/* ===========================================================
   BATLINK — INDEX1 · "GLACIAL CORE"
   固定视口，滚轮驱动内部粒子编队变化；页面本身不滚动。
   =========================================================== */
:root{
  --ink:      #030710;
  --ink-2:    #060c18;
  --ice:      #8fe3ff;
  --ice-hi:   #eaf8ff;
  --deep:     #1b3a6b;
  --text-dim: #7fa8c4;
  --font-ui:  -apple-system, BlinkMacSystemFont, "SF Pro Display", "Helvetica Neue", Arial, sans-serif;
}

*{ margin:0; padding:0; box-sizing:border-box; }
html,body{
  background:var(--ink); color:var(--ice-hi); font-family:var(--font-ui);
  height:100%; overflow:hidden; /* 页面绝不滚动 */
  touch-action:none;
}

/* ---------------- loader ---------------- */
#loader1{
  position:fixed; inset:0; z-index:200; background:var(--ink);
  display:flex; flex-direction:column; align-items:center; justify-content:center; gap:18px;
  transition:opacity .8s cubic-bezier(.4,0,.2,1), visibility .8s;
}
#loader1.hide{ opacity:0; visibility:hidden; }
.loader-lottie1{
  display:block; width:66px; height:66px; margin-bottom:-4px;
  filter:drop-shadow(0 0 12px rgba(143,227,255,.6));
}
.loader-lottie1 svg{ width:100%; height:100%; }
.l1-mark{
  font-size:15px; letter-spacing:6px; font-weight:600; color:var(--ice-hi);
  text-shadow:0 0 20px rgba(143,227,255,.6);
}
.l1-bar{ width:220px; height:1px; background:rgba(143,227,255,.15); position:relative; }
.l1-bar-fill{
  position:absolute; inset:0 auto 0 0; width:0%; background:var(--ice);
  box-shadow:0 0 10px var(--ice); transition:width .2s ease-out;
}
.l1-pct{ font-size:11px; letter-spacing:1px; color:var(--ice); font-variant-numeric:tabular-nums; }

/* ---------------- stage ---------------- */
#stage1{ position:fixed; inset:0; overflow:hidden; }
#gl1{ position:absolute; inset:0; width:100%; height:100%; display:block; filter:saturate(1.08) brightness(1.02); }

/* vignette (single soft gradient, no repeating pattern) */
#stage1::after{
  content:""; position:absolute; inset:0; pointer-events:none; z-index:2;
  background:radial-gradient(ellipse at 50% 45%, rgba(3,7,16,0) 40%, rgba(3,7,16,.82) 100%);
}

/* ---------------- top chrome ---------------- */
.chrome1-top{
  position:absolute; top:0; left:0; right:0; z-index:20;
  display:flex; justify-content:space-between; align-items:center;
  padding:28px clamp(24px,5vw,64px);
}
.brand1{ font-size:13px; letter-spacing:3px; font-weight:600; display:flex; align-items:center; gap:9px; }
.brand1 span{ color:var(--ice); }
.bat-lottie1{
  display:inline-block; width:33px; height:33px; flex-shrink:0;
  filter:drop-shadow(0 0 6px rgba(143,227,255,.55));
}
.bat-lottie1 svg{ width:100%; height:100%; }
.tag1{
  font-size:10.5px; letter-spacing:2.5px; color:var(--text-dim);
  padding:7px 14px; border:1px solid rgba(143,227,255,.22); border-radius:100px;
  backdrop-filter:blur(10px); background:rgba(143,227,255,.04);
  /* 语言切换按钮：视觉与原来的纯展示徽标完全一致，只是补齐按钮的基础重置 */
  font-family:inherit; appearance:none; -webkit-appearance:none; cursor:pointer;
  display:inline-flex; align-items:center; gap:7px; line-height:1;
  transition:border-color .25s, color .25s, background .25s;
}
.tag1:hover, .tag1[aria-expanded="true"]{
  border-color:rgba(143,227,255,.5); color:var(--ice-hi); background:rgba(143,227,255,.08);
}
.lang1-chevron{ flex-shrink:0; transition:transform .25s ease; }
.tag1[aria-expanded="true"] .lang1-chevron{ transform:rotate(180deg); }

.lang1-wrap{ position:relative; }
.lang1-menu{
  position:absolute; top:calc(100% + 10px); right:0; z-index:30;
  list-style:none; margin:0; padding:6px; min-width:148px;
  background:rgba(6,14,26,.94); backdrop-filter:blur(18px);
  border:1px solid rgba(143,227,255,.18); border-radius:14px;
  box-shadow:0 24px 60px rgba(0,0,0,.55);
  opacity:0; transform:translateY(-6px); pointer-events:none;
  transition:opacity .22s ease, transform .22s ease;
}
.lang1-menu.open{ opacity:1; transform:translateY(0); pointer-events:auto; }
.lang1-menu[hidden]{ display:block; } /* 用 opacity 控显隐，配合过渡动画；hidden 属性只作初始态占位 */
.lang1-menu li{
  font-size:12.5px; letter-spacing:.3px; color:var(--text-dim);
  padding:9px 12px; border-radius:9px; cursor:pointer; white-space:nowrap;
  transition:background .18s, color .18s;
}
.lang1-menu li:hover{ background:rgba(143,227,255,.09); color:var(--ice-hi); }
.lang1-menu li[aria-selected="true"]{ color:var(--ice); font-weight:600; }

.scene-index1{
  position:absolute; top:30px; right:50%; z-index:20; transform:translateX(50%);
  font-size:12px; letter-spacing:2px; color:var(--text-dim); font-variant-numeric:tabular-nums;
  display:none; /* 移动端可开启，桌面暂不需要 */
}
.slash{ opacity:.4; margin:0 2px; }

/* ---------------- chapters (text choreography) ---------------- */
.chapters1{ position:absolute; inset:0; z-index:15; pointer-events:none; }
.chapter1{
  position:absolute; left:clamp(24px,7vw,110px); top:50%;
  --chapter-anchor:-50%; /* JS 的位移动画会读它：决定文字块以哪里为锚点 */
  transform:translateY(var(--chapter-anchor));
  max-width:620px; /* 放宽一点：保证各语言标题都能稳定排成两行 */
  will-change:transform,opacity;
  pointer-events:auto;
}
.eyebrow1{
  font-size:11px; letter-spacing:3px; color:var(--ice); margin-bottom:18px; font-weight:600;
}
.chapter1 h1{
  font-size:clamp(32px, 5.4vw, 58px); line-height:1.08; font-weight:700; letter-spacing:-0.5px;
  color:var(--ice-hi);
  text-shadow:0 0 30px rgba(143,227,255,.28);
}
.chapter1 p{
  margin-top:22px; font-size:15px; line-height:1.85; color:var(--text-dim); max-width:460px;
}
.chapter1 p + p{ margin-top:14px; }
.facts1{
  display:flex; flex-wrap:wrap; gap:8px 18px; margin-top:22px;
  min-height:20px; color:rgba(234,248,255,.9);
}
.fact1{
  position:relative; padding-left:14px; font-size:12px; line-height:1.5;
  letter-spacing:1.35px; font-weight:600; text-transform:uppercase; white-space:nowrap;
}
.fact1::before{
  content:""; position:absolute; left:0; top:50%; width:4px; height:4px;
  border-radius:50%; background:var(--ice); transform:translateY(-50%);
  box-shadow:0 0 9px rgba(143,227,255,.9);
}
/* 02 的后两段是次级说明：字号略小于正文，但保持可读 */
.chapter1[data-i="2"] p[data-body2],
.chapter1[data-i="2"] p[data-body3]{
  font-size:13px; line-height:1.8;
}

.cta1-row{ display:flex; flex-wrap:wrap; gap:14px; margin-top:30px; }
.cta1{
  display:inline-flex; align-items:center; justify-content:center; gap:9px;
  font-family:var(--font-ui); font-size:13px; letter-spacing:2px; font-weight:600;
  color:var(--ink); background:var(--ice-hi); padding:15px 26px; border-radius:100px;
  text-decoration:none; cursor:pointer;
  box-shadow:0 0 30px rgba(143,227,255,.4);
  transition:transform .25s, box-shadow .25s;
}
.cta1 svg{ flex-shrink:0; display:block; }
.cta1:hover{ transform:translateY(-2px); box-shadow:0 0 46px rgba(143,227,255,.65); }
.legal1-links{
  display:flex; align-items:center; gap:10px; margin-top:18px;
  font-size:12px; letter-spacing:1.1px; color:rgba(127,168,196,.72);
}
.legal1-links a{
  color:var(--text-dim); text-decoration:none;
  transition:color .2s ease, text-shadow .2s ease;
}
.legal1-links a:hover{
  color:var(--ice-hi); text-shadow:0 0 14px rgba(143,227,255,.42);
}

/* ---------------- hint：可继续下滑时显示的大号动态箭头 ---------------- */
.hint1{
  position:absolute; bottom:34px; left:50%; transform:translateX(-50%); z-index:20;
  display:flex; flex-direction:column; align-items:center; gap:1px; color:var(--ice);
  transition:opacity .4s ease, visibility .4s ease;
}
.hint1.is-hidden{ opacity:0; visibility:hidden; }
.hint1-chevron{
  width:30px; height:16px;
  filter:drop-shadow(0 0 10px rgba(143,227,255,.65));
}
.hint1-chevron.c1{ animation:hint1-chev 1.7s ease-in-out infinite; }
.hint1-chevron.c2{ animation:hint1-chev 1.7s ease-in-out infinite; animation-delay:.28s; opacity:.5; }
@keyframes hint1-chev{
  0%{ opacity:.2; transform:translateY(-6px); }
  55%{ opacity:1; transform:translateY(3px); }
  100%{ opacity:.2; transform:translateY(-6px); }
}

/* ---------------- mobile / touch ---------------- */
@media (hover:none), (pointer:coarse){
  .cta1, .brand1, .tag1{ -webkit-tap-highlight-color:transparent; }
  #gl1{ -webkit-touch-callout:none; }
}

@media (max-width:760px){
  .chrome1-top{
    padding:16px 18px;
    padding-top:calc(16px + env(safe-area-inset-top));
  }
  .brand1{ font-size:12px; letter-spacing:2.5px; }
  /* 语言切换徽标移动端同样保留（原来这里是纯展示的 ENCRYPTION CORE，现在是功能入口，样式不变） */
  .lang1-menu{ right:0; }

  /* 每屏文字位置错开：00/02 锚在顶部、01/03 锚在底部、04 贴底（配下载按钮）。
     粒子主体在屏幕中央，这样各屏都尽量不挡住它，也不显得每屏千篇一律 */
  .chapter1{ left:22px; right:22px; max-width:none; --chapter-anchor:0px; }
  .chapter1[data-i="0"]{ top:calc(env(safe-area-inset-top) + 98px); bottom:auto; } /* 顶栏高约48px+20px间距，再整体下移30px */
  .chapter1[data-i="2"]{ top:calc(env(safe-area-inset-top) + 92px); bottom:auto; }
  .chapter1[data-i="1"], .chapter1[data-i="3"]{ top:auto; bottom:calc(96px + env(safe-area-inset-bottom)); }
  .chapter1[data-i="4"]{ top:auto; bottom:calc(44px + env(safe-area-inset-bottom)); }
  .eyebrow1{ font-size:10px; margin-bottom:12px; }
  .chapter1 h1{ font-size:clamp(26px, 8.6vw, 38px); line-height:1.12; }
  .chapter1 p{ margin-top:16px; font-size:13.5px; line-height:1.75; max-width:none; }
  .facts1{ margin-top:14px; gap:7px 14px; }
  .fact1{ font-size:11px; letter-spacing:1px; }
  .chapter1[data-i="2"] p[data-body2],
  .chapter1[data-i="2"] p[data-body3]{
    font-size:12px; line-height:1.72;
  }

  .cta1-row{ flex-direction:column; gap:12px; margin-top:26px; }
  .cta1{
    width:100%; padding:16px 24px; font-size:13px;
  }
  .chapter1[data-i="4"] .cta1-row{ align-items:flex-start; }
  .chapter1[data-i="4"] .cta1{ width:min(270px, 100%); }
  .legal1-links{ margin-top:16px; font-size:11px; letter-spacing:.8px; }

  .hint1{
    bottom:calc(28px + env(safe-area-inset-bottom));
  }
  .hint1-chevron{ width:26px; height:14px; }
}

@media (max-width:400px){
  .chapter1 h1{ font-size:7.2vw; }
}

/* 横屏手机：文字区收窄高度占比，避免与顶部/底部 UI 拥挤 */
@media (max-width:900px) and (max-height:480px) and (orientation:landscape){
  /* 横屏空间矮，恢复统一垂直居中，覆盖竖屏的每屏锚点 */
  .chapter1[data-i]{ top:50%; bottom:auto; --chapter-anchor:-50%; }
  .chapter1 p{ display:none; }
  .hint1{ display:none; }
}