/* =========================================================================
   简幻欢 SimpFun — 苹果官网风格（全亮 · 堆叠圆角分屏）
   ========================================================================= */

:root{
  --bg:#ffffff;
  --grey:#f5f5f7;
  --ink:#1d1d1f;
  --ink-2:#6e6e73;
  --ink-3:#86868b;
  --blue:#0071e3;
  --link:#0066cc;
  --g1:#0a84ff;
  --g2:#7a5cff;
  --maxw:1024px;
  --maxw-wide:1100px;
  --nav-h:48px;
  --radius:22px;
  --panel-r:48px;
  --ease:cubic-bezier(.28,.11,.32,1);
  --ease-out:cubic-bezier(.16,1,.3,1);
}

*,*::before,*::after{ box-sizing:border-box; }
html{ -webkit-text-size-adjust:100%; scroll-behavior:smooth; scroll-snap-type:y mandatory; }
body{
  margin:0; background:var(--bg); color:var(--ink); line-height:1.47;
  font-family:"PingFang SC",-apple-system,BlinkMacSystemFont,"SF Pro Display","SF Pro Text","Helvetica Neue","Microsoft YaHei",system-ui,sans-serif;
  -webkit-font-smoothing:antialiased; text-rendering:optimizeLegibility; overflow-x:hidden;
}
a{ color:inherit; text-decoration:none; }
img{ display:block; max-width:100%; }
::selection{ background:rgba(10,132,255,.16); }

/* ---------- 文字基元 ---------- */
.eyebrow{ font-size:clamp(14px,1.8vw,19px); font-weight:600; letter-spacing:.004em; color:var(--ink-3); margin:0 0 .7em; }
.h-section{ font-size:clamp(32px,5vw,56px); line-height:1.1; font-weight:600; letter-spacing:-.015em; margin:0; color:var(--ink); }
.muted{ color:var(--ink-2); }
.lead{ font-size:clamp(17px,2.1vw,22px); line-height:1.5; color:var(--ink-2); margin:1.1em auto 0; max-width:48ch; }
.g-text{ background:linear-gradient(115deg,var(--g1) 8%, var(--g2) 92%); -webkit-background-clip:text; background-clip:text; color:transparent; }

/* =========================================================================
   导航（浅色磨砂品牌条）
   ========================================================================= */
.nav{ position:fixed; inset:0 0 auto 0; z-index:1000; height:var(--nav-h);
  background:rgba(255,255,255,.72); -webkit-backdrop-filter:saturate(180%) blur(20px); backdrop-filter:saturate(180%) blur(20px);
  border-bottom:1px solid rgba(0,0,0,0); transition:background .3s, border-color .3s; }
.nav.is-scrolled{ background:rgba(255,255,255,.86); border-bottom-color:rgba(0,0,0,.08); }
.nav__inner{ max-width:var(--maxw-wide); height:100%; margin:0 auto; padding:0 22px; display:flex; align-items:center; justify-content:space-between; }
.nav__brand{ display:flex; align-items:center; gap:8px; color:var(--ink); font-weight:600; font-size:16px; }
.nav__brand img{ border-radius:6px; }
.nav__tag{ font-size:12.5px; color:var(--ink-3); letter-spacing:.02em; }

/* =========================================================================
   Hero
   ========================================================================= */
.hero{ position:relative; min-height:100svh; display:flex; align-items:center; justify-content:center; text-align:center;
  padding:var(--nav-h) 24px 0; background:#fff; scroll-snap-align:start; scroll-snap-stop:always; }
.hero__inner{ max-width:900px; }
.hero__mark{ width:56px; height:56px; border-radius:15px; margin:0 auto 28px;
  box-shadow:0 14px 34px -12px rgba(0,0,0,.28); animation:floaty 4.5s var(--ease) infinite alternate; }
.hero__mark--sm{ width:44px; height:44px; margin-bottom:22px; }
@keyframes floaty{ from{ transform:translateY(0); } to{ transform:translateY(-9px); } }
.hero__title{ font-size:clamp(46px,9.4vw,104px); line-height:1.04; font-weight:600; letter-spacing:-.025em; margin:.08em 0 .28em; color:var(--ink); white-space:nowrap; }
.hero__sub{ font-size:clamp(18px,2.7vw,27px); line-height:1.32; color:var(--ink-2); margin:0 auto; max-width:26ch; font-weight:400; }

/* 鼠标滚动指示 */
.scroll-ind{ position:absolute; bottom:62px; left:50%; transform:translateX(-50%); display:flex; flex-direction:column; align-items:center; gap:9px; opacity:.55; }
.mouse{ width:22px; height:34px; border:1.6px solid var(--ink-3); border-radius:12px; display:flex; justify-content:center; padding-top:6px; }
.mouse b{ width:3px; height:7px; border-radius:2px; background:var(--ink-3); animation:scrolldot 1.7s var(--ease) infinite; }
@keyframes scrolldot{ 0%{ transform:translateY(0); opacity:1; } 60%{ transform:translateY(8px); opacity:0; } 100%{ opacity:0; } }
.scroll-ind .chev{ width:8px; height:8px; border-right:1.6px solid var(--ink-3); border-bottom:1.6px solid var(--ink-3); transform:rotate(45deg); animation:bob 1.7s var(--ease) infinite; }
@keyframes bob{ 0%,100%{ transform:rotate(45deg) translate(0,0); } 50%{ transform:rotate(45deg) translate(2px,2px); } }

/* =========================================================================
   堆叠圆角分屏
   ========================================================================= */
.panel{ position:relative; min-height:100svh; display:flex; align-items:center; justify-content:center;
  padding:calc(var(--nav-h) + 7vh) 24px 9vh; scroll-snap-align:start; scroll-snap-stop:always; }
.panel--white{ background:#fff; }
.panel--grey{ background:var(--grey); }
.panel__inner{ width:100%; max-width:var(--maxw); margin:0 auto; text-align:center; }

/* 右侧翻页圆点 */
.dots{ position:fixed; right:20px; top:50%; transform:translateY(-50%); z-index:900; display:flex; flex-direction:column; gap:13px; }
.dots button{ width:8px; height:8px; padding:0; border:0; border-radius:50%; background:rgba(0,0,0,.2); cursor:pointer;
  transition:transform .35s var(--ease), background .35s var(--ease); }
.dots button:hover{ background:rgba(0,0,0,.42); transform:scale(1.2); }
.dots button.is-active{ background:var(--blue); transform:scale(1.4); }

/* 收尾页版权 */
.closing-copy{ position:absolute; left:0; right:0; bottom:28px; text-align:center; font-size:12px; color:var(--ink-3); margin:0; padding:0 24px; }

/* 实例卡 */
.hero__card{ margin:clamp(40px,6vh,72px) auto 0; width:min(460px,90vw); }
.instance{ background:#fff; border-radius:28px; padding:34px 36px; text-align:left;
  box-shadow:0 2px 1px rgba(0,0,0,.04), 0 30px 60px -28px rgba(0,0,0,.2); border:1px solid rgba(0,0,0,.05); }
.instance__tag{ font-size:13px; color:var(--ink-2); }
.instance__nums{ display:flex; align-items:center; justify-content:space-between; margin:24px 0 22px; }
.instance__nums > div{ flex:1; text-align:center; position:relative; }
.instance__nums > div + div::before{ content:""; position:absolute; left:0; top:14%; height:72%; width:1px; background:rgba(0,0,0,.08); }
.instance__nums b{ display:block; font-size:clamp(34px,7vw,46px); font-weight:600; letter-spacing:-.02em; line-height:1; color:var(--ink); }
.instance__nums b em{ font-style:normal; font-size:.5em; font-weight:500; color:var(--ink-2); }
.instance__nums span{ font-size:12.5px; color:var(--ink-2); }
.instance__foot{ display:flex; align-items:center; gap:9px; font-size:13px; color:var(--ink-2); padding-top:18px; border-top:1px solid rgba(0,0,0,.06); margin-top:4px; }
.live{ width:8px; height:8px; border-radius:50%; background:#34c759; box-shadow:0 0 8px rgba(52,199,89,.6); animation:pulse 2.4s var(--ease) infinite; }
@keyframes pulse{ 0%,100%{ opacity:1; } 50%{ opacity:.45; } }

/* 数据条 */
.stats{ display:flex; flex-wrap:wrap; justify-content:center; align-items:flex-end; gap:clamp(24px,5vw,64px); margin-top:clamp(40px,6vh,64px); }
.stat b{ display:block; font-size:clamp(30px,4.4vw,46px); font-weight:600; letter-spacing:-.02em; color:var(--ink); }
.stat b em{ font-style:normal; font-size:.5em; font-weight:600; color:var(--ink-2); }
.stat span{ font-size:14px; color:var(--ink-2); }
.stat--accent b{ color:var(--blue); }

/* =========================================================================
   卡片
   ========================================================================= */
.cards{ margin-top:clamp(46px,7vh,72px); display:grid; grid-template-columns:repeat(3,1fr); gap:20px; }
.card{ background:#fff; border-radius:var(--radius); padding:36px 30px; text-align:left; border:1px solid rgba(0,0,0,.06);
  box-shadow:0 18px 44px -30px rgba(0,0,0,.22); transition:transform .4s var(--ease), box-shadow .4s var(--ease); }
.card:hover{ transform:translateY(-5px); box-shadow:0 28px 56px -28px rgba(0,0,0,.26); }
.card__icon{ display:inline-block; width:42px; height:42px; background:var(--blue);
  -webkit-mask:var(--i) center/contain no-repeat; mask:var(--i) center/contain no-repeat; }
.card h3{ font-size:21px; font-weight:600; margin:20px 0 9px; letter-spacing:-.01em; }
.card p{ font-size:16px; line-height:1.55; color:var(--ink-2); margin:0; }
.card--stat b{ display:block; font-size:26px; font-weight:600; letter-spacing:-.01em; margin-bottom:9px; color:var(--ink); }
.card--stat span{ font-size:15px; line-height:1.55; color:var(--ink-2); }

[data-icon="bolt"]{--i:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M13 3 4 14h7l-1 7 9-11h-7z'/%3E%3C/svg%3E");}
[data-icon="rewind"]{--i:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M3 12a9 9 0 1 0 3-6.7'/%3E%3Cpath d='M3 4v4h4'/%3E%3Cpath d='M12 8v4l3 2'/%3E%3C/svg%3E");}
[data-icon="shield"]{--i:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M12 3l7 3v5c0 4-3 7-7 8-4-1-7-4-7-8V6z'/%3E%3Cpath d='M9 12l2 2 4-4'/%3E%3C/svg%3E");}
[data-icon="spark"]{--i:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M12 3l1.8 5.2L19 10l-5.2 1.8L12 17l-1.8-5.2L5 10l5.2-1.8z'/%3E%3Cpath d='M18.5 15l.6 1.8 1.9.7-1.9.7-.6 1.8-.6-1.8-1.9-.7 1.9-.7z'/%3E%3C/svg%3E");}
[data-icon="calendar"]{--i:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Crect x='4' y='5' width='16' height='16' rx='2'/%3E%3Cpath d='M4 9h16M8 3v4M16 3v4'/%3E%3C/svg%3E");}
[data-icon="sliders"]{--i:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23000' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M4 8h10M18 8h2M4 16h2M10 16h10'/%3E%3Ccircle cx='16' cy='8' r='2'/%3E%3Ccircle cx='8' cy='16' r='2'/%3E%3C/svg%3E");}

/* =========================================================================
   渐显
   ========================================================================= */
.reveal{ opacity:0; transform:translateY(30px) scale(.985); transition:opacity .9s var(--ease-out), transform .9s var(--ease-out); }
.reveal.is-visible{ opacity:1; transform:none; }
.cards .reveal{ transition-delay:var(--d,0s); }

/* =========================================================================
   响应式
   ========================================================================= */
@media (max-width:860px){
  .dots{ display:none; }
  .cards{ grid-template-columns:repeat(2,1fr); }
  .cards--3{ grid-template-columns:1fr; max-width:440px; margin-left:auto; margin-right:auto; }
}
@media (max-width:600px){
  .nav__tag{ display:none; }
  .cards{ grid-template-columns:1fr; max-width:420px; margin-left:auto; margin-right:auto; }
  .stats{ gap:20px 34px; }
}
@media (max-width:380px){ .hero__title{ white-space:normal; } }

@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{ animation-duration:.001ms !important; animation-iteration-count:1 !important; transition-duration:.001ms !important; scroll-behavior:auto !important; }
  .reveal{ opacity:1; transform:none; }
}