:root {
    --primary: #4facfe;
    --secondary: #00f2fe;
    --accent: #00e5ff;
    --bg-dark: #030617;
    --bg-card: rgba(79, 172, 254, 0.06);
    --text: #ffffff;
    --text-muted: rgba(255, 255, 255, 0.7);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { 
    font-family: 'Microsoft YaHei', -apple-system, sans-serif; 
    min-height: 100vh; 
    color: var(--text);
    background: var(--bg-dark);
    overflow-x: hidden;
}

/* 背景效果 */
.bg-effects {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}
.neural-bg {
    position: absolute;
    top: 50%; left: 50%;
    width: 800px; height: 800px;
    transform: translate(-50%, -50%);
    background: 
        radial-gradient(circle at 30% 30%, rgba(79, 172, 254, 0.1) 0%, transparent 50%),
        radial-gradient(circle at 70% 70%, rgba(0, 242, 254, 0.08) 0%, transparent 50%);
    animation: neuralPulse 8s ease-in-out infinite;
}
@keyframes neuralPulse {
    0%, 100% { opacity: 0.5; transform: translate(-50%, -50%) scale(1); }
    50% { opacity: 0.8; transform: translate(-50%, -50%) scale(1.2); }
}

.particles {
    position: absolute;
    width: 100%; height: 100%;
}
.particles span {
    position: absolute;
    width: 3px; height: 3px;
    background: var(--accent);
    border-radius: 50%;
    animation: particleFloat 15s linear infinite;
}
.particles span:nth-child(1) { left: 10%; animation-delay: 0s; animation-duration: 20s; }
.particles span:nth-child(2) { left: 20%; animation-delay: 2s; animation-duration: 18s; }
.particles span:nth-child(3) { left: 30%; animation-delay: 4s; animation-duration: 22s; }
.particles span:nth-child(4) { left: 40%; animation-delay: 1s; animation-duration: 19s; }
.particles span:nth-child(5) { left: 50%; animation-delay: 3s; animation-duration: 21s; }
.particles span:nth-child(6) { left: 60%; animation-delay: 5s; animation-duration: 17s; }
.particles span:nth-child(7) { left: 70%; animation-delay: 2.5s; animation-duration: 23s; }
.particles span:nth-child(8) { left: 80%; animation-delay: 0.5s; animation-duration: 20s; }
.particles span:nth-child(9) { left: 90%; animation-delay: 3.5s; animation-duration: 18s; }
.particles span:nth-child(10) { left: 95%; animation-delay: 1.5s; animation-duration: 24s; }

@keyframes particleFloat {
    0% { transform: translateY(100vh) scale(0); opacity: 0; }
    10% { opacity: 1; }
    90% { opacity: 1; }
    100% { transform: translateY(-100vh) scale(1); opacity: 0; }
}

/* 导航栏 */
nav {
    position: fixed;
    top: 0; left: 0;
    width: 100%;
    z-index: 100;
    padding: 15px 0;
    background: rgba(3, 6, 23, 0.85);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(79, 172, 254, 0.15);
}
.nav-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 30px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.nav-logo { font-size: 28px; animation: logoPulse 2s ease-in-out infinite; }
@keyframes logoPulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}
.nav-links { display: flex; gap: 30px; }
.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 15px;
    transition: all 0.3s;
    position: relative;
}
.nav-links a:hover, .nav-links a.active { color: var(--secondary); }
.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transition: width 0.3s;
}
.nav-links a:hover::after, .nav-links a.active::after { width: 100%; }

.container { max-width: 1200px; margin: 0 auto; padding: 120px 20px 60px; position: relative; z-index: 1; }

/* 英雄区 */
.hero { text-align: center; padding: 40px 20px 80px; }
.hero h1 { 
    font-size: 56px; 
    font-weight: 800; 
    background: linear-gradient(135deg, var(--text) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 20px;
    animation: fadeInUp 0.8s ease-out;
}
.subtitle { 
    font-size: 18px; 
    color: var(--text-muted); 
    margin-bottom: 40px; 
    max-width: 600px; 
    margin-left: auto; 
    margin-right: auto;
    line-height: 1.8;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* AI核心 */
.ai-scene {
    position: relative;
    width: 350px;
    height: 350px;
    margin: 0 auto 50px;
}

.ai-core {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
}
.core-ring {
    position: absolute;
    border-radius: 50%;
    border: 2px solid;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
}
.ring-1 {
    width: 200px; height: 200px;
    border-color: rgba(79, 172, 254, 0.5);
    animation: ringRotate 10s linear infinite;
}
.ring-2 {
    width: 260px; height: 260px;
    border-color: rgba(0, 242, 254, 0.3);
    border-style: dashed;
    animation: ringRotate 15s linear infinite reverse;
}
.ring-3 {
    width: 320px; height: 320px;
    border-color: rgba(79, 172, 254, 0.15);
    animation: ringRotate 20s linear infinite;
}
@keyframes ringRotate {
    from { transform: translate(-50%, -50%) rotate(0deg); }
    to { transform: translate(-50%, -50%) rotate(360deg); }
}

.core-center {
    position: relative;
    width: 120px; height: 120px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 
        0 0 60px rgba(79, 172, 254, 0.6),
        0 0 100px rgba(0, 242, 254, 0.3);
    animation: corePulse 3s ease-in-out infinite;
}
@keyframes corePulse {
    0%, 100% { box-shadow: 0 0 60px rgba(79, 172, 254, 0.6), 0 0 100px rgba(0, 242, 254, 0.3); }
    50% { box-shadow: 0 0 80px rgba(79, 172, 254, 0.8), 0 0 120px rgba(0, 242, 254, 0.5); }
}
.ai-icon {
    font-size: 28px;
    font-weight: 800;
    color: white;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}
.ai-particles {
    position: absolute;
    width: 100%; height: 100%;
    border-radius: 50%;
}
.ai-particles span {
    position: absolute;
    width: 6px; height: 6px;
    background: white;
    border-radius: 50%;
    animation: aiParticle 2s ease-in-out infinite;
}
.ai-particles span:nth-child(1) { top: -5px; left: 50%; animation-delay: 0s; }
.ai-particles span:nth-child(2) { top: 10%; right: -5px; animation-delay: 0.25s; }
.ai-particles span:nth-child(3) { bottom: 10%; right: -5px; animation-delay: 0.5s; }
.ai-particles span:nth-child(4) { bottom: -5px; left: 50%; animation-delay: 0.75s; }
.ai-particles span:nth-child(5) { bottom: 10%; left: -5px; animation-delay: 1s; }
.ai-particles span:nth-child(6) { top: 10%; left: -5px; animation-delay: 1.25s; }
@keyframes aiParticle {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.5); opacity: 0.5; }
}

/* 轨道卫星 */
.orbit {
    position: absolute;
    width: 50px; height: 50px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
    animation: orbitFloat 4s ease-in-out infinite;
}
.orbit-icon { font-size: 24px; }
.orbit-1 { top: 10%; left: 50%; transform: translateX(-50%); animation-delay: 0s; }
.orbit-2 { top: 50%; right: 0; transform: translateY(-50%); animation-delay: 1s; }
.orbit-3 { bottom: 10%; left: 50%; transform: translateX(-50%); animation-delay: 2s; }
.orbit-4 { top: 50%; left: 0; transform: translateY(-50%); animation-delay: 3s; }

@keyframes orbitFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}
.orbit-1, .orbit-3 {
    animation-name: orbitFloatX;
}
@keyframes orbitFloatX {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(-8px); }
}
.orbit-2, .orbit-4 {
    animation-name: orbitFloatY;
}
@keyframes orbitFloatY {
    0%, 100% { transform: translateY(-50%) translateX(0); }
    50% { transform: translateY(-50%) translateX(-5px); }
}

/* 下载按钮 */
.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 40px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    text-decoration: none;
    border-radius: 50px;
    font-size: 16px;
    font-weight: 600;
    color: var(--bg-dark);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    box-shadow: 0 10px 30px rgba(79, 172, 254, 0.3);
    animation: fadeInUp 0.8s ease-out 0.4s both;
}
.download-btn svg { width: 20px; height: 20px; }
.download-btn:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 15px 40px rgba(79, 172, 254, 0.5);
}
.download-btn:active { transform: translateY(0) scale(0.98); }

/* 统计区 */
.stats {
    display: flex;
    justify-content: center;
    gap: 80px;
    margin-top: 60px;
    flex-wrap: wrap;
}
.stat-item {
    text-align: center;
    animation: fadeInUp 0.8s ease-out 0.3s both;
}
.stat-icon { font-size: 36px; margin-bottom: 10px; }
.stat-number { 
    font-size: 48px; 
    font-weight: 800; 
    background: linear-gradient(135deg, var(--secondary) 0%, var(--primary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}
.stat-label { color: var(--text-muted); margin-top: 8px; font-size: 14px; }

/* 功能卡片 */
.features { 
    display: grid; 
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); 
    gap: 25px; 
    margin-top: 80px; 
}
.feature-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 35px 30px;
    border: 1px solid rgba(79, 172, 254, 0.15);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    overflow: hidden;
    animation: fadeInUp 0.8s ease-out both;
}
.feature-card:nth-child(1) { animation-delay: 0.4s; }
.feature-card:nth-child(2) { animation-delay: 0.5s; }
.feature-card:nth-child(3) { animation-delay: 0.6s; }
.feature-card:nth-child(4) { animation-delay: 0.7s; }

.feature-card:hover {
    transform: translateY(-8px);
    border-color: var(--secondary);
    box-shadow: 0 20px 50px rgba(79, 172, 254, 0.15);
}
.feature-card:hover .feature-glow { opacity: 1; }
.feature-glow {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: radial-gradient(circle at 50% 0%, rgba(0, 242, 254, 0.1) 0%, transparent 60%);
    opacity: 0;
    transition: opacity 0.5s;
    pointer-events: none;
}
.feature-icon { font-size: 42px; margin-bottom: 20px; }
.feature-card h3 { font-size: 20px; margin-bottom: 12px; color: var(--text); }
.feature-card p { color: var(--text-muted); line-height: 1.7; font-size: 14px; }

/* ========== 下载页面 ========== */
.download-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 100px 20px 60px;
}
.download-container {
    display: flex;
    align-items: center;
    gap: 80px;
    max-width: 900px;
    width: 100%;
    animation: fadeInUp 0.8s ease-out;
}
.download-visual {
    flex-shrink: 0;
    width: 300px;
    height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.ai-core-small {
    position: relative;
    width: 150px;
    height: 150px;
}
.core-ring-small {
    position: absolute;
    border-radius: 50%;
    border: 2px solid;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
}
.core-ring-small.ring-1 {
    width: 150px; height: 150px;
    border-color: rgba(79, 172, 254, 0.5);
    animation: ringRotateSmall 8s linear infinite;
}
.core-ring-small.ring-2 {
    width: 120px; height: 120px;
    border-color: rgba(0, 242, 254, 0.3);
    border-style: dashed;
    animation: ringRotateSmall 6s linear infinite reverse;
}
@keyframes ringRotateSmall {
    from { transform: translate(-50%, -50%) rotate(0deg); }
    to { transform: translate(-50%, -50%) rotate(360deg); }
}
.core-center-small {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    width: 80px; height: 80px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    font-weight: 800;
    color: white;
    box-shadow: 0 0 40px rgba(79, 172, 254, 0.5);
    animation: corePulse 3s ease-in-out infinite;
}

.download-info {
    flex: 1;
}
.download-badge {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(79, 172, 254, 0.2);
    border: 1px solid var(--primary);
    border-radius: 20px;
    font-size: 12px;
    color: var(--secondary);
    margin-bottom: 20px;
}
.download-info h1 {
    font-size: 48px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--text) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 10px;
}
.version-tag {
    font-size: 18px;
    color: var(--secondary);
    font-weight: 600;
    margin-bottom: 25px;
}
.download-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 25px;
}
.download-meta span {
    font-size: 14px;
    color: var(--text-muted);
}
.download-features {
    margin-bottom: 30px;
}
.df-item {
    padding: 8px 0;
    color: var(--text-muted);
    font-size: 15px;
}
.download-actions {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
    margin-bottom: 25px;
}
.download-btn.primary {
    padding: 16px 40px;
    font-size: 16px;
}
.download-btn.secondary {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--secondary);
    padding: 14px 30px;
}
.download-btn.secondary:hover {
    background: rgba(79, 172, 254, 0.1);
}
.update-time {
    font-size: 13px;
    color: var(--text-muted);
    opacity: 0.7;
}

/* ========== 404页面 ========== */
.error-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 100px 20px 60px;
}
.error-content {
    text-align: center;
    animation: fadeInUp 0.8s ease-out;
}
.error-visual {
    margin-bottom: 40px;
}
.broken-ai {
    width: 150px;
    height: 150px;
    margin: 0 auto;
    position: relative;
    animation: aiErrorPulse 2s ease-in-out infinite;
}
@keyframes aiErrorPulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.05); opacity: 0.8; }
}
.broken-ai::before, .broken-ai::after {
    content: '';
    position: absolute;
    background: var(--bg-dark);
}
.broken-ai::before {
    width: 3px;
    height: 100%;
    left: 50%;
    top: 0;
    transform: translateX(-50%) rotate(15deg);
}
.broken-ai::after {
    width: 80%;
    height: 3px;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%) rotate(-10deg);
}
.broken-ai .ai-part {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    box-shadow: 0 0 50px rgba(79, 172, 254, 0.4);
}
.error-code {
    font-size: 120px;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1;
    margin-bottom: 20px;
}
.error-content h1 {
    font-size: 32px;
    margin-bottom: 15px;
    color: var(--text);
}
.error-content p {
    font-size: 16px;
    color: var(--text-muted);
    margin-bottom: 40px;
}
.error-actions {
    display: flex;
    gap: 15px;
    justify-content: center;
    flex-wrap: wrap;
}

/* 响应式 */
@media (max-width: 768px) {
    .hero h1 { font-size: 40px; }
    .subtitle { font-size: 16px; }
    .stats { gap: 40px; }
    .stat-number { font-size: 36px; }
    .ai-scene { width: 280px; height: 280px; }
    .core-center { width: 90px; height: 90px; }
    .ai-icon { font-size: 22px; }
    .ring-1 { width: 150px; height: 150px; }
    .ring-2 { width: 200px; height: 200px; }
    .ring-3 { width: 250px; height: 250px; }
    .orbit { width: 40px; height: 40px; }
    .orbit-icon { font-size: 18px; }
    .nav-links { gap: 20px; }
    .download-container { flex-direction: column; gap: 40px; text-align: center; }
    .download-visual { width: 200px; height: 200px; }
    .download-info h1 { font-size: 36px; }
    .download-actions { justify-content: center; }
    .error-code { font-size: 80px; }
}