/* ============================================
   YiScanner Official Website - Style Guide
   Color Palette:
     --bg-primary: #070d1a (deepest navy)
     --bg-secondary: #0a1628 (deep navy)
     --bg-tertiary: #111d35 (navy)
     --accent: #00d4ff (cyan)
     --accent-light: #4da6ff (sky blue)
     --accent-glow: rgba(0, 212, 255, 0.15)
     --text-primary: #ffffff
     --text-secondary: rgba(255,255,255,0.7)
     --text-muted: rgba(255,255,255,0.45)
   ============================================ */

/* ---- CSS Custom Properties ---- */
:root {
    --bg-primary: #070d1a;
    --bg-secondary: #0a1628;
    --bg-card: #0f1b33;
    --bg-card-hover: #132747;
    --accent: #00d4ff;
    --accent-light: #4da6ff;
    --accent-dark: #0099cc;
    --accent-glow: rgba(0, 212, 255, 0.12);
    --accent-glow-strong: rgba(0, 212, 255, 0.25);
    --gradient-main: linear-gradient(135deg, #00d4ff 0%, #4da6ff 50%, #0099cc 100%);
    --gradient-bg: linear-gradient(180deg, #070d1a 0%, #0a1628 40%, #0f1e38 100%);
    --gradient-hero: radial-gradient(ellipse at 50% 0%, #112a4a 0%, #070d1a 70%);
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.75);
    --text-muted: rgba(255, 255, 255, 0.45);
    --border-color: rgba(255, 255, 255, 0.08);
    --border-accent: rgba(0, 212, 255, 0.2);
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --shadow-glow: 0 0 40px rgba(0, 212, 255, 0.15);
    --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);
    --font-sans: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', sans-serif;
    --transition-fast: 0.2s ease;
    --transition-smooth: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --transition-bounce: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* ---- Reset & Base ---- */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; font-size: 16px; }
body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}
a { text-decoration: none; color: inherit; transition: color var(--transition-fast); }
a:hover { color: var(--accent); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }
.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
.section { padding: 100px 0; position: relative; }

/* ---- Utility Classes ---- */
.gradient-text {
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ============================================
   NAVBAR
   ============================================ */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    padding: 16px 0;
    transition: all var(--transition-smooth);
    backdrop-filter: blur(0px);
    background: transparent;
}
.navbar.scrolled {
    padding: 10px 0;
    background: rgba(7, 13, 26, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}
.nav-container {
    max-width: 1200px; margin: 0 auto; padding: 0 24px;
    display: flex; align-items: center; justify-content: space-between;
}
.nav-logo {
    display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px;
}
.logo-img { width: 36px; height: 36px; border-radius: 10px; }
.nav-links {
    display: flex; gap: 32px;
}
.nav-links a {
    font-size: 14px; font-weight: 500; color: var(--text-secondary);
    position: relative; padding: 4px 0;
}
.nav-links a::after {
    content: ''; position: absolute; bottom: -2px; left: 0; width: 0; height: 2px;
    background: var(--accent); border-radius: 1px;
    transition: width var(--transition-smooth);
}
.nav-links a:hover { color: var(--text-primary); }
.nav-links a:hover::after { width: 100%; }

.nav-download-btn {
    display: inline-flex; align-items: center; gap: 6px;
    padding: 8px 18px; background: var(--accent-glow);
    border: 1px solid var(--border-accent); border-radius: 50px;
    font-size: 13px; font-weight: 600; color: var(--accent);
    transition: all var(--transition-smooth);
}
.nav-download-btn:hover {
    background: var(--accent); color: var(--bg-primary);
    transform: translateY(-1px); box-shadow: var(--shadow-glow);
}

.mobile-menu-btn { display: none; cursor: pointer; flex-direction: column; gap: 5px; background: none; border: none; padding: 4px; }
.mobile-menu-btn span { display: block; width: 24px; height: 2px; background: var(--text-primary); border-radius: 2px; transition: all var(--transition-smooth); }

/* ============================================
   HERO SECTION
   ============================================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    background: var(--gradient-hero);
}

/* Grid Background */
.hero-bg-grid {
    position: absolute; inset: 0;
    background-image:
        linear-gradient(rgba(0, 212, 255, 0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 212, 255, 0.04) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 30%, transparent 75%);
    animation: gridMove 20s linear infinite;
}
@keyframes gridMove {
    0% { transform: translate(0, 0); }
    100% { transform: translate(60px, 60px); }
}

/* Particles */
.hero-particles { position: absolute; inset: 0; pointer-events: none; }
.particle {
    position: absolute; width: 3px; height: 3px;
    background: var(--accent); border-radius: 50%;
    opacity: 0; animation: particleFloat 6s ease-in-out infinite;
}
@keyframes particleFloat {
    0%   { opacity: 0; transform: translateY(0) scale(0); }
    20%  { opacity: 0.6; transform: translateY(-30vh) scale(1); }
    80%  { opacity: 0.3; transform: translateY(-70vh) scale(0.5); }
    100% { opacity: 0; transform: translateY(-100vh) scale(0); }
}

/* Light Rays */
.light-ray {
    position: absolute; width: 400px; height: 600px;
    background: linear-gradient(180deg, rgba(0, 212, 255, 0.08), transparent);
    filter: blur(60px);
    animation: rayFloat 8s ease-in-out infinite alternate;
}
.light-ray-1 { left: 10%; top: -10%; animation-delay: 0s; }
.light-ray-2 { right: 20%; top: 5%; animation-delay: 3s; width: 300px; }
.light-ray-3 { right: -5%; top: -5%; animation-delay: 5s; opacity: 0.5; }
@keyframes rayFloat {
    from { transform: translateX(-30px) rotate(-5deg); }
    to   { transform: translateX(30px) rotate(5deg); }
}

/* Hero Content */
.hero-content {
    text-align: center; z-index: 2;
    max-width: 720px; padding: 0 24px;
    margin: 0 auto;
}
.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 6px 18px; background: rgba(0, 212, 255, 0.08);
    border: 1px solid var(--border-accent); border-radius: 50px;
    font-size: 13px; font-weight: 500; color: var(--accent-light);
    margin-bottom: 28px;
}
.badge-dot {
    width: 6px; height: 6px; border-radius: 50%;
    background: var(--accent);
    animation: dotPulse 2s ease-in-out infinite;
}
@keyframes dotPulse {
    0%, 100% { opacity: 1; box-shadow: 0 0 0 0 rgba(0,212,255,0.5); }
    50%      { opacity: .7; box-shadow: 0 0 0 6px rgba(0,212,255,0); }
}

.hero-title {
    font-size: clamp(36px, 6vw, 60px);
    font-weight: 800; line-height: 1.15;
    letter-spacing: -0.5px; margin-bottom: 20px;
    white-space: nowrap;
}

.hero-subtitle {
    font-size: clamp(17px, 2.5vw, 22px);
    font-weight: 500; color: var(--accent-light);
    letter-spacing: 1px; margin-bottom: 14px;
}
.hero-desc {
    font-size: 16px; color: var(--text-secondary); line-height: 1.8; margin-bottom: 36px;
}

/* Buttons */
.btn {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 14px 30px; border-radius: 50px; font-weight: 600; font-size: 15px;
    cursor: pointer; border: none; transition: all var(--transition-smooth);
}
.btn-primary {
    background: var(--gradient-main);
    color: #fff; box-shadow: 0 4px 24px rgba(0, 212, 255, 0.25);
}
.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 40px rgba(0, 212, 255, 0.4);
}
.btn-glow { animation: btnGlow 3s ease-in-out infinite alternate; }
@keyframes btnGlow {
    from { box-shadow: 0 4px 24px rgba(0, 212, 255, 0.25); }
    to   { box-shadow: 0 4px 40px rgba(0, 212, 255, 0.45), 0 0 80px rgba(0, 212, 255, 0.15); }
}
.btn-secondary {
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}
.btn-secondary:hover {
    border-color: var(--border-accent);
    color: var(--text-primary);
    background: rgba(0, 212, 255, 0.05);
}
.hero-actions { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* Hero Visual - Phone Mockups */
.hero-visual {
    position: absolute; right: 4%; top: 50%; transform: translateY(-50%);
    z-index: 2; pointer-events: none;
}
.phone-mockup {
    position: absolute;
    width: 240px;
    border-radius: 36px;
    background: #1a1a2e;
    padding: 10px;
    box-shadow:
        0 30px 80px rgba(0, 0, 0, 0.5),
        inset 0 0 0 1px rgba(255,255,255,0.1),
        0 0 0 1px rgba(0,0,0,0.3);
}
.phone-screen {
    border-radius: 28px; overflow: hidden;
    background: #000;
}
.phone-screen img { width: 100%; display: block; }
.phone-mockup-1 {
    left: -80px; top: 20px;
    transform: perspective(1000px) rotateY(15deg) rotateX(5deg);
    animation: phoneFloat1 6s ease-in-out infinite;
}
.phone-mockup-2 {
    left: 40px; top: -40px;
    transform: perspective(1000px) rotateY(-10deg) rotateX(3deg) scale(1.05);
    animation: phoneFloat2 7s ease-in-out infinite;
    z-index: 1;
}
@keyframes phoneFloat1 {
    0%, 100% { transform: perspective(1000px) rotateY(15deg) rotateX(5deg) translateY(0); }
    50%      { transform: perspective(1000px) rotateY(15deg) rotateX(5deg) translateY(-15px); }
}
@keyframes phoneFloat2 {
    0%, 100% { transform: perspective(1000px) rotateY(-10deg) rotateX(3deg) scale(1.05) translateY(0); }
    50%      { transform: perspective(1000px) rotateY(-10deg) rotateX(3deg) scale(1.05) translateY(-20px); }
}

/* Float Elements - 背景装饰，低调处理 */
.float-element {
    position: absolute;
    animation: floatElement 4s ease-in-out infinite;
    opacity: 0.12;
    pointer-events: none;
    filter: blur(0.5px);
}
.float-1 { left: -60px; top: 220px; }
.float-2 { left: 240px; top: 0; animation-delay: 1.5s; }
.float-3 { left: 320px; top: 280px; animation-delay: 0.8s; }
@keyframes floatElement {
    0%, 100% { transform: translateY(0); }
    50%      { transform: translateY(-12px); }
}
.scan-ring {
    width: 44px; height: 44px; border: 2px solid var(--accent);
    border-radius: 50%;
    animation: scanRingRotate 3s linear infinite;
    position: relative;
}
.scan-ring::before {
    content: ''; position: absolute;
    top: -2px; left: 50%; transform: translateX(-50%);
    width: 8px; height: 8px;
    background: var(--accent); border-radius: 50%;
}
@keyframes scanRingRotate { to { transform: rotate(360deg); } }

.data-point {
    width: 10px; height: 10px;
    background: var(--accent); border-radius: 50%;
    box-shadow: 0 0 12px rgba(0, 212, 255, 0.4);
    animation: dataPointPulse 2s ease-in-out infinite;
}
@keyframes dataPointPulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50%      { opacity: .5; transform: scale(1.5); }
}
.float-3 span {
    font-size: 11px; font-weight: 700;
    padding: 4px 12px; background: rgba(0,212,255,0.12);
    border: 1px solid var(--border-accent);
    border-radius: 50px; color: var(--accent);
    white-space: nowrap;
}

/* Scroll Hint */
.scroll-hint {
    position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
    display: flex; flex-direction: column; align-items: center; gap: 8px;
    color: var(--text-muted); font-size: 12px;
}
.mouse {
    width: 22px; height: 34px; border: 2px solid var(--text-muted);
    border-radius: 11px; position: relative;
}
.wheel {
    width: 3px; height: 8px; background: var(--accent); border-radius: 2px;
    position: absolute; top: 6px; left: 50%; transform: translateX(-50%);
    animation: wheelScroll 1.8s ease-in-out infinite;
}
@keyframes wheelScroll {
    0%   { opacity: 1; transform: translateX(-50%) translateY(0); }
    100% { opacity: 0; transform: translateX(-50%) translateY(12px); }
}
.animate-bounce { animation: bounceHint 2s ease-in-out infinite; }
@keyframes bounceHint {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50%      { transform: translateX(-50%) translateY(-6px); }
}

/* ============================================
   SECTION COMMONS
   ============================================ */
.section-header { text-align: center; margin-bottom: 64px; }
.section-tag {
    display: inline-block; padding: 4px 16px;
    background: var(--accent-glow); border: 1px solid var(--border-accent);
    border-radius: 50px; font-size: 13px; font-weight: 600;
    color: var(--accent); margin-bottom: 16px;
}
.section-title {
    font-size: clamp(30px, 4.5vw, 46px); font-weight: 700;
    line-height: 1.2; margin-bottom: 16px; letter-spacing: -0.5px;
}
.section-subtitle {
    font-size: 17px; color: var(--text-secondary); max-width: 560px; margin: 0 auto;
}

/* ============================================
   FEATURES SECTION
   ============================================ */
.features-section { background: var(--bg-secondary); }
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 24px;
}
.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    transition: all var(--transition-smooth);
    position: relative; overflow: hidden;
}
.feature-card::before {
    content: ''; position: absolute; top: 0; left: 0; right: 0;
    height: 2px; background: var(--gradient-main);
    opacity: 0; transition: opacity var(--transition-smooth);
}
.feature-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-accent);
    transform: translateY(-6px);
    box-shadow: var(--shadow-glow), var(--shadow-card);
}
.feature-card:hover::before { opacity: 1; }

.feature-icon-wrap { position: relative; margin-bottom: 20px; }
.feature-icon {
    width: 56px; height: 56px;
    display: flex; align-items: center; justify-content: center;
    background: var(--accent-glow); border-radius: var(--radius-md);
    color: var(--accent);
    position: relative; z-index: 1;
}
.icon-glow {
    position: absolute; inset: -4px;
    background: radial-gradient(circle, rgba(0,212,255,0.2), transparent 70%);
    filter: blur(8px); border-radius: inherit; z-index: 0;
}
.feature-title { font-size: 19px; font-weight: 700; margin-bottom: 10px; }
.feature-desc { font-size: 14px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 16px; }
.feature-tech-tags {
    display: flex; gap: 6px; flex-wrap: wrap;
}
.feature-tech-tags span {
    font-size: 11px; padding: 3px 10px;
    background: rgba(0, 212, 255, 0.06); border: 1px solid rgba(0, 212, 255, 0.12);
    border-radius: 50px; color: var(--accent-light); font-weight: 500;
}

/* ============================================
   SCREENSHOTS SECTION
   ============================================ */
.screenshots-section { background: var(--bg-primary); }
.screenshots-showcase {
    display: flex; align-items: center; justify-content: center;
    gap: 24px; flex-wrap: wrap;
}
.screenshot-item { text-align: center; }
.screenshot-frame {
    border-radius: var(--radius-lg); overflow: hidden;
    background: var(--bg-card); border: 1px solid var(--border-color);
    padding: 8px;
    transition: all var(--transition-smooth);
    box-shadow: var(--shadow-card);
}
.screenshot-frame img {
    border-radius: calc(var(--radius-lg) - 8px);
    width: 220px; height: auto; object-fit: cover;
    aspect-ratio: 9 / 19.5;
    transition: transform var(--transition-smooth);
}
.screenshot-frame:hover {
    border-color: var(--border-accent);
    transform: translateY(-8px) scale(1.02);
    box-shadow: var(--shadow-glow), var(--shadow-card);
}
.screenshot-label {
    margin-top: 12px; font-size: 13px; color: var(--text-muted);
    font-weight: 500;
}

/* ============================================
   HOW IT WORKS / STEPS
   ============================================ */
.how-section { background: var(--bg-secondary); }
.steps-timeline {
    display: flex; justify-content: center; align-items: flex-start;
    gap: 0; max-width: 900px; margin: 0 auto; flex-wrap: wrap;
}
.step-item {
    flex: 1; min-width: 220px; text-align: center; padding: 0 16px;
    position: relative;
}
.step-number {
    font-size: 56px; font-weight: 900;
    background: var(--gradient-main);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text; line-height: 1; margin-bottom: 16px;
    opacity: 0.8;
}
.step-icon { margin-bottom: 16px; color: var(--accent); }
.step-content h3 {
    font-size: 18px; font-weight: 700; margin-bottom: 8px;
}
.step-content p {
    font-size: 14px; color: var(--text-secondary); line-height: 1.7;
}
.step-connector {
    display: flex; align-items: center; padding-top: 50px;
}
.connector-line {
    width: 60px; height: 2px;
    background: linear-gradient(90deg, var(--accent), transparent);
    border-radius: 1px;
}

/* ============================================
   SCENARIOS SECTION
   ============================================ */
.scenarios-section { background: var(--bg-primary); }
.scenarios-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}
.scenario-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    position: relative; overflow: hidden;
    transition: all var(--transition-smooth);
}
.scenario-card:hover {
    border-color: var(--border-accent);
    transform: translateY(-4px);
    box-shadow: var(--shadow-glow);
}
.scenario-bg-pattern {
    position: absolute; inset: 0;
    background: radial-gradient(circle at 80% 20%, rgba(0,212,255,0.06), transparent 60%);
    opacity: 0; transition: opacity var(--transition-smooth);
}
.scenario-card:hover .scenario-bg-pattern { opacity: 1; }
.scenario-content { position: relative; z-index: 1; }
.scenario-emoji { font-size: 36px; display: block; margin-bottom: 14px; }
.scenario-content h3 { font-size: 18px; font-weight: 700; margin-bottom: 8px; }
.scenario-content p { font-size: 14px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 12px; }
.scenario-list li {
    font-size: 13px; color: var(--text-muted);
    padding: 3px 0; padding-left: 16px; position: relative;
}
.scenario-list li::before {
    content: '→'; position: absolute; left: 0;
    color: var(--accent); font-size: 12px;
}

/* ============================================
   STATS SECTION
   ============================================ */
.stats-section {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    text-align: center;
}
.stat-item { padding: 24px 0; }
.stat-number {
    font-size: clamp(36px, 5vw, 52px); font-weight: 900;
    background: var(--gradient-main);
    -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    background-clip: text;
    display: inline;
}
.stat-unit {
    font-size: 20px; font-weight: 700;
    color: var(--accent); display: inline;
}
.stat-label {
    font-size: 14px; color: var(--text-secondary);
    margin-top: 6px;
}

/* ============================================
   DOWNLOAD CTA
   ============================================ */
.download-section { position: relative; overflow: hidden; padding: 120px 0; }
.download-glow-orb {
    position: absolute; width: 500px; height: 500px;
    background: radial-gradient(circle, rgba(0,212,255,0.12), transparent 70%);
    border-radius: 50%; top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    animation: orbPulse 4s ease-in-out infinite alternate;
}
@keyframes orbPulse {
    from { transform: translate(-50%, -50%) scale(1); opacity: .5; }
    to   { transform: translate(-50%, -50%) scale(1.3); opacity: 1; }
}

.download-card {
    text-align: center; position: relative; z-index: 1;
    background: var(--bg-card);
    border: 1px solid var(--border-accent);
    border-radius: var(--radius-xl); padding: 64px 40px;
    overflow: hidden;
}
.download-card-bg {
    position: absolute; inset: 0;
    background: radial-gradient(circle at 50% 0%, rgba(0,212,255,0.08), transparent 60%);
}
.download-content { position: relative; z-index: 1; }
.download-title {
    font-size: clamp(28px, 4vw, 38px); font-weight: 800; margin-bottom: 14px;
}
.download-subtitle {
    font-size: 17px; color: var(--text-secondary); margin-bottom: 32px;
}
.btn-download-lg {
    padding: 18px 44px; font-size: 17px;
    background: var(--gradient-main);
    color: #fff; border-radius: 60px;
    box-shadow: 0 8px 32px rgba(0, 212, 255, 0.3);
    transition: all var(--transition-smooth);
}
.btn-download-lg:hover {
    transform: translateY(-4px) scale(1.03);
    box-shadow: 0 12px 48px rgba(0, 212, 255, 0.45);
}
.download-note {
    margin-top: 16px; font-size: 13px; color: var(--text-muted);
}

/* ============================================
   FOOTER
   ============================================ */
.footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    padding: 56px 0 24px;
}
.footer-main {
    display: flex;
    justify-content: space-between;
    gap: 40px; padding-bottom: 36px;
    border-bottom: 1px solid var(--border-color);
}
.footer-logo { width: 44px; height: 44px; border-radius: 12px; margin-bottom: 12px; }
.footer-brand h4 { font-size: 20px; font-weight: 700; margin-bottom: 6px; }
.footer-brand p { font-size: 14px; color: var(--text-muted); max-width: 260px; }
.footer-links { display: flex; gap: 48px; }
.footer-col h5 {
    font-size: 14px; font-weight: 700; color: var(--text-primary);
    margin-bottom: 14px; text-transform: uppercase; letter-spacing: 1px;
}
.footer-col ul li { margin-bottom: 8px; }
.footer-col ul a, .footer-col ul li:not(:has(a)) {
    font-size: 14px; color: var(--text-muted);
    transition: color var(--transition-fast);
}
.footer-col ul a:hover { color: var(--accent); }
.footer-bottom { padding-top: 20px; text-align: center; }
.footer-bottom p { font-size: 13px; color: var(--text-muted); }

/* ============================================
   BACK TO TOP
   ============================================ */
.back-to-top {
    position: fixed; bottom: 28px; right: 28px; z-index: 999;
    width: 44px; height: 44px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50%; color: var(--text-secondary);
    display: flex; align-items: center; justify-content: center;
    cursor: pointer; opacity: 0; visibility: hidden;
    transition: all var(--transition-smooth);
}
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover {
    background: var(--accent); color: var(--bg-primary);
    border-color: var(--accent);
    transform: translateY(-3px);
}

/* ============================================
   REVEAL ANIMATIONS
   ============================================ */
.reveal {
    opacity: 0; transform: translateY(30px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.revealed {
    opacity: 1; transform: translateY(0);
}
.reveal[data-delay="100"] { transition-delay: 0.1s; }
.reveal[data-delay="150"] { transition-delay: 0.15s; }
.reveal[data-delay="200"] { transition-delay: 0.2s; }
.reveal[data-delay="300"] { transition-delay: 0.3s; }
.reveal[data-delay="400"] { transition-delay: 0.4s; }

.animate-fade-up {
    opacity: 0; transform: translateY(24px);
    animation: fadeUp 0.8s ease forwards;
}
.delay-1 { animation-delay: 0.15s; }
.delay-2 { animation-delay: 0.3s; }
.delay-3 { animation-delay: 0.45s; }
.delay-4 { animation-delay: 0.6s; }
@keyframes fadeUp {
    to { opacity: 1; transform: translateY(0); }
}
.animate-fade-left {
    opacity: 0; transform: translateX(40px);
    animation: fadeLeft 0.9s ease forwards;
}
@keyframes fadeLeft {
    to { opacity: 1; transform: translateX(0); }
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 1024px) {
    .hero-visual { display: none; }
    .hero-content { max-width: 100%; }
    .scenarios-grid { grid-template-columns: 1fr 1fr; }
    .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 32px; }
}

@media (max-width: 768px) {
    .nav-links { display: none; }
    .nav-links.active {
        display: flex; flex-direction: column;
        position: absolute; top: 100%; left: 0; right: 0;
        background: rgba(7, 13, 26, 0.95); backdrop-filter: blur(20px);
        padding: 20px; gap: 16px; border-bottom: 1px solid var(--border-color);
    }
    .nav-download-btn { display: none; }
    .mobile-menu-btn { display: flex; }

    .section { padding: 70px 0; }
    .hero { min-height: auto; padding: 120px 0 80px; }
    .scroll-hint { display: none; }
    .hero-actions { flex-direction: column; align-items: center; }
    .btn { width: 100%; max-width: 280px; }

    .features-grid { grid-template-columns: 1fr; }
    .screenshots-showcase { flex-direction: column; }
    .screenshot-frame img { width: 240px; }

    .steps-timeline { flex-direction: column; align-items: center; gap: 24px; }
    .step-connector { display: none; }

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

    .footer-main { flex-direction: column; }
    .footer-links { flex-wrap: wrap; gap: 28px; }

    .download-card { padding: 40px 24px; }
}

@media (max-width: 480px) {
    html { font-size: 15px; }
    .container { padding: 0 16px; }
    .hero-title { font-size: 36px; }
    .title-accent { font-size: 42px; }
    .stats-grid { grid-template-columns: 1fr 1fr; gap: 16px; }
}