*{margin:0;padding:0;box-sizing:border-box}:root{--color-white: #FFFFFF;--color-black: #1d1d1f;--color-gray-light: #f5f5f7;--color-brand-blue: #0071e3;--color-brand-blue-hover: #0077ed;--font-sans-zh: "PingFang SC", -apple-system, BlinkMacSystemFont, sans-serif;--font-sans-en: "SF Pro Display", "Helvetica Neue", Arial, sans-serif;--spacing-xs: 8px;--spacing-sm: 16px;--spacing-md: 24px;--spacing-lg: 32px;--spacing-xl: 48px;--spacing-2xl: 64px;--ease-apple: cubic-bezier(.4, 0, .2, 1);--ease-apple-in: cubic-bezier(.4, 0, 1, 1);--ease-apple-out: cubic-bezier(0, 0, .2, 1)}html{scroll-behavior:smooth;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}body{font-family:var(--font-sans-zh),var(--font-sans-en);color:var(--color-black);background-color:var(--color-white);overflow-x:hidden;line-height:1.6}.video-container{position:fixed;top:0;left:0;width:100vw;height:100vh;z-index:-1;overflow:hidden}.background-video{position:absolute;top:50%;left:50%;min-width:100%;min-height:100%;width:auto;height:auto;transform:translate(-50%,-50%);object-fit:cover;opacity:0;transition:opacity 1.2s var(--ease-apple);z-index:1}.background-video.active{opacity:1;z-index:2}.white-transition{position:absolute;top:0;left:0;width:100%;height:100%;background:#000;opacity:0;transition:opacity 1.2s var(--ease-apple);z-index:2;pointer-events:none}.white-transition.show{opacity:1;z-index:3}.video-overlay{position:absolute;top:0;left:0;width:100%;height:100%;background:#0000001a;pointer-events:none;z-index:4}.intro-text-container{position:fixed;top:0;left:0;width:100vw;height:100vh;display:flex;align-items:center;justify-content:center;z-index:10;pointer-events:none}.intro-text{position:absolute;opacity:0;transform:translateY(20px);transition:opacity 1.5s var(--ease-apple),transform 1.5s var(--ease-apple)}.intro-text.show{opacity:1;transform:translateY(0)}.intro-text.hide{opacity:0;transform:translateY(-20px)}.intro-text h2{font-size:clamp(24px,4vw,48px);font-weight:600;color:var(--color-white);text-align:center;letter-spacing:.02em;text-shadow:0 4px 24px rgba(0,0,0,.3);padding:0 var(--spacing-md)}.header{position:fixed;top:0;left:0;width:100%;height:60px;background-color:#ffffffb3;backdrop-filter:blur(20px) saturate(180%);-webkit-backdrop-filter:blur(20px) saturate(180%);border-bottom:1px solid rgba(0,0,0,.05);z-index:100;opacity:0;transform:translateY(-10px);transition:opacity 2s var(--ease-apple),transform 2s var(--ease-apple)}.header.show{opacity:1;transform:translateY(0)}.nav-container{max-width:1200px;margin:0 auto;height:100%;display:flex;align-items:center;justify-content:space-between;padding:0 var(--spacing-md)}.logo{display:flex;align-items:center;cursor:pointer;transition:transform .3s var(--ease-apple)}.logo:hover{transform:scale(1.05)}.nav-links{display:flex;list-style:none;gap:var(--spacing-lg);align-items:center}.nav-links li{position:relative}.nav-links a{text-decoration:none;color:var(--color-black);font-size:14px;font-weight:500;letter-spacing:.01em;transition:color .3s var(--ease-apple);position:relative;padding:8px 0}.nav-links a:after{content:"";position:absolute;bottom:0;left:0;width:0;height:2px;background-color:var(--color-brand-blue);transition:width .3s var(--ease-apple)}.nav-links a:hover{color:var(--color-brand-blue)}.nav-links a:hover:after{width:100%}.hero-section{position:relative;width:100vw;height:100vh;display:flex;align-items:center;justify-content:center;opacity:0;transform:translateY(20px);transition:opacity 2s var(--ease-apple),transform 2s var(--ease-apple)}.hero-section.show{opacity:1;transform:translateY(0)}.hero-content{text-align:center;max-width:800px;padding:0 var(--spacing-md)}.hero-title{font-size:clamp(36px,6vw,72px);font-weight:700;color:var(--color-white);letter-spacing:-.02em;line-height:1.1;margin-bottom:var(--spacing-md);text-shadow:0 4px 32px rgba(0,0,0,.4)}.hero-subtitle{font-size:clamp(16px,2.5vw,24px);font-weight:400;color:#ffffffe6;line-height:1.5;margin-bottom:var(--spacing-xl);text-shadow:0 2px 16px rgba(0,0,0,.3)}.cta-container{display:flex;gap:var(--spacing-sm);justify-content:center;flex-wrap:wrap}.cta-button{padding:14px 32px;font-size:16px;font-weight:600;border:none;border-radius:24px;cursor:pointer;transition:all .3s var(--ease-apple);letter-spacing:.01em;font-family:inherit}.cta-button.primary{background-color:var(--color-black);color:var(--color-white);box-shadow:0 4px 16px #0006}.cta-button.primary:hover{background-color:#2c2c2e;box-shadow:0 6px 24px #00000080;transform:translateY(-2px)}.cta-button.primary:active{transform:translateY(0);background-color:var(--color-black)}.cta-button.secondary{background-color:#fff3;color:var(--color-white);backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border:1px solid rgba(255,255,255,.3)}.cta-button.secondary:hover{background-color:#ffffff4d;border-color:#ffffff80;transform:translateY(-2px)}.mobile-play-prompt{position:fixed;top:0;left:0;width:100vw;height:100vh;background:linear-gradient(135deg,#667eea,#764ba2);display:none;align-items:center;justify-content:center;z-index:1000}.mobile-play-button{display:flex;flex-direction:column;align-items:center;gap:var(--spacing-md);background:none;border:none;cursor:pointer;padding:var(--spacing-md);transition:transform .3s var(--ease-apple)}.mobile-play-button:hover{transform:scale(1.05)}.mobile-play-button span{color:var(--color-white);font-size:16px;font-weight:500}@media (max-width: 1024px){.nav-links{gap:var(--spacing-md)}.nav-links a{font-size:13px}}@media (max-width: 768px){:root{--spacing-xl: 32px;--spacing-2xl: 48px}.header{height:48px}.nav-container{padding:0 var(--spacing-sm)}.logo svg{width:28px;height:28px}.nav-links{gap:var(--spacing-sm)}.nav-links a{font-size:12px}.hero-content{padding:0 var(--spacing-sm)}.hero-title{margin-bottom:var(--spacing-sm)}.hero-subtitle{margin-bottom:var(--spacing-md)}.cta-container{flex-direction:column;align-items:center}.cta-button{width:100%;max-width:280px}.intro-text h2{font-size:clamp(20px,5vw,32px)}}@media (max-width: 480px){.nav-links{display:none}.logo{margin:0 auto}}@media (min-width: 1920px){.nav-container{max-width:1400px}.hero-content{max-width:1000px}}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}}*:focus-visible{outline:2px solid var(--color-brand-blue);outline-offset:4px}img,video{max-width:100%;height:auto}