/* ==========================================================================
   Neura Stream Switcher (NSS) Landing Page Stylesheet
   Theme: Dark Modern Gaming / Creator Accent
   ========================================================================== */

:root {
    --bg-primary: #0b0f17;
    --bg-secondary: #131b2e;
    --bg-card: #1a233a;
    --bg-card-hover: #222d4a;
    
    --accent-emerald: #10b981;
    --accent-emerald-glow: rgba(16, 185, 129, 0.25);
    --accent-cyan: #06b6d4;
    --accent-rose: #f43f5e;
    --accent-purple: #c084fc;
    
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --border-color: rgba(255, 255, 255, 0.08);
    --border-highlight: rgba(16, 185, 129, 0.3);
    
    --font-sans: 'Inter', 'Noto Sans JP', -apple-system, BlinkMacSystemFont, sans-serif;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    
    --max-width: 1200px;
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

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

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

img, video {
    max-width: 100%;
    height: auto;
    display: block;
}

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

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

.text-gradient {
    background: linear-gradient(135deg, var(--accent-emerald) 0%, var(--accent-cyan) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Header Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 100;
    background: rgba(11, 15, 23, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.brand-logo {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.logo-accent {
    color: var(--accent-emerald);
}

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

.nav-links a {
    font-size: 0.95rem;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color var(--transition-fast);
}

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

/* Buttons & Badges */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-weight: 700;
    border-radius: var(--radius-md);
    transition: all var(--transition-normal);
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
    color: #ffffff;
    box-shadow: 0 4px 20px var(--accent-emerald-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(16, 185, 129, 0.4);
}

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

.btn-secondary:hover {
    background: var(--bg-card-hover);
    border-color: var(--text-secondary);
}

.btn-sm { padding: 8px 16px; font-size: 0.875rem; }
.btn-lg { padding: 14px 28px; font-size: 1rem; }
.btn-xl { 
    padding: 18px 36px; 
    font-size: 1.125rem; 
    flex-direction: column;
    border-radius: var(--radius-lg);
}

.btn-xl small {
    font-size: 0.8rem;
    font-weight: 400;
    opacity: 0.85;
}

.icon { width: 20px; height: 20px; }
.icon-lg { width: 28px; height: 28px; }

.badge {
    display: inline-block;
    padding: 6px 14px;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--accent-emerald);
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: 50px;
    margin-bottom: 16px;
}

.badge-accent {
    color: var(--accent-cyan);
    background: rgba(6, 182, 212, 0.1);
    border-color: rgba(6, 182, 212, 0.2);
}

/* Hero Section */
.hero-section {
    padding: 160px 0 100px 0;
    background: radial-gradient(circle at 50% 20%, rgba(16, 185, 129, 0.12) 0%, transparent 60%);
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-title {
    font-size: 3rem;
    line-height: 1.25;
    font-weight: 800;
    margin-bottom: 20px;
    letter-spacing: -0.03em;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 36px;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.app-frame-wrapper {
    position: relative;
    border-radius: var(--radius-lg);
    padding: 12px;
    background: var(--bg-card);
    border: 1px solid var(--border-highlight);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
}

.app-screenshot {
    width: 100%;
    border-radius: var(--radius-md);
    object-fit: cover;
}

/* Placeholder Tag Styling */
.placeholder-tag {
    display: none;
    margin-top: 10px;
    padding: 10px;
    background: rgba(0, 0, 0, 0.6);
    border: 1px dashed var(--accent-emerald);
    border-radius: var(--radius-sm);
    text-align: center;
    color: var(--accent-emerald);
    font-size: 0.85rem;
    font-family: monospace;
}

.placeholder-tag.show {
    display: block;
}

.placeholder-tag small {
    display: block;
    color: var(--text-secondary);
    margin-top: 4px;
}

/* Core Features Section */
.features-section {
    padding: 120px 0;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

/* Demo Video Section */
.demo-section {
    padding: 100px 0;
}

.section-header {
    margin-bottom: 50px;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 800;
    margin-bottom: 12px;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
}

.demo-video-wrapper {
    position: relative;
    max-width: 900px;
    margin: 0 auto;
    border-radius: var(--radius-lg);
    overflow: hidden;
    border: 1px solid var(--border-color);
    background: #000000;
    box-shadow: 0 15px 40px rgba(0,0,0,0.5);
}

.demo-video {
    width: 100%;
    display: block;
}

.sound-toggle-btn {
    position: absolute;
    bottom: 16px;
    right: 16px;
    z-index: 10;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    background: rgba(11, 15, 23, 0.85);
    backdrop-filter: blur(8px);
    color: var(--text-primary);
    border: 1px solid var(--border-highlight);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.sound-toggle-btn:hover {
    background: rgba(16, 185, 129, 0.25);
    border-color: var(--accent-emerald);
    transform: translateY(-2px);
}

.sound-toggle-btn.is-active {
    background: rgba(16, 185, 129, 0.9);
    color: #ffffff;
    border-color: var(--accent-emerald);
}

.demo-note {
    margin-top: 16px;
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-muted);
}

.feature-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    margin-bottom: 100px;
}

.feature-row.reverse {
    grid-template-columns: 1fr 1fr;
}

.feature-row.reverse .feature-text {
    order: 2;
}

.feature-row.reverse .feature-media {
    order: 1;
}

.feature-icon-badge {
    font-size: 1rem;
    font-weight: 800;
    color: var(--accent-emerald);
    margin-bottom: 12px;
    font-family: monospace;
}

.feature-heading {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 16px;
}

.feature-description {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.feature-media {
    background: var(--bg-card);
    padding: 12px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.feature-img {
    width: 100%;
    border-radius: var(--radius-sm);
}

/* 3 Slots Section */
.slots-section {
    padding: 100px 0;
    background: var(--bg-secondary);
}

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

.slot-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    display: flex;
    flex-direction: column;
    transition: transform var(--transition-normal), border-color var(--transition-normal);
}

.slot-card:hover {
    transform: translateY(-6px);
    border-color: var(--accent-emerald);
}

.slot-tag {
    font-size: 0.75rem;
    font-weight: 800;
    color: var(--accent-cyan);
    letter-spacing: 0.05em;
    margin-bottom: 8px;
    display: block;
}

.slot-card h3 {
    font-size: 1.35rem;
    margin-bottom: 12px;
}

.slot-card-desc {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
    flex-grow: 1;
}

.slot-media {
    border-radius: var(--radius-sm);
    overflow: hidden;
    background: #000;
}

.slot-img {
    width: 100%;
}

/* Download Section */
.download-section {
    padding: 120px 0;
    background: radial-gradient(circle at 50% 50%, rgba(16, 185, 129, 0.15) 0%, transparent 70%);
}

.download-box {
    max-width: 800px;
    margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid var(--border-highlight);
    border-radius: var(--radius-lg);
    padding: 60px 40px;
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.5);
}

.download-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 12px;
}

.download-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 40px;
}

.download-cta-wrapper {
    margin-bottom: 40px;
}

.specs-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    text-align: left;
    background: rgba(0,0,0,0.3);
    padding: 24px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
}

.spec-item {
    display: flex;
    flex-direction: column;
}

.spec-label {
    font-size: 0.8rem;
    color: var(--text-muted);
}

.spec-value {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* Footer */
.footer {
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
    background: var(--bg-primary);
    font-size: 0.9rem;
    color: var(--text-secondary);
}

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

.footer-logo {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.footer-links {
    display: flex;
    gap: 24px;
}

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

/* Animations */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

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

.delay-100 { transition-delay: 0.1s; }
.delay-200 { transition-delay: 0.2s; }

/* Responsive Media Queries */
@media (max-width: 992px) {
    .hero-container, .feature-row, .feature-row.reverse {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .feature-row.reverse .feature-text { order: 1; }
    .feature-row.reverse .feature-media { order: 2; }
    
    .slots-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-title { font-size: 2.25rem; }
    .specs-grid { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
    .nav-links { display: none; }
    .footer-container { flex-direction: column; gap: 20px; text-align: center; }
}
/* ==========================================================================
   Download Options Card Styles
   ========================================================================== */

.download-box {
    max-width: 960px;
}

.download-options-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-bottom: 40px;
    text-align: left;
}

.download-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 28px 24px;
    display: flex;
    flex-direction: column;
    position: relative;
    transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.download-card:hover {
    transform: translateY(-4px);
    border-color: rgba(255, 255, 255, 0.2);
}

.download-card.highlight-card {
    border-color: var(--border-highlight);
    background: linear-gradient(180deg, rgba(16, 185, 129, 0.05) 0%, var(--bg-secondary) 100%);
}

.download-card.highlight-card:hover {
    border-color: var(--accent-emerald);
}

.download-card-badge {
    display: inline-block;
    align-self: flex-start;
    padding: 4px 10px;
    font-size: 0.75rem;
    font-weight: 700;
    border-radius: 4px;
    margin-bottom: 12px;
}

.badge-store {
    background: rgba(16, 185, 129, 0.15);
    color: var(--accent-emerald);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.badge-portable {
    background: rgba(6, 182, 212, 0.15);
    color: var(--accent-cyan);
    border: 1px solid rgba(6, 182, 212, 0.3);
}

.download-card-title {
    font-size: 1.35rem;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.download-card-desc {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.download-merits {
    list-style: none;
    padding: 0;
    margin: 0 0 24px 0;
    flex-grow: 1;
}

.download-merits li {
    font-size: 0.88rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    line-height: 1.5;
    display: flex;
    align-items: flex-start;
    gap: 8px;
}

.merit-icon {
    color: var(--accent-emerald);
    font-weight: bold;
    flex-shrink: 0;
}

.download-info-box {
    border-radius: var(--radius-sm);
    padding: 12px 14px;
    margin-bottom: 20px;
    font-size: 0.82rem;
    line-height: 1.5;
    color: var(--text-secondary);
    min-height: 105px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.download-info-box strong {
    display: block;
    margin-bottom: 4px;
    font-size: 0.85rem;
}

.download-info-box p {
    margin: 0;
}

.download-info-box b {
    color: var(--text-primary);
}

.box-store {
    background: rgba(16, 185, 129, 0.08);
    border: 1px solid rgba(16, 185, 129, 0.25);
}

.box-store strong {
    color: var(--accent-emerald);
}

.box-warning {
    background: rgba(245, 158, 11, 0.08);
    border: 1px solid rgba(245, 158, 11, 0.3);
}

.box-warning strong {
    color: #f59e0b;
}

.btn-card-action {
    width: 100%;
    padding: 12px 16px;
    font-size: 0.95rem;
}

.download-note {
    display: block;
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 10px;
}

@media (max-width: 820px) {
    .download-options-grid {
        grid-template-columns: 1fr;
    }
    .download-info-box {
        min-height: auto;
    }
}