/**
 * Modern Payment Theme - Main Stylesheet
 * Inspired by Stripe, Alipay, WeChat Pay design systems
 * Version: 1.0.0
 */

/* ========================================
   CSS Variables & Design Tokens
   ======================================== */
:root {
    /* Primary Colors */
    --primary: #635BFF;
    --primary-light: #7A73FF;
    --primary-dark: #4B45CC;
    --primary-50: #F5F4FF;
    --primary-100: #E8E7FF;
    --primary-200: #D4D2FF;
    
    /* Secondary Colors */
    --secondary: #0A2540;
    --secondary-light: #1A3A5C;
    --secondary-dark: #051525;
    
    /* Accent Colors */
    --accent: #00D4FF;
    --accent-light: #33DDFF;
    --accent-dark: #00A3CC;
    
    /* Semantic Colors */
    --success: #30D158;
    --success-light: #E8FAE8;
    --success-dark: #248A3D;
    --warning: #FFD60A;
    --warning-light: #FFFCE8;
    --warning-dark: #B89800;
    --error: #FF453A;
    --error-light: #FFE5E5;
    --error-dark: #D32F2F;
    --info: #0A84FF;
    --info-light: #E5F3FF;
    
    /* Text Colors */
    --text-primary: #1A1F36;
    --text-secondary: #697386;
    --text-muted: #A3ACB9;
    --text-white: #FFFFFF;
    --text-inverse: #FFFFFF;
    
    /* Background Colors */
    --bg-primary: #FFFFFF;
    --bg-secondary: #F6F9FC;
    --bg-tertiary: #E6EBF1;
    --bg-dark: #0A2540;
    
    /* Border Colors */
    --border-color: #E6E8EB;
    --border-light: #F0F2F5;
    --border-dark: #D4D8DD;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #635BFF 0%, #7A73FF 50%, #00D4FF 100%);
    --gradient-secondary: linear-gradient(135deg, #0A2540 0%, #1A3A5C 100%);
    --gradient-accent: linear-gradient(135deg, #FF6B6B 0%, #FFE66D 100%);
    --gradient-success: linear-gradient(135deg, #30D158 0%, #34C759 100%);
    --gradient-mesh: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    
    /* Shadows */
    --shadow-xs: 0 1px 2px rgba(0,0,0,0.04);
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.08), 0 2px 4px -1px rgba(0,0,0,0.04);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.08), 0 4px 6px -2px rgba(0,0,0,0.04);
    --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.08), 0 10px 10px -5px rgba(0,0,0,0.02);
    --shadow-2xl: 0 25px 50px -12px rgba(0,0,0,0.15);
    --shadow-glow: 0 0 40px rgba(99,91,255,0.2);
    --shadow-primary: 0 4px 14px rgba(99,91,255,0.3);
    --shadow-card: 0 2px 8px rgba(0,0,0,0.06), 0 0 1px rgba(0,0,0,0.08);
    
    /* Border Radius */
    --radius-xs: 4px;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-2xl: 32px;
    --radius-full: 9999px;
    
    /* Spacing */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 20px;
    --space-6: 24px;
    --space-8: 32px;
    --space-10: 40px;
    --space-12: 48px;
    --space-16: 64px;
    --space-20: 80px;
    --space-24: 96px;
    
    /* Typography */
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;
    
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.25rem;
    --text-2xl: 1.5rem;
    --text-3xl: 1.875rem;
    --text-4xl: 2.25rem;
    --text-5xl: 3rem;
    --text-6xl: 3.75rem;
    
    --leading-tight: 1.25;
    --leading-snug: 1.375;
    --leading-normal: 1.5;
    --leading-relaxed: 1.625;
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    --transition-bounce: 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    
    /* Z-index */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-fixed: 300;
    --z-modal-backdrop: 400;
    --z-modal: 500;
    --z-popover: 600;
    --z-tooltip: 700;
}

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

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    line-height: var(--leading-normal);
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

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

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

ul, ol {
    list-style: none;
}

/* ========================================
   Layout
   ======================================== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}

@media (max-width: 768px) {
    .container {
        padding: 0 var(--space-4);
    }
}

.main-content {
    min-height: calc(100vh - 80px);
}

/* ========================================
   Header & Navigation
   ======================================== */
.modern-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-fixed);
    background: rgba(255, 255, 255, 0.8);
    -webkit-backdrop-filter: blur(20px);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    transition: all var(--transition-normal);
}

.modern-header.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-sm);
}

.nav-container {
    height: 72px;
    display: flex;
    align-items: center;
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-weight: 600;
    font-size: var(--text-xl);
    color: var(--text-primary);
}

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

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: var(--space-8);
}

.nav-link {
    position: relative;
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text-secondary);
    padding: var(--space-2) 0;
    transition: color var(--transition-fast);
}

.nav-link:hover,
.nav-link.active {
    color: var(--text-primary);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    border-radius: var(--radius-full);
    transition: width var(--transition-normal);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-auth {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 32px;
    height: 32px;
    padding: 4px;
}

.hamburger-line {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile Menu */
.mobile-menu {
    display: none;
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-primary);
    padding: var(--space-6);
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    overflow-y: auto;
}

.mobile-menu.active {
    transform: translateX(0);
}

.mobile-nav-link {
    display: block;
    padding: var(--space-4) 0;
    font-size: var(--text-lg);
    font-weight: 500;
    color: var(--text-primary);
    border-bottom: 1px solid var(--border-light);
}

.mobile-auth {
    margin-top: var(--space-6);
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

@media (max-width: 768px) {
    .nav-menu,
    .nav-auth {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .mobile-menu {
        display: block;
    }
}

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-5);
    font-size: var(--text-sm);
    font-weight: 500;
    line-height: 1;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    white-space: nowrap;
    cursor: pointer;
    border: none;
    outline: none;
}

.btn:focus-visible {
    box-shadow: 0 0 0 3px var(--primary-200);
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 91, 255, 0.4);
    color: var(--text-white);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background: var(--secondary);
    color: var(--text-white);
}

.btn-secondary:hover {
    background: var(--secondary-light);
    color: var(--text-white);
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
}

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

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 1.5px solid var(--border-color);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: var(--primary-50);
}

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

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

.btn-outline-white {
    background: transparent;
    color: var(--text-white);
    border: 1.5px solid rgba(255, 255, 255, 0.3);
}

.btn-outline-white:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.5);
    color: var(--text-white);
}

.btn-lg {
    padding: var(--space-4) var(--space-6);
    font-size: var(--text-base);
    border-radius: var(--radius-lg);
}

.btn-sm {
    padding: var(--space-2) var(--space-3);
    font-size: var(--text-xs);
}

.btn-block {
    width: 100%;
}

.btn-icon {
    width: 40px;
    height: 40px;
    padding: 0;
    border-radius: var(--radius-md);
}

/* ========================================
   Hero Section
   ======================================== */
.hero-section {
    position: relative;
    padding: calc(72px + var(--space-20)) 0 var(--space-20);
    overflow: hidden;
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.hero-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
}

.hero-gradient {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #F5F4FF 0%, #E8F4FF 50%, #F6F9FC 100%);
}

.hero-pattern {
    position: absolute;
    inset: 0;
    background-image: 
        radial-gradient(circle at 25% 25%, rgba(99, 91, 255, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 75% 75%, rgba(0, 212, 255, 0.05) 0%, transparent 50%);
}

.floating-shapes {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.shape {
    position: absolute;
    border-radius: 50%;
    opacity: 0.5;
    animation: float 20s infinite ease-in-out;
}

.shape-1 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(99, 91, 255, 0.1) 0%, transparent 70%);
    top: -100px;
    right: -100px;
    animation-delay: 0s;
}

.shape-2 {
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(0, 212, 255, 0.1) 0%, transparent 70%);
    bottom: 10%;
    left: -50px;
    animation-delay: -5s;
}

.shape-3 {
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, rgba(99, 91, 255, 0.08) 0%, transparent 70%);
    top: 40%;
    right: 20%;
    animation-delay: -10s;
}

.shape-4 {
    width: 150px;
    height: 150px;
    background: radial-gradient(circle, rgba(0, 212, 255, 0.08) 0%, transparent 70%);
    bottom: 30%;
    right: 30%;
    animation-delay: -15s;
}

@keyframes float {
    0%, 100% {
        transform: translate(0, 0) scale(1);
    }
    25% {
        transform: translate(30px, -30px) scale(1.05);
    }
    50% {
        transform: translate(-20px, 20px) scale(0.95);
    }
    75% {
        transform: translate(-30px, -20px) scale(1.02);
    }
}

.hero-section .container {
    position: relative;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
    align-items: center;
}

.hero-content {
    max-width: 560px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    background: var(--bg-primary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-full);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: var(--space-6);
    box-shadow: var(--shadow-sm);
}

.badge-icon {
    font-size: var(--text-base);
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 3.75rem);
    font-weight: 700;
    line-height: var(--leading-tight);
    color: var(--text-primary);
    margin-bottom: var(--space-6);
}

.title-line {
    display: block;
}

.title-highlight {
    display: block;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-description {
    font-size: var(--text-lg);
    color: var(--text-secondary);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-8);
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-4);
    margin-bottom: var(--space-10);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: var(--space-6);
    padding: var(--space-6);
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-card);
    border: 1px solid var(--border-light);
}

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

.stat-value {
    display: block;
    font-size: var(--text-2xl);
    font-weight: 700;
    color: var(--primary);
    margin-bottom: var(--space-1);
}

.stat-label {
    font-size: var(--text-sm);
    color: var(--text-muted);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--border-color);
}

/* Hero Visual - Dashboard Preview */
.hero-visual {
    position: relative;
    height: 450px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.dashboard-preview {
    position: relative;
    width: 100%;
    height: 100%;
}

.dashboard-card {
    background: var(--bg-primary);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    border: 1px solid var(--border-light);
    transition: all var(--transition-normal);
}

.dashboard-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-2xl);
}

.main-card {
    position: absolute;
    top: 10%;
    left: 0;
    width: 320px;
    padding: var(--space-6);
    z-index: 2;
    animation: floatMain 5s ease-in-out infinite;
}

@keyframes floatMain {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.dashboard-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-2);
}

.dashboard-title {
    font-size: var(--text-sm);
    color: var(--text-secondary);
    font-weight: 500;
}

.dashboard-badge {
    font-size: var(--text-xs);
    background: var(--success-light);
    color: var(--success-dark);
    padding: 4px 10px;
    border-radius: var(--radius-full);
    font-weight: 500;
}

.dashboard-amount {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-2);
}

.dashboard-trend {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-4);
}

.trend-up {
    color: var(--success);
    font-weight: 600;
    font-size: var(--text-sm);
}

.trend-text {
    color: var(--text-muted);
    font-size: var(--text-sm);
}

.dashboard-chart {
    height: 60px;
    margin-top: var(--space-4);
}

.dashboard-chart svg {
    width: 100%;
    height: 100%;
}

.side-card {
    position: absolute;
    width: 180px;
    padding: var(--space-4);
    z-index: 1;
}

.card-top {
    top: 5%;
    right: 0;
    animation: floatSide1 5s ease-in-out infinite;
    animation-delay: -1s;
}

.card-bottom {
    bottom: 15%;
    right: 10%;
    animation: floatSide2 5s ease-in-out infinite;
    animation-delay: -2s;
}

@keyframes floatSide1 {
    0%, 100% { transform: translateY(0) rotate(2deg); }
    50% { transform: translateY(-8px) rotate(0deg); }
}

@keyframes floatSide2 {
    0%, 100% { transform: translateY(0) rotate(-1deg); }
    50% { transform: translateY(-6px) rotate(1deg); }
}

.side-card-label {
    font-size: var(--text-xs);
    color: var(--text-muted);
    margin-bottom: var(--space-1);
}

.side-card-value {
    font-size: var(--text-2xl);
    font-weight: 700;
    color: var(--text-primary);
}

.side-card-sub {
    font-size: var(--text-xs);
    color: var(--text-muted);
    margin-top: var(--space-1);
}

.progress-bar {
    height: 6px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    margin-top: var(--space-2);
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--gradient-primary);
    border-radius: var(--radius-full);
}

/* Responsive Hero */
@media (max-width: 1024px) {
    .hero-section .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content {
        max-width: 100%;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .hero-visual {
        display: none;
    }
}

@media (max-width: 640px) {
    .hero-section {
        padding: calc(72px + var(--space-12)) 0 var(--space-12);
        min-height: 0;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: var(--space-4);
    }
    
    .stat-divider {
        width: 60px;
        height: 1px;
    }
    
    .hidden-mobile {
        display: none;
    }
}

/* ========================================
   Features Section
   ======================================== */
.features-section {
    padding: var(--space-24) 0;
    background: var(--bg-primary);
}

.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto var(--space-16);
}

.section-badge {
    display: inline-block;
    padding: var(--space-2) var(--space-4);
    background: var(--primary-50);
    color: var(--primary);
    font-size: var(--text-sm);
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: var(--space-4);
}

.section-title {
    font-size: clamp(1.875rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-4);
}

.section-description {
    font-size: var(--text-lg);
    color: var(--text-secondary);
    line-height: var(--leading-relaxed);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
}

.feature-card {
    padding: var(--space-8);
    background: var(--bg-primary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    transition: all var(--transition-normal);
}

.feature-card:hover {
    border-color: var(--primary-100);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.feature-icon {
    margin-bottom: var(--space-5);
}

.icon-bg {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    border-radius: var(--radius-lg);
}

.gradient-1 { background: linear-gradient(135deg, #635BFF 0%, #7A73FF 100%); }
.gradient-2 { background: linear-gradient(135deg, #00D4FF 0%, #00A3CC 100%); }
.gradient-3 { background: linear-gradient(135deg, #30D158 0%, #248A3D 100%); }
.gradient-4 { background: linear-gradient(135deg, #FF9500 0%, #FF6B00 100%); }
.gradient-5 { background: linear-gradient(135deg, #FF453A 0%, #D32F2F 100%); }
.gradient-6 { background: linear-gradient(135deg, #AF52DE 0%, #8944AB 100%); }

.feature-title {
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-3);
}

.feature-description {
    font-size: var(--text-base);
    color: var(--text-secondary);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-4);
}

.feature-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.feature-list li {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--text-muted);
}

.feature-list li::before {
    content: '';
    width: 6px;
    height: 6px;
    background: var(--primary);
    border-radius: 50%;
}

@media (max-width: 1024px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 640px) {
    .features-section {
        padding: var(--space-16) 0;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .feature-card {
        padding: var(--space-6);
    }
}

/* ========================================
   Payment Methods Section
   ======================================== */
.payment-section {
    padding: var(--space-24) 0;
    background: var(--bg-secondary);
}

.payment-methods {
    display: flex;
    justify-content: center;
    gap: var(--space-8);
    flex-wrap: wrap;
}

.payment-method {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--space-8);
    background: var(--bg-primary);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-xl);
    min-width: 160px;
    transition: all var(--transition-normal);
}

.payment-method:hover {
    border-color: var(--primary-100);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.method-icon {
    width: 64px;
    height: 64px;
    margin-bottom: var(--space-4);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.method-icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.method-icon-fallback {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-2xl);
    font-weight: 700;
    color: white;
    border-radius: var(--radius-lg);
}

.method-icon-fallback.alipay { background: #1677FF; }
.method-icon-fallback.wechat { background: #07C160; }
.method-icon-fallback.qq { background: #12B7F5; }
.method-icon-fallback.unionpay { background: #E21836; }

.method-name {
    font-size: var(--text-base);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-1);
}

.method-desc {
    font-size: var(--text-sm);
    color: var(--text-muted);
}

@media (max-width: 640px) {
    .payment-section {
        padding: var(--space-16) 0;
    }
    
    .payment-methods {
        gap: var(--space-4);
    }
    
    .payment-method {
        min-width: calc(50% - var(--space-2));
        padding: var(--space-6);
    }
}

/* ========================================
   How It Works Section
   ======================================== */
.how-it-works-section {
    padding: var(--space-24) 0;
    background: var(--bg-primary);
}

.steps-container {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: var(--space-4);
}

.step-card {
    flex: 1;
    max-width: 280px;
    text-align: center;
    padding: var(--space-6);
}

.step-number {
    font-size: var(--text-6xl);
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    opacity: 0.2;
    margin-bottom: var(--space-2);
    line-height: 1;
}

.step-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-5);
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-50);
    border-radius: var(--radius-xl);
    color: var(--primary);
}

.step-title {
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-3);
}

.step-description {
    font-size: var(--text-base);
    color: var(--text-secondary);
    line-height: var(--leading-relaxed);
}

.step-connector {
    display: flex;
    align-items: center;
    padding-top: 80px;
    color: var(--border-color);
}

@media (max-width: 1024px) {
    .steps-container {
        flex-direction: column;
        align-items: center;
    }
    
    .step-connector {
        transform: rotate(90deg);
        padding: 0;
        margin: var(--space-4) 0;
    }
    
    .step-card {
        max-width: 400px;
    }
}

@media (max-width: 640px) {
    .how-it-works-section {
        padding: var(--space-16) 0;
    }
}

/* ========================================
   CTA Section
   ======================================== */
.cta-section {
    position: relative;
    padding: var(--space-24) 0;
    overflow: hidden;
}

.cta-bg {
    position: absolute;
    inset: 0;
}

.cta-gradient {
    position: absolute;
    inset: 0;
    background: var(--gradient-secondary);
}

.cta-pattern {
    position: absolute;
    inset: 0;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(99, 91, 255, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 50%, rgba(0, 212, 255, 0.2) 0%, transparent 50%);
}

.cta-content {
    position: relative;
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.cta-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    color: var(--text-white);
    margin-bottom: var(--space-4);
}

.cta-description {
    font-size: var(--text-lg);
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: var(--space-8);
}

.cta-actions {
    display: flex;
    justify-content: center;
    gap: var(--space-4);
    flex-wrap: wrap;
}

@media (max-width: 640px) {
    .cta-section {
        padding: var(--space-16) 0;
    }
    
    .cta-actions {
        flex-direction: column;
    }
    
    .cta-actions .btn {
        width: 100%;
    }
}

/* ========================================
   Footer
   ======================================== */
.modern-footer {
    background: var(--bg-primary);
    border-top: 1px solid var(--border-light);
    padding: var(--space-16) 0 var(--space-8);
}

.footer-main {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--space-16);
    margin-bottom: var(--space-12);
}

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

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-weight: 600;
    font-size: var(--text-lg);
    color: var(--text-primary);
    margin-bottom: var(--space-4);
}

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

.footer-description {
    font-size: var(--text-sm);
    color: var(--text-secondary);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-6);
}

.footer-social {
    display: flex;
    gap: var(--space-3);
}

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.social-link:hover {
    background: var(--primary);
    color: var(--text-white);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
}

.footer-column {
    display: flex;
    flex-direction: column;
}

.column-title {
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-4);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.column-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.column-list a {
    font-size: var(--text-sm);
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.column-list a:hover {
    color: var(--primary);
}

.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-top: var(--space-8);
    border-top: 1px solid var(--border-light);
}

.copyright {
    font-size: var(--text-sm);
    color: var(--text-muted);
}

.footer-badges {
    display: flex;
    gap: var(--space-6);
}

.badge-item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--text-muted);
}

@media (max-width: 768px) {
    .footer-main {
        grid-template-columns: 1fr;
        gap: var(--space-10);
    }
    
    .footer-brand {
        max-width: 100%;
        text-align: center;
    }
    
    .footer-social {
        justify-content: center;
    }
    
    .footer-links {
        grid-template-columns: repeat(3, 1fr);
        text-align: center;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: var(--space-4);
        text-align: center;
    }
}

@media (max-width: 480px) {
    .footer-links {
        grid-template-columns: 1fr;
        gap: var(--space-6);
    }
}

/* ========================================
   Back to Top Button
   ======================================== */
.back-to-top {
    position: fixed;
    bottom: var(--space-6);
    right: var(--space-6);
    width: 48px;
    height: 48px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-full);
    color: var(--text-secondary);
    box-shadow: var(--shadow-lg);
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all var(--transition-normal);
    z-index: var(--z-sticky);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--primary);
    border-color: var(--primary);
    color: var(--text-white);
    transform: translateY(-4px);
}

/* ========================================
   Animations
   ======================================== */
.animate-fade-in {
    animation: fadeIn 0.6s ease forwards;
}

.animate-fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    animation: fadeInUp 0.6s ease forwards;
}

.animate-fade-in-right {
    opacity: 0;
    transform: translateX(30px);
    animation: fadeInRight 0.8s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* Scroll Animations */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   Utility Classes
   ======================================== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.hidden { display: none !important; }
.visible { visibility: visible !important; }
.invisible { visibility: hidden !important; }

.overflow-hidden { overflow: hidden; }
.overflow-auto { overflow: auto; }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }

.w-full { width: 100%; }
.h-full { height: 100%; }

.rounded-full { border-radius: var(--radius-full); }

/* ========================================
   Print Styles
   ======================================== */
@media print {
    .modern-header,
    .modern-footer,
    .back-to-top {
        display: none;
    }
    
    body {
        background: white;
    }
}