/* ==========================================================================
   凡辰科技 FINECHEN — design tokens & styles
   纯静态、零外部依赖：无远程字体、无 CSS 框架、无统计脚本。
   ========================================================================== */

:root{
  /* 色板 —— 暗色科技（近黑底 + 青绿主色 + 电蓝辅色） */
  --bg:            #05070c;
  --bg-elevated:   #0a0e17;
  --bg-deep:       #030408;

  --text:          #e9eef7;
  --text-soft:     #b9c4d4;
  --muted:         #8794a8;

  --accent:        #2fd6c2;
  --accent-deep:   #17a795;
  --accent-2:      #4d7cff;

  --line:          rgba(255,255,255,.08);
  --line-strong:   rgba(255,255,255,.14);
  --surface:       rgba(255,255,255,.028);
  --surface-hover: rgba(255,255,255,.05);
  --accent-a08:    rgba(47,214,194,.08);
  --accent-a20:    rgba(47,214,194,.20);

  /* 排版 */
  --font-sans: "PingFang SC","HarmonyOS Sans SC","Microsoft YaHei","Noto Sans SC",
               system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;
  --font-mono: ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;

  /* 尺度 */
  --container: 1180px;
  --gutter: clamp(20px, 5vw, 40px);
  --radius: 14px;
  --radius-lg: 20px;
  --section-y: clamp(72px, 11vw, 148px);
  --nav-h: 68px;

  --ease: cubic-bezier(.22,.61,.36,1);
  --ease-out: cubic-bezier(.16,1,.3,1);
}

/* ---------- reset ---------- */
*,*::before,*::after{ box-sizing:border-box; }
html{ -webkit-text-size-adjust:100%; scroll-behavior:smooth; }
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  overflow-x:hidden;
}
h1,h2,h3,h4,p,ul,ol,figure{ margin:0; }
ul,ol{ padding:0; list-style:none; }
a{ color:inherit; text-decoration:none; }
img,svg{ display:block; max-width:100%; }
button,input,textarea,select{ font:inherit; color:inherit; }
strong{ color:var(--text); font-weight:600; }

/* Lenis 接管滚动时避免与原生平滑滚动打架 */
html.lenis,html.lenis body{ height:auto; }
html.lenis{ scroll-behavior:auto; }
.lenis.lenis-smooth{ scroll-behavior:auto !important; }

::selection{ background:var(--accent-a20); color:#fff; }

:focus-visible{
  outline:2px solid var(--accent);
  outline-offset:3px;
  border-radius:4px;
}

.sr-only{
  position:absolute; width:1px; height:1px; padding:0; margin:-1px;
  overflow:hidden; clip:rect(0 0 0 0); white-space:nowrap; border:0;
}
.skip-link{
  position:fixed; top:-100px; left:16px; z-index:200;
  background:var(--accent); color:#04120f; font-weight:600;
  padding:10px 18px; border-radius:0 0 10px 10px;
  transition:top .2s var(--ease);
}
.skip-link:focus{ top:0; }

/* ==========================================================================
   WebGL 环境层
   ========================================================================== */
/* 无 WebGL / JS 失败时依然成立的兜底画面（放在 body::before，独立于 canvas 透明度） */
body::before{
  content:""; position:fixed; inset:0; z-index:-1; pointer-events:none;
  background:
    radial-gradient(1100px 620px at 78% 12%, rgba(47,214,194,.10), transparent 62%),
    radial-gradient(900px 700px at 12% 78%, rgba(77,124,255,.09), transparent 60%),
    var(--bg);
}
#gl{
  position:fixed; inset:0; width:100%; height:100%;
  z-index:0; display:block;
  /* 首帧渲染完成后由 JS 加 .is-ready，CSS 负责淡入 */
  opacity:0;
  transition:opacity 1.6s ease;
}
#gl.is-ready{ opacity:1; }
canvas#gl.is-hidden{ display:none; }

.atmosphere{
  /* 只压顶/底边缘保证导航与页脚可读，中部留给 WebGL 粒子场 */
  position:fixed; inset:0; z-index:1; pointer-events:none;
  background:
    linear-gradient(180deg, rgba(5,7,12,.44) 0%, rgba(5,7,12,0) 15%, rgba(5,7,12,0) 60%, rgba(5,7,12,.58) 100%),
    radial-gradient(130% 72% at 50% 50%, rgba(5,7,12,0) 60%, rgba(5,7,12,.30) 100%);
}
.grain{
  position:fixed; inset:0; z-index:2; pointer-events:none; opacity:.035;
  mix-blend-mode:overlay;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ==========================================================================
   通用布局
   ========================================================================== */
.container{
  width:100%; max-width:var(--container);
  margin-inline:auto; padding-inline:var(--gutter);
  position:relative;
}
.container--narrow{ max-width:860px; }

.section{ position:relative; z-index:3; padding-block:var(--section-y); }
.section--alt{ background:linear-gradient(180deg, transparent, rgba(255,255,255,.012) 18%, rgba(255,255,255,.012) 82%, transparent); }

.section__head{
  display:grid; grid-template-columns:auto 1fr; gap:clamp(18px,4vw,56px);
  align-items:start; margin-bottom:clamp(40px,6vw,72px);
}
.section__head--stack{ grid-template-columns:auto 1fr; }
.section__no{
  font-family:var(--font-mono); font-size:12px; letter-spacing:.16em;
  color:var(--accent); padding-top:9px; opacity:.85;
}

.eyebrow{
  font-family:var(--font-mono); font-size:11px; font-weight:500;
  letter-spacing:.24em; text-transform:uppercase;
  color:var(--accent); margin-bottom:18px;
}

.display{
  font-size:clamp(2.5rem, 8.2vw, 5.6rem);
  line-height:1.03; font-weight:700; letter-spacing:-.035em;
}
.h2{
  font-size:clamp(1.6rem, 3.9vw, 2.85rem);
  line-height:1.16; font-weight:650; letter-spacing:-.025em;
  max-width:22ch;
}
.h2--xl{ font-size:clamp(1.9rem, 4.6vw, 3.4rem); max-width:20ch; }

.lede{
  margin-top:20px; max-width:56ch;
  color:var(--text-soft); font-size:clamp(1rem,1.35vw,1.09rem); line-height:1.75;
}

/* ==========================================================================
   按钮
   ========================================================================== */
.btn{
  --btn-py:12px; --btn-px:22px;
  display:inline-flex; align-items:center; justify-content:center; gap:8px;
  padding:var(--btn-py) var(--btn-px);
  border-radius:100px; border:1px solid transparent;
  font-size:.94rem; font-weight:600; letter-spacing:.01em;
  cursor:pointer; white-space:nowrap;
  transition:background-color .25s var(--ease), border-color .25s var(--ease),
             color .25s var(--ease), transform .25s var(--ease), box-shadow .25s var(--ease);
  will-change:transform;
}
.btn--sm{ --btn-py:9px; --btn-px:18px; font-size:.875rem; }
.btn--lg{ --btn-py:15px; --btn-px:30px; font-size:1rem; }
.btn--block{ width:100%; }

.btn--primary{
  background:var(--accent); color:#04120f;
  box-shadow:0 0 0 1px rgba(47,214,194,.35), 0 10px 34px -14px rgba(47,214,194,.55);
}
.btn--primary:hover{
  background:#4ce6d3;
  box-shadow:0 0 0 1px rgba(47,214,194,.5), 0 16px 42px -14px rgba(47,214,194,.7);
}
.btn--ghost{
  background:rgba(255,255,255,.045); color:var(--text);
  border-color:var(--line-strong); backdrop-filter:blur(6px);
}
.btn--ghost:hover{ background:rgba(255,255,255,.09); border-color:rgba(255,255,255,.24); }
.btn__arrow{ width:16px; height:16px; transition:transform .3s var(--ease-out); }
.btn--ghost:hover .btn__arrow{ transform:translateX(3px); }

/* ==========================================================================
   进度条 & 导航
   ========================================================================== */
.progress{
  position:fixed; top:0; left:0; right:0; height:2px; z-index:120;
  background:transparent; pointer-events:none;
}
.progress__bar{
  display:block; height:100%; width:0%;
  background:linear-gradient(90deg, var(--accent), var(--accent-2));
  transform-origin:0 50%;
}

.nav{
  position:fixed; top:0; left:0; right:0; z-index:100;
  height:var(--nav-h);
  transition:background-color .35s var(--ease), border-color .35s var(--ease), backdrop-filter .35s var(--ease);
  border-bottom:1px solid transparent;
}
.nav.is-scrolled{
  background:rgba(5,7,12,.72);
  border-bottom-color:var(--line);
  backdrop-filter:blur(16px) saturate(1.2);
}
.nav__inner{
  max-width:var(--container); margin-inline:auto; padding-inline:var(--gutter);
  height:100%; display:flex; align-items:center; justify-content:space-between; gap:24px;
}

.brand{ display:inline-flex; align-items:center; gap:10px; }
.brand__mark{ width:26px; height:26px; color:var(--accent); flex:none; }
.brand__mark svg{ width:100%; height:100%; }
.brand__text{
  font-size:1.12rem; font-weight:700; letter-spacing:.08em;
}

.nav__links{ display:flex; align-items:center; gap:6px; }
.nav__link{
  position:relative; padding:8px 13px; border-radius:8px;
  font-size:.9rem; color:var(--text-soft);
  transition:color .22s var(--ease), background-color .22s var(--ease);
}
.nav__link:hover{ color:var(--text); background:var(--surface-hover); }
.nav__link.is-active{ color:var(--text); }
.nav__link.is-active::after{
  content:""; position:absolute; left:13px; right:13px; bottom:2px; height:1.5px;
  background:var(--accent); border-radius:2px;
}
.nav__mobile-cta{ display:none; }

.nav__actions{ display:flex; align-items:center; gap:14px; }
.nav__ghost{ font-size:.9rem; color:var(--text-soft); transition:color .2s var(--ease); }
.nav__ghost:hover{ color:var(--text); }

.nav__burger{
  display:none; width:40px; height:40px; border:1px solid var(--line-strong);
  background:var(--surface); border-radius:10px; cursor:pointer;
  position:relative;
}
.nav__burger span{
  position:absolute; left:11px; right:11px; height:1.5px; background:var(--text);
  transition:transform .3s var(--ease), opacity .2s var(--ease);
}
.nav__burger span:nth-child(1){ top:15px; }
.nav__burger span:nth-child(2){ bottom:15px; }
.nav__burger[aria-expanded="true"] span:nth-child(1){ transform:translateY(4.5px) rotate(45deg); }
.nav__burger[aria-expanded="true"] span:nth-child(2){ transform:translateY(-4.5px) rotate(-45deg); }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero{
  position:relative; z-index:3;
  min-height:100svh; display:flex; align-items:center;
  padding-top:calc(var(--nav-h) + 6vh); padding-bottom:12vh;
}
.hero__inner{ max-width:940px; }
.hero__title{ margin-bottom:clamp(22px,3.2vw,34px); }
.hero__title .line{ display:block; }
.hero__title .char{
  display:inline-block; opacity:0; transform:translateY(.42em) rotate(3deg);
  filter:blur(6px);
}
html:not(.js) .hero__title .char{ opacity:1; transform:none; filter:none; }

.hero__sub{
  max-width:52ch; color:var(--text-soft);
  font-size:clamp(1rem,1.5vw,1.14rem); line-height:1.78;
}
.hero__sub strong{ color:var(--text); }

.hero__cta{ display:flex; flex-wrap:wrap; gap:12px; margin-top:clamp(28px,4vw,40px); }

.hero__meta{
  display:flex; flex-wrap:wrap; gap:10px 28px;
  margin-top:clamp(30px,4.5vw,44px); padding-top:22px;
  border-top:1px solid var(--line);
  font-family:var(--font-mono); font-size:.78rem; letter-spacing:.05em; color:var(--muted);
}
.hero__meta li{ display:flex; align-items:center; gap:9px; }
.hero__meta li::before{
  content:""; width:5px; height:5px; border-radius:50%;
  background:var(--accent); flex:none;
}

.hero__scroll{
  position:absolute; left:var(--gutter); bottom:34px;
  display:flex; align-items:center; gap:12px;
}
.hero__scroll-text{
  font-family:var(--font-mono); font-size:10px; letter-spacing:.24em; color:var(--muted);
}
.hero__scroll-line{ width:52px; height:1px; background:var(--line-strong); position:relative; overflow:hidden; }
.hero__scroll-line::after{
  content:""; position:absolute; inset:0; background:var(--accent);
  transform-origin:0 50%; animation:scrollHint 2.6s var(--ease) infinite;
}
@keyframes scrollHint{
  0%{ transform:translateX(-100%); }
  55%,100%{ transform:translateX(100%); }
}

/* ==========================================================================
   跑马灯
   ========================================================================== */
.marquee-section{
  position:relative; z-index:3;
  padding-block:26px; border-block:1px solid var(--line);
  background:rgba(5,7,12,.42); overflow:hidden;
}
.marquee{ overflow:hidden; -webkit-mask-image:linear-gradient(90deg,transparent,#000 12%,#000 88%,transparent);
          mask-image:linear-gradient(90deg,transparent,#000 12%,#000 88%,transparent); }
.marquee__track{
  display:flex; align-items:center; gap:26px; width:max-content;
  animation:marquee 46s linear infinite;
}
.marquee__track span{
  font-family:var(--font-mono); font-size:.8rem; letter-spacing:.14em;
  color:var(--muted); white-space:nowrap; text-transform:uppercase;
}
.marquee__track .dot{ color:var(--accent); opacity:.6; }
@keyframes marquee{ to{ transform:translateX(-50%); } }

/* ==========================================================================
   卡片 / 网格
   ========================================================================== */
.grid{ display:grid; gap:clamp(14px,2vw,20px); }
.grid--2{ grid-template-columns:repeat(2,1fr); }

.card{
  position:relative; padding:clamp(24px,3vw,34px);
  border:1px solid var(--line); border-radius:var(--radius-lg);
  background:linear-gradient(180deg, rgba(255,255,255,.035), rgba(255,255,255,.012));
  backdrop-filter:blur(10px);
  overflow:hidden;
  transition:border-color .35s var(--ease), background-color .35s var(--ease), transform .4s var(--ease-out);
}
.card::after{
  content:""; position:absolute; inset:0; border-radius:inherit; pointer-events:none;
  background:radial-gradient(420px 200px at 50% -30%, var(--accent-a08), transparent 70%);
  opacity:0; transition:opacity .45s var(--ease);
}
.card:hover{ border-color:var(--line-strong); transform:translateY(-3px); }
.card:hover::after{ opacity:1; }

.card__icon{
  width:42px; height:42px; border-radius:11px;
  display:grid; place-items:center; margin-bottom:22px;
  border:1px solid var(--accent-a20); background:var(--accent-a08); color:var(--accent);
}
.card__icon svg{ width:22px; height:22px; }
.card__title{ font-size:1.16rem; font-weight:650; letter-spacing:-.015em; }
.card__text{ margin-top:12px; color:var(--text-soft); font-size:.95rem; line-height:1.72; }
.card__list{ margin-top:20px; display:flex; flex-direction:column; gap:9px; }
.card__list li{
  position:relative; padding-left:19px;
  font-size:.875rem; color:var(--muted);
}
.card__list li::before{
  content:""; position:absolute; left:0; top:.62em;
  width:7px; height:1.5px; background:var(--accent); opacity:.75;
}

/* ==========================================================================
   流程
   ========================================================================== */
.steps{ display:grid; grid-template-columns:repeat(3,1fr); gap:clamp(14px,2vw,20px); }
.step{
  position:relative; padding:clamp(24px,3vw,32px);
  border:1px solid var(--line); border-radius:var(--radius-lg);
  background:linear-gradient(180deg, rgba(255,255,255,.032), rgba(255,255,255,.01));
  backdrop-filter:blur(10px);
  transition:border-color .35s var(--ease), transform .4s var(--ease-out);
}
.step:hover{ border-color:var(--line-strong); transform:translateY(-3px); }
.step__no{
  font-family:var(--font-mono); font-size:11px; letter-spacing:.18em;
  color:var(--accent); opacity:.9;
}
.step__title{ margin-top:16px; font-size:1.24rem; font-weight:650; letter-spacing:-.015em; }
.step__text{ margin-top:10px; color:var(--text-soft); font-size:.93rem; line-height:1.72; }
.step__code{
  display:block; margin-top:22px; padding:11px 14px;
  border-radius:9px; border:1px solid var(--line);
  background:rgba(0,0,0,.35);
  font-family:var(--font-mono); font-size:.78rem; color:var(--accent);
  overflow-x:auto; white-space:nowrap;
}

/* ==========================================================================
   指标
   ========================================================================== */
.section--metrics{ padding-block:clamp(56px,7vw,88px); }
.metrics__note{
  font-family:var(--font-mono); font-size:.74rem; letter-spacing:.06em;
  color:var(--muted); opacity:.75; margin-bottom:30px;
}
.metrics{
  display:grid; grid-template-columns:repeat(4,1fr);
  gap:1px; background:var(--line);
  border:1px solid var(--line); border-radius:var(--radius); overflow:hidden;
}
.metric{
  background:rgba(8,11,19,.72); padding:clamp(24px,3vw,34px);
  backdrop-filter:blur(8px);
}
.metric__value{
  display:flex; align-items:baseline; gap:4px;
  font-size:clamp(1.9rem,4vw,2.9rem); font-weight:700; letter-spacing:-.035em;
  color:var(--text); font-variant-numeric:tabular-nums;
}
.metric__unit{ font-size:.95rem; font-weight:600; color:var(--accent); letter-spacing:0; }
.metric__label{ margin-top:12px; font-size:.83rem; color:var(--muted); line-height:1.6; }

/* ==========================================================================
   场景
   ========================================================================== */
.cases{ display:grid; grid-template-columns:repeat(3,1fr); gap:clamp(14px,2vw,20px); }
.case{
  padding:clamp(24px,3vw,32px);
  border:1px solid var(--line); border-radius:var(--radius-lg);
  background:linear-gradient(180deg, rgba(255,255,255,.032), rgba(255,255,255,.01));
  backdrop-filter:blur(10px);
  display:flex; flex-direction:column;
  transition:border-color .35s var(--ease), transform .4s var(--ease-out);
}
.case:hover{ border-color:var(--line-strong); transform:translateY(-3px); }
.case__tag{
  font-family:var(--font-mono); font-size:.72rem; letter-spacing:.1em;
  color:var(--accent); text-transform:uppercase;
}
.case__title{ margin-top:16px; font-size:1.1rem; font-weight:650; line-height:1.45; letter-spacing:-.015em; }
.case__text{ margin-top:12px; color:var(--text-soft); font-size:.92rem; line-height:1.72; flex:1; }
.case__result{
  margin-top:22px; padding-top:18px; border-top:1px solid var(--line);
  font-size:.83rem; color:var(--muted);
}
.case__result strong{ color:var(--accent); font-weight:600; margin-right:8px; }

/* ==========================================================================
   定价
   ========================================================================== */
.plans{ display:grid; grid-template-columns:repeat(3,1fr); gap:clamp(14px,2vw,20px); align-items:start; }
.plan{
  position:relative; padding:clamp(26px,3vw,34px);
  border:1px solid var(--line); border-radius:var(--radius-lg);
  background:linear-gradient(180deg, rgba(255,255,255,.032), rgba(255,255,255,.01));
  backdrop-filter:blur(10px);
  transition:border-color .35s var(--ease), transform .4s var(--ease-out);
}
.plan:hover{ border-color:var(--line-strong); transform:translateY(-3px); }
.plan--featured{
  border-color:var(--accent-a20);
  background:
    radial-gradient(520px 220px at 50% -12%, rgba(47,214,194,.11), transparent 68%),
    linear-gradient(180deg, rgba(255,255,255,.05), rgba(255,255,255,.014));
  box-shadow:0 30px 70px -46px rgba(47,214,194,.6);
}
.plan__badge{
  position:absolute; top:-11px; left:clamp(26px,3vw,34px);
  padding:4px 12px; border-radius:100px;
  background:var(--accent); color:#04120f;
  font-size:.7rem; font-weight:700; letter-spacing:.06em;
}
.plan__name{ font-size:1.02rem; font-weight:650; letter-spacing:.01em; }
.plan__price{ margin-top:16px; display:flex; align-items:baseline; gap:10px; flex-wrap:wrap; }
.plan__amount{ font-size:clamp(1.8rem,3.4vw,2.3rem); font-weight:700; letter-spacing:-.035em; }
.plan__cycle{
  font-family:var(--font-mono); font-size:.74rem; letter-spacing:.06em; color:var(--muted);
}
.plan__desc{ margin-top:12px; font-size:.88rem; color:var(--muted); line-height:1.65; min-height:2.9em; }
.plan .btn{ margin-top:24px; }
.plan__features{
  margin-top:26px; padding-top:24px; border-top:1px solid var(--line);
  display:flex; flex-direction:column; gap:12px;
}
.plan__features li{
  position:relative; padding-left:24px;
  font-size:.885rem; color:var(--text-soft); line-height:1.6;
}
.plan__features li::before{
  content:""; position:absolute; left:2px; top:.52em;
  width:11px; height:6px;
  border-left:1.5px solid var(--accent); border-bottom:1.5px solid var(--accent);
  transform:rotate(-45deg);
}

/* ==========================================================================
   FAQ
   ========================================================================== */
.faq{ display:flex; flex-direction:column; gap:10px; }
.faq__item{
  border:1px solid var(--line); border-radius:var(--radius);
  background:rgba(255,255,255,.022);
  overflow:hidden;
  transition:border-color .3s var(--ease), background-color .3s var(--ease);
}
.faq__item[open]{ border-color:var(--line-strong); background:rgba(255,255,255,.04); }
.faq__item summary{
  display:flex; align-items:center; justify-content:space-between; gap:18px;
  padding:20px clamp(20px,2.6vw,26px);
  cursor:pointer; list-style:none;
  font-size:1rem; font-weight:550; letter-spacing:-.01em;
  transition:color .2s var(--ease);
}
.faq__item summary::-webkit-details-marker{ display:none; }
.faq__item summary::after{
  content:""; flex:none; width:11px; height:11px;
  border-right:1.5px solid var(--accent); border-bottom:1.5px solid var(--accent);
  transform:rotate(45deg) translateY(-2px);
  transition:transform .32s var(--ease);
}
.faq__item[open] summary::after{ transform:rotate(-135deg) translateY(-2px); }
.faq__item summary:hover{ color:#fff; }
.faq__body{ padding:0 clamp(20px,2.6vw,26px) 22px; }
.faq__body p{ color:var(--text-soft); font-size:.93rem; line-height:1.78; max-width:64ch; }

/* ==========================================================================
   CTA + 表单
   ========================================================================== */
.section--cta{ padding-block:var(--section-y); }
.cta{
  display:grid; grid-template-columns:1.05fr .95fr;
  gap:clamp(30px,5vw,68px); align-items:start;
  padding:clamp(30px,5vw,60px);
  border:1px solid var(--line); border-radius:26px;
  background:
    radial-gradient(700px 320px at 8% 0%, rgba(47,214,194,.09), transparent 62%),
    radial-gradient(600px 340px at 96% 100%, rgba(77,124,255,.09), transparent 62%),
    rgba(255,255,255,.022);
  backdrop-filter:blur(12px);
}
.cta__mail{ margin-top:26px; }
.cta__mail a{
  font-family:var(--font-mono); font-size:.92rem; color:var(--accent);
  border-bottom:1px solid var(--accent-a20); padding-bottom:2px;
  transition:border-color .25s var(--ease);
}
.cta__mail a:hover{ border-bottom-color:var(--accent); }

.form{ display:flex; flex-direction:column; gap:14px; }
.form__row{ display:grid; grid-template-columns:1fr 1fr; gap:14px; }
.field{ display:flex; flex-direction:column; gap:8px; }
.field__label{
  font-family:var(--font-mono); font-size:.72rem; letter-spacing:.1em;
  color:var(--muted); text-transform:uppercase;
}
.field input,.field textarea{
  width:100%; padding:12px 14px;
  border:1px solid var(--line-strong); border-radius:10px;
  background:rgba(0,0,0,.3);
  font-size:.93rem; line-height:1.6;
  transition:border-color .25s var(--ease), background-color .25s var(--ease);
  resize:vertical;
}
.field input::placeholder,.field textarea::placeholder{ color:#5d6a7d; }
.field input:hover,.field textarea:hover{ border-color:rgba(255,255,255,.22); }
.field input:focus,.field textarea:focus{
  outline:none; border-color:var(--accent); background:rgba(0,0,0,.45);
  box-shadow:0 0 0 3px var(--accent-a08);
}
.field.has-error input,.field.has-error textarea{ border-color:#ff7a7a; }
.form__hint{ font-size:.79rem; color:var(--muted); line-height:1.6; }
.form__hint.is-ok{ color:var(--accent); }
.form__hint.is-err{ color:#ff9a9a; }
.form .btn{ margin-top:6px; }

/* ==========================================================================
   页脚
   ========================================================================== */
.footer{
  position:relative; z-index:3;
  border-top:1px solid var(--line);
  background:linear-gradient(180deg, rgba(3,4,8,.6), rgba(3,4,8,.95));
  padding-top:clamp(48px,6vw,72px);
}
.footer__inner{
  display:grid; grid-template-columns:1.2fr 2fr; gap:clamp(30px,5vw,60px);
  padding-bottom:clamp(36px,5vw,56px);
}
.footer__desc{ margin-top:18px; color:var(--muted); font-size:.9rem; max-width:34ch; }
.footer__mail{
  display:inline-block; margin-top:16px;
  font-family:var(--font-mono); font-size:.85rem; color:var(--accent);
}
.footer__cols{ display:grid; grid-template-columns:repeat(3,1fr); gap:24px; }
.footer__col{ display:flex; flex-direction:column; gap:11px; }
.footer__col h4{
  font-family:var(--font-mono); font-size:.72rem; letter-spacing:.12em;
  color:var(--muted); text-transform:uppercase; margin-bottom:3px;
}
.footer__col a{ font-size:.9rem; color:var(--text-soft); transition:color .2s var(--ease); }
.footer__col a:hover{ color:var(--accent); }

.footer__bottom{
  display:flex; flex-wrap:wrap; gap:12px 30px; align-items:center; justify-content:space-between;
  padding-block:24px; border-top:1px solid var(--line);
  font-size:.79rem; color:var(--muted);
}
.footer__legal{ max-width:62ch; }

/* ==========================================================================
   入场动画（仅在 JS 可用时隐藏初始状态，保证无 JS 也能读）
   ========================================================================== */
html.js [data-reveal]{ opacity:0; transform:translateY(22px); }
html.js [data-card]{ opacity:0; transform:translateY(26px); }

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width:1024px){
  .grid--2{ grid-template-columns:1fr 1fr; }
  .steps,.cases,.plans{ grid-template-columns:1fr; }
  .metrics{ grid-template-columns:repeat(2,1fr); }
  .cta{ grid-template-columns:1fr; }
  .plan__desc{ min-height:0; }
  .footer__inner{ grid-template-columns:1fr; }
}

@media (max-width:860px){
  :root{ --nav-h:60px; }

  .nav__links{
    position:fixed; top:var(--nav-h); left:0; right:0;
    flex-direction:column; align-items:stretch; gap:2px;
    padding:16px var(--gutter) 26px;
    background:rgba(5,7,12,.96);
    border-bottom:1px solid var(--line);
    backdrop-filter:blur(18px);
    transform:translateY(-12px); opacity:0; visibility:hidden;
    transition:opacity .28s var(--ease), transform .28s var(--ease), visibility .28s;
    max-height:calc(100svh - var(--nav-h)); overflow-y:auto;
  }
  .nav__links.is-open{ transform:none; opacity:1; visibility:visible; }
  .nav__link{ padding:14px 4px; font-size:1rem; border-bottom:1px solid var(--line); border-radius:0; }
  .nav__link.is-active::after{ display:none; }
  .nav__mobile-cta{ display:block; margin-top:18px; }

  .nav__ghost{ display:none; }
  .nav__actions .btn--sm{ display:none; }
  .nav__burger{ display:block; }

  .grid--2{ grid-template-columns:1fr; }
  .form__row{ grid-template-columns:1fr; }
  .footer__cols{ grid-template-columns:1fr 1fr; }

  .hero{ min-height:auto; padding-top:calc(var(--nav-h) + 14vh); padding-bottom:14vh; }
  .hero__scroll{ display:none; }
  .section__head{ grid-template-columns:1fr; gap:14px; }
  .section__no{ padding-top:0; }
  .h2{ max-width:none; }
  .h2--xl{ max-width:none; }
}

@media (max-width:520px){
  .metrics{ grid-template-columns:1fr; }
  .hero__cta{ flex-direction:column; align-items:stretch; }
  .hero__cta .btn{ width:100%; }
  .footer__cols{ grid-template-columns:1fr; }
  .footer__bottom{ flex-direction:column; align-items:flex-start; }
}

/* 触摸设备：不做 hover 位移，避免点击时抖动 */
@media (hover:none){
  .card:hover,.step:hover,.case:hover,.plan:hover{ transform:none; }
}

/* ==========================================================================
   无障碍：尊重系统「减少动态效果」
   ========================================================================== */
@media (prefers-reduced-motion: reduce){
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .marquee__track{ animation:none; }
  .hero__scroll-line::after{ display:none; }
  html.js [data-reveal],
  html.js [data-card]{ opacity:1; transform:none; }
  .hero__title .char{ opacity:1; transform:none; filter:none; }
  .card:hover,.step:hover,.case:hover,.plan:hover{ transform:none; }
}

/* 强制高对比模式 */
@media (prefers-contrast: more){
  :root{ --text-soft:#d6deea; --muted:#aab6c7; --line:rgba(255,255,255,.2); }
}