/* ===== 基础 ===== */
html{scroll-behavior:smooth}
body{-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
section{scroll-margin-top:5rem}
::selection{background:#FF6A00;color:#fff}

/* ===== 滚动显现动画(仅在JS启用时生效,保证无JS/爬虫可读) ===== */
.js .reveal{opacity:0;transform:translateY(28px);transition:opacity .8s cubic-bezier(.22,1,.36,1),transform .8s cubic-bezier(.22,1,.36,1)}
.js .reveal.in{opacity:1;transform:none}
.js .reveal-d1{transition-delay:.1s}.js .reveal-d2{transition-delay:.2s}
.js .reveal-d3{transition-delay:.3s}.js .reveal-d4{transition-delay:.4s}
@media (prefers-reduced-motion:reduce){
  .js .reveal{opacity:1;transform:none;transition:none}
  .marquee-track{animation:none!important}
  html{scroll-behavior:auto}
}

/* ===== 文字与背景装饰 ===== */
.text-brand{background:#FF8533;-webkit-background-clip:text;background-clip:text;color:transparent}
.text-gradient{background:linear-gradient(100deg,#FF8533 0%,#FF6A00 45%,#19C3D6 100%);-webkit-background-clip:text;background-clip:text;color:transparent}
.bg-grid-dark{background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);background-size:56px 56px}
.bg-grid-light{background-image:linear-gradient(rgba(22,22,31,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(22,22,31,.05) 1px,transparent 1px);background-size:56px 56px}
.hero-glow{background:radial-gradient(ellipse 60% 45% at 72% 16%,rgba(255,106,0,.13),transparent 65%),radial-gradient(ellipse 45% 40% at 12% 84%,rgba(25,195,214,.10),transparent 60%)}
.eyebrow{letter-spacing:.35em}

/* ===== 跑马灯 ===== */
.marquee{overflow:hidden;-webkit-mask-image:linear-gradient(90deg,transparent,#000 8%,#000 92%,transparent);mask-image:linear-gradient(90deg,transparent,#000 8%,#000 92%,transparent)}
.marquee-track{display:flex;width:max-content;animation:marquee 36s linear infinite}
.marquee-track.fast{animation-duration:28s}
.marquee:hover .marquee-track{animation-play-state:paused}
@keyframes marquee{from{transform:translateX(0)}to{transform:translateX(-50%)}}

/* ===== Hero AI 卡片 ===== */
.typing-caret::after{content:'▍';margin-left:2px;color:#FF6A00;animation:caret 1s steps(1) infinite}
@keyframes caret{50%{opacity:0}}
.float-slow{animation:floaty 7s ease-in-out infinite}
.float-slower{animation:floaty 9s ease-in-out infinite reverse}
@keyframes floaty{0%,100%{transform:translateY(0)}50%{transform:translateY(-14px)}}
.ring-orbit{animation:spin 40s linear infinite}
@keyframes spin{to{transform:rotate(360deg)}}

/* ===== 六维链路步骤 ===== */
.step-btn{transition:all .35s ease}
.step-btn .step-bar{transition:all .35s ease}
.step-panel{display:none}
.step-panel.active{display:block;animation:panelIn .5s cubic-bezier(.22,1,.36,1)}
@keyframes panelIn{from{opacity:0;transform:translateY(14px)}to{opacity:1;transform:none}}

/* ===== FAQ ===== */
.faq-a{display:grid;grid-template-rows:0fr;transition:grid-template-rows .45s cubic-bezier(.22,1,.36,1)}
.faq-item[data-open="true"] .faq-a{grid-template-rows:1fr}
.faq-item[data-open="true"] .faq-icon{transform:rotate(45deg)}
.faq-icon{transition:transform .35s ease}

/* ===== 其他 ===== */
.nav-link{position:relative}
.nav-link::after{content:'';position:absolute;left:0;bottom:-4px;width:0;height:2px;background:#FF6A00;transition:width .3s ease}
.nav-link:hover::after{width:100%}
#site-header.scrolled{background:rgba(255,255,255,.86);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid rgba(22,22,31,.07);box-shadow:0 8px 28px -16px rgba(22,22,31,.10)}
.price-toggle{transition:all .3s ease}
.logo-chip{filter:grayscale(1);opacity:.65;transition:all .35s ease}
.logo-chip:hover{filter:grayscale(0);opacity:1}
#back-top{opacity:0;pointer-events:none;transition:all .4s ease}
#back-top.show{opacity:1;pointer-events:auto}