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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

.section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 20px;
    color: #1a1a1a;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 2px;
}

.section-subtitle {
    font-size: 1.2rem;
    color: #666;
    max-width: 600px;
    margin: 0 auto;
}

/* Header Styles */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    z-index: 1000;
    transition: all 0.3s ease;
}

.header.scrolled {
    background-color: rgba(255, 255, 255, 0.98);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 25px 30px;
    transition: padding 0.3s ease;
}

.header.scrolled .nav {
    padding: 18px 30px;
}

.nav-brand {
    z-index: 1001;
}

.brand-logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #1a1a1a;
    font-weight: 700;
    font-size: 1.5rem;
    transition: transform 0.3s ease;
}

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

.logo-icon {
    font-size: 2rem;
    margin-right: 10px;
}

.logo-image {
    width: 32px;
    height: 32px;
    margin-right: 10px;
    vertical-align: middle;
}

.brand-name {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 50px;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transition: width 0.3s ease;
}

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

.nav-link:hover {
    color: #667eea;
}

.nav-actions {
    display: flex;
    gap: 20px;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 12px;
    z-index: 1001;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background-color: #333;
    margin: 3px 0;
    transition: all 0.3s ease;
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}

.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* Button Styles */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    cursor: pointer;
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: transparent;
    color: #667eea;
    border-color: #667eea;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: #333;
    border-color: #ddd;
}

.btn-outline:hover {
    background: #333;
    color: white;
    border-color: #333;
}

.btn-large {
    padding: 16px 32px;
    font-size: 1.1rem;
}

.btn-full {
    width: 100%;
}

/* Hero Section */
.hero {
    padding: 120px 0 100px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" viewBox="0 0 60 60" xmlns="http://www.w3.org/2000/svg"><g fill="none" fill-rule="evenodd"><g fill="%23667eea" fill-opacity="0.05"><circle cx="30" cy="30" r="2"/></g></g></svg>') repeat;
    pointer-events: none;
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
    position: relative;
    z-index: 2;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 30px;
    color: #1a1a1a;
}

.title-highlight {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: block;
    margin-top: 10px;
}

.hero-description {
    font-size: 1.3rem;
    color: #666;
    margin-bottom: 40px;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: 20px;
    margin-bottom: 60px;
}

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

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

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: #667eea;
}

.stat-label {
    font-size: 0.9rem;
    color: #666;
    margin-top: 5px;
}

.hero-visual {
    position: relative;
    height: 500px;
}

.hero-image {
    position: relative;
    width: 100%;
    height: 100%;
}

.hero-graphic {
    width: 300px;
    height: 300px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 50%;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    opacity: 0.1;
    animation: pulse 3s infinite;
}

@keyframes pulse {
    0%, 100% { transform: translate(-50%, -50%) scale(1); }
    50% { transform: translate(-50%, -50%) scale(1.1); }
}

.floating-card {
    position: absolute;
    background: white;
    padding: 20px 25px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
    animation: float 3s ease-in-out infinite;
}

.card-1 {
    top: 20%;
    left: 10%;
    animation-delay: 0s;
}

.card-2 {
    top: 60%;
    right: 20%;
    animation-delay: 1s;
}

.card-3 {
    bottom: 20%;
    left: 30%;
    animation-delay: 2s;
}

.card-4 {
    top: 10%;
    right: 10%;
    animation-delay: 0.5s;
}

.card-5 {
    top: 45%;
    left: 5%;
    animation-delay: 1.5s;
}

.card-6 {
    bottom: 35%;
    right: 25%;
    animation-delay: 2.5s;
}

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

.card-icon {
    font-size: 1.5rem;
}

/* What is Section */
.what-is {
    background: #fff;
}

.what-is-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: center;
}

.what-is-text h3 {
    font-size: 2rem;
    margin-bottom: 25px;
    color: #1a1a1a;
}

.what-is-text p {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: 30px;
    line-height: 1.8;
}

.feature-list {
    list-style: none;
}

.feature-list li {
    padding: 10px 0;
    font-size: 1.1rem;
    color: #333;
    border-bottom: 1px solid #f0f0f0;
}

.feature-list li:last-child {
    border-bottom: none;
}

.visual-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    height: 400px;
}

.grid-item {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 20px;
    font-weight: 600;
    font-size: 1.2rem;
    text-align: center;
    transition: transform 0.3s ease;
}

.grid-item:hover {
    transform: scale(1.05);
}

.item-1 { grid-row: 1 / 2; }
.item-2 { grid-row: 1 / 2; }
.item-3 { grid-row: 2 / 3; }
.item-4 { grid-row: 2 / 3; }

/* Why Section */
.why {
    background: #f8f9fa;
}

.why-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
}

.why-item {
    background: white;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.why-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.12);
}

.why-icon {
    font-size: 3rem;
    margin-bottom: 25px;
}

.why-item h3 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: #1a1a1a;
}

.why-item p {
    color: #666;
    line-height: 1.7;
}

/* Features Section */
.features {
    background: white;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.feature-card {
    background: #fff;
    border: 2px solid #f0f0f0;
    border-radius: 20px;
    padding: 40px 30px;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

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

.feature-card:hover {
    border-color: #667eea;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.1);
    transform: translateY(-5px);
}

.feature-card.featured {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: transparent;
}

.feature-card.featured::before {
    background: white;
}

.feature-header {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 20px;
}

.feature-icon {
    font-size: 2.5rem;
}

.feature-card h3 {
    font-size: 1.4rem;
    font-weight: 600;
}

.feature-card p {
    margin-bottom: 25px;
    line-height: 1.7;
    opacity: 0.9;
}

.feature-details {
    list-style: none;
}

.feature-details li {
    padding: 8px 0;
    font-size: 0.95rem;
    opacity: 0.8;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.feature-card:not(.featured) .feature-details li {
    border-bottom-color: rgba(0, 0, 0, 0.1);
}

.feature-details li:last-child {
    border-bottom: none;
}

/* How to Section */
.how-to {
    background: #f8f9fa;
}

.steps-container {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 60px;
    margin-bottom: 60px;
}

.step-item {
    text-align: center;
    max-width: 250px;
}

.step-number {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-size: 2rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 25px;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
}

.step-content h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
    color: #1a1a1a;
}

.step-content p {
    color: #666;
    line-height: 1.6;
}

.step-connector {
    width: 100px;
    height: 2px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    position: relative;
}

.step-connector::after {
    content: '→';
    position: absolute;
    right: -15px;
    top: -10px;
    font-size: 1.2rem;
    color: #667eea;
}

.how-to-guide {
    margin: 80px 0 60px;
    text-align: center;
}

.how-to-guide h3 {
    font-size: 2rem;
    margin-bottom: 40px;
    color: #1a1a1a;
}

.guide-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    max-width: 1000px;
    margin: 0 auto;
}

.guide-item {
    background: white;
    padding: 30px 20px;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    text-align: left;
}

.guide-item h4 {
    font-size: 1.2rem;
    margin-bottom: 15px;
    color: #667eea;
}

.guide-item p {
    color: #666;
    line-height: 1.6;
    font-size: 0.95rem;
}

.how-to-cta {
    text-align: center;
    display: flex;
    gap: 20px;
    justify-content: center;
}

/* Pricing Section */
.pricing {
    background: white;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 40px;
    margin-bottom: 60px;
}

.pricing-card {
    background: white;
    border: 2px solid #f0f0f0;
    border-radius: 25px;
    padding: 40px 30px;
    text-align: center;
    position: relative;
    transition: all 0.3s ease;
}

.pricing-card:hover {
    border-color: #667eea;
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.15);
    transform: translateY(-10px);
}

.pricing-card.popular {
    border-color: #667eea;
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.15);
    transform: scale(1.05);
}

.popular-badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 8px 25px;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 600;
}

.plan-header {
    margin-bottom: 30px;
}

.plan-header h3 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: #1a1a1a;
}

.price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 5px;
    margin-bottom: 30px;
}

.currency {
    font-size: 1.2rem;
    color: #666;
}

.amount {
    font-size: 3rem;
    font-weight: 700;
    color: #667eea;
}

.period {
    font-size: 1.1rem;
    color: #666;
}

.plan-features {
    list-style: none;
    margin-bottom: 40px;
    text-align: left;
}

.plan-features li {
    padding: 12px 0;
    border-bottom: 1px solid #f0f0f0;
    font-size: 0.95rem;
}

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

.pricing-features {
    text-align: center;
    margin-bottom: 40px;
    background: #f8f9fa;
    padding: 40px;
    border-radius: 20px;
}

.pricing-features h3 {
    font-size: 1.5rem;
    margin-bottom: 30px;
    color: #1a1a1a;
}

.features-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 500;
}

.feature-icon {
    font-size: 1.2rem;
}

.pricing-note {
    text-align: center;
    color: #666;
    font-style: italic;
}

/* Promo Codes Section */
.promo-codes {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    position: relative;
    overflow: hidden;
}

.promo-codes::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" viewBox="0 0 60 60" xmlns="http://www.w3.org/2000/svg"><g fill="none" fill-rule="evenodd"><g fill="%23667eea" fill-opacity="0.03"><circle cx="30" cy="30" r="2"/></g></g></svg>') repeat;
    pointer-events: none;
}

.promo-container {
    position: relative;
    z-index: 2;
}

.promo-grid {
    display: grid;
    gap: 40px;
    margin-bottom: 50px;
}

.promo-category {
    background: white;
    border-radius: 20px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    border: 1px solid #e0e0e0;
}

.promo-category h3 {
    font-size: 1.5rem;
    margin-bottom: 25px;
    color: #1a1a1a;
    text-align: center;
    padding-bottom: 15px;
    border-bottom: 2px solid #f0f0f0;
}

.promo-items {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 15px;
}

.promo-item {
    background: #f8f9fa;
    border: 2px solid #e9ecef;
    border-radius: 12px;
    padding: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.promo-item:hover {
    border-color: #667eea;
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.15);
    transform: translateY(-2px);
}

.promo-item:active {
    transform: translateY(0);
    box-shadow: 0 2px 10px rgba(102, 126, 234, 0.2);
}

.promo-item.copied {
    border-color: #28a745;
    background: #d4edda;
}

.promo-item.copied::after {
    content: '✓ 已复制';
    position: absolute;
    top: 5px;
    right: 10px;
    background: #28a745;
    color: white;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 0.8rem;
    font-weight: 600;
}

.promo-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
}

.domain-type {
    font-weight: 600;
    color: #333;
    font-size: 1rem;
}

.price {
    font-weight: 700;
    color: #667eea;
    font-size: 1.1rem;
}

.promo-code {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 8px 12px;
    border-radius: 8px;
    font-family: 'Courier New', monospace;
    font-weight: 700;
    font-size: 1rem;
    text-align: center;
    letter-spacing: 1px;
}

.promo-note {
    margin-top: 8px;
    font-size: 0.85rem;
    color: #666;
    font-style: italic;
    line-height: 1.4;
}

.promo-item.special {
    border-left: 4px solid #ff6b6b;
}

.promo-item.transfer {
    border-left: 4px solid #4ecdc4;
}

.promo-item.general {
    border-left: 4px solid #45b7d1;
}

.promo-notice {
    background: white;
    border-radius: 15px;
    padding: 30px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    border-left: 5px solid #667eea;
}

.promo-notice h4 {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: #1a1a1a;
}

.promo-notice ul {
    list-style: none;
    padding-left: 0;
}

.promo-notice li {
    padding: 8px 0;
    color: #666;
    position: relative;
    padding-left: 25px;
}

.promo-notice li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #667eea;
    font-weight: 700;
}

/* FAQ Section */
.faq {
    background: #f8f9fa;
}

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

.faq-item {
    background: white;
    border-radius: 15px;
    margin-bottom: 20px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
}

.faq-item:hover {
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.faq-question {
    padding: 25px 30px;
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: white;
    transition: background-color 0.3s ease;
}

.faq-question:hover {
    background-color: #f8f9fa;
}

.faq-question h3 {
    font-size: 1.2rem;
    color: #1a1a1a;
    margin: 0;
}

.faq-toggle {
    font-size: 1.5rem;
    font-weight: 300;
    color: #667eea;
    transition: transform 0.3s ease;
}

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

.faq-answer {
    padding: 0 30px;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s ease;
    background: #f8f9fa;
}

.faq-item.active .faq-answer {
    padding: 25px 30px;
    max-height: 200px;
}

.faq-answer p {
    color: #666;
    line-height: 1.7;
    margin: 0;
}

/* Footer */
.footer {
    background: #1a1a1a;
    color: white;
    padding: 80px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr 1.5fr;
    gap: 60px;
    margin-bottom: 50px;
}

.footer-brand p {
    margin-top: 20px;
    color: #ccc;
    line-height: 1.7;
}

.footer-section h4 {
    font-size: 1.2rem;
    margin-bottom: 25px;
    color: white;
}

.footer-section ul {
    list-style: none;
}

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

.footer-section ul li a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #667eea;
}

.contact-info p {
    margin-bottom: 10px;
    color: #ccc;
}

.social-links {
    display: flex;
    gap: 15px;
    margin-top: 20px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: #333;
    border-radius: 50%;
    text-decoration: none;
    transition: all 0.3s ease;
    font-size: 1.2rem;
}

.social-links a:hover {
    background: #667eea;
    transform: translateY(-2px);
}

.footer-divider {
    height: 1px;
    background: #333;
    margin-bottom: 30px;
}

.footer-bottom-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-links {
    display: flex;
    gap: 30px;
}

.footer-links a {
    color: #ccc;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
}

.footer-links a:hover {
    color: #667eea;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.2rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 1000;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3);
}

/* Responsive Design */
@media (max-width: 1024px) {
    .container {
        padding: 0 30px;
    }
    
    .nav {
        padding: 20px 25px;
    }
    
    .header.scrolled .nav {
        padding: 15px 25px;
    }
    
    .nav-menu {
        gap: 35px;
    }
    
    .hero-content {
        gap: 60px;
    }
    
    .hero-title {
        font-size: 3rem;
    }
    
    .what-is-content {
        gap: 60px;
    }
    
    .footer-content {
        grid-template-columns: 2fr 1fr 1fr 1fr;
        gap: 40px;
    }
}

@media (max-width: 768px) {
    .nav {
        padding: 18px 20px;
    }
    
    .header.scrolled .nav {
        padding: 12px 20px;
    }
    
    .nav-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(255, 255, 255, 0.98);
        backdrop-filter: blur(10px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 40px;
        transform: translateX(-100%);
        transition: transform 0.3s ease;
    }
    
    .nav-menu .nav-link {
        font-size: 1.2rem;
        font-weight: 600;
        padding: 15px 0;
    }
    
    .nav-menu.active {
        transform: translateX(0);
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-actions {
        display: none;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        gap: 60px;
        text-align: center;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .what-is-content {
        grid-template-columns: 1fr;
        gap: 50px;
        text-align: center;
    }
    
    .why-grid {
        grid-template-columns: 1fr;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .steps-container {
        flex-direction: column;
        gap: 40px;
    }
    
    .step-connector {
        width: 2px;
        height: 50px;
        transform: rotate(90deg);
    }
    
    .step-connector::after {
        content: '↓';
        right: -8px;
        top: 35px;
    }
    
    .pricing-grid {
        grid-template-columns: 1fr;
    }
    
    .pricing-card.popular {
        transform: none;
    }

    /* 优惠码移动端样式 */
    .promo-items {
        grid-template-columns: 1fr;
        gap: 12px;
    }

    .promo-item {
        padding: 15px;
    }

    .promo-code {
        font-size: 0.9rem;
        padding: 6px 10px;
        letter-spacing: 0.5px;
    }

    .domain-type {
        font-size: 0.9rem;
    }

    .promo-notice {
        padding: 20px;
    }

    .promo-category {
        padding: 20px;
        margin-bottom: 30px;
    }

    .promo-category h3 {
        font-size: 1.3rem;
        margin-bottom: 20px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 40px;
        text-align: center;
    }
    
    .footer-bottom-content {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .how-to-cta {
        flex-direction: column;
        align-items: center;
    }
    
    .logo-image {
        width: 30px;
        height: 30px;
        margin-right: 8px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 20px;
    }
    
    .nav {
        padding: 15px 18px;
    }
    
    .header.scrolled .nav {
        padding: 10px 18px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-description {
        font-size: 1.1rem;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .section-subtitle {
        font-size: 1.1rem;
    }
    
    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }
    
    .btn-large {
        padding: 14px 28px;
        font-size: 1rem;
    }

    /* 优惠码小屏幕样式 */
    .promo-item {
        padding: 12px;
    }

    .promo-info {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
        margin-bottom: 10px;
    }

    .promo-code {
        font-size: 0.85rem;
        width: 100%;
        text-align: center;
        padding: 8px 12px;
    }

    .domain-type {
        font-size: 0.85rem;
        font-weight: 700;
    }

    .price {
        font-size: 1rem;
        color: #667eea;
    }

    .promo-category {
        padding: 15px;
    }

    .promo-category h3 {
        font-size: 1.2rem;
    }

    .promo-notice {
        padding: 15px;
    }

    .promo-notice h4 {
        font-size: 1.1rem;
    }
    
    .logo-image {
        width: 28px;
        height: 28px;
        margin-right: 8px;
    }
}