/* ========================================
   快连VPN - 主样式表
   ======================================== */

/* CSS Variables */
:root {
    --primary: #00d4ff;
    --primary-dark: #00a8cc;
    --secondary: #9d00ff;
    --accent: #ff006e;
    --bg-dark: #0a0a0a;
    --bg-card: #111111;
    --bg-card-hover: #1a1a1a;
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.7);
    --text-muted: rgba(255, 255, 255, 0.5);
    --border-color: rgba(255, 255, 255, 0.1);
    --gradient-primary: linear-gradient(135deg, #00d4ff 0%, #9d00ff 100%);
    --gradient-secondary: linear-gradient(135deg, #9d00ff 0%, #ff006e 100%);
    --shadow-glow: 0 0 40px rgba(0, 212, 255, 0.3);
    --transition: all 0.3s ease;
    --radius: 12px;
    --radius-lg: 20px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

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

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    font-size: 14px;
    font-weight: 600;
    border-radius: 50px;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
}

.btn-primary {
    background: var(--gradient-primary);
    color: #fff;
    box-shadow: 0 4px 20px rgba(0, 212, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 30px rgba(0, 212, 255, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-outline:hover {
    border-color: var(--primary);
    background: rgba(0, 212, 255, 0.1);
}

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

.btn-block {
    width: 100%;
}

/* ========================================
   Navigation
   ======================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    background: rgba(10, 10, 10, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 700;
}

.logo-icon {
    font-size: 24px;
}

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

.nav-links a {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

.nav-actions {
    display: flex;
    gap: 12px;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* ========================================
   Hero Section
   ======================================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding: 120px 0 80px;
    position: relative;
    overflow: hidden;
}

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

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    pointer-events: none;
}

.gradient-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.5;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: var(--primary);
    top: -200px;
    right: -200px;
}

.orb-2 {
    width: 400px;
    height: 400px;
    background: var(--secondary);
    bottom: -100px;
    left: -100px;
}

.orb-3 {
    width: 300px;
    height: 300px;
    background: var(--accent);
    top: 50%;
    left: 30%;
    opacity: 0.3;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 50px;
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.hero-title {
    font-size: 64px;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
}

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

.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    gap: 40px;
    margin-bottom: 40px;
}

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

.stat-number {
    font-size: 36px;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.hero-cta {
    display: flex;
    flex-direction: column;
    gap: 16px;
    align-items: flex-start;
}

.cta-note {
    font-size: 14px;
    color: var(--text-muted);
}

/* Device Mockup */
.hero-visual {
    display: flex;
    justify-content: center;
    align-items: center;
}

.device-mockup {
    width: 320px;
    height: 640px;
    background: linear-gradient(145deg, #1a1a2e 0%, #16213e 100%);
    border-radius: 40px;
    padding: 12px;
    box-shadow: 
        0 50px 100px rgba(0, 0, 0, 0.5),
        0 0 0 1px rgba(255, 255, 255, 0.1),
        inset 0 0 0 1px rgba(255, 255, 255, 0.05);
    position: relative;
}

.device-screen {
    width: 100%;
    height: 100%;
    background: var(--bg-dark);
    border-radius: 32px;
    overflow: hidden;
    padding: 24px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 24px;
}

.connection-status {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-size: 18px;
    font-weight: 600;
}

.status-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 10px #22c55e;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.speed-display {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.speed-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 12px;
}

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

.speed-value {
    font-size: 24px;
    font-weight: 700;
}

.speed-value small {
    font-size: 14px;
    color: var(--text-muted);
}

.server-location {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 16px;
    background: var(--gradient-primary);
    border-radius: 12px;
    font-weight: 600;
}

/* ========================================
   Section Headers
   ======================================== */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    padding: 8px 16px;
    background: rgba(0, 212, 255, 0.1);
    border: 1px solid rgba(0, 212, 255, 0.2);
    border-radius: 50px;
    font-size: 14px;
    color: var(--primary);
    margin-bottom: 16px;
}

.section-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 16px;
}

.section-desc {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ========================================
   Features Section
   ======================================== */
.features {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--bg-dark) 0%, var(--bg-card) 100%);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    padding: 32px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    transition: var(--transition);
}

.feature-card:hover {
    background: var(--bg-card-hover);
    border-color: rgba(0, 212, 255, 0.3);
    transform: translateY(-4px);
}

.feature-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gradient-primary);
    border-radius: 16px;
    font-size: 28px;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========================================
   Trust Section
   ======================================== */
.trust {
    padding: 80px 0;
    background: var(--bg-card);
}

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

.trust-content h2 {
    font-size: 32px;
    font-weight: 600;
    margin-bottom: 40px;
}

.trust-badges {
    display: flex;
    justify-content: center;
    gap: 40px;
    flex-wrap: wrap;
}

.trust-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 24px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
}

.trust-icon {
    font-size: 24px;
}

/* ========================================
   Pricing Section
   ======================================== */
.pricing {
    padding: 100px 0;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.pricing-card {
    padding: 40px 32px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    position: relative;
    transition: var(--transition);
}

.pricing-card:hover {
    border-color: rgba(0, 212, 255, 0.3);
}

.pricing-card.popular {
    background: linear-gradient(145deg, var(--bg-card) 0%, rgba(0, 212, 255, 0.05) 100%);
    border-color: var(--primary);
    transform: scale(1.05);
}

.popular-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    padding: 6px 16px;
    background: var(--gradient-primary);
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.pricing-header {
    text-align: center;
    margin-bottom: 32px;
}

.pricing-header h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 16px;
}

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

.pricing-price .currency {
    font-size: 24px;
    font-weight: 600;
}

.pricing-price .amount {
    font-size: 56px;
    font-weight: 800;
}

.pricing-price .period {
    font-size: 16px;
    color: var(--text-secondary);
}

.pricing-save {
    display: inline-block;
    margin-top: 8px;
    padding: 4px 12px;
    background: rgba(34, 197, 94, 0.2);
    color: #22c55e;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
}

.pricing-features {
    margin-bottom: 32px;
}

.pricing-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-color);
    font-size: 14px;
}

.pricing-features li:last-child {
    border-bottom: none;
}

.pricing-features .check {
    color: #22c55e;
    font-weight: 700;
}

.pricing-features .cross {
    color: #ef4444;
    font-weight: 700;
}

/* ========================================
   Download Section
   ======================================== */
.download {
    padding: 100px 0;
    background: linear-gradient(180deg, var(--bg-card) 0%, var(--bg-dark) 100%);
}

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

.download-content h2 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 16px;
}

.download-content p {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 48px;
}

.download-platforms {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.platform-btn {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px 28px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    transition: var(--transition);
}

.platform-btn:hover {
    border-color: var(--primary);
    background: var(--bg-card-hover);
    transform: translateY(-2px);
}

.platform-icon {
    font-size: 32px;
}

.platform-info {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.platform-label {
    font-size: 12px;
    color: var(--text-muted);
}

.platform-name {
    font-size: 16px;
    font-weight: 600;
}

/* ========================================
   Footer
   ======================================== */
.footer {
    padding: 80px 0 40px;
    background: var(--bg-card);
    border-top: 1px solid var(--border-color);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 60px;
}

.footer-brand p {
    margin-top: 16px;
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.footer-links h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 20px;
}

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    font-size: 14px;
    color: var(--text-secondary);
    transition: var(--transition);
}

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

.footer-bottom {
    padding-top: 40px;
    border-top: 1px solid var(--border-color);
    text-align: center;
}

.footer-bottom p {
    font-size: 14px;
    color: var(--text-muted);
}

/* ========================================
   Download Page Styles
   ======================================== */
.page-header {
    padding: 160px 0 60px;
    text-align: center;
    background: linear-gradient(180deg, var(--bg-card) 0%, var(--bg-dark) 100%);
}

.page-header h1 {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 16px;
}

.page-header p {
    font-size: 18px;
    color: var(--text-secondary);
}

.download-section {
    padding: 60px 0 100px;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.download-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: var(--transition);
}

.download-card:hover {
    border-color: rgba(0, 212, 255, 0.3);
}

.download-card-header {
    padding: 32px;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.platform-logo {
    font-size: 48px;
    display: block;
    margin-bottom: 16px;
}

.download-card-header h2 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 8px;
}

.download-card-header p {
    font-size: 14px;
    color: var(--text-secondary);
}

.download-card-body {
    padding: 32px;
}

.system-requirements {
    margin-bottom: 24px;
}

.system-requirements h4 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-secondary);
}

.system-requirements ul {
    font-size: 14px;
    color: var(--text-muted);
}

.system-requirements li {
    padding: 4px 0;
    padding-left: 16px;
    position: relative;
}

.system-requirements li::before {
    content: '•';
    position: absolute;
    left: 0;
    color: var(--primary);
}

.download-options {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.qr-code {
    margin-top: 16px;
    text-align: center;
}

.qr-placeholder {
    width: 120px;
    height: 120px;
    margin: 0 auto;
    background: rgba(255, 255, 255, 0.05);
    border: 1px dashed var(--border-color);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    color: var(--text-muted);
}

.version-info {
    text-align: center;
    font-size: 12px;
    color: var(--text-muted);
    margin-top: 8px;
}

/* Install Guide */
.install-guide {
    padding: 100px 0;
    background: var(--bg-card);
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.step-card {
    text-align: center;
    padding: 40px 32px;
    background: var(--bg-dark);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    position: relative;
    transition: var(--transition);
}

.step-card:hover {
    border-color: rgba(0, 212, 255, 0.3);
}

.step-number {
    position: absolute;
    top: -16px;
    left: 50%;
    transform: translateX(-50%);
    width: 32px;
    height: 32px;
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 700;
}

.step-icon {
    font-size: 48px;
    margin-bottom: 20px;
}

.step-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
}

.step-card p {
    font-size: 14px;
    color: var(--text-secondary);
}

/* FAQ Section */
.faq-section {
    padding: 100px 0;
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    margin-bottom: 16px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    overflow: hidden;
}

.faq-question {
    width: 100%;
    padding: 20px 24px;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 16px;
    font-weight: 500;
    text-align: left;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    transition: var(--transition);
}

.faq-question:hover {
    background: rgba(255, 255, 255, 0.02);
}

.faq-icon {
    font-size: 20px;
    color: var(--primary);
    transition: var(--transition);
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 200px;
}

.faq-answer p {
    padding: 0 24px 20px;
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 1024px) {
    .hero .container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content {
        order: 1;
    }
    
    .hero-visual {
        order: 0;
    }
    
    .hero-title {
        font-size: 48px;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .hero-cta {
        align-items: center;
    }
    
    .device-mockup {
        width: 280px;
        height: 560px;
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
        margin: 0 auto;
    }
    
    .pricing-card.popular {
        transform: none;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .download-grid {
        grid-template-columns: 1fr;
    }
    
    .steps-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .nav-links,
    .nav-actions {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }
    
    .stat-item {
        align-items: center;
    }
    
    .section-title {
        font-size: 32px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .trust-badges {
        flex-direction: column;
        align-items: center;
    }
    
    .download-platforms {
        flex-direction: column;
        align-items: center;
    }
    
    .platform-btn {
        width: 100%;
        max-width: 280px;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }
    
    .page-header h1 {
        font-size: 36px;
    }
}

/* Mobile Menu Active State */
.navbar.active .nav-links {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-card);
    padding: 20px;
    border-bottom: 1px solid var(--border-color);
}

.navbar.active .nav-actions {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: calc(100% + 140px);
    left: 0;
    right: 0;
    background: var(--bg-card);
    padding: 20px;
}

.navbar.active .mobile-menu-btn span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.navbar.active .mobile-menu-btn span:nth-child(2) {
    opacity: 0;
}

.navbar.active .mobile-menu-btn span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}