/* 全站：颜色从 App 来（web/public/app.css）。字也和 App 一套：标题 Newsreader（350，比 400 轻一点，大字不压眼睛），正文系统字体（D35）；Newsreader 斜体只留给答案的声音。 */
:root{
  --bg:#f4eee1;--card:#fbf8f1;--ink:#26241f;--ink2:#57524a;--ink3:#6e685b;--accent:#3e4f7b;--on-accent:#fbf8f1;--tint:color-mix(in srgb,#3e4f7b 11%,transparent);
  --serif:"Newsreader","Iowan Old Style",Georgia,serif;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"PingFang SC","PingFang TC","Noto Sans SC","Microsoft YaHei",sans-serif;
  --max:1360px;--g:clamp(20px,5vw,72px);
  --ease:cubic-bezier(.16,1,.3,1);
  color-scheme:light;
}
.on-night{--bg:#24211d;--card:#2d2924;--ink:#efe8d8;--ink2:#cfc7b6;--ink3:#a39b8a;--accent:#e8e1d1;--on-accent:#24211d;--tint:color-mix(in srgb,#e8e1d1 12%,transparent);color:var(--ink)}
@media (prefers-color-scheme:dark){:root{--bg:#24211d;--card:#2d2924;--ink:#efe8d8;--ink2:#cfc7b6;--ink3:#a39b8a;--accent:#e8e1d1;--on-accent:#24211d;color-scheme:dark}}

*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scrollbar-color:color-mix(in srgb,var(--ink3) 55%,transparent) transparent}
body{margin:0;min-height:100svh;background:var(--bg-now,var(--bg));color:var(--ink);font:400 17px/1.55 var(--sans);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;overflow-x:clip;transition:background-color .6s}
img,picture,canvas{display:block;max-width:100%}
img{height:auto}
a{color:inherit}
::selection{background:color-mix(in srgb,var(--accent) 24%,transparent)}
input{caret-color:var(--accent)}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:4px}

/* 字号收着，字距和行距给够：标题要好读，不要把版面塞满 */
h1,h2,h3{margin:0;font-family:var(--serif);font-weight:350;color:var(--ink);text-wrap:balance}
h1{font-size:clamp(38px,4.4vw,64px);line-height:1.1;letter-spacing:-.012em}
h2{font-size:clamp(30px,3.2vw,46px);line-height:1.14;letter-spacing:-.01em}
h3{font-size:clamp(21px,1.7vw,24px);line-height:1.25;letter-spacing:-.004em}
p{margin:0;text-wrap:pretty}
.lede{color:var(--ink2);font-size:clamp(17px,1.3vw,19px);line-height:1.55;max-width:46ch}
.tl{color:var(--accent);text-decoration:underline;text-underline-offset:.28em;text-decoration-thickness:1px;text-decoration-color:color-mix(in srgb,var(--accent) 38%,transparent);transition:text-decoration-color .25s}
.tl:hover{text-decoration-color:var(--accent)}
.vh{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
.skip{position:fixed;left:12px;top:-60px;z-index:20;padding:10px 16px;border-radius:24px;background:var(--accent);color:var(--on-accent);transition:top .2s}
.skip:focus{top:12px}
.wrap{width:100%;max-width:var(--max);margin-inline:auto;padding-inline:var(--g)}
#sky{position:fixed;inset:0;width:100vw;height:100lvh;z-index:-1;opacity:0;transition:opacity .5s}
#sky.on{opacity:1}
main,header,footer{position:relative}

/* 按钮：和 App 同一块喷出来的色，不描边 */
.btn{position:relative;isolation:isolate;display:inline-flex;align-items:center;justify-content:center;min-height:52px;padding:8px 30px;border:0;border-radius:27px;background-color:var(--accent);color:var(--on-accent);font:500 16px/1.2 var(--sans);text-decoration:none;white-space:nowrap;cursor:pointer;transition:scale .3s var(--ease)}
.btn::before{content:"";position:absolute;inset:-12px;z-index:-1;pointer-events:none;background:var(--bm) center/100% 100% no-repeat;opacity:0;transition:opacity .5s}
.btn.m{background-color:transparent}.btn.m::before{opacity:1}
.btn:hover{scale:1.025}.btn:active{scale:.98}
/* 次要按钮：淡淡一层底色，不描边，不喷深色（App 的 .btn.soft 同款） */
.btn.soft{min-height:44px;padding:6px 20px;background-color:var(--tint);color:var(--accent);font-size:15px}
.btn.soft:hover{background-color:color-mix(in srgb,var(--accent) 18%,transparent)}
.btn:disabled{cursor:default;opacity:.55;scale:1}
.cta{display:flex;flex-wrap:wrap;align-items:center;gap:14px 22px}
.cta-note{color:var(--ink3);font-size:15px}

/* 导航：只放真的页面 */
.nav{position:absolute;inset:0 0 auto 0;z-index:5;display:flex;align-items:center;justify-content:space-between;padding-block:clamp(18px,2.2vw,28px)}
.nav-word{flex-shrink:0}
.nav-word img{width:auto;height:30px}
.nav-links{display:flex;align-items:center;gap:clamp(16px,2.4vw,28px);font-size:16px}
.nav-links .btn{min-height:42px;padding:6px 20px;font-size:15px;margin-left:clamp(2px,1vw,10px)}
/* 语言切换：地球 + 另一种语言，灰一点，不和 Sign in 抢 */
.nav-links .nav-lang{gap:6px;color:var(--ink2);font-weight:400;font-size:15px;margin-right:clamp(0px,.6vw,6px)}
.nav-links .nav-lang svg{flex:none}
.nav-links .nav-lang:hover{color:var(--ink)}
.nav-links a{min-height:44px;display:inline-flex;align-items:center;white-space:nowrap;text-decoration:none;color:var(--accent);font-weight:500;text-underline-offset:.3em;text-decoration-thickness:1px}
.nav-links a:hover{text-decoration-line:underline}

/* 页脚 */
/* 页脚：左边字标和一句话，右边站内的页；下面一行版权，再一行提醒 */
.foot{display:grid;grid-template-columns:auto 1fr;grid-template-areas:"brand links" "copy copy" "note note";gap:22px 48px;align-items:start;padding-block:clamp(56px,6vw,88px) calc(clamp(28px,3vw,44px) + env(safe-area-inset-bottom));color:var(--ink)}
.foot-brand{grid-area:brand}
.foot-mark{display:inline-flex;align-items:center;gap:14px;text-decoration:none}
.foot-tagline{margin-top:14px;color:var(--ink2);font-size:15px}
.foot-links{grid-area:links}
.foot-copy{grid-area:copy;margin-top:18px;color:var(--ink3);font-size:14.5px}
.foot-note{grid-area:note}
.foot-word img{width:auto;height:26px}
.foot-seal img{width:auto;height:44px}
.foot-links{display:flex;flex-wrap:wrap;justify-content:flex-end;gap:6px 28px;font-size:16px}
.foot-links a{min-height:44px;display:inline-flex;align-items:center;text-decoration:none;color:var(--ink2);text-underline-offset:.3em;text-decoration-thickness:1px;transition:color .2s}
.foot-links a:hover{color:var(--ink);text-decoration-line:underline}
.foot-note{max-width:62ch;color:var(--ink3);font-size:14.5px;line-height:1.5}

/* 普通页：FAQ、隐私、Blog、404 */
.page{padding-block:clamp(128px,14vw,190px) clamp(48px,6vw,88px);max-width:calc(820px + var(--g)*2);margin-inline:0;margin-left:max(0px,calc((100vw - var(--max))/2))}
.page-head{margin-bottom:clamp(44px,5vw,72px)}
.page-head h1{font-size:clamp(36px,3.8vw,52px);margin-bottom:16px}
.stamp{color:var(--ink3);font-size:15.5px}
.page-head .stamp:first-child{margin-bottom:20px}
.qa{margin-bottom:56px}
.qa details{border-radius:18px;margin-inline:-20px;padding-inline:20px;transition:background-color .25s}
.qa details+details{margin-top:4px}
.qa details[open]{background:color-mix(in srgb,var(--card) 62%,transparent)}
.qa summary{display:flex;justify-content:space-between;align-items:baseline;gap:20px;min-height:56px;padding-block:17px;font:350 clamp(20px,1.6vw,23px)/1.3 var(--serif);cursor:pointer;list-style:none}
.qa summary::-webkit-details-marker{display:none}
.qa summary::after{content:"";flex:none;width:11px;height:11px;margin-right:3px;translate:0 -3px;rotate:45deg;background:var(--ink3);clip-path:polygon(100% 0,100% 100%,0 100%,0 74%,74% 74%,74% 0);transition:rotate .35s var(--ease),translate .35s var(--ease)}
.qa details[open] summary::after{rotate:225deg;translate:0 4px}
.qa details p{padding-bottom:24px;color:var(--ink2);max-width:60ch}
.prose{max-width:62ch}
.prose h2{font-size:clamp(23px,1.9vw,27px);line-height:1.25;margin-top:clamp(36px,4vw,52px);margin-bottom:12px}
.prose h3{font-size:21px;margin-top:32px;margin-bottom:10px}
.prose p,.prose ul,.prose blockquote{color:var(--ink2);margin:0 0 18px}
.prose ul{padding-left:1.1em}.prose li{margin-bottom:8px}
.prose strong{font-weight:500;color:var(--ink)}
.prose blockquote{margin-block:26px;font:italic 350 clamp(21px,1.7vw,24px)/1.36 var(--serif);color:var(--ink)}
.post-end{margin-top:clamp(56px,6vw,88px)}
.post-q{font:350 clamp(26px,2.3vw,32px)/1.2 var(--serif);margin-bottom:22px}
.posts{list-style:none;margin:0;padding:0}
.posts li+li{margin-top:clamp(36px,4vw,52px)}
.posts a{display:block;text-decoration:none}
.posts h2{font-size:clamp(24px,2.1vw,30px);line-height:1.2;margin-bottom:10px;transition:color .2s}
.posts a:hover h2{color:var(--accent)}
.posts p{color:var(--ink2);max-width:58ch}
.posts .stamp{margin-top:10px;color:var(--ink3)}
.page-nf{min-height:72svh}
.page-nf h1{margin-bottom:20px}
.page-nf .lede{margin-bottom:32px}

@media (max-width:640px){
  .foot{grid-template-columns:1fr;grid-template-areas:"brand" "links" "copy" "note";gap:26px}
  .foot-links{justify-content:flex-start}
  .foot-copy{margin-top:4px}
  .nav-links{gap:14px}
  .nav-links .btn{padding:6px 16px;margin-left:0}
  .qa details{margin-inline:-12px;padding-inline:12px}
}
/* 中文：标题用宋体一路（和 App 一样），不用斜体，字距放平，行距松一点 */
html[lang^="zh"]{--serif:"Noto Serif SC","Songti SC","STSong","Source Han Serif SC","Noto Serif CJK SC",serif}
/* 中文标题只在标点和空格处断行（keep-all），一行放不下才任意断（anywhere）：不再出现“屏 / 幕”这种断法 */
html[lang^="zh"] h1,html[lang^="zh"] h2,html[lang^="zh"] h3{letter-spacing:.01em;font-weight:400;text-wrap:balance;word-break:keep-all;overflow-wrap:anywhere}
html[lang^="zh"] .lede,html[lang^="zh"] p{line-height:1.8}
html[lang^="zh"] .ans-a,html[lang^="zh"] .s7-lead,html[lang^="zh"] em{font-style:normal}
@media (max-width:480px){
  .nav-links .nav-lang span{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}
  .nav-links .nav-lang{margin-right:0}
}
@media (max-width:400px){
  .nav-word img{height:26px}
  .nav-links{gap:12px}
  .nav-links .btn{min-height:38px;padding:6px 14px;font-size:14px}
}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{transition-duration:.01ms!important;animation-duration:.01ms!important;scroll-behavior:auto!important}}