:root {
    --primary-color: #df3031;
    --primary-hover: #b91c1c;
    --secondary-color: #f3f4f6;
    --text-main: #111827;
    --text-muted: #6b7280;
    --bg-main: #ffffff;
    --bg-alt: #fafafa;
    --nav-height: 70px;
    --transition-speed: 0.3s;
    --font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", STHeiti, "Microsoft Yahei", Tahoma, Simsun, sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

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

/* Typography */
h1, h2, h3, h4 {
    color: var(--text-main);
    font-weight: 700;
}

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

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
    z-index: 1000;
    display: flex;
    justify-content: center;
    transition: background var(--transition-speed), box-shadow var(--transition-speed);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.nav-container {
    width: 100%;
    max-width: 1200px;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo {
    height: 32px;
    width: auto;
}

.nav-brand {
    font-size: 1.125rem;
    font-weight: 600;
}

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

.nav-center a {
    font-size: 0.95rem;
    color: var(--text-muted);
    font-weight: 500;
}

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

.nav-right {
    display: flex;
    align-items: center;
}

/* Buttons */
.btn-primary, .btn-outline {
    display: inline-block;
    padding: 8px 16px;
    border-radius: 8px;
    font-weight: 500;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all var(--transition-speed);
}

.btn-primary {
    background: linear-gradient(135deg, #ef4444, #df3031);
    color: white;
    border: none;
    box-shadow: 0 4px 12px rgba(223, 48, 49, 0.25);
}

.btn-primary:hover {
    box-shadow: 0 6px 16px rgba(223, 48, 49, 0.4);
    transform: translateY(-2px);
    color: white;
}

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

.btn-outline:hover {
    background: var(--secondary-color);
}

.btn-primary.large, .btn-outline.large {
    padding: 14px 28px;
    font-size: 1.1rem;
    border-radius: 12px;
}

/* Hero Section */
.hero {
    padding: calc(var(--nav-height) + 80px) 24px 60px;
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: center;
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
    background: none;
}

.hero-content {
    flex: 1;
    max-width: 600px;
    text-align: left;
    margin-bottom: 0;
}

.badge {
    display: inline-block;
    padding: 6px 14px;
    background: #fee2e2;
    color: #b91c1c;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 24px;
}

.hero-title {
    font-size: 3.5rem;
    line-height: 1.2;
    margin-bottom: 24px;
    background: linear-gradient(90deg, #111827, #374151, #df3031);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    margin-bottom: 40px;
    max-width: 600px;
    margin-left: 0;
    margin-right: 0;
}

.hero-actions {
    display: flex;
    justify-content: flex-start;
    gap: 16px;
}

.hero-image-wrapper {
    flex: 1;
    width: 100%;
    max-width: 600px;
    border-radius: 20px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.15);
    overflow: hidden;
    border: 1px solid rgba(0,0,0,0.05);
}

.hero-image {
    width: 100%;
    height: auto;
    display: block;
}

/* Features Section */
.features {
    padding: 100px 24px;
    background-color: var(--bg-alt);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.section-header {
    text-align: center;
    max-width: 600px;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.section-header p {
    font-size: 1.1rem;
    color: var(--text-muted);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
    max-width: 1200px;
    width: 100%;
}

.feature-card {
    background: white;
    padding: 40px 30px;
    border-radius: 16px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid rgba(0,0,0,0.02);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
}

.feature-icon {
    width: 60px;
    height: 60px;
    background: #fee2e2;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
}

.feature-icon img {
    width: 32px;
    height: 32px;
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 12px;
}

.feature-card p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* CTA Section */
.cta-section {
    padding: 100px 24px;
    background: linear-gradient(135deg, #7f1d1d, #ef4444);
    color: white;
    text-align: center;
}

.cta-content {
    max-width: 600px;
    margin: 0 auto;
}

.cta-content h2 {
    color: white;
    font-size: 2.5rem;
    margin-bottom: 16px;
}

.cta-content p {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 32px;
}

.cta-btn {
    background: white;
    color: var(--primary-color);
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
}

.cta-btn:hover {
    background: #f8fafc;
    color: var(--primary-hover);
    box-shadow: 0 12px 30px rgba(0,0,0,0.3);
}

/* Footer */
.footer {
    padding: 40px 24px;
    border-top: 1px solid #eaeaea;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    background: white;
}

/* Animations */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.delay-1 { transition-delay: 0.1s; }
.delay-2 { transition-delay: 0.2s; }

/* Responsive */
@media (max-width: 768px) {
    .nav-center { display: none; }
    .hero { flex-direction: column; text-align: center; }
    .hero-content { text-align: center; margin-bottom: 40px; }
    .hero-subtitle { margin-left: auto; margin-right: auto; }
    .hero-actions { flex-direction: column; justify-content: center; }
    .hero-title { font-size: 2.5rem; }
    .btn-primary.large, .btn-outline.large { width: 100%; text-align: center; }
}