/* ============ 01 RESET ============ */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,dl,dd,figure,blockquote{margin:0;padding:0}
ul,ol{list-style:none}
img,svg,video{display:block;max-width:100%}
button{background:none;border:0;font:inherit;color:inherit;cursor:pointer}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}
:focus-visible{outline:2px solid var(--amber-400);outline-offset:2px}

/* ============ 02 TOKENS ============ */
:root{
  --ink-950:#070B0A;
  --pitch-900:#0C211B;
  --pitch-700:#14453A;
  --line-500:#2A5F4E;
  --signal-600:#FF5A1F;
  --amber-400:#FFB020;
  --steel-300:#A9BDD0;
  --paper-050:#F4F7F5;
  --muted-400:#7C8C84;

  --fs-1:.75rem; --fs-2:.875rem; --fs-3:1rem; --fs-4:1.25rem;
  --fs-5:1.75rem; --fs-6:2.5rem; --fs-7:3.5rem; --fs-8:5rem;

  --font-display:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono","Sarasa Mono SC",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --shell:1180px;
  --gutter:clamp(16px,4vw,40px);
  --edge:2px solid var(--line-500);
  --edge-dark:2px solid var(--ink-950);
  --shadow-hard:6px 6px 0 0 rgba(7,11,10,.85);
  --shadow-signal:6px 6px 0 0 var(--signal-600);
  --ease:cubic-bezier(.2,.7,.3,1);
  --dur:320ms;
}

/* ============ 03 BASE / 中文排版 ============ */
body{
  background:var(--pitch-900);
  color:var(--paper-050);
  font-family:var(--font-display);
  font-size:var(--fs-3);
  font-weight:400;
  line-height:1.75;
  min-height:100vh;
  overflow-x:hidden;
}
h1,h2,h3,h4{font-weight:900;letter-spacing:-.02em;line-height:1.12}
h1{font-size:clamp(2rem,7vw,var(--fs-8))}
h2{font-size:var(--fs-5)}
h3{font-size:var(--fs-4)}
p{max-width:42em}
::selection{background:var(--signal-600);color:var(--ink-950)}
strong,b{font-weight:700}
.ps-num{
  font-family:var(--font-mono);
  font-variant-numeric:tabular-nums;
  font-feature-settings:"tnum" 1;
  letter-spacing:.02em;
}
.ps-kicker{
  display:inline-block;
  font-family:var(--font-mono);
  font-size:var(--fs-1);
  font-weight:500;
  letter-spacing:.18em;
  text-transform:uppercase;
  color:var(--amber-400);
}
.ps-lead{font-size:var(--fs-4);line-height:1.6;max-width:34em;color:var(--paper-050)}
.ps-prose{max-width:38em;color:#DDE6E1}
.ps-prose p+p{margin-top:1.1em}

/* ============ 04 LAYOUT ============ */
.ps-shell{width:100%;max-width:var(--shell);margin-inline:auto;padding-inline:var(--gutter)}
.ps-section{padding-block:clamp(40px,7vw,96px)}
.ps-grid{display:grid;grid-template-columns:repeat(12,minmax(0,1fr));gap:clamp(16px,2.4vw,32px)}
.ps-col-4,.ps-col-5,.ps-col-7,.ps-col-8,.ps-col-12{grid-column:1/-1}
.ps-offset-y{margin-top:clamp(24px,4vw,48px)}
@media (min-width:900px){
  .ps-col-4{grid-column:span 4}
  .ps-col-5{grid-column:span 5}
  .ps-col-7{grid-column:span 7}
  .ps-col-8{grid-column:span 8}
  .ps-col-12{grid-column:1/-1}
  .ps-col-7--end{grid-column:6/span 7}
  .ps-col-5--end{grid-column:8/span 5}
}
.ps-chapter{
  display:flex;align-items:baseline;gap:14px;flex-wrap:wrap;
  border-bottom:var(--edge);
  padding-bottom:10px;margin-bottom:clamp(20px,3vw,36px);
}
.ps-chapter__no{font-family:var(--font-mono);font-size:var(--fs-1);letter-spacing:.14em;color:var(--signal-600)}
.ps-chapter__title{font-size:var(--fs-4);font-weight:900;letter-spacing:-.02em}
.ps-chapter__note{margin-left:auto;font-family:var(--font-mono);font-size:var(--fs-1);color:var(--steel-300)}

/* ============ 05 SKIP LINK ============ */
.ps-skip{
  position:fixed;left:12px;top:-72px;z-index:200;
  background:var(--signal-600);color:var(--ink-950);
  padding:10px 18px;font-weight:700;font-size:var(--fs-2);letter-spacing:.04em;
  transition:top .2s var(--ease);
}
.ps-skip:focus{top:12px}

/* ============ 06 HEADER ============ */
.ps-masthead{
  position:sticky;top:0;z-index:80;
  background:var(--ink-950);
  border-bottom:2px solid var(--line-500);
}
.ps-progress{
  position:absolute;left:0;bottom:-2px;width:100%;height:2px;
  background:var(--signal-600);
  transform:scaleX(0);transform-origin:left center;
  will-change:transform;
}
.ps-cmdbar{position:relative}
.ps-cmdbar__inner{
  display:flex;align-items:center;gap:clamp(10px,1.8vw,26px);
  min-height:66px;padding-block:8px;
}
.ps-masthead[data-condensed] .ps-cmdbar__inner{min-height:54px;padding-block:4px}

.ps-brand{display:inline-flex;align-items:center;gap:10px;flex:0 0 auto}
.ps-brand__mark{
  display:grid;place-items:center;
  width:38px;height:38px;
  background:var(--signal-600);color:var(--ink-950);
  font-weight:900;font-size:var(--fs-2);letter-spacing:-.04em;
  border:var(--edge-dark);
}
.ps-brand__text{display:flex;flex-direction:column;line-height:1.15}
.ps-brand__name{font-size:var(--fs-4);font-weight:900;letter-spacing:-.02em}
.ps-brand__tag{font-family:var(--font-mono);font-size:var(--fs-1);letter-spacing:.06em;color:var(--steel-300)}

.ps-nav{flex:1 1 auto;min-width:0}
.ps-nav__list{display:flex;align-items:center;justify-content:flex-end;gap:2px}
.ps-nav__link{
  display:block;padding:10px 11px;
  font-size:.9rem;font-weight:500;letter-spacing:.06em;line-height:1;
  color:var(--steel-300);
  border-left:2px solid transparent;
  transition:color .2s var(--ease),background-color .2s var(--ease),border-color .2s var(--ease);
}
.ps-nav__link:hover,.ps-nav__link:focus-visible{color:var(--paper-050);background:var(--pitch-700)}
.ps-nav__link[aria-current="page"]{
  color:var(--paper-050);
  border-left-color:var(--signal-600);
  box-shadow:inset 0 -2px 0 0 var(--signal-600);
}

.ps-cmdbar__actions{display:flex;align-items:center;gap:12px;flex:0 0 auto;margin-left:auto}
.ps-status{display:inline-flex;align-items:center;gap:7px;font-family:var(--font-mono);font-size:var(--fs-1);color:var(--steel-300)}
.ps-status__dot{
  width:8px;height:8px;background:var(--signal-600);
  box-shadow:0 0 0 3px rgba(255,90,31,.18);
  animation:ps-pulse 2.4s var(--ease) infinite;
}
@keyframes ps-pulse{0%,100%{opacity:1}50%{opacity:.35}}

.ps-burger{
  display:none;align-items:center;gap:8px;
  padding:9px 12px;border:var(--edge);background:var(--pitch-700);
  font-size:var(--fs-2);font-weight:500;letter-spacing:.06em;
}
.ps-burger[aria-expanded="true"]{border-color:var(--signal-600);color:var(--signal-600)}
.ps-burger__bars{position:relative;width:16px;height:10px;display:block}
.ps-burger__bars::before,.ps-burger__bars::after{
  content:"";position:absolute;left:0;width:16px;height:2px;background:currentColor;
  transition:transform .24s var(--ease),top .24s var(--ease);
}
.ps-burger__bars::before{top:0}
.ps-burger__bars::after{top:8px}
.ps-burger[aria-expanded="true"] .ps-burger__bars::before{top:4px;transform:rotate(45deg)}
.ps-burger[aria-expanded="true"] .ps-burger__bars::after{top:4px;transform:rotate(-45deg)}

.ps-rail{background:var(--pitch-700);border-top:1px solid var(--line-500)}
.ps-rail__inner{
  display:flex;align-items:center;gap:14px;
  min-height:38px;
  font-family:var(--font-mono);font-size:var(--fs-1);color:var(--steel-300);
  overflow-x:auto;scrollbar-width:none;
}
.ps-rail__inner::-webkit-scrollbar{display:none}
.ps-rail__item{white-space:nowrap}
.ps-rail__item b{color:var(--paper-050);font-weight:500}
.ps-rail__sep{width:1px;height:14px;background:var(--line-500);flex:0 0 auto}
.ps-rail__link{
  margin-left:auto;white-space:nowrap;color:var(--amber-400);
  border-bottom:1px solid var(--amber-400);
}
.ps-masthead[data-condensed] .ps-rail{display:none}

/* ============ 07 BUTTONS ============ */
.ps-btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:11px 18px;
  border:var(--edge);background:transparent;color:var(--paper-050);
  font-size:var(--fs-2);font-weight:500;letter-spacing:.06em;line-height:1;
  transition:transform .2s var(--ease),border-color .2s var(--ease),background-color .2s var(--ease),color .2s var(--ease);
}
.ps-btn:hover,.ps-btn:focus-visible{border-color:var(--signal-600);transform:translateX(2px)}
.ps-btn--signal{background:var(--signal-600);border-color:var(--signal-600);color:var(--ink-950);font-weight:700}
.ps-btn--signal:hover,.ps-btn--signal:focus-visible{background:var(--amber-400);border-color:var(--amber-400)}
.ps-btn--ghost{border-color:var(--line-500)}

/* ============ 08 通用组件 ============ */
.ps-card{
  border:var(--edge);background:var(--pitch-700);
  padding:clamp(16px,2.2vw,26px);
  transition:transform .2s var(--ease),border-color .2s var(--ease),box-shadow .2s var(--ease);
}
.ps-card:hover,.ps-card:focus-within{border-color:var(--signal-600);transform:translateX(2px);box-shadow:var(--shadow-hard)}

.ps-board{
  background:var(--paper-050);color:var(--ink-950);
  border:var(--edge-dark);box-shadow:var(--shadow-hard);
  padding:clamp(16px,2.4vw,28px);
}
.ps-board .ps-tag{border-color:var(--ink-950);color:var(--ink-950)}

.ps-tag{
  display:inline-block;padding:3px 8px;
  font-family:var(--font-mono);font-size:var(--fs-1);letter-spacing:.08em;line-height:1.5;
  border:1px solid var(--line-500);color:var(--steel-300);
}
.ps-tag--signal{border-color:var(--signal-600);color:var(--signal-600)}

.ps-bar{height:10px;background:var(--pitch-700);border:1px solid var(--line-500);overflow:hidden}
.ps-bar__fill{display:block;height:100%;width:var(--w,50%);background:var(--amber-400)}

.ps-crumbs{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;
  font-family:var(--font-mono);font-size:var(--fs-1);letter-spacing:.04em;color:var(--steel-300);
}
.ps-crumbs li{display:inline-flex;align-items:center;gap:8px}
.ps-crumbs li+li::before{content:"/";color:var(--line-500)}
.ps-crumbs a{border-bottom:1px solid transparent}
.ps-crumbs a:hover,.ps-crumbs a:focus-visible{color:var(--paper-050);border-bottom-color:var(--signal-600)}
.ps-crumbs [aria-current="page"]{color:var(--paper-050)}

.ps-figure{margin:0;border:var(--edge);background:var(--pitch-700)}
.ps-figure__media{
  position:relative;overflow:hidden;aspect-ratio:var(--ratio,16/10);
  background-color:var(--pitch-700);
  background-image:
    repeating-linear-gradient(0deg,rgba(169,189,208,.10) 0 1px,transparent 1px 24px),
    repeating-linear-gradient(90deg,rgba(169,189,208,.10) 0 1px,transparent 1px 24px);
}
.ps-figure__media>img{width:100%;height:100%;object-fit:cover}
.ps-figure__cap{
  padding:8px 10px;border-top:1px solid var(--line-500);
  font-family:var(--font-mono);font-size:var(--fs-1);color:var(--muted-400);
}
.ps-figure--wide{--ratio:21/9}
.ps-figure--tall{--ratio:3/4}
.ps-figure--square{--ratio:1/1}

/* ============ 09 FOOTER ============ */
.ps-footer{
  background:var(--ink-950);
  border-top:2px solid var(--line-500);
  margin-top:clamp(40px,7vw,96px);
  padding-block:clamp(36px,6vw,72px) clamp(20px,3vw,32px);
}
.ps-footer__top{display:grid;grid-template-columns:1fr;gap:clamp(28px,4vw,48px)}
.ps-footer__brand{display:flex;flex-direction:column;align-items:flex-start;gap:16px}
.ps-footer__mark{
  font-size:var(--fs-5);font-weight:900;letter-spacing:-.02em;
  padding-left:14px;border-left:6px solid var(--signal-600);
}
.ps-footer__lede{max-width:30em;font-size:var(--fs-2);line-height:1.7;color:var(--steel-300)}
.ps-footer__cols{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}
.ps-footer__coltitle{
  font-family:var(--font-mono);font-size:var(--fs-1);letter-spacing:.14em;
  color:var(--signal-600);padding-bottom:8px;margin-bottom:10px;
  border-bottom:1px solid var(--line-500);
}
.ps-footer__list{display:flex;flex-direction:column;gap:8px}
.ps-footer__link{font-size:var(--fs-2);color:var(--paper-050);border-bottom:1px solid transparent;transition:border-color .2s var(--ease),color .2s var(--ease)}
.ps-footer__link:hover,.ps-footer__link:focus-visible{color:var(--amber-400);border-bottom-color:var(--amber-400)}
.ps-footer__meta{
  margin-top:clamp(28px,4vw,48px);padding-top:18px;
  border-top:2px solid var(--line-500);
  display:flex;flex-wrap:wrap;gap:10px 26px;
  font-family:var(--font-mono);font-size:var(--fs-1);color:var(--muted-400);line-height:1.7;
}
.ps-footer__legal{color:var(--steel-300)}
.ps-footer__contact{max-width:none}
.ps-footer__copy{max-width:none;margin-left:auto}

@media (min-width:760px){
  .ps-footer__cols{grid-template-columns:repeat(4,minmax(0,1fr))}
}
@media (min-width:960px){
  .ps-footer__top{grid-template-columns:minmax(0,4fr) minmax(0,8fr);align-items:start}
}

/* ============ 10 显现动效 ============ */
.ps-js [data-reveal]{
  opacity:0;transform:translateY(12px);
  transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease);
  will-change:opacity,transform;
}
.ps-js [data-reveal].is-in{opacity:1;transform:none}

/* ============ 11 响应式 ============ */
@media (max-width:1080px){
  .ps-status__text{display:none}
}
@media (max-width:960px){
  .ps-cmdbar__cta{display:none}
}
@media (max-width:899px){
  .ps-cmdbar__inner{min-height:58px}
  .ps-brand__tag{display:none}
  .ps-nav{
    position:absolute;left:0;right:0;top:100%;z-index:5;
    background:var(--pitch-900);
    border-bottom:2px solid var(--line-500);
    padding:10px var(--gutter) 18px;
  }
  .ps-nav__list{flex-direction:column;align-items:stretch;justify-content:flex-start;gap:0}
  .ps-nav__link{
    padding:15px 12px;font-size:var(--fs-3);
    border-left:2px solid transparent;
    border-bottom:1px solid var(--line-500);
  }
  .ps-js .ps-nav{
    opacity:0;visibility:hidden;transform:translateY(-10px);
    transition:opacity .24s var(--ease),transform .24s var(--ease),visibility .24s linear;
  }
  .ps-js .ps-nav[data-open]{opacity:1;visibility:visible;transform:none}
  .ps-burger{display:inline-flex}
  .ps-rail__link{margin-left:14px}
}
@media (max-width:520px){
  .ps-brand__mark{width:34px;height:34px}
  .ps-brand__name{font-size:var(--fs-3)}
  .ps-chapter__note{display:none}
}

/* ============ 12 动效降级 ============ */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .ps-js [data-reveal]{opacity:1;transform:none}
}