/* ===== Base Reset & Variables ===== */
:root {
    /* Colors */
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --secondary-color: #06b6d4;
    --accent-color: #f59e0b;
    --bg-dark: #0f172a;
    --bg-light: #f8fafc;
    --text-main: #334155;
    --text-muted: #64748b;
    --text-light: #f8fafc;
    --glass-bg: rgba(255, 255, 255, 0.9);
    --glass-border: rgba(255, 255, 255, 0.2);
    
    /* Typography */
    --font-main: 'Inter', sans-serif;
    
    /* Effects */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-glow: 0 0 15px rgba(6, 182, 212, 0.4);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    color: var(--text-main);
    line-height:查 1.6;
    background-color: #ffffff;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--bg-dark);
}

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

ul {
    list-style: none;
}

/* ===== Layout & Utilities ===== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 5rem 0;
}

.section-subtitle {
    color: var(--primary-color);
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 0.875rem;
    margin-bottom: 0.5rem;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
}

.section-desc {
    font-size: 1.125rem;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto 3rem;
    line-height: 1.8;
}

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

.mt-4 { margin-top: 2rem; }
.bg-light { background-color: var(--bg-light); }
.bg-dark { background-color: var(--bg-dark); color: var(--text-light); }

.grid-2-col {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
}

.grid-3-col {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.align-center {
    align-items: center;
}

/* ===== Buttons ===== */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    text-align: center;
    border: 2px solid transparent;
    transition: var(--transition-smooth);
}

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

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

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

.btn-outline:hover {
    background-color: var(--primary-color);
    color: #ffffff;
    transform: translateY(-2px);
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

.btn-block {
    display: block;
    width: 100%;
}

/* ===== Navigation ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: var(--transition-smooth);
    padding: 1.5rem 0;
}

.navbar.scrolled {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: var(--shadow-md);
    padding: 1rem 0;
}

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

.brand {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--bg-dark);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.brand i {
    color: var(--primary-color);
}

.navbar.scrolled .brand {
    color: var(--bg-dark);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    font-weight: 500;
    color: var(--bg-dark);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -4px;
    left: 0;
    background-color: var(--primary-color);
    transition: var(--transition-fast);
}

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

.menu-toggle {
    display: none;
    font-size: 1.5rem;
    color: var(--bg-dark);
    background: none;
    border: none;
    cursor: pointer;
}

.login-btn i {
    margin-right: 0.5rem;
}

/* ===== Hero Section ===== */
.hero {
    position: relative;
    padding: 9rem 0 5rem;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #eef2f3 0%, #8e9eab 100%);
    overflow: hidden;
}

/* Abstract Background Cubes */
.cube {
    position: absolute;
    background: rgba(255, 255, 255, 0.4);
    backdrop-filter: blur(5px);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    animation: float 15s infinite linear;
    z-index: 0;
}

.cube:nth-child(1) { width: 100px; height: 100px; top: 15%; left: 10%; animation-duration: 20s; }
.cube:nth-child(2) { width: 150px; height: 150px; top: 60%; left: 80%; animation-duration: 25s; animation-direction: reverse; }
.cube:nth-child(3) { width: 60px; height: 60px; top: 75%; left: 20%; animation-duration: 15s; }
.cube:nth-child(4) { width: 80px; height: 80px; top: 20%; left: 70%; animation-duration: 18s; }
.cube:nth-child(5) { width: 120px; height: 120px; top: 40%; left: 40%; animation-duration: 22s; animation-direction: reverse; background: rgba(79, 70, 229, 0.1); }

@keyframes float {
    0% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-30px) rotate(180deg); }
    100% { transform: translateY(0) rotate(360deg); }
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 4rem;
    margin-bottom: 1.5rem;
    color: var(--bg-dark);
}

.highlight {
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 2.5rem;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 4rem;
}

.stats-container {
    display: flex;
    justify-content: center;
    gap: 3rem;
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    padding: 2rem;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--glass-border);
}

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

.stat-item i {
    font-size: 2rem;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.stat-item h3 {
    font-size: 1.5rem;
    margin-bottom: 0.25rem;
}

.stat-item p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

/* ===== About Section ===== */
.about-img {
    position: relative;
    display: flex;
    justify-content: center;
}

.img-wrapper {
    width: 100%;
    max-width: 400px;
    aspect-ratio: 1;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
    animation: morph 8s ease-in-out infinite;
    position: relative;
    box-shadow: var(--shadow-glow);
    display: flex;
    align-items: center;
    justify-content: center;
}

@keyframes morph {
    0% { border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%; }
    50% { border-radius: 70% 30% 30% 70% / 70% 70% 30% 30%; }
    100% { border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%; }
}

.abstract-art .circle {
    position: absolute;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
}

.c1 { width: 150px; height: 150px; top: 20%; left: 20%; animation: pulse 2s infinite; }
.c2 { width: 80px; height: 80px; bottom: 30%; right: 20%; animation: pulse 3s infinite; }

@keyframes pulse {
    0% { transform: scale(0.95); opacity: 0.5; }
    50% { transform: scale(1.05); opacity: 1; }
    100% { transform: scale(0.95); opacity: 0.5; }
}

.fiber-lines {
    position: absolute;
    width: 100%;
    height: 100%;
    overflow: hidden;
    border-radius: inherit;
}

.line {
    position: absolute;
    height: 2px;
    width: 150%;
    background: rgba(255,255,255,0.5);
    top: 50%;
    left: -25%;
    transform-origin: center;
}

.line:nth-child(1) { transform: rotate(45deg); }
.line:nth-child(2) { transform: rotate(-30deg); top: 30%; }
.line:nth-child(3) { transform: rotate(15deg); top: 70%; }

.feature-list {
    margin-top: 2rem;
}

.feature-list li {
    margin-bottom: 1rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.feature-list i {
    color: var(--secondary-color);
    font-size: 1.25rem;
}

/* ===== Plans Section ===== */
.plan-card {
    background: #ffffff;
    border-radius: 16px;
    padding: 2.5rem 2rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid #e2e8f0;
    transition: var(--transition-smooth);
    position: relative;
    display: flex;
    flex-direction: column;
}

.plan-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.plan-card.popular {
    transform: scale(1.05);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    z-index: 10;
}

.plan-card.popular:hover {
    transform: scale(1.05) translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.popular-badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    color: #fff;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
    white-space: nowrap;
}

.plan-header h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--bg-dark);
}

.price {
    display: flex;
    justify-content: center;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.currency { font-size: 1.5rem; font-weight: 600; margin-top: 0.5rem; }
.amount { font-size: 3.5rem; font-weight: 800; color: var(--bg-dark); line-height: 1; }
.period { font-size: 1rem; color: var(--text-muted); align-self: flex-end; margin-bottom: 0.5rem; }

.plan-speed {
    background: var(--bg-light);
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 2rem;
}

.speed-value { font-size: 2rem; font-weight: 700; color: var(--primary-color); }
.speed-unit { font-size: 1rem; font-weight: 600; color: var(--text-muted); }

.plan-features {
    text-align: left;
    margin-bottom: 2rem;
    flex-grow: 1;
}

.plan-features li {
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.95rem;
}

.plan-features i {
    color: var(--secondary-color);
    width: 20px;
    text-align: center;
}

.plan-features li.disabled {
    color: var(--text-muted);
    text-decoration: line-through;
}

.plan-features li.disabled i {
    color: #cbd5e1;
}

/* ===== Contact Section ===== */
.info-card {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    margin-bottom: 2rem;
    background: #fff;
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow-sm);
    border: 1px solid #e2e8f0;
    transition: var(--transition-fast);
}

.info-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateX(5px);
}

.icon-box {
    width: 50px;
    height: 50px;
    background: var(--bg-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--primary-color);
    flex-shrink: 0;
}

.info-text h3 {
    font-size: 1.125rem;
    margin-bottom: 0.25rem;
}

.info-text p, .info-text a {
    color: var(--text-muted);
    font-size: 0.95rem;
}

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

.form-wrapper {
    background: #fff;
    padding: 2.5rem;
    border-radius: 16px;
    box-shadow: var(--shadow-lg);
    border: 1px solid #e2e8f0;
}

.form-wrapper h3 {
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition-fast);
    background: var(--bg-light);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
    background: #fff;
}

/* ===== Footer ===== */
.footer {
    background: var(--bg-dark);
    color: var(--text-light);
    padding-top: 5rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-brand .brand {
    color: #fff;
    margin-bottom: 1rem;
}

.footer-brand p {
    color: #94a3b8;
    margin-bottom: 1.5rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
}

.social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-links h3 {
    color: #fff;
    margin-bottom: 1.5rem;
    font-size: 1.25rem;
}

.footer-links ul li {
    margin-bottom: 0.75rem;
}

.footer-links ul a {
    color: #94a3b8;
}

.footer-links ul a:hover {
    color: var(--secondary-color);
    padding-left: 5px;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 1.5rem 0;
    text-align: center;
    color: #94a3b8;
    font-size: 0.875rem;
}

/* ===== Animations ===== */
.reveal {
    opacity: 0;
    transition: all 0.8s ease;
}

.fade-up { transform: translateY(30px); }
.fade-right { transform: translateX(-50px); }
.fade-left { transform: translateX(50px); }

.reveal.active {
    opacity: 1;
    transform: translate(0);
}

.delay-1 { transition-delay: 0.2s; }
.delay-2 { transition-delay: 0.4s; }
.delay-3 { transition-delay: 0.6s; }

/* ===== Responsive Design ===== */
@media (max-width: 992px) {
    .hero h1 { font-size: 3rem; }
    .grid-3-col { grid-template-columns: repeat(2, 1fr); }
    .plan-card.popular { transform: scale(1); }
    .plan-card.popular:hover { transform: translateY(-10px); }
    .footer-content { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 768px) {
    .menu-toggle { display: block; }
    
    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 80%;
        max-width: 300px;
        background: #ffffff;
        flex-direction: column;
        justify-content: center;
        box-shadow: -5px 0 15px rgba(0,0,0,0.1);
        transition: 0.3s ease-in-out;
        z-index: 999;
    }
    
    .nav-links.active {
        right: 0;
    }
    
    .nav-link { margin: 1rem 0; font-size: 1.25rem; }
    
    .hero { padding: 8rem 0 4rem; }
    .hero h1 { font-size: 2.5rem; }
    .hero-buttons { flex-direction: column; width: 100%; max-width: 300px; margin: 0 auto 3rem; }
    
    .stats-container { flex-direction: column; gap: 2rem; }
    
    .grid-2-col, .grid-3-col { grid-template-columns: 1fr; }
    
    .section { padding: 4rem 0; }
    .section-title { font-size: 2rem; }
    
    .footer-content { grid-template-columns: 1fr; gap: 2rem; }
}

@media (max-width: 480px) {
    .hero h1 { font-size: 2rem; }
    .hero p { font-size: 1rem; }
}