:root{
  --ink-900:#061713;
  --night-800:#0C2136;
  --paper-50:#F3F0E7;
  --paper-200:#DCD6C6;
  --cyan-400:#38F2D6;
  --amber-500:#FF8A3D;
  --silver-300:#C6CDD4;
  --grass-500:#33C06A;
  --lemon-400:#D8F24E;
  --signal-500:#FF4D5E;
  --line-600:#26363F;

  --font-display:"PingFang SC","HarmonyOS Sans SC","Source Han Sans SC","Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;
  --font-body:var(--font-display);
  --font-num:ui-monospace,"SF Mono","JetBrains Mono","Cascadia Mono",Menlo,Consolas,"Liberation Mono",monospace;

  --wrap-max:1280px;
  --gut:clamp(16px,3vw,32px);
  --r-sm:4px;
  --r-md:10px;
  --r-pill:999px;
  --ease:cubic-bezier(.2,.7,.3,1);
  --d-1:.18s;
  --d-2:.38s;
}

*,*::before,*::after{box-sizing:border-box;}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;}
body{
  margin:0;
  min-height:100vh;
  font-family:var(--font-body);
  font-size:15px;
  line-height:1.68;
  letter-spacing:.01em;
  color:var(--paper-50);
  background-color:var(--ink-900);
  background-image:
    radial-gradient(90% 60% at 6% 0%,rgba(56,242,214,.065),transparent 62%),
    radial-gradient(72% 52% at 100% 10%,rgba(12,33,54,.9),transparent 72%);
  background-repeat:no-repeat;
  -webkit-font-smoothing:antialiased;
}
body::before{
  content:"";
  position:fixed;
  inset:0;
  z-index:0;
  pointer-events:none;
  background-image:
    repeating-linear-gradient(0deg,rgba(198,205,212,.035) 0 1px,transparent 1px 3px),
    repeating-linear-gradient(90deg,rgba(56,242,214,.028) 0 1px,transparent 1px 64px);
  opacity:.85;
}
main{position:relative;z-index:1;}
img,svg{max-width:100%;}
@media (min-width:768px){body{font-size:16px;}}

h1,h2,h3,h4{
  margin:0 0 .55em;
  font-family:var(--font-display);
  font-weight:800;
  font-stretch:condensed;
  letter-spacing:-.02em;
  line-height:1.16;
  text-align:left;
}
h1{font-size:clamp(2.2rem,5vw,4rem);}
h2{font-size:clamp(1.5rem,2.6vw,2.2rem);}
h3{font-size:1.15rem;letter-spacing:-.01em;}
p{margin:0 0 1em;}
a{color:var(--cyan-400);text-decoration:none;}
a:hover{text-decoration:underline;text-underline-offset:3px;}
ul,ol{margin:0;padding:0;}
li{list-style:none;}
strong{color:var(--paper-50);}
:focus-visible{outline:2px solid var(--cyan-400);outline-offset:2px;border-radius:2px;}

.num{
  font-family:var(--font-num);
  font-variant-numeric:tabular-nums;
  letter-spacing:-.01em;
  white-space:nowrap;
}

.wrap{
  position:relative;
  z-index:1;
  width:100%;
  max-width:var(--wrap-max);
  margin-inline:auto;
  padding-inline:var(--gut);
}
.narrow{max-width:820px;margin-inline:auto;}
.grid-12{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:24px;}
.lede{font-size:1.05rem;color:var(--paper-200);max-width:62ch;}
.muted{color:var(--silver-300);font-size:.82rem;}

.crumbs{display:flex;flex-wrap:wrap;align-items:center;gap:8px;font-size:.76rem;color:var(--silver-300);}
.crumbs li{display:flex;align-items:center;gap:8px;}
.crumbs li+li::before{content:"/";color:var(--line-600);}
.crumbs a{color:var(--silver-300);text-decoration:none;border-bottom:1px solid transparent;}
.crumbs a:hover{color:var(--cyan-400);border-bottom-color:var(--cyan-400);text-decoration:none;}
.crumbs [aria-current="page"]{color:var(--paper-50);}

.btn{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:11px 18px;
  border:1px solid var(--cyan-400);
  border-radius:0;
  background:transparent;
  color:var(--cyan-400);
  font:inherit;
  font-weight:600;
  font-size:.86rem;
  letter-spacing:.02em;
  text-decoration:none;
  clip-path:polygon(0 0,100% 0,100% calc(100% - 10px),calc(100% - 10px) 100%,0 100%);
  transition:background-color var(--d-1) var(--ease),color var(--d-1) var(--ease),border-color var(--d-1) var(--ease);
}
.btn:hover,.btn:focus-visible{background:var(--cyan-400);color:var(--ink-900);text-decoration:none;}
.btn-line{border-color:var(--line-600);color:var(--paper-50);}
.btn-line:hover,.btn-line:focus-visible{background:var(--paper-50);border-color:var(--paper-50);color:var(--ink-900);}
.btn-amber{border-color:var(--amber-500);color:var(--amber-500);}
.btn-amber:hover,.btn-amber:focus-visible{background:var(--amber-500);border-color:var(--amber-500);color:var(--ink-900);}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 9px;
  font-size:.72rem;
  letter-spacing:.08em;
  line-height:1.5;
  border:1px solid var(--line-600);
  border-radius:var(--r-sm);
  color:var(--silver-300);
  background:rgba(12,33,54,.6);
}
.tag--paper{background:var(--paper-50);color:#0A1C17;border-color:var(--paper-200);}
.tag--cyan{border-color:var(--cyan-400);color:var(--cyan-400);}
.tag--amber{border-color:var(--amber-500);color:var(--amber-500);}

.card{
  position:relative;
  padding:20px;
  border:1px solid var(--line-600);
  background:linear-gradient(160deg,rgba(12,33,54,.9),rgba(6,23,19,.94));
  clip-path:polygon(0 0,100% 0,100% calc(100% - 16px),calc(100% - 16px) 100%,0 100%);
}
.card--paper{background:var(--paper-50);color:#0A1C17;border-color:var(--paper-200);}
.card--paper h3,.card--paper strong{color:#0A1C17;}
.card--paper a{color:#0F5F4E;}

.figure{
  position:relative;
  margin:0;
  overflow:hidden;
  aspect-ratio:16/9;
  border:1px solid var(--line-600);
  background:linear-gradient(155deg,var(--night-800),var(--ink-900));
}
.figure img{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
  filter:saturate(.85) contrast(1.08) brightness(.9);
}
.figure::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    repeating-linear-gradient(0deg,rgba(56,242,214,.09) 0 1px,transparent 1px 24px),
    repeating-linear-gradient(90deg,rgba(56,242,214,.07) 0 1px,transparent 1px 24px);
  mix-blend-mode:screen;
}
.figure--wide{aspect-ratio:21/9;}
.figure--tall{aspect-ratio:4/5;}
.figure--square{aspect-ratio:1/1;}
.figure figcaption{
  position:absolute;
  left:0;right:0;bottom:0;
  padding:10px 14px;
  font-size:.75rem;
  color:var(--paper-50);
  background:linear-gradient(0deg,rgba(6,23,19,.94),rgba(6,23,19,0));
}

.viewfinder{position:relative;}
.viewfinder::before{
  content:"";
  position:absolute;
  inset:10px;
  pointer-events:none;
  opacity:.72;
  background:
    linear-gradient(var(--cyan-400),var(--cyan-400)) 0 0/18px 2px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 0 0/2px 18px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 100% 0/18px 2px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 100% 0/2px 18px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 0 100%/18px 2px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 0 100%/2px 18px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 100% 100%/18px 2px no-repeat,
    linear-gradient(var(--cyan-400),var(--cyan-400)) 100% 100%/2px 18px no-repeat;
}

.data-table{width:100%;border-collapse:collapse;font-size:.86rem;}
.data-table caption{
  caption-side:top;
  text-align:left;
  font-size:.72rem;
  letter-spacing:.08em;
  color:var(--silver-300);
  padding-bottom:8px;
}
.data-table th,.data-table td{
  padding:10px 12px;
  text-align:left;
  border-bottom:1px solid var(--line-600);
  vertical-align:top;
}
.data-table th{font-size:.72rem;letter-spacing:.08em;color:var(--silver-300);font-weight:600;}
.data-table tbody tr:hover td:first-child{box-shadow:inset 2px 0 0 var(--cyan-400);}
.data-table tfoot td{font-size:.74rem;color:var(--silver-300);border-bottom:none;}

.band{
  position:relative;
  padding-block:28px;
  border-top:1px solid var(--line-600);
  border-bottom:1px solid var(--line-600);
  background:linear-gradient(90deg,rgba(12,33,54,.95),rgba(6,23,19,.72));
}

.chapter{position:relative;padding-block:clamp(48px,7vw,96px);}
.chapter-head{display:flex;align-items:baseline;gap:16px;margin-bottom:22px;flex-wrap:wrap;}
.chapter-index{
  display:inline-block;
  padding:4px 9px;
  font-family:var(--font-num);
  font-size:.78rem;
  letter-spacing:.12em;
  color:var(--silver-300);
  border:1px solid var(--line-600);
  transition:color var(--d-2) var(--ease),background-color var(--d-2) var(--ease),border-color var(--d-2) var(--ease);
}
.chapter.is-current .chapter-index{
  color:var(--ink-900);
  background:var(--cyan-400);
  border-color:var(--cyan-400);
}

html.js-on [data-reveal]{
  opacity:0;
  transform:translateY(12px);
  transition:opacity var(--d-2) var(--ease),transform var(--d-2) var(--ease);
}
html.js-on [data-reveal].is-in{opacity:1;transform:none;}

/* ===================== header ===================== */
.site-head{
  position:sticky;
  top:0;
  z-index:80;
  padding:14px 16px 0;
  transition:padding var(--d-2) var(--ease);
}
.site-head.is-compact{padding-top:6px;}

.head-bar{
  position:absolute;
  top:0;left:0;right:0;
  height:2px;
  background:rgba(38,54,63,.9);
  z-index:2;
}
.head-bar-fill{
  display:block;
  height:100%;
  width:100%;
  transform:scaleX(0);
  transform-origin:left center;
  background:linear-gradient(90deg,var(--cyan-400),var(--grass-500) 58%,var(--lemon-400));
}

.head-inner{
  position:relative;
  z-index:1;
  display:flex;
  align-items:center;
  gap:14px;
  width:100%;
  max-width:var(--wrap-max);
  margin-inline:auto;
  padding:10px 14px 10px 18px;
  border:1px solid var(--line-600);
  border-radius:var(--r-pill);
  background:linear-gradient(100deg,rgba(6,23,19,.95),rgba(12,33,54,.9) 56%,rgba(6,23,19,.95));
  box-shadow:0 22px 54px -36px rgba(0,0,0,.96);
  backdrop-filter:blur(12px);
  -webkit-backdrop-filter:blur(12px);
  transition:padding var(--d-2) var(--ease);
}
.site-head.is-compact .head-inner{padding:6px 12px 6px 14px;}

.skip-link{
  position:absolute;
  left:16px;
  top:-60px;
  z-index:200;
  padding:10px 16px;
  background:var(--cyan-400);
  color:var(--ink-900);
  font-weight:700;
  font-size:.85rem;
  text-decoration:none;
  border-radius:var(--r-sm);
  transition:top var(--d-1) var(--ease);
}
.skip-link:focus{top:12px;text-decoration:none;}

.brand{
  display:flex;
  align-items:center;
  gap:10px;
  margin-right:auto;
  min-width:0;
  color:var(--paper-50);
  text-decoration:none;
}
.brand:hover{text-decoration:none;color:var(--paper-50);}
.brand-dot{
  flex:none;
  width:11px;height:11px;
  background:var(--cyan-400);
  clip-path:polygon(0 0,100% 0,100% 68%,68% 100%,0 100%);
  box-shadow:0 0 0 3px rgba(56,242,214,.16);
}
.brand-text{display:inline-flex;align-items:center;gap:7px;min-width:0;}
.brand-name{
  font-family:var(--font-display);
  font-weight:900;
  font-stretch:condensed;
  font-size:1.12rem;
  letter-spacing:-.02em;
  white-space:nowrap;
}
.brand-ver{
  font-family:var(--font-num);
  font-size:.68rem;
  letter-spacing:.08em;
  padding:2px 6px;
  border:1px solid var(--cyan-400);
  color:var(--cyan-400);
  border-radius:var(--r-sm);
}
.brand-tag{
  font-size:.72rem;
  color:var(--silver-300);
  padding-left:12px;
  margin-left:2px;
  border-left:1px solid var(--line-600);
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}

.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:8px 13px;
  border:1px solid var(--line-600);
  border-radius:var(--r-pill);
  background:transparent;
  color:var(--paper-50);
  font:inherit;
  font-size:.82rem;
  cursor:pointer;
}
.nav-toggle:hover{border-color:var(--cyan-400);color:var(--cyan-400);}
.nav-toggle-lines{position:relative;display:inline-block;width:16px;height:10px;}
.nav-toggle-lines::before,
.nav-toggle-lines::after{
  content:"";
  position:absolute;
  left:0;
  width:100%;
  height:1.5px;
  background:currentColor;
  transition:transform var(--d-1) var(--ease),top var(--d-1) var(--ease);
}
.nav-toggle-lines::before{top:1px;}
.nav-toggle-lines::after{top:7px;}
.nav-toggle[aria-expanded="true"] .nav-toggle-lines::before{top:4px;transform:rotate(45deg);}
.nav-toggle[aria-expanded="true"] .nav-toggle-lines::after{top:4px;transform:rotate(-45deg);}

.site-nav{margin-left:auto;}
.nav-list{display:flex;align-items:center;gap:2px;}
.nav-link{
  display:inline-block;
  padding:8px 12px;
  border-radius:var(--r-pill);
  font-size:.86rem;
  color:var(--paper-50);
  text-decoration:none;
  white-space:nowrap;
  transition:background-color var(--d-1) var(--ease),color var(--d-1) var(--ease);
}
.nav-link:hover{background:rgba(56,242,214,.12);color:var(--cyan-400);text-decoration:none;}
.nav-link[aria-current="page"]{background:var(--cyan-400);color:var(--ink-900);font-weight:700;}
.nav-link[aria-current="page"]:hover{background:var(--cyan-400);color:var(--ink-900);}

.head-quick{
  display:inline-flex;
  align-items:baseline;
  gap:7px;
  padding:8px 15px;
  border:1px solid var(--amber-500);
  border-radius:var(--r-pill);
  color:var(--amber-500);
  font-size:.8rem;
  text-decoration:none;
  white-space:nowrap;
  transition:background-color var(--d-1) var(--ease),color var(--d-1) var(--ease);
}
.head-quick:hover{background:var(--amber-500);color:var(--ink-900);text-decoration:none;}
.head-quick-k{font-size:.68rem;letter-spacing:.08em;opacity:.78;}
.head-quick-v{font-weight:700;}

/* ===================== footer ===================== */
.site-foot{
  position:relative;
  z-index:1;
  margin-top:96px;
  padding:56px 16px 26px;
  border-top:1px solid var(--line-600);
  background:
    radial-gradient(120% 100% at 12% 0%,rgba(56,242,214,.07),transparent 60%),
    linear-gradient(180deg,var(--night-800),var(--ink-900) 58%);
}
.foot-wrap{
  width:100%;
  max-width:var(--wrap-max);
  margin-inline:auto;
}
.foot-sheet{
  position:relative;
  z-index:0;
  display:grid;
  grid-template-columns:minmax(0,1fr) minmax(0,2.35fr);
  gap:40px;
  padding:32px clamp(18px,3vw,36px);
  border:1px solid var(--line-600);
  border-radius:var(--r-sm);
  background:linear-gradient(180deg,rgba(243,240,231,.058),rgba(243,240,231,.018));
}
.foot-sheet::before{
  content:"";
  position:absolute;
  inset:10px 7px -10px 7px;
  z-index:-1;
  background:rgba(243,240,231,.035);
  border:1px solid rgba(38,54,63,.85);
  border-radius:var(--r-sm);
}
.foot-brand{display:flex;flex-direction:column;align-items:flex-start;gap:12px;}
.foot-mark{
  margin:0;
  font-family:var(--font-display);
  font-weight:900;
  font-stretch:condensed;
  font-size:1.22rem;
  letter-spacing:-.02em;
  color:var(--paper-50);
}
.foot-tag{margin:0;font-size:.82rem;color:var(--silver-300);max-width:30ch;}
.foot-cols{
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:28px 22px;
}
.foot-col{min-width:0;}
.foot-col-title{
  margin:0 0 14px;
  padding-top:12px;
  border-top:2px solid var(--line-600);
  font-size:.74rem;
  font-weight:700;
  letter-spacing:.1em;
  color:var(--silver-300);
  font-size:.74rem;
}
.foot-col:nth-child(1) .foot-col-title{border-top-color:var(--cyan-400);}
.foot-col:nth-child(2) .foot-col-title{border-top-color:var(--amber-500);}
.foot-col:nth-child(3) .foot-col-title{border-top-color:var(--silver-300);}
.foot-col:nth-child(4) .foot-col-title{border-top-color:var(--grass-500);}
.foot-list{display:grid;gap:8px;}
.foot-list a{
  font-size:.86rem;
  color:var(--paper-50);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color var(--d-1) var(--ease),border-color var(--d-1) var(--ease);
}
.foot-list a:hover{color:var(--cyan-400);border-bottom-color:var(--cyan-400);text-decoration:none;}
.foot-contact{display:grid;gap:10px;}
.foot-contact li{
  display:grid;
  grid-template-columns:72px minmax(0,1fr);
  gap:10px;
  font-size:.82rem;
}
.foot-k{font-size:.72rem;letter-spacing:.06em;color:var(--silver-300);padding-top:2px;}
.foot-v{color:var(--paper-50);word-break:break-word;}
.foot-hint{margin:12px 0 0;font-size:.74rem;color:var(--silver-300);}
.foot-ruler{
  position:relative;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
  margin-top:30px;
  padding-top:18px;
  border-top:1px dashed rgba(38,54,63,.9);
  font-size:.72rem;
  letter-spacing:.08em;
  color:var(--silver-300);
}
.foot-ruler::before{
  content:"";
  position:absolute;
  top:-1px;left:0;
  width:38%;height:1px;
  background:linear-gradient(90deg,var(--cyan-400),rgba(56,242,214,0));
}
.foot-ruler-value{font-family:var(--font-num);font-variant-numeric:tabular-nums;white-space:nowrap;color:var(--paper-200);}
.foot-base{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  justify-content:space-between;
  gap:10px 24px;
  padding-top:18px;
  font-size:.76rem;
  color:var(--silver-300);
}
.foot-note{margin:0;max-width:62ch;}
.foot-copy{margin:0;}

/* ===================== responsive ===================== */
@media (max-width:1279px){
  .brand-tag{display:none;}
}
@media (min-width:1024px){
  .foot-col:nth-child(2){margin-top:18px;}
  .foot-col:nth-child(3){margin-top:8px;}
  .foot-col:nth-child(4){margin-top:26px;}
}
@media (max-width:1023px){
  .nav-toggle{display:inline-flex;}
  .site-nav{
    position:absolute;
    top:calc(100% + 12px);
    left:12px;
    right:12px;
    margin-left:0;
    padding:8px;
    border:1px solid var(--line-600);
    border-radius:16px;
    background:linear-gradient(180deg,var(--night-800),var(--ink-900));
    box-shadow:0 26px 60px -30px rgba(0,0,0,.95);
    opacity:0;
    visibility:hidden;
    transform:translateY(-8px);
    transition:opacity var(--d-1) var(--ease),transform var(--d-1) var(--ease),visibility var(--d-1) linear;
  }
  .site-nav[data-open]{
    opacity:1;
    visibility:visible;
    transform:none;
  }
  .nav-list{flex-direction:column;align-items:stretch;gap:2px;}
  .nav-link{display:block;padding:12px 14px;border-radius:var(--r-md);font-size:.92rem;}
  .head-inner{flex-wrap:nowrap;}
  .foot-sheet{grid-template-columns:minmax(0,1fr);gap:28px;}
  .foot-cols{grid-template-columns:repeat(2,minmax(0,1fr));gap:24px;}
  .grid-12{grid-template-columns:repeat(6,minmax(0,1fr));}
}
@media (max-width:719px){
  .brand-name{font-size:1rem;}
  .head-quick-k{display:none;}
  .head-quick{padding:8px 12px;font-size:.78rem;}
  .foot-cols{grid-template-columns:minmax(0,1fr);}
  .foot-base{flex-direction:column;align-items:flex-start;}
  .foot-ruler{flex-direction:column;align-items:flex-start;gap:6px;}
  .grid-12{grid-template-columns:minmax(0,1fr);gap:16px;}
}
@media (max-width:419px){
  .nav-toggle-text{display:none;}
  .nav-toggle{padding:8px 10px;}
  .brand-ver{display:none;}
}

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