/* ==========================================================================
   BP Talk — website stylesheet
   Generated site: E:\PTT\site2  ·  single source for every page
   Brand accent is the product green (#07C160), matching the app icon.
   ========================================================================== */

:root{
  --brand:#07C160; --brand-d:#059c4d; --brand-l:#e7f9ef; --brand-glow:rgba(7,193,96,.30);
  --ink:#0b1622; --ink2:#1d2f42; --muted:#5b6b7f; --line:#e3e9f0;
  --bg:#ffffff; --soft:#f5f8fb; --dark:#07131f; --dark2:#0c2033;
  --max:1180px; --radius:22px; --shadow:0 24px 70px rgba(8,28,56,.12);
  --shadow-sm:0 8px 26px rgba(8,28,56,.08);
}

*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Noto Sans","Noto Sans SC","Noto Sans TC",sans-serif;color:var(--ink);background:var(--bg);line-height:1.65;font-size:16px}
a{color:inherit;text-decoration:none}
img,svg{max-width:100%}
.container{width:min(var(--max),calc(100% - 40px));margin:auto}
.visually-hidden{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
/* 无障碍跳转链接。隐藏方式必须用「垂直位移」，不能用 left:-9999px。
   原因：绝对定位元素向左溢出会扩大文档的可滚动区域 —— RTL 文档算溢出，LTR 文档
   浏览器会忽略左溢出。于是 dir="rtl" 的页面被撑出约 10000px 横向空白，整个内容
   被推出视口：无头截图整页纯白，真实用户侧则是顶部内容错位 + 巨大横向滚动条。
   垂直方向的负溢出在任何书写方向下都不产生滚动区域，方向无关。# [_fix_skip_rtl] */
.skip{position:absolute;top:0;left:0;z-index:100;transform:translateY(-160%);background:var(--brand);color:#fff;padding:12px 18px;border-end-start-radius:12px;transition:transform .15s ease}
.skip:focus{transform:translateY(0)}

/* ------------------------------------------------------------------ header */
.nav{position:sticky;top:0;z-index:60;background:rgba(7,19,31,.92);backdrop-filter:blur(12px);color:#fff;border-bottom:1px solid rgba(255,255,255,.07)}
.nav-inner{min-height:70px;display:flex;align-items:center;justify-content:space-between;gap:18px}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:18px;letter-spacing:-.01em;white-space:nowrap}
.logo{width:30px;height:30px;flex:0 0 auto}
.navlinks{display:flex;gap:24px;align-items:center;font-size:13.5px;font-weight:600}
.navlinks a{opacity:.85;padding:4px 0;border-bottom:2px solid transparent}
.navlinks a:hover{opacity:1}
.navlinks a[aria-current="page"]{opacity:1;border-bottom-color:var(--brand)}
/* 语言选择器：<details> 原生下拉，无 JavaScript 依赖，键盘可用，
   每个语言是真实链接（爬虫可跟随） */
.langwrap{position:relative;display:flex;align-items:center}
.langpick{position:relative}
.langpick>summary{list-style:none;display:inline-flex;align-items:center;gap:7px;background:rgba(255,255,255,.06);color:#fff;border:1px solid rgba(255,255,255,.22);padding:8px 13px;border-radius:999px;font-size:13px;font-weight:700;cursor:pointer;user-select:none;white-space:nowrap}
.langpick>summary::-webkit-details-marker{display:none}
.langpick>summary::marker{content:""}
.langcur{letter-spacing:.05em}
.langpick>summary:after{content:"";width:0;height:0;border-left:5px solid transparent;border-right:5px solid transparent;border-top:5.5px solid #cfe0f0;transition:transform .18s ease}
.langpick[open]>summary:after{transform:rotate(180deg)}
.langpick>summary:hover{background:rgba(255,255,255,.12)}
.langpick[open]>summary{background:rgba(255,255,255,.14);border-color:rgba(255,255,255,.4)}
.langmenu{position:absolute;right:0;top:calc(100% + 9px);z-index:80;min-width:208px;max-height:min(62vh,430px);overflow:auto;overscroll-behavior:contain;background:#0b1a28;border:1px solid rgba(255,255,255,.16);border-radius:14px;box-shadow:0 18px 44px rgba(0,0,0,.5);padding:6px}
.langmenu a{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:9px 12px;border-radius:9px;font-size:14px;font-weight:600;color:#d7e4f0}
.langmenu a span{font-size:10.5px;font-weight:800;letter-spacing:.07em;color:#7b93a9}
.langmenu a:hover{background:rgba(255,255,255,.09);color:#fff}
.langmenu a[aria-current="true"]{background:rgba(7,193,96,.14);color:#4fd48c}
.langmenu a[aria-current="true"] span{color:#4fd48c}

/* mobile navigation -------------------------------------------------------- */
.navtoggle{display:none;align-items:center;justify-content:center;width:42px;height:42px;border-radius:12px;background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.18);cursor:pointer;padding:0}
.navtoggle span{display:block;width:18px;height:2px;background:#fff;position:relative;border-radius:2px}
.navtoggle span:before,.navtoggle span:after{content:"";position:absolute;left:0;width:18px;height:2px;background:#fff;border-radius:2px;transition:transform .2s ease,top .2s ease}
.navtoggle span:before{top:-6px}.navtoggle span:after{top:6px}
.navopen .navtoggle span{background:transparent}
.navopen .navtoggle span:before{top:0;transform:rotate(45deg)}
.navopen .navtoggle span:after{top:0;transform:rotate(-45deg)}

.mobilenav{display:none;border-top:1px solid rgba(255,255,255,.1);background:rgba(7,19,31,.98);padding:10px 0 22px}
.navopen .mobilenav{display:block}
.mobilenav a{display:block;padding:13px 0;font-size:15px;font-weight:600;border-bottom:1px solid rgba(255,255,255,.07)}
.mobilenav a[aria-current="page"]{color:#4fd48c}
.mobilenav .langwrap{margin-top:16px;display:block}
.mobilenav .langpick{display:block;width:100%}
.mobilenav .langpick>summary{display:flex;width:100%;justify-content:space-between;font-size:13.5px;padding:9px 13px}
.mobilenav .langmenu{position:static;margin-top:8px;max-height:none;box-shadow:none;background:rgba(255,255,255,.05);border-color:rgba(255,255,255,.12)}
.mobilenav .langmenu a{padding:11px 12px;border-bottom:0;border-radius:9px;font-size:14.5px}

/* 移动端：不再整块隐藏 .navlinks，只隐藏导航链接，
   把语言选择器常驻在顶栏（原来藏在汉堡菜单底部，用户找不到）*/
@media(max-width:960px){
  .navlinks{display:flex;gap:0;margin-left:auto}
  .navlinks>a{display:none}
  .navtoggle{display:inline-flex;margin-left:10px}
  .navlinks .langpick>summary{padding:7px 12px;font-size:12px}
}
@media(max-width:430px){
  .brand span{display:none}
  .navlinks .langpick>summary{padding:6px 10px;font-size:11.5px}
}

/* -------------------------------------------------------------------- hero */
.hero{background:radial-gradient(circle at 76% 18%,var(--brand-glow),transparent 34%),linear-gradient(120deg,#06101d,#0a1f31 55%,#07131f);color:#fff;position:relative;overflow:hidden;padding:78px 0 96px}
.hero-inner{display:grid;grid-template-columns:1.05fr .95fr;align-items:center;gap:44px}
.eyebrow,.kicker{letter-spacing:.18em;text-transform:uppercase;font-size:12px;font-weight:800;color:var(--brand)}
.hero .eyebrow{color:#5fe0a0}
.hero h1{font-size:clamp(40px,5.4vw,68px);line-height:1.04;letter-spacing:-.04em;margin:16px 0 18px;font-weight:800}
.hero h1 span{color:#4fd48c}
.hero p{font-size:18px;max-width:600px;color:#c3d3e4;margin:0}
.buttons{display:flex;gap:12px;flex-wrap:wrap;margin:28px 0 18px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:9px;padding:14px 22px;border-radius:14px;font-weight:800;font-size:14.5px;border:1px solid transparent;cursor:pointer;transition:transform .12s ease,box-shadow .12s ease}
.btn:active{transform:translateY(1px)}
.btn-primary{background:var(--brand);color:#fff;box-shadow:0 12px 30px var(--brand-glow)}
.btn-primary:hover{background:var(--brand-d)}
.btn-ghost{border-color:rgba(255,255,255,.4);color:#fff}
/* Secondary CTA in the hero: a plain text link, deliberately much lighter
   than the primary button so the first screen offers one obvious choice. */
.btn-link{background:none;border:0;color:inherit;opacity:.82;font-weight:700;padding:14px 6px;text-decoration:none}
.btn-link:hover{opacity:1;text-decoration:underline}
.btn-link:after{content:"\2193";margin-left:3px;font-size:15px;line-height:1}
/* Row for the demoted secondary CTA. It sits under the meta line so
   the hero presents exactly one dominant action. */
.hero-linkrow{display:flex;flex-wrap:wrap;gap:12px;margin:16px 0 0}
.hero-linkrow .btn-link{padding-left:0;padding-right:0}
.btn-outline{border-color:var(--line);color:var(--ink);background:#fff}
.btn-outline:hover{border-color:var(--brand);color:var(--brand-d)}
.meta{font-size:13.5px;color:#93a7bf;display:flex;flex-wrap:wrap;gap:6px 14px}
.hero .meta{color:#93a7bf}
.meta span{display:inline-flex;align-items:center;gap:6px}
.meta span+span:before{content:"";width:4px;height:4px;border-radius:50%;background:currentColor;opacity:.5;margin-right:8px}

/* phone mock --------------------------------------------------------------- */
.phone-stage{position:relative;min-height:520px;display:flex;align-items:center;justify-content:center}
.phone{width:250px;height:512px;background:#07131f;border:8px solid #1d2b3d;border-radius:40px;box-shadow:0 40px 90px rgba(0,0,0,.45);padding:13px;position:relative;z-index:2}
.phone.back{position:absolute;transform:translate(150px,32px) rotate(7deg);opacity:.9;z-index:1}
.phone.back .screen{filter:saturate(.7)}
.screen{height:100%;border-radius:28px;background:linear-gradient(180deg,#102038,#07131f);padding:18px;color:#fff;display:flex;flex-direction:column}
.screen-top{font-size:11px;color:#91a5be;display:flex;justify-content:space-between}
.channel{margin-top:18px;padding:13px;border-radius:15px;background:#132641}
.channel small{color:#90a5be;font-size:11px;display:block}
.channel strong{display:block;font-size:15px}
.ptt{width:138px;height:138px;border-radius:50%;margin:44px auto 16px;background:radial-gradient(circle at 35% 30%,#4fd48c,var(--brand) 60%,#059c4d);display:flex;align-items:center;justify-content:center;color:#fff;font-size:30px;cursor:pointer;user-select:none;animation:pttPulse 2.4s ease-in-out infinite;transition:transform .12s ease,filter .12s ease}
.ptt:active,.ptt.talking{transform:scale(.96);filter:brightness(1.12)}
.hold{text-align:center;font-size:13px;color:#b8c8da}
.hold.talking{color:#4fd48c;font-weight:800}
.phonemeta{margin-top:auto;display:flex;justify-content:space-between;color:#7f93ad;font-size:10px}
@keyframes pttPulse{0%,100%{box-shadow:0 0 0 12px rgba(7,193,96,.08),0 0 35px rgba(7,193,96,.30)}50%{box-shadow:0 0 0 20px rgba(7,193,96,.04),0 0 62px rgba(7,193,96,.55)}}
.wave{position:absolute;left:-4%;right:-4%;bottom:24px;height:90px;width:108%;opacity:.55}
.wave path{stroke:var(--brand);stroke-dasharray:12 10;animation:waveMove 3s linear infinite}
@keyframes waveMove{to{stroke-dashoffset:-220}}

/* --------------------------------------------------------------------- page */
.section{padding:88px 0}
.section.soft{background:var(--soft)}
.section.dark{background:linear-gradient(120deg,#06101d,#0a1f31);color:#fff}
.section h2{font-size:clamp(28px,3.4vw,40px);line-height:1.14;letter-spacing:-.03em;margin:10px 0 14px;font-weight:800}
.section.dark h2{color:#fff}
.lead{font-size:17px;color:var(--muted);max-width:760px;margin:0}
.section.dark .lead{color:#b8c8da}
h3{font-size:19px;margin:0 0 8px;font-weight:800;letter-spacing:-.01em}
p{margin:0 0 12px}
p:last-child{margin-bottom:0}

/* page head (inner pages) -------------------------------------------------- */
.pagehead{background:radial-gradient(circle at 78% 12%,var(--brand-glow),transparent 36%),linear-gradient(120deg,#06101d,#0a1f31 60%,#07131f);color:#fff;padding:74px 0 62px}
.pagehead h1{font-size:clamp(32px,4.2vw,52px);line-height:1.1;letter-spacing:-.035em;margin:14px 0 14px;font-weight:800}
.pagehead .lead{color:#c3d3e4}
.crumbs{font-size:13px;color:#8ea3bb;margin-bottom:14px}
.crumbs a:hover{color:#fff}
.crumbs span{opacity:.55;margin:0 8px}

/* ------------------------------------------------------------------ layout */
.grid2{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center}
.grid2.top{align-items:start}
.compare{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-top:36px}
.card{border:1px solid var(--line);border-radius:var(--radius);padding:26px;background:#fff;box-shadow:var(--shadow-sm)}
.card.highlight{border-color:var(--brand);background:var(--brand-l);box-shadow:0 20px 50px rgba(7,193,96,.16)}
.steps{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}
.step{display:inline-flex;align-items:center;gap:8px;font-size:13.5px;color:var(--ink2);background:var(--soft);border-radius:999px;padding:7px 13px}
.card.highlight .step{background:#fff}
.num{width:20px;height:20px;border-radius:50%;background:var(--ink);color:#fff;display:inline-flex;align-items:center;justify-content:center;font-size:11px;font-weight:800}
.card.highlight .num{background:var(--brand)}

.features{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin-top:34px}
.feature{display:flex;gap:15px;align-items:flex-start;background:#fff;border:1px solid var(--line);border-radius:18px;padding:20px}
.feature .icon{flex:0 0 auto;width:34px;height:34px;border-radius:11px;background:var(--brand-l);color:var(--brand-d);display:flex;align-items:center;justify-content:center;font-weight:800;font-size:14px}
.feature strong{display:block;font-size:16.5px;margin-bottom:4px}
.feature p{font-size:14.5px;color:var(--muted);margin:0}

/* 首页功能分级：4 个一级卖点大卡 + 4 项紧凑行（审计 ⑨，仅首页） --------------
   .features.topgrid 走 2 列（容器 1180px，每张约 570px）；一排 4 张只剩 277px，
   "Self-healing connection" 这类标题会被挤成两三行，故用 2×2。
   卡片改为纵向（图标在上）；.features.more 走 2 列紧凑行，与上半区同节奏。
   类名不带数量：加减卖点只改 FEATURE_TOP 与本文件列数，不必再改类名。
   RTL 下 .feature 的基础规则是 row-reverse，纵向卡片必须显式改回 column，
   否则图标与文字会并排（选择器权重：html[dir] + .feature 高于 .feature.top）。 */
.features.topgrid{grid-template-columns:repeat(2,1fr);gap:20px;margin-top:36px}
.feature.top{flex-direction:column;gap:16px;padding:28px 26px;border-radius:20px;
  background:linear-gradient(180deg,#fff 0%,#f4fdf8 100%);
  border-color:rgba(7,193,96,.30);box-shadow:0 18px 44px rgba(7,193,96,.10)}
.feature.top .ficon{width:46px;height:46px;border-radius:14px;background:var(--brand);
  color:#fff;display:flex;align-items:center;justify-content:center;
  box-shadow:0 10px 22px rgba(7,193,96,.30)}
.feature.top .ficon svg{width:24px;height:24px}
.feature.top strong{font-size:18.5px;letter-spacing:-.015em;margin-bottom:6px}
.feature.top p{font-size:15px}
.features.more{grid-template-columns:1fr 1fr;gap:14px;margin-top:16px}
.feature.mini{padding:16px 18px;border-radius:15px;gap:13px}
.feature.mini .tick{flex:0 0 auto;width:9px;height:9px;border-radius:50%;
  background:var(--brand);margin-top:8px}
.feature.mini strong{font-size:15px;margin-bottom:2px}
.feature.mini p{font-size:13.5px}
html[dir="rtl"] .feature.top{flex-direction:column;text-align:right}

.usecases{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:34px}
.use{background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px}
.use .dot{width:10px;height:10px;border-radius:50%;background:var(--brand);margin-bottom:12px}
.use h3{font-size:16.5px}
.use h3 a{color:inherit;text-decoration:none;border-bottom:1px solid transparent;transition:color .12s ease,border-color .12s ease}
.use h3 a:hover{color:var(--brand);border-bottom-color:var(--brand)}
.use p{font-size:14.5px;color:var(--muted);margin:0}

.checks{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-top:26px}
.check{display:flex;gap:11px;align-items:flex-start;background:rgba(255,255,255,.05);border:1px solid rgba(255,255,255,.12);border-radius:14px;padding:15px 17px;font-size:14.5px}
.check b{color:var(--brand);font-weight:800}

.steps-list{counter-reset:s;margin-top:34px;display:grid;gap:16px}
.stepline{display:flex;gap:18px;background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px}
.stepline .n{flex:0 0 auto;width:36px;height:36px;border-radius:12px;background:var(--brand);color:#fff;display:flex;align-items:center;justify-content:center;font-weight:800}
.stepline p{color:var(--muted);font-size:15px;margin:6px 0 0}

/* prose -------------------------------------------------------------------- */
.prose{max-width:860px}
.prose .sec{margin-top:30px}
.prose .sec h3{font-size:18px}
.prose .sec p{color:var(--muted);font-size:15.5px}
.prose ul{margin:8px 0 0;padding-left:20px;color:var(--muted);font-size:15.5px}
.prose li{margin-bottom:7px}

/* table -------------------------------------------------------------------- */
.tablewrap{margin-top:28px;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;background:#fff}
table{width:100%;border-collapse:collapse}
th,td{text-align:left;padding:16px 20px;font-size:15px;vertical-align:top;border-bottom:1px solid var(--line)}
tbody tr:last-child th,tbody tr:last-child td{border-bottom:0}
th{width:220px;font-weight:800;color:var(--ink);background:var(--soft)}
td{color:var(--muted)}
.section.dark th{background:rgba(255,255,255,.05);color:#fff;border-color:rgba(255,255,255,.12)}
.section.dark td{color:#b8c8da;border-color:rgba(255,255,255,.12)}
.section.dark .tablewrap{border-color:rgba(255,255,255,.14);background:rgba(255,255,255,.03)}

/* download / release ------------------------------------------------------- */
.dlbox{background:linear-gradient(120deg,#06101d,#0a1f31 60%,#07131f);color:#fff;border-radius:28px;padding:46px;display:grid;grid-template-columns:1.1fr .9fr;gap:34px;align-items:center;box-shadow:var(--shadow)}
.dlbox h2{color:#fff;margin-top:6px}
.dlbox .lead{color:#c3d3e4}
.dlmeta{display:grid;gap:9px;font-size:14.5px}
.dlmeta .row{display:flex;justify-content:space-between;gap:18px;border-bottom:1px dashed rgba(255,255,255,.16);padding-bottom:9px}
.dlmeta .row span:first-child{color:#9ab0c8}
.dlmeta .row span:last-child{font-weight:700;text-align:right;word-break:break-all}
.dlmeta .big{font-size:30px;font-weight:800;color:#4fd48c;letter-spacing:-.03em}

.release{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:34px}
.relcard{background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px;box-shadow:var(--shadow-sm)}
.relcard .k{font-size:12px;letter-spacing:.14em;text-transform:uppercase;color:var(--muted);font-weight:800}
.relcard .v{font-size:22px;font-weight:800;margin-top:6px;letter-spacing:-.02em}
.relcard .v.mono{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:15px;word-break:break-all}

/* verify / hash panel ------------------------------------------------------ */
.verify{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:34px;box-shadow:var(--shadow-sm);margin-top:34px}
.verify-grid{display:grid;grid-template-columns:1.35fr .65fr;gap:34px;align-items:start}
.hashrow{display:flex;gap:10px;align-items:stretch;margin-top:10px}
.hashrow code{flex:1;background:var(--soft);border:1px solid var(--line);border-radius:12px;padding:12px 14px;font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;font-size:13px;word-break:break-all;line-height:1.5}
.copybtn{flex:0 0 auto;border:1px solid var(--line);background:#fff;border-radius:12px;padding:0 16px;font-weight:800;font-size:13px;cursor:pointer;color:var(--ink)}
.copybtn:hover{border-color:var(--brand);color:var(--brand-d)}
.copybtn.done{border-color:var(--brand);background:var(--brand-l);color:var(--brand-d)}
.hashlabel{font-size:12.5px;letter-spacing:.14em;text-transform:uppercase;font-weight:800;color:var(--muted);margin-top:20px}
.hashlabel:first-child{margin-top:0}
.qrbox{text-align:center;background:var(--soft);border:1px solid var(--line);border-radius:18px;padding:22px}
.qrbox svg{width:180px;height:180px;background:#fff;border-radius:12px;padding:10px;box-shadow:var(--shadow-sm)}
.qrbox p{font-size:13.5px;color:var(--muted);margin:14px 0 0}
/* 下载面板（.verify 容器复用）：左列是动作，右列是二维码。
   .dlgo 在右侧二维码框旁垂直居中；RTL 下 flex-start 自动靠右，无需另写规则。 */
.dlgo{display:flex;flex-direction:column;align-items:flex-start;gap:14px;align-self:center}
/* 下载页主按钮加大：这是全站唯一真正的转化动作，移动端拇指命中区要够大。
   仅作用于 .dlgo 内的 btn-primary，首页 hero 的按钮尺寸不受影响。 */
.dlgo .btn-primary{padding:19px 36px;font-size:17px;border-radius:14px;
  box-shadow:0 8px 22px rgba(37,99,235,.26)}
.dlgo .btn-primary:active{transform:translateY(1px)}
.dlnote{margin:0}
.dlnote a{font-size:13.5px;color:var(--muted);text-decoration:underline;text-underline-offset:3px}
.dlnote a:hover{color:var(--brand-d)}

/* changelog ---------------------------------------------------------------- */
.timeline{margin-top:36px;position:relative;padding-left:30px}
.timeline:before{content:"";position:absolute;left:7px;top:8px;bottom:8px;width:2px;background:var(--line)}
.rel{position:relative;padding-bottom:34px}
.rel:before{content:"";position:absolute;left:-30px;top:7px;width:16px;height:16px;border-radius:50%;background:#fff;border:3px solid var(--line);box-sizing:border-box}
.rel.current:before{border-color:var(--brand);box-shadow:0 0 0 5px var(--brand-l)}
.relhead{display:flex;flex-wrap:wrap;gap:10px;align-items:center}
.relhead .ver{font-size:19px;font-weight:800;letter-spacing:-.02em}
.relhead .bld{font-size:12.5px;font-weight:800;color:var(--muted);background:var(--soft);border-radius:999px;padding:4px 11px}
.relhead .date{font-size:13px;color:var(--muted);margin-left:auto}
.badge-now{font-size:11.5px;font-weight:800;letter-spacing:.1em;text-transform:uppercase;color:var(--brand-d);background:var(--brand-l);border-radius:999px;padding:5px 11px}
.rel ul{margin:12px 0 0;padding-left:20px;color:var(--muted);font-size:15px}
.rel li{margin-bottom:8px}

/* faq ---------------------------------------------------------------------- */
.faq{margin-top:32px;display:grid;gap:12px;max-width:900px}
.faq details{background:#fff;border:1px solid var(--line);border-radius:16px;padding:4px 22px}
.faq summary{cursor:pointer;padding:18px 0;font-weight:700;font-size:16.5px;list-style:none;display:flex;justify-content:space-between;gap:16px;align-items:center}
.faq summary::-webkit-details-marker{display:none}
.faq summary:after{content:"+";font-size:20px;color:var(--brand);font-weight:700;flex:0 0 auto}
.faq details[open] summary:after{content:"–"}
.faq details p{color:var(--muted);font-size:15.5px;padding-bottom:20px;margin:0}

/* contact cards ------------------------------------------------------------ */
.contactcards{display:grid;grid-template-columns:1fr 1fr;gap:22px;margin-top:34px}
.ccard{background:#fff;border:1px solid var(--line);border-radius:20px;padding:26px;box-shadow:var(--shadow-sm)}
.ccard h3{font-size:17px}
.ccard p{color:var(--muted);font-size:15px;margin:8px 0 14px}
.ccard a.mail{display:inline-flex;align-items:center;gap:8px;font-weight:800;color:var(--brand-d);word-break:break-all}
.ccard a.mail:hover{text-decoration:underline}

/* language grid ------------------------------------------------------------ */
.langgrid{display:grid;grid-template-columns:repeat(auto-fill,minmax(178px,1fr));gap:12px;margin-top:30px}
.langgrid a{display:block;background:#fff;border:1px solid var(--line);border-radius:14px;padding:15px 18px;font-weight:700;font-size:15px;transition:border-color .15s ease,transform .15s ease}
.langgrid a:hover{border-color:var(--brand);transform:translateY(-2px)}
.langgrid a .code{display:block;font-size:12px;font-weight:600;color:var(--muted);margin-top:3px;letter-spacing:.06em}
.langgrid a[aria-current="true"]{border-color:var(--brand);background:var(--brand-l)}

/* cta ---------------------------------------------------------------------- */
.cta{background:linear-gradient(120deg,#06101d,#0a1f31 60%,#07131f);color:#fff;border-radius:28px;padding:46px;text-align:center;margin-top:20px}
.cta h2{color:#fff}
.cta .lead{color:#c3d3e4;margin:0 auto 24px}
.cta .buttons{justify-content:center;margin-bottom:0}

/* footer ------------------------------------------------------------------- */
.footer{background:#07131f;color:#9db0c9;padding:66px 0 30px;font-size:14.5px}
.footer-grid{display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr 1fr;gap:30px}
.footer .brand{color:#fff;margin-bottom:14px}
.footer h4{color:#fff;font-size:13px;letter-spacing:.14em;text-transform:uppercase;margin:0 0 14px;font-weight:800}
.footer a{display:block;padding:4px 0;opacity:.85}
.footer a:hover{opacity:1;color:#4fd48c}
.footer p{font-size:13.5px;max-width:280px}
.footer .op{margin-top:10px;font-size:13px;line-height:1.7}
.footer .op a{display:inline;padding:0}
.copyright{margin-top:44px;padding-top:22px;border-top:1px solid rgba(255,255,255,.1);display:flex;justify-content:space-between;gap:16px;font-size:13px;flex-wrap:wrap}
.totop{color:#9db0c9}
.totop:hover{color:#fff}

/* ------------------------------------------------------------------ rtl ---- */
html[dir="rtl"] body{text-align:right}
html[dir="rtl"] .navlinks,html[dir="rtl"] .buttons,html[dir="rtl"] .meta,html[dir="rtl"] .relhead,html[dir="rtl"] .hero-linkrow{flex-direction:row-reverse}
html[dir="rtl"] .crumbs span{transform:scaleX(-1);display:inline-block}
html[dir="rtl"] .prose ul,html[dir="rtl"] .rel ul{padding-left:0;padding-right:20px}
html[dir="rtl"] .feature{flex-direction:row-reverse;text-align:right}
html[dir="rtl"] .stepline{flex-direction:row-reverse;text-align:right}
html[dir="rtl"] .timeline{padding-left:0;padding-right:30px}
html[dir="rtl"] .timeline:before{left:auto;right:7px}
html[dir="rtl"] .rel:before{left:auto;right:-30px}
html[dir="rtl"] .relhead .date{margin-left:0;margin-right:auto}
html[dir="rtl"] th{text-align:right}
html[dir="rtl"] .langgrid{text-align:right}
html[dir="rtl"] .footer{text-align:right}
html[dir="rtl"] .langmenu{right:auto;left:0}

/* --------------------------------------------------------------- responsive */
@media(max-width:1080px){
  .footer-grid{grid-template-columns:1.4fr 1fr 1fr}
}
@media(max-width:960px){
  .hero-inner,.grid2,.dlbox,.verify-grid{grid-template-columns:1fr}
  .compare,.usecases,.features,.features.topgrid,.release{grid-template-columns:1fr 1fr}
  .phone-stage{min-height:520px;margin-top:10px}
  .phone.back{display:none}
  .section{padding:70px 0}
  .footer-grid{grid-template-columns:1fr 1fr}
  .contactcards,.checks{grid-template-columns:1fr}
  th{width:auto;display:block;border-bottom:0;padding-bottom:4px}
  td{display:block;padding-top:4px}
  tbody tr{display:block;border-bottom:1px solid var(--line);padding:14px 0}
  tbody tr:last-child{border-bottom:0}
  th,td{padding-left:20px;padding-right:20px}
}
@media(max-width:600px){
  .container{width:min(var(--max),calc(100% - 28px))}
  .compare,.usecases,.features,.features.topgrid,.features.more,.release,.footer-grid{grid-template-columns:1fr}
  .hero h1{font-size:38px}
  .hero{padding:48px 0 70px}
  .pagehead{padding:52px 0 46px}
  .dlbox,.cta,.verify{padding:28px 22px}
  /* 600px 以下基本就是手机在访问本页 —— 让用户扫自己屏幕上这个二维码
     没有意义，直接隐藏，只留下载按钮。（平板（600~960）保留二维码。） */
  .qrbox{display:none}
  .section{padding:58px 0}
  .phone{transform:scale(.9);transform-origin:top center}
  .copyright{display:block}
  .copyright span{display:block;margin-top:8px}
  .relhead .date{margin-left:0;width:100%}
}

/* real screenshots — used automatically once content/screenshots is filled in */
.phone-stage.shots{gap:22px}
.phone-stage.shots .shot{width:auto;max-height:520px;border-radius:26px;box-shadow:0 40px 90px rgba(0,0,0,.45)}
.phone-stage.shots .shot.back{position:absolute;transform:translate(46%,32px) rotate(6deg);opacity:.9;max-height:470px}
@media(max-width:960px){.phone-stage.shots .shot.back{display:none}}

@media(prefers-reduced-motion:reduce){
  *{animation:none!important;transition:none!important}
  html{scroll-behavior:auto}
}
@media print{
  .nav,.mobilenav,.footer,.cta{display:none}
}

/* ---- 演示视频区（demo 区块）---- */
/* 尺寸唯一来源：wrapper 固定写死 + video 100% 填充 + object-fit:contain。
   显示尺寸：桌面 420x933 / 移动 360x800（与源片 1080x2400 同比例 0.45）。
   🔴 不要给 wrapper 加 max-width/max-height 收缩约束，也不要用 aspect-ratio：
      曾因 max-* 与固有尺寸的交互在 Edge 上失效，导致视频按源片 1080 宽溢出。
      尺寸一律写死；窄屏用媒体查询按 100vw 递减。 */
.demo-grid{display:grid;grid-template-columns:1fr auto;gap:44px;align-items:center}
/* Anchor target of the hero secondary CTA (#demo). The nav is position:sticky
   (~64px tall), so scroll-margin keeps the video title from hiding under it. */
#demo{scroll-margin-top:84px}
.demo-copy{max-width:600px}
.demo{display:flex;justify-content:center;min-width:0}
.demo-wrap{
  display:block;flex:0 0 auto;
  width:420px;height:933px;
  background:#06121f;border:1px solid var(--line);
  border-radius:22px;box-shadow:0 16px 40px rgba(11,22,34,.22);
  overflow:hidden;
}
.demo-video{display:block;width:100%;height:100%;object-fit:contain}
.demo-cap{color:var(--muted);font-size:14px;margin:14px 0 0}
@media (max-width:900px){
  .demo-grid{grid-template-columns:1fr;gap:20px}
  .demo-copy{max-width:none;text-align:center}
  .demo-cap{text-align:center}
  .demo-wrap{width:360px;height:800px}
}
/* 极窄屏：容器可用宽 = 100vw - 40px（.container 左右各 20px），等比缩小。
   高度由宽度算出（420:933），不用 aspect-ratio。 */
@media (max-width:400px){
  .demo-wrap{width:calc(100vw - 40px);height:calc((100vw - 40px) * 933 / 420)}
}

/* ==========================================================================
   手机优先改版（2026-09-23）
   --------------------------------------------------------------------------
   两条线索：
     A. 首页手机端**区块重排** —— 纯 CSS order，零翻译、零 HTML 改动
     B. 底部固定下载栏（stickybar）
   设计原则：
     * 桌面端（>600px）**完全不受影响** —— 所有规则包在 max-width:600px 内
     * 用 :nth-of-type() 而非 :has() —— 后者需 Chrome 105+/Safari 15.4+，
       而本站访客浏览器未知；:nth-of-type 兼容性 100%
       （代价：位次与区块数量强绑定，故 build_site.py 的 check() 里加了
        断言把「首页区块数」锁死，任何人插区块会直接 FATAL 而不是静默错位）
     * 排序依据：首次访客决策路径
         1 这是什么        -> hero
         2 怎么用起来      -> demo（27 秒录屏）
         3 多快能开始      -> steps（30 秒开始，ref 自下载页，零翻译）
         4 和聊天 App 差别 -> comparison（三卡对比）
         5 谁在用          -> usecases
         6 有什么功能      -> featuregrid（下移：手机端次要）
         7 隐私承诺        -> checked
         8 在哪下载        -> downloadbox（提前到 FAQ 之前）
         9 还有疑问        -> faq
        10 其他语言        -> langs
   ========================================================================== */
@media (max-width:600px){
  /* ---- A. 首页区块重排 ---- */
  /* <main> 的直系子元素就是全部 <section>（render_page 不包 block 列表层），
     故这里可以直接对 <main> 用 flex+order 重排。 */
  #main{display:flex;flex-direction:column}
  #main>.hero{order:1}
  #main>#demo{order:2}
  /* 首页「30 秒开始」区块：.section 且内含 .steps-list（由 ref 复用下载页 steps 渲染）。
     用 nth-of-type 定序，见文件头说明。
     🔴 位次对照（首页 blocks 序，hero/demo 不占 .section 计数）：
          n-th 1 = blocks[2] steps        n-th 2 = blocks[3] comparison
          n-th 3 = blocks[4] featuregrid  n-th 4 = blocks[5] usecases
          n-th 5 = blocks[6] checked(.dark，用类选择器)
          n-th 6 = blocks[7] downloadbox  n-th 7 = blocks[8] faq
          n-th 8 = blocks[9] langs
     （2026-09-23 修正：原注释把 n-th 3/4 的注释写成 usecases/featuregrid，
       与实际 JSON 序相反。规则本身一直是对的，是注释在骗人。） */
  #main>.section:nth-of-type(1){order:3}   /* steps */
  #main>.section:nth-of-type(2){order:4}   /* comparison */
  #main>.section:nth-of-type(3){order:5}   /* featuregrid */
  #main>.section:nth-of-type(4){order:6}   /* usecases */
  #main>.section.dark{order:7}             /* checked（隐私） */
  #main>.section:nth-of-type(6){order:8}   /* downloadbox */
  #main>.section:nth-of-type(7){order:9}   /* faq */
  #main>.section:nth-of-type(8){order:10}  /* langs */
}

/* ---- B. 底部固定下载栏（stickybar） ---------------------------------------
   要素：
     * 桌面不显示（display:none），≤600px 才启用
     * 首屏不出现 —— 初始 hidden，滚动 > 400px 由 app.js 揭示
     * safe-area-inset-bottom：viewport meta 已带 viewport-fit=cover，
       不加这条会被 iPhone 的 Home Indicator 遮住按钮
     * body.has-stickybar 补 padding-bottom，避免遮住页脚最后一行 */
.stickybar{display:none}
@media (max-width:600px){
  .stickybar{
    position:fixed;left:0;right:0;bottom:0;z-index:70;
    background:rgba(7,19,31,.96);backdrop-filter:blur(12px);
    border-top:1px solid rgba(255,255,255,.10);
    padding:10px 14px calc(10px + env(safe-area-inset-bottom));
    color:#fff;
  }
  .stickybar[hidden]{display:none}
  .sb-in{display:flex;align-items:center;justify-content:space-between;gap:12px}
  .sb-brand{font-size:12.5px;font-weight:700;color:#9db0c9;white-space:nowrap;
    overflow:hidden;text-overflow:ellipsis}
  .sb-btn{padding:11px 18px;font-size:14px;flex:0 0 auto}
  body.has-stickybar{padding-bottom:78px}
  html[dir="rtl"] .sb-in{flex-direction:row-reverse}
}

/* ---- C. 下载页信任区（verify 面板内的可展开块） ---------------------------
   与站内 .faq 同款原生 <details>，无 JS 依赖；沿用 .hashrow/.copybtn 结构，
   使 app.js 里已有的复制逻辑**零改动**即可生效。 */
.trustacc{margin-top:18px;display:grid;gap:10px}
.trustacc details{background:var(--soft);border:1px solid var(--line);border-radius:14px;padding:2px 18px}
.trustacc summary{cursor:pointer;padding:15px 0;font-weight:800;font-size:15.5px;list-style:none;
  display:flex;justify-content:space-between;gap:14px;align-items:center}
.trustacc summary::-webkit-details-marker{display:none}
.trustacc summary:after{content:"+";font-size:19px;color:var(--brand);font-weight:800;flex:0 0 auto}
.trustacc details[open] summary:after{content:"\2013"}
.trustacc .tbody{padding:2px 0 16px;font-size:14.5px;color:var(--muted)}
.trustacc .tbody p{margin:0 0 9px}
.trustacc .concept{border-inline-start:3px solid var(--brand);padding-inline-start:11px;margin:12px 0}
.trustacc code{font-family:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace}
html[dir="rtl"] .trustacc summary{flex-direction:row-reverse;text-align:right}

/* 概念对照表：SHA-256（文件完整性）vs 证书指纹（发布者身份）—— 两者不可混用 */
.conceptgrid{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:8px}
.conceptgrid>div{background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px}
.conceptgrid .ck{font-size:11.5px;letter-spacing:.12em;text-transform:uppercase;font-weight:800;color:var(--brand-d)}
.conceptgrid .cv{font-size:14px;color:var(--ink);margin-top:5px}
.conceptgrid .cd{font-size:13px;color:var(--muted);margin-top:4px}
/* 信任区内每条哈希：小标题 + .hashrow（复用已有复制按钮）+ 说明 + 命令 */
.trustacc .thash{margin-top:14px}
.trustacc .thash:first-child{margin-top:4px}
.trustacc .thash-k{font-size:13px;font-weight:800;color:var(--ink);letter-spacing:.01em}
.trustacc .thash-how{font-size:13.5px;color:var(--muted);margin:9px 0 0;line-height:1.6}
.trustacc .thash-cmd{margin:8px 0 0}
.trustacc .thash-cmd code{display:inline-block;background:#fff;border:1px solid var(--line);
  border-radius:9px;padding:7px 11px;font-size:12.5px;color:var(--ink)}
/* 概念对照卡的第一行（.ck）用标签文案，较长时允许折行不撑破 */
.conceptgrid .ck{word-break:break-word}
@media (max-width:600px){
  .conceptgrid{grid-template-columns:1fr}
  .trustacc code{font-size:12px}
}