*,*::before,*::after{box-sizing:border-box;margin:0;padding:0;}

:root{
  --blue:#007aff;
  --bg:#f2f2f7;
  --s1:#ffffff;
  --s2:#ebebf0;
  --l1:#000000;
  --l2:rgba(60,60,67,.82);
  --l3:rgba(60,60,67,.58);
  --l4:rgba(60,60,67,.32);
  --sep:rgba(60,60,67,.10);
  --card-shadow:0 1px 2px rgba(0,0,0,.04),0 6px 18px rgba(0,0,0,.06),0 0 0 0.5px rgba(0,0,0,.04);
  --rc:20px;
  --r-md:16px;
  --r-sm:12px;
  --gutter:16px;
  --safe-top:env(safe-area-inset-top,0px);
  --safe-bot:env(safe-area-inset-bottom,0px);
  --safe-l:env(safe-area-inset-left,0px);
  --safe-r:env(safe-area-inset-right,0px);
}

[data-theme="dark"]{
  --bg:#000000;
  --s1:#1c1c1e;
  --s2:#2c2c2e;
  --l1:#ffffff;
  --l2:rgba(235,235,245,.82);
  --l3:rgba(235,235,245,.60);
  --l4:rgba(235,235,245,.36);
  --sep:rgba(235,235,245,.10);
  --card-shadow:0 1px 2px rgba(0,0,0,.30),0 6px 18px rgba(0,0,0,.40),0 0 0 0.5px rgba(255,255,255,.05);
}

html{-webkit-tap-highlight-color:transparent;scroll-behavior:smooth;}
html,body{overflow-x:clip;}

body{
  font-family:-apple-system,BlinkMacSystemFont,"SF Pro Display","SF Pro Text","Helvetica Neue",Arial,sans-serif;
  background:var(--bg);
  color:var(--l1);
  min-height:100vh;
  min-width:0;
  padding-bottom:calc(56px + var(--safe-bot));
  padding-left:var(--safe-l);
  padding-right:var(--safe-r);
  -webkit-font-smoothing:antialiased;
}

.page{max-width:680px;margin:0 auto;padding:0 var(--gutter);}

@media (max-width:480px){
  :root{--gutter:14px;}
}

.nav{
  display:flex;align-items:center;
  padding:calc(14px + var(--safe-top)) 0 6px;
  gap:4px;
}
.back-btn{
  display:flex;align-items:center;gap:4px;
  background:none;border:none;
  color:var(--blue);font-size:17px;font-family:inherit;font-weight:500;
  cursor:pointer;padding:6px 4px;min-height:44px;
  border-radius:10px;
  -webkit-tap-highlight-color:transparent;
  transition:opacity .15s,background .15s;
}
.back-btn:hover{opacity:.78;}
.back-btn:active{opacity:.6;}
.back-btn:focus-visible{outline:none;box-shadow:0 0 0 3px rgba(0,122,255,.28);}
.back-chevron{font-size:22px;font-weight:300;line-height:1;}

.theme-toggle{
  margin-left:auto;
  background:var(--s2);border:none;
  width:40px;height:40px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;
  font-size:18px;cursor:pointer;
  -webkit-tap-highlight-color:transparent;
  transition:opacity .15s,background .2s,transform .15s;
}
.theme-toggle:hover{background:var(--sep);}
.theme-toggle:active{opacity:.7;transform:scale(.92);}
.theme-toggle:focus-visible{outline:none;box-shadow:0 0 0 3px rgba(0,122,255,.28);}

.page-header{padding:12px 0 4px;}
.page-meta{
  display:flex;align-items:center;gap:10px;
  margin-bottom:10px;
}
.page-tag{
  font-size:11px;font-weight:600;
  color:var(--blue);letter-spacing:.8px;
  text-transform:uppercase;
}
.page-stand{
  font-size:11px;
  color:var(--l4);
  letter-spacing:.2px;
}
.page-title{
  font-size:36px;font-weight:700;
  letter-spacing:-.9px;line-height:1.08;
  padding-bottom:10px;
}
.page-subtitle{
  font-size:15.5px;
  color:var(--l3);
  line-height:1.55;
  padding-bottom:8px;
}
@media (max-width:480px){
  .page-title{font-size:30px;letter-spacing:-.7px;}
  .page-subtitle{font-size:15px;}
}

.card{
  background:var(--s1);
  border-radius:var(--rc);
  box-shadow:var(--card-shadow);
  padding:24px 22px 22px;
  margin-top:14px;
}

.card-icon{
  width:42px;height:42px;border-radius:var(--r-sm);
  background:var(--s2);
  display:flex;align-items:center;justify-content:center;
  margin-bottom:14px;
  color:var(--l2);
}

h2{
  font-size:17.5px;font-weight:600;
  color:var(--l1);
  margin-bottom:12px;
  letter-spacing:-.25px;
}

p{
  font-size:15.5px;
  line-height:1.72;
  color:var(--l2);
}
p + p{margin-top:12px;}

strong{color:var(--l1);font-weight:500;}
a{color:var(--blue);text-decoration:none;}
a:hover{text-decoration:underline;}

.footer{
  text-align:center;
  padding:44px 0 16px;
  font-size:12.5px;
}
.footer-links{
  display:flex;justify-content:center;align-items:center;
  gap:4px 10px;flex-wrap:wrap;margin-bottom:10px;
  max-width:560px;margin-left:auto;margin-right:auto;
}
.footer-links a{
  color:var(--l3);
  text-decoration:none;
  padding:8px 6px;
  border-radius:8px;
  min-height:36px;
  display:inline-flex;align-items:center;
  -webkit-tap-highlight-color:transparent;
}
.footer-links a:hover{color:var(--l2);text-decoration:underline;}
.footer-links a:active{color:var(--l1);background:var(--s2);}
.footer-links span{color:var(--l4);user-select:none;}
.footer-note{color:var(--l4);line-height:1.7;max-width:380px;margin:0 auto;}

@media (max-width:480px){
  .nav{padding-top:calc(12px + var(--safe-top));}
  .page-header{padding:10px 0 4px;}
  .card{padding:20px 18px 18px;margin-top:12px;}
  .card-icon{width:40px;height:40px;margin-bottom:12px;}
  h2{font-size:16.5px;}
  p{font-size:15px;line-height:1.7;}
  .footer{padding:36px 0 14px;font-size:12px;}
}
@media (max-width:375px){
  :root{--gutter:12px;}
  .page-title{font-size:27px;letter-spacing:-.6px;}
  .page-subtitle{font-size:14.5px;}
  .card{padding:18px 16px 16px;}
  .back-btn{font-size:16px;}
  .theme-toggle{width:38px;height:38px;font-size:16px;}
}