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

/* CSS Variables - Design System */
:root {
    /* Color System */
    --color-primary: #2ECC71;
    --color-primary-dark: #27AE60;
    --color-primary-light: #A8E6CF;
    --color-accent: #52C41A;
    --color-bg-main: #E8F5E9;
    --color-bg-card: #F1F8F4;
    --color-text-primary: #2C3E50;
    --color-text-secondary: #5A6C7D;
    --color-white: #FFFFFF;
    --color-border: #D5E8D4;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #2ECC71 0%, #27AE60 100%);
    --gradient-light: linear-gradient(180deg, #A8E6CF 0%, #D5E8D4 100%);
    --gradient-card: linear-gradient(45deg, #F1F8F4 0%, #E8F5E9 100%);
    
    /* Neumorphic Shadows */
    --shadow-light-outer: 4px 4px 8px rgba(163, 177, 198, 0.3);
    --shadow-light-inner: -4px -4px 8px rgba(255, 255, 255, 0.8);
    --shadow-medium-outer: 8px 8px 16px rgba(163, 177, 198, 0.4);
    --shadow-medium-inner: -8px -8px 16px rgba(255, 255, 255, 0.9);
    --shadow-deep-outer: 12px 12px 24px rgba(163, 177, 198, 0.5);
    --shadow-deep-inner: -12px -12px 24px rgba(255, 255, 255, 1);
    --shadow-inset-light: inset 4px 4px 8px rgba(163, 177, 198, 0.2);
    --shadow-inset-dark: inset -4px -4px 8px rgba(255, 255, 255, 0.7);
    --shadow-hover-outer: 6px 6px 12px rgba(163, 177, 198, 0.35);
    --shadow-hover-inner: -6px -6px 12px rgba(255, 255, 255, 0.85);
    --shadow-hover-glow: 0 0 20px rgba(46, 204, 113, 0.1);
    
    /* Typography */
    --font-family-primary: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
    --font-family-mono: 'SF Mono', 'Consolas', 'Monaco', monospace;
    
    /* Font Sizes */
    --font-size-hero: 3.5rem;
    --font-size-h1: 2.5rem;
    --font-size-h2: 2rem;
    --font-size-h3: 1.5rem;
    --font-size-h4: 1.25rem;
    --font-size-large: 1.15rem;
    --font-size-base: 1rem;
    --font-size-small: 0.9rem;
    --font-size-xs: 0.8rem;
    
    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 32px;
    --spacing-xl: 48px;
    --spacing-section: 6rem;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-xxl: 24px;
    
    /* Transitions */
    --transition-color: 0.3s ease;
    --transition-transform: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-shadow: 0.35s ease-out;
    --transition-opacity: 0.25s ease-in-out;
    --transition-bounce: 0.45s cubic-bezier(0.34, 1.56, 0.64, 1);
    
    /* Layout */
    --container-max-width: 1400px;
    --container-padding: 20px;
}

body {
    font-family: var(--font-family-primary);
    line-height: 1.7;
    color: var(--color-text-primary);
    background-color: var(--color-bg-main);
    letter-spacing: 0;
}

/* Container */
.container {
    max-width: var(--container-max-width);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* Header */
.header {
    background-color: var(--color-bg-card);
    color: var(--color-text-primary);
    padding: 1.5rem 0;
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
    position: sticky;
    top: 0;
    z-index: 1000;
    min-height: 80px;
    transition: all var(--transition-color);
}

.logo {
    display: inline-block;
    vertical-align: middle;
}

.logo h1 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 0.2rem;
    color: var(--color-primary);
    letter-spacing: 0.02em;
}

.logo p {
    font-size: 0.9rem;
    opacity: 0.9;
    color: var(--color-text-secondary);
}

.nav {
    display: inline-block;
    vertical-align: middle;
    float: right;
}

.nav ul {
    list-style: none;
    display: flex;
}

.nav ul li {
    margin-left: 2rem;
}

.nav ul li a {
    color: var(--color-text-primary);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--font-size-base);
    transition: all var(--transition-color);
    padding: 10px 20px;
    border-radius: var(--radius-md);
    position: relative;
    display: block;
}

.nav ul li a:hover {
    background-color: rgba(46, 204, 113, 0.1);
    color: var(--color-primary);
    box-shadow: var(--shadow-light-outer), var(--shadow-light-inner);
}

.nav ul li a.active {
    background-color: var(--color-primary);
    color: var(--color-white);
    box-shadow: var(--shadow-inset-light), var(--shadow-inset-dark);
}

.nav ul li a.active::after {
    display: none;
}

/* Hero Section */
.hero {
    background: var(--gradient-primary);
    color: var(--color-white);
    padding: 5rem 0;
    text-align: center;
    min-height: 500px;
    max-height: 800px;
    height: 70vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

/* Hero decorative elements */
.hero::before {
    content: '';
    position: absolute;
    width: 300px;
    height: 300px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    top: -100px;
    right: -100px;
    animation: float 6s ease-in-out infinite;
}

.hero::after {
    content: '';
    position: absolute;
    width: 200px;
    height: 200px;
    background: rgba(255, 255, 255, 0.08);
    border-radius: 50%;
    bottom: -50px;
    left: -50px;
    animation: float 8s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) translateX(0);
    }
    50% {
        transform: translateY(-20px) translateX(10px);
    }
}

.hero.hero-small {
    padding: 3rem 0;
    min-height: 300px;
    height: auto;
}

.hero-content {
    max-width: 900px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.hero-content h2 {
    font-size: var(--font-size-hero);
    margin-bottom: 1rem;
    font-weight: 700;
    letter-spacing: 0.02em;
}

.hero-content p {
    font-size: 1.25rem;
    line-height: 1.8;
    margin-bottom: 2rem;
    opacity: 0.95;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.cta-buttons {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.btn {
    display: inline-block;
    padding: 14px 32px;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--font-size-base);
    transition: all var(--transition-transform);
    border: none;
    cursor: pointer;
    position: relative;
    box-shadow: var(--shadow-light-outer), var(--shadow-light-inner);
}

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

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover-outer), var(--shadow-hover-inner), var(--shadow-hover-glow);
}

.btn-primary:active {
    transform: translateY(-1px);
    box-shadow: var(--shadow-inset-light), var(--shadow-inset-dark);
}

.btn-secondary {
    background-color: transparent;
    color: var(--color-white);
    border: 2px solid var(--color-white);
    padding: 12px 30px;
}

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

.btn-secondary:active {
    transform: translateY(-1px);
}

/* Section Title */
.section-title {
    text-align: center;
    font-size: var(--font-size-h1);
    margin-bottom: 3rem;
    color: var(--color-text-primary);
    font-weight: 700;
    letter-spacing: 0.02em;
    position: relative;
    padding-bottom: 1rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 3px;
    background-color: var(--color-primary);
    border-radius: 2px;
}

/* Features Section */
.features {
    padding: var(--spacing-section) 0;
    background-color: var(--color-white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.feature-card {
    background-color: var(--color-bg-card);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
    transition: all var(--transition-transform);
    cursor: pointer;
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-deep-outer), var(--shadow-deep-inner), var(--shadow-hover-glow);
}

.feature-image {
    overflow: hidden;
    height: 240px;
    position: relative;
}

.feature-image::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 50%;
    background: linear-gradient(to top, rgba(0, 0, 0, 0.3), transparent);
    opacity: 0;
    transition: opacity var(--transition-opacity);
}

.feature-card:hover .feature-image::after {
    opacity: 1;
}

.feature-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: var(--radius-md);
    transition: transform var(--transition-transform);
}

.feature-card:hover .feature-image img {
    transform: scale(1.08);
}

.feature-content {
    padding: var(--spacing-md);
}

.feature-content h3 {
    font-size: 1.4rem;
    margin-bottom: 12px;
    color: var(--color-text-primary);
    font-weight: 600;
}

.feature-content p {
    color: var(--color-text-secondary);
    line-height: 1.7;
    font-size: var(--font-size-base);
}

/* Get Started Section */
.get-started {
    padding: 80px 0;
    background: var(--gradient-light);
}

.get-started-content {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 3rem;
    flex-wrap: wrap;
}

.qr-code {
    text-align: center;
    background-color: var(--color-white);
    padding: var(--spacing-md);
    border-radius: var(--radius-xxl);
    box-shadow: var(--shadow-deep-outer), var(--shadow-deep-inner);
    transition: all var(--transition-transform);
    width: 320px;
    height: 320px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.qr-code:hover {
    transform: translateY(-5px) rotate(1deg);
    box-shadow: var(--shadow-deep-outer), var(--shadow-deep-inner), var(--shadow-hover-glow);
}

.qr-code img {
    max-width: 250px;
    height: auto;
    margin-bottom: 1rem;
    border-radius: 4px;
}

.qr-code p {
    font-size: 1.1rem;
    color: var(--color-text-secondary);
    margin: 0;
    font-weight: 500;
}

.search-guide {
    max-width: 400px;
    background-color: rgba(255, 255, 255, 0.9);
    padding: var(--spacing-lg);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
}

.search-guide h3 {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    color: var(--color-text-primary);
    font-weight: 600;
}

.search-guide p {
    margin-bottom: 1rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
    font-size: var(--font-size-base);
    padding-left: 1.5rem;
    position: relative;
}

.search-guide p::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0.6rem;
    width: 8px;
    height: 8px;
    background-color: var(--color-primary);
    border-radius: 50%;
}

/* About Section */
.about {
    padding: var(--spacing-section) 0;
    background: var(--gradient-light);
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
    font-size: var(--font-size-large);
    color: var(--color-text-secondary);
    background-color: var(--color-bg-card);
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
    line-height: 1.9;
}

.about-content p {
    margin-bottom: 24px;
}

.about-content p:last-child {
    margin-bottom: 0;
    font-weight: 600;
    color: var(--color-primary);
}

/* Footer */
.footer {
    background-color: var(--color-text-primary);
    color: var(--color-white);
    padding: var(--spacing-xl) 0;
    text-align: center;
}

.footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.footer-nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    justify-content: center;
}

.footer-nav ul li a {
    color: var(--color-white);
    text-decoration: none;
    opacity: 0.8;
    transition: all var(--transition-color);
    padding: 8px 16px;
    border-radius: var(--radius-md);
    display: inline-block;
}

.footer-nav ul li a:hover {
    opacity: 1;
    background-color: rgba(46, 204, 113, 0.2);
    color: var(--color-primary-light);
}

/* User Guide Section */
.user-guide {
    padding: 3rem 0;
    background-color: var(--color-white);
}

.guide-layout {
    display: grid;
    grid-template-columns: 250px 1fr;
    gap: 2rem;
    align-items: start;
}

/* Guide Sidebar */
.guide-sidebar {
    position: sticky;
    top: 100px;
    height: fit-content;
    background-color: var(--color-bg-card);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
}

.guide-nav h3 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--color-text-primary);
    border-bottom: 2px solid var(--color-primary);
    padding-bottom: 0.5rem;
    font-weight: 600;
}

.guide-nav ul {
    list-style: none;
}

.guide-nav-list > li {
    margin-bottom: 0.5rem;
}

.guide-nav-item {
    margin-bottom: 0.8rem;
}

.guide-nav-item > a {
    font-weight: 600;
    color: var(--color-text-primary);
    font-size: var(--font-size-base);
    padding: 0.6rem 0.8rem;
    display: block;
    text-decoration: none;
    transition: all var(--transition-color);
    border-radius: var(--radius-sm);
}

.guide-nav-item > a:hover {
    color: var(--color-primary);
    background-color: rgba(46, 204, 113, 0.1);
    padding-left: 1.2rem;
    box-shadow: var(--shadow-light-outer), var(--shadow-light-inner);
}

.guide-nav-sublist {
    margin-left: 1.2rem;
    margin-top: 0.4rem;
    margin-bottom: 0.8rem;
}

.guide-nav-sublist li {
    margin-bottom: 0.5rem;
}

.guide-nav-sublist li a {
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: all var(--transition-color);
    display: block;
    padding: 0.4rem 0.8rem;
    font-size: 0.95rem;
    border-radius: var(--radius-sm);
}

.guide-nav-sublist li a:hover {
    color: var(--color-primary);
    background-color: rgba(46, 204, 113, 0.08);
    padding-left: 1.2rem;
    box-shadow: var(--shadow-light-outer), var(--shadow-light-inner);
}

/* Guide Content */
.guide-content {
    background-color: var(--color-white);
    border-radius: var(--radius-md);
    padding: 2rem;
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
}

.guide-title {
    font-size: var(--font-size-h1);
    margin-bottom: 1.5rem;
    color: var(--color-text-primary);
    border-bottom: 2px solid var(--color-primary);
    padding-bottom: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.02em;
}

.guide-subtitle {
    font-size: var(--font-size-h3);
    margin: 2rem 0 1rem;
    color: var(--color-text-primary);
    font-weight: 600;
}

.guide-section {
    font-size: var(--font-size-h4);
    margin: 1.5rem 0 0.8rem;
    color: var(--color-text-secondary);
    font-weight: 500;
}

.guide-content p {
    margin-bottom: 1rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

.guide-image {
    margin: 1.5rem 0;
    text-align: center;
    background-color: transparent;
    padding: 0;
}

.guide-image img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 0 auto;
    max-height: 500px;
    object-fit: contain;
    cursor: pointer;
    transition: all var(--transition-transform);
    border-radius: var(--radius-sm);
}

.guide-image img:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
}

.image-caption {
    padding: 0.5rem 0;
    font-size: 0.9rem;
    color: #666;
    margin: 0.3rem 0 0 0;
    font-weight: 500;
    text-align: center;
}

/* Scroll to Top Button */
.scroll-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background-color: var(--color-primary);
    color: var(--color-white);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-transform);
    z-index: 999;
    box-shadow: var(--shadow-medium-outer), var(--shadow-medium-inner);
    border: none;
    font-size: 24px;
    font-weight: bold;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
    animation: slideInRotate 0.5s ease-out;
}

@keyframes slideInRotate {
    from {
        opacity: 0;
        transform: translateY(20px) rotate(0deg);
    }
    to {
        opacity: 1;
        transform: translateY(0) rotate(360deg);
    }
}

.scroll-top:hover {
    background-color: var(--color-primary-dark);
    transform: translateY(-3px) scale(1.1);
    box-shadow: var(--shadow-deep-outer), var(--shadow-deep-inner), var(--shadow-hover-glow);
}

.scroll-top:active {
    transform: translateY(-1px) scale(1.05) rotate(-360deg);
    transition: transform 0.6s ease-out;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Loading Animation */
img {
    transition: opacity var(--transition-opacity);
}

img.loading {
    opacity: 0;
}

img.loaded {
    opacity: 1;
}

/* Accessibility - Keyboard Navigation */
body.keyboard-navigation *:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

body:not(.keyboard-navigation) *:focus {
    outline: none;
}

/* Skip to main content link */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--color-primary);
    color: var(--color-white);
    padding: 8px 16px;
    text-decoration: none;
    border-radius: 0 0 var(--radius-sm) 0;
    z-index: 10000;
}

.skip-link:focus {
    top: 0;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --color-text-primary: #000000;
        --color-text-secondary: #1a1a1a;
        --color-border: #666666;
    }
    
    .btn,
    .feature-card,
    .qr-code {
        border: 2px solid var(--color-text-primary);
    }
}

/* Image Lightbox Modal */
.lightbox-modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    z-index: 10000;
    justify-content: center;
    align-items: center;
    animation: fadeIn 0.3s ease;
}

.lightbox-modal.active {
    display: flex;
}

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

.lightbox-content {
    position: relative;
    max-width: 90%;
    max-height: 90%;
    animation: zoomIn 0.3s ease;
}

@keyframes zoomIn {
    from {
        transform: scale(0.8);
        opacity: 0;
    }
    to {
        transform: scale(1);
        opacity: 1;
    }
}

.lightbox-content img {
    max-width: 100%;
    max-height: 90vh;
    width: auto;
    height: auto;
    display: block;
    border-radius: var(--radius-md);
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.5);
}

.lightbox-close {
    position: absolute;
    top: -40px;
    right: 0;
    background-color: transparent;
    color: var(--color-white);
    border: none;
    font-size: 36px;
    cursor: pointer;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-color);
    border-radius: 50%;
    line-height: 1;
}

.lightbox-close:hover {
    background-color: rgba(255, 255, 255, 0.1);
    transform: rotate(90deg);
}

.lightbox-caption {
    position: absolute;
    bottom: -40px;
    left: 0;
    right: 0;
    text-align: center;
    color: var(--color-white);
    font-size: 1rem;
    padding: 10px;
    background-color: rgba(0, 0, 0, 0.7);
    border-radius: var(--radius-sm);
}

/* Print styles optimization */
@media print {
    .header,
    .footer,
    .scroll-top,
    .nav {
        display: none !important;
    }
    
    body {
        background-color: white;
        color: black;
    }
    
    .hero {
        background: none;
        color: black;
        page-break-after: always;
    }
}