:root {
    --primary: #667eea;
    --primary-dark: #5568d3;
    --secondary: #764ba2;
    --accent: #f093fb;
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-light: #718096;
    --bg-light: #f7fafc;
    --bg-white: #ffffff;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    --ease-out-expo: cubic-bezier(0.19, 1, 0.22, 1);
    --ease-in-out-back: cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

@keyframes float-slow {
    0%, 100% { transform: translateY(0px) rotate(0deg); }
    50% { transform: translateY(-30px) rotate(3deg); }
}

@keyframes glow {
    0%, 100% { box-shadow: 0 0 20px rgba(102, 126, 234, 0.3); }
    50% { box-shadow: 0 0 40px rgba(102, 126, 234, 0.6); }
}

@keyframes fade-in-up {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes scale-in {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    scroll-behavior: smooth;
}

html {
    scroll-behavior: smooth;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    z-index: 1000;
    border-bottom: 1px solid transparent;
    transition: all 0.3s var(--ease-out-expo);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    transition: transform 0.3s var(--ease-out-expo);
}

.logo:hover {
    transform: scale(1.05);
}

.logo img {
    transition: transform 0.5s var(--ease-out-expo);
}

.logo:hover img {
    transform: rotate(360deg);
}

.logo-icon {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

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

.nav-links .nav-cta {
    padding: 10px 18px;
    border-radius: 12px;
    color: white;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    box-shadow: var(--shadow);
    font-weight: 700;
}

.nav-links .nav-cta:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    color: white;
}
.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s var(--ease-out-expo);
    position: relative;
    padding: 8px 0;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transition: width 0.3s var(--ease-out-expo);
}

.nav-links a:hover {
    color: var(--primary);
    transform: translateY(-2px);
}

.nav-links a:hover::after {
    width: 100%;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: 12px;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.4s var(--ease-out-expo);
    border: none;
    cursor: pointer;
    font-size: 16px;
    position: relative;
    overflow: hidden;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, transparent 100%);
    opacity: 0;
    transition: opacity 0.3s;
}

.btn:hover::before {
    opacity: 1;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    background-size: 200% 200%;
    color: white;
    box-shadow: var(--shadow);
    animation: gradient-shift 3s ease infinite;
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: var(--shadow-xl);
}

.btn-primary:active {
    transform: translateY(-1px) scale(0.98);
}

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

.btn-secondary:hover {
    background: var(--primary);
    color: white;
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 2px solid var(--border);
}

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

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

/* Hero Section */
.hero {
    position: relative;
    padding: 140px 0 100px;
    overflow: hidden;
    background: linear-gradient(135deg, #667eea08 0%, #764ba208 100%);
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(102, 126, 234, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(118, 75, 162, 0.15) 0%, transparent 50%),
        radial-gradient(circle at 60% 20%, rgba(240, 147, 251, 0.1) 0%, transparent 40%);
    animation: float-slow 20s ease-in-out infinite;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent 30%, rgba(102, 126, 234, 0.05) 50%, transparent 70%);
    animation: gradient-shift 15s linear infinite;
}

.hero .container {
    position: relative;
    display: flex;
    align-items: center;
    gap: 80px;
}

.hero-content {
    flex: 1;
}

.hero-title {
    font-size: 56px;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    animation: fade-in-up 0.8s var(--ease-out-expo) 0.2s both;
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 50%, var(--secondary) 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradient-shift 4s ease infinite;
    display: inline-block;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.8;
    animation: fade-in-up 0.8s var(--ease-out-expo) 0.4s both;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 60px;
    animation: fade-in-up 0.8s var(--ease-out-expo) 0.6s both;
}

.hero-stats {
    display: flex;
    gap: 48px;
    animation: fade-in-up 0.8s var(--ease-out-expo) 0.8s both;
}

.stat {
    text-align: center;
    transition: transform 0.3s var(--ease-out-expo);
    cursor: default;
}

.stat:hover {
    transform: translateY(-5px);
}

.stat-number {
    font-size: 32px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: gradient-shift 3s ease infinite;
}

.stat-label {
    font-size: 14px;
    color: var(--text-light);
    margin-top: 4px;
}

/* Phone Mockup */
.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.phone-mockup {
    width: 290px;
    height: 560px;
    background: linear-gradient(145deg, #2f2f2f, #1d1d1f);
    border-radius: 36px;
    padding: 10px;
    box-shadow: 
        0 20px 60px rgba(0, 0, 0, 0.25),
        0 0 0 1px rgba(255, 255, 255, 0.05),
        inset 0 1px 0 rgba(255, 255, 255, 0.08);
    position: relative;
    animation: float 6s ease-in-out infinite, glow 3s ease-in-out infinite;
    transform-style: preserve-3d;
}

@keyframes float {
    0%, 100% { 
        transform: translateY(0px) rotateY(-5deg);
    }
    50% { 
        transform: translateY(-30px) rotateY(5deg);
    }
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, #f7f8fb 0%, #e9edf6 100%);
    border-radius: 30px;
    overflow: hidden;
    padding: 52px 16px 16px;
    position: relative;
}

.phone-screen::before {
    content: '';
    position: absolute;
    top: 16px;
    left: 50%;
    transform: translateX(-50%);
    width: 110px;
    height: 26px;
    background: #121212;
    border-radius: 0 0 18px 18px;
    box-shadow: inset 0 -2px 6px rgba(0,0,0,0.3);
}

.screen-content {
    width: 100%;
    height: 100%;
    background: white;
    border-radius: 18px;
    padding: 18px;
    box-shadow: inset 0 1px 0 rgba(255,255,255,0.7);
    position: relative;
}

.status-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 14px;
    opacity: 0.6;
}

.signal, .battery {
    width: 40px;
    height: 8px;
    background: linear-gradient(90deg, #cfd7e6, #9aa7c2);
    border-radius: 4px;
}

.camera-hole {
    width: 8px;
    height: 8px;
    background: #111;
    border-radius: 50%;
    box-shadow: 0 0 0 3px rgba(0,0,0,0.1);
}

.app-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.app-icon.small {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.app-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
}

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

.chat-area {
    margin-top: 16px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.chat-bubble {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.bubble {
    padding: 12px 14px;
    border-radius: 16px;
    max-width: 78%;
    animation: slideIn 0.3s ease-out;
    font-size: 15px;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.bubble.user {
    align-self: flex-end;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    box-shadow: 0 12px 24px rgba(102, 126, 234, 0.25);
}

.bubble.ai {
    align-self: flex-start;
    background: #f2f4f8;
    display: flex;
    gap: 4px;
}

.typing-dot {
    width: 8px;
    height: 8px;
    background: var(--text-light);
    border-radius: 50%;
    animation: typing 1.4s infinite;
}

.typing-dot:nth-child(2) { animation-delay: 0.2s; }
.typing-dot:nth-child(3) { animation-delay: 0.4s; }

@keyframes typing {
    0%, 60%, 100% { transform: translateY(0); }
    30% { transform: translateY(-10px); }
}

/* Features Section */
.features {
    padding: 100px 0;
    background: white;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 20px;
    color: var(--text-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 32px;
}

.feature-card {
    padding: 32px;
    border-radius: 20px;
    background: white;
    border: 2px solid var(--border);
    transition: all 0.4s var(--ease-out-expo);
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary)05, var(--secondary)05);
    opacity: 0;
    transition: opacity 0.4s;
}

.feature-card:hover::before {
    opacity: 1;
}

.feature-card:hover {
    transform: translateY(-12px) scale(1.02);
    box-shadow: var(--shadow-2xl);
    border-color: var(--primary);
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    transition: all 0.4s var(--ease-out-expo);
    position: relative;
}

.feature-card:hover .feature-icon {
    transform: translateY(-5px) rotate(5deg) scale(1.1);
    box-shadow: var(--shadow-lg);
}

.feature-icon svg {
    color: white;
    transition: transform 0.4s var(--ease-out-expo);
}

.feature-card:hover .feature-icon svg {
    transform: scale(1.2);
}

.feature-card h3 {
    font-size: 24px;
    margin-bottom: 12px;
    font-weight: 600;
}

.feature-card p {
    color: var(--text-secondary);
    line-height: 1.7;
}

/* Pricing Section */
.pricing {
    padding: 100px 0;
    background: var(--bg-light);
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 32px;
}

.pricing-grid.two-column {
    grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
}

.subscription-note {
    margin-top: 32px;
    padding: 20px 24px;
    background: var(--bg-light);
    border: 1px solid var(--border);
    border-radius: 16px;
    color: var(--text-secondary);
    line-height: 1.7;
}

.subscription-note h4 {
    margin-bottom: 12px;
    font-size: 18px;
    color: var(--text-primary);
}

.subscription-note ul {
    margin-left: 18px;
    margin-bottom: 0;
}

.subscription-note a {
    color: var(--primary);
    text-decoration: none;
    font-weight: 600;
}

.subscription-note a:hover {
    text-decoration: underline;
}

.pricing-card {
    background: white;
    border-radius: 20px;
    padding: 40px;
    border: 2px solid var(--border);
    transition: all 0.4s var(--ease-out-expo);
    position: relative;
    overflow: hidden;
}

.pricing-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transform: scaleX(0);
    transition: transform 0.4s var(--ease-out-expo);
}

.pricing-card:hover::before {
    transform: scaleX(1);
}

.pricing-card:hover {
    transform: translateY(-12px) scale(1.03);
    box-shadow: var(--shadow-2xl);
    border-color: var(--primary);
}

.pricing-card.featured {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, #ffffff 0%, #f8f9ff 100%);
}

.pricing-card.featured::before {
    transform: scaleX(1);
}

.badge {
    position: absolute;
    top: -12px;
    right: 32px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    background-size: 200% auto;
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 600;
    animation: gradient-shift 3s ease infinite, float 2s ease-in-out infinite;
    box-shadow: var(--shadow);
}

.pricing-header {
    text-align: center;
    padding-bottom: 32px;
    border-bottom: 2px solid var(--border);
    margin-bottom: 32px;
}

.pricing-header h3 {
    font-size: 24px;
    margin-bottom: 20px;
}

.price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 4px;
}

.currency {
    font-size: 24px;
    color: var(--text-secondary);
}

.amount {
    font-size: 56px;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.period {
    font-size: 18px;
    color: var(--text-light);
}

.pricing-features {
    list-style: none;
    margin-bottom: 32px;
}

.pricing-features li {
    padding: 12px 0;
    color: var(--text-secondary);
}

.pricing-card .btn {
    width: 100%;
}

/* Download Section */
.download {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 50%, var(--secondary) 100%);
    background-size: 200% auto;
    color: white;
    text-align: center;
    position: relative;
    overflow: hidden;
    animation: gradient-shift 10s ease infinite;
}

.download::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    animation: float-slow 20s ease-in-out infinite;
}

.download-content {
    position: relative;
    z-index: 1;
}

.download-content h2 {
    font-size: 48px;
    margin-bottom: 16px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.download-content p {
    font-size: 20px;
    margin-bottom: 40px;
    opacity: 0.95;
    text-shadow: 0 1px 5px rgba(0,0,0,0.1);
}

.download .btn-primary {
    background: white;
    color: var(--primary);
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.download .btn-primary:hover {
    transform: translateY(-5px) scale(1.05);
    box-shadow: 0 15px 40px rgba(0,0,0,0.3);
}

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 60px 0 30px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    margin-bottom: 40px;
}

.footer-brand {
    max-width: 300px;
}

.footer-brand .logo {
    margin-bottom: 16px;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.7);
}

.footer-links {
    display: flex;
    gap: 80px;
}

.footer-column h4 {
    margin-bottom: 16px;
    font-size: 16px;
}

.footer-column a {
    display: block;
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    margin-bottom: 12px;
    transition: color 0.3s;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.5);
}

/* Responsive */
@media (max-width: 1024px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .hero-title {
        font-size: 40px;
    }
    
    .section-title {
        font-size: 36px;
    }
    
    .features-grid,
    .pricing-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 40px;
    }
    
    .footer-links {
        gap: 40px;
    }
}