1s;
}

.card-3 {
    bottom: 10%;
    left: -5%;
    animation-delay: 2s;
}

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

/* Section Styles */
section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    max-width: 800px;
    margin: 0 auto 64px;
}

.section-badge {
    display: inline-block;
    background: rgba(99, 102, 241, 0.1);
    color: var(--primary);
    padding: 8px 16px;
    border-radius: 24px;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 16px;
}

.section-title {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 16px;
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 18px;
    color: var(--gray);
    line-height: 1.7;
}

/* Problem Section */
.problem-section {
    background: white;
}

.problem-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.problem-card {
    background: #f8fafc;
    padding: 32px;
    border-radius: 20px;
    border: 2px solid transparent;
    transition: all 0.3s;
}

.problem-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px);
}

.problem-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.problem-card h3 {
    font-size: 24px;
    margin-bottom: 12px;
    font-weight: 700;
}

.problem-card p {
    color: var(--gray);
    margin-bottom: 16px;
}

.problem-stat {
    color: #ef4444;
    font-weight: 700;
    font-size: 18px;
}

/* Science Section */
.science-section {
    background: var(--dark);
    color: white;
}

.science-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.science-section .section-badge {
    background: rgba(255, 255, 255, 0.1);
    color: white;
}

.science-section .section-title {
    color: white;
}

.science-points {
    display: flex;
    flex-direction: column;
    gap: 32px;
    margin-top: 32px;
}

.science-point {
    display: flex;
    gap: 24px;
}

.point-number {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 20px;
}

.point-content h3 {
    font-size: 20px;
    margin-bottom: 8px;
}

.point-content p {
    color: var(--gray-light);
    line-height: 1.7;
}

.science-cite {
    margin-top: 32px;
    padding: 20px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 12px;
    border-left: 4px solid var(--primary);
}

.science-cite p {
    color: var(--gray-light);
    font-size: 14px;
}

/* Brainwave Chart */
.brainwave-chart {
    background: var(--dark-light);
    padding: 32px;
    border-radius: 20px;
    margin-bottom: 24px;
}

.brainwave-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 24px;
}

.brainwave-item {
    display: grid;
    grid-template-columns: 140px 1fr 150px;
    gap: 16px;
    align-items: center;
    margin-bottom: 20px;
}

.wave-label {
    display: flex;
    justify-content: space-between;
}

.wave-name {
    font-weight: 600;
}

.wave-freq {
    color: var(--gray-light);
    font-size: 14px;
}

.wave-bar {
    height: 8px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 4px;
    position: relative;
    overflow: hidden;
}

.wave-bar.active {
    background: rgba(99, 102, 241, 0.3);
}

.wave-effect {
    position: absolute;
    top: 0;
    left: 0;
    height: 100%;
    background: var(--primary);
    border-radius: 4px;
    animation: wave 2s ease-in-out infinite;
}

.wave-bar.active .wave-effect {
    width: 100%;
}

@keyframes wave {
    0%, 100% { transform: translateX(-10%); opacity: 0.8; }
    50% { transform: translateX(10%); opacity: 1; }
}

.wave-desc {
    color: var(--gray-light);
    font-size: 14px;
}

/* Binaural Explanation */
.binaural-explanation {
    background: var(--dark-light);
    padding: 32px;
    border-radius: 20px;
}

.binaural-explanation h4 {
    font-size: 18px;
    margin-bottom: 20px;
}

.binaural-demo {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.ear {
    text-align: center;
}

.ear-icon {
    font-size: 40px;
    margin-bottom: 8px;
}

.frequency {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 4px;
}

.label {
    font-size: 12px;
    color: var(--gray-light);
}

.brain-icon {
    text-align: center;
}

.brain-icon span {
    font-size: 48px;
    display: block;
    margin-bottom: 8px;
}

.perceived-freq {
    font-size: 14px;
    font-weight: 600;
    color: var(--secondary);
}

.binaural-explanation p {
    color: var(--gray-light);
    font-size: 14px;
    line-height: 1.6;
}

/* Features Section - 2-2-3 Layout */
.features-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 24px;
}

/* First row (2 cards): each spans 3 columns (3×2 = 6) */
.feature-card:nth-child(1),
.feature-card:nth-child(2) {
    grid-column: span 3;
}

/* Second row (2 cards): each spans 3 columns (3×2 = 6) */
.feature-card:nth-child(3),
.feature-card:nth-child(4) {
    grid-column: span 3;
}

/* Third row (3 cards): each spans 2 columns (2×3 = 6) - perfectly aligned */
.feature-card:nth-child(5),
.feature-card:nth-child(6),
.feature-card:nth-child(7) {
    grid-column: span 2;
}

/* Responsive: 2 columns on tablets */
@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 24px;
    }

    /* Reset spans on tablets */
    .feature-card {
        grid-column: span 1;
    }
}

.feature-card {
    background: white;
    padding: 32px;
    border-radius: 20px;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-size: 22px;
    margin-bottom: 12px;
    font-weight: 700;
}

.feature-card > p {
    color: var(--gray);
    margin-bottom: 20px;
    line-height: 1.7;
}

.feature-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.feature-list li {
    color: var(--gray);
    font-size: 14px;
    padding-left: 24px;
    position: relative;
}

.feature-list li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--secondary);
    font-weight: 700;
}

/* How It Works */
.how-section {
    background: white;
}

.steps-grid {
    display: grid;
    grid-template-columns: 1fr auto 1fr auto 1fr;
    gap: 32px;
    align-items: center;
}

.step {
    text-align: center;
    padding: 32px;
    background: #f8fafc;
    border-radius: 20px;
}

.step-number {
    width: 64px;
    height: 64px;
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 28px;
    color: white;
    margin: 0 auto 20px;
}

.step h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.step p {
    color: var(--gray);
    line-height: 1.6;
}

.step-arrow {
    font-size: 32px;
    color: var(--primary);
    font-weight: 700;
}

/* Download Section */
.download-section {
    background: var(--primary);
    color: white;
    text-align: center;
}

.download-section .section-badge {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.download-section .section-title {
    color: white;
}

.download-section .section-subtitle {
    color: rgba(255, 255, 255, 0.9);
}

.download-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 40px;
}

.store-button {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 32px;
    background: white;
    color: var(--dark);
    border-radius: 12px;
    text-decoration: none;
    transition: all 0.3s;
    box-shadow: var(--shadow-lg);
}

.store-button:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.store-button.disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.store-button.disabled:hover {
    transform: none;
}

.store-icon {
    width: 40px;
    height: 40px;
}

.store-text {
    text-align: left;
}

.store-label {
    font-size: 11px;
    text-transform: uppercase;
    color: var(--gray);
    font-weight: 500;
}

.store-name {
    font-size: 18px;
    font-weight: 700;
}

.download-note {
    margin-top: 32px;
}

.download-note p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 14px;
}

/* FAQ Section */
.faq-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
}

.faq-item {
    background: white;
    padding: 32px;
    border-radius: 20px;
    box-shadow: var(--shadow);
}

.faq-item h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: var(--dark);
}

.faq-item p {
    color: var(--gray);
    line-height: 1.7;
}

/* CTA Section */
.cta-section {
    background: var(--dark);
    color: white;
    text-align: center;
}

.cta-content h2 {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 16px;
}

.cta-content p {
    font-size: 18px;
    color: var(--gray-light);
    margin-bottom: 32px;
}

/* Footer */
.footer {
    background: var(--dark-light);
    color: white;
    padding: 60px 0 32px;
}

.footer .logo {
    color: white;
}

.footer .logo-icon {
    color: var(--primary);
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 3fr;
    gap: 80px;
    margin-bottom: 40px;
}

.footer-tagline {
    color: var(--gray-light);
    margin-top: 16px;
    line-height: 1.8;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.footer-column h4 {
    margin-bottom: 16px;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-column a {
    display: block;
    color: var(--gray-light);
    text-decoration: none;
    margin-bottom: 12px;
    transition: color 0.3s;
}

.footer-column a:hover {
    color: white;
}

.footer-link-disabled {
    display: block;
    color: #475569;
    margin-bottom: 12px;
    cursor: not-allowed;
    opacity: 0.5;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 32px;
    display: flex;
    justify-content: space-between;
    color: var(--gray-light);
    font-size: 14px;
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--dark);
    padding: 4px 8px;
    border-radius: 8px;
    transition: background 0.2s;
}

.mobile-menu-btn:hover {
    background: rgba(0, 0, 0, 0.05);
}

/* Responsive */
@media (max-width: 968px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-cta {
        justify-content: center;
    }

    .hero-visual {
        margin-top: 60px;
    }

    .floating-card {
        display: none;
    }

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

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

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

    .step-arrow {
        transform: rotate(90deg);
    }

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

    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .mobile-menu-btn {
        display: block;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(10px);
        flex-direction: column;
        padding: 20px 24px;
        box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1);
        gap: 16px;
    }

    .nav-links.mobile-open {
        display: flex;
    }

    .nav-content .btn-primary {
        display: none;
    }
}

@media (max-width: 640px) {
    .hero-title {
        font-size: 36px;
    }

    .section-title {
        font-size: 32px;
    }

    .hero-cta {
        flex-direction: column;
    }

    .download-buttons {
        flex-direction: column;
    }

    .footer-bottom {
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}