/* ==========================================================================
   VPNBL · base.css
   设计令牌(:root) / reset / 排版 / 按钮 / 头部导航 / 页脚 / 通用容器 / reveal
   所有颜色、圆角、阴影、字体只在本文件的 :root 里定义,组件一律引用变量。
   ========================================================================== */

:root{
  /* ---- 基底 · 氛围层 · 面板 三级层次 ---- */
  --bg:#E8F1F6;
  --bg-hero-top:#F3F9FC;
  --bg-hero-bottom:#DCE9F0;
  --bg-panel:#FFFFFF;
  --bg-panel-2:#D7E6EF;
  --bg-panel-3:#F1F7FB;
  --border:#C6DAE5;
  --border-soft:rgba(198,218,229,.62);
  --panel-glass:rgba(255,255,255,.74);
  --panel-glass-soft:rgba(255,255,255,.56);

  /* ---- 主色三档 ---- */
  --accent:#175E7D;
  --accent-lift:#1C6E90;
  --accent-dark:#0C3D52;
  --accent-wash:rgba(23,94,125,.07);
  --accent-edge:rgba(23,94,125,.20);
  --accent-halo:rgba(23,94,125,.10);
  --accent-clear:rgba(23,94,125,0);

  /* ---- 卡片底色(只作卡底,不做正文色) ---- */
  --card-ink:#1F5F7A;
  --card-ink-deep:#164A60;
  --card-violet:#6C63C8;
  --card-violet-deep:#544CA8;
  --card-cyan:#7FC4D8;
  --card-cyan-deep:#5FA6BE;
  --card-gold:#E0A32E;
  --card-gold-deep:#C2851A;

  /* ---- 文本 ---- */
  --text:#14212B;
  --text-muted:#566B78;
  --on-dark:#FFFFFF;
  --on-light:#0C3D52;

  /* ---- 语义色 ---- */
  --success:#1E8A5F;
  --success-wash:rgba(30,138,95,.09);
  --success-edge:rgba(30,138,95,.24);
  --success-halo:rgba(30,138,95,.18);
  --warn:#C6891A;
  --warn-wash:rgba(198,137,26,.10);
  --warn-edge:rgba(198,137,26,.24);
  --error:#C0443C;
  --error-wash:rgba(192,68,60,.10);
  --error-edge:rgba(192,68,60,.24);

  /* ---- 旗帜用色 ---- */
  --flag-red:#CE1126;
  --flag-blue:#3C3B6E;
  --flag-white:#FFFFFF;
  --flag-hk:#DE2910;
  --flag-jp:#BC002D;
  --flag-maple:#D80621;
  --flag-ring:rgba(12,61,82,.16);

  /* ---- 材质:内高光边 / 带色柔影 ---- */
  --ring-light:rgba(255,255,255,.62);
  --ring-inner:rgba(255,255,255,.46);
  --sheen-top:rgba(255,255,255,.18);
  --sheen-clear:rgba(255,255,255,0);
  --shadow-xs:0 6px 16px -12px rgba(23,94,125,.55);
  --shadow-panel:0 22px 44px -26px rgba(23,94,125,.36);
  --shadow-window:0 0 0 1px var(--ring-light),0 18px 34px -16px rgba(9,45,62,.45);
  --shadow-cta:0 14px 26px -12px rgba(23,94,125,.55);
  --shadow-cta-hover:0 20px 32px -14px rgba(23,94,125,.62);
  --shadow-badge:0 18px 32px -14px rgba(23,94,125,.50);
  --shadow-card-ink:0 20px 34px -22px rgba(31,95,122,.80);
  --shadow-card-violet:0 20px 34px -22px rgba(108,99,200,.80);
  --shadow-card-cyan:0 20px 34px -22px rgba(95,166,190,.80);
  --shadow-card-gold:0 20px 34px -22px rgba(194,133,26,.80);
  --shadow-card-hover:0 30px 50px -24px rgba(12,61,82,.55);
  --shadow-accent-ring:0 0 0 3px var(--accent-halo);

  /* ---- 圆角 ---- */
  --r-btn:8px;
  --r-win:10px;
  --r-card:12px;
  --r-pill:999px;

  /* ---- 几何 ---- */
  --header-h:68px;
  --wrap:1240px;
  --gutter:24px;
  --sec-y:76px;

  /* ---- 字体 ---- */
  --font-display:"Inter","Noto Sans SC","Noto Sans JP","Noto Sans KR",-apple-system,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-body:"Inter","Noto Sans SC","Noto Sans JP","Noto Sans KR",-apple-system,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;

  /* ---- 字号 ---- */
  --fs-h1:clamp(52px,5.4vw,64px);
  --fs-h2:clamp(26px,3vw,38px);
  --fs-h3:clamp(19px,1.8vw,23px);
  --fs-lead:18px;

  /* ---- 页脚深色区(全站唯一深色块) ---- */
  --footer-bg:#0C3D52;
  --footer-bg-deep:#092C3C;
}

/* ==========================================================================
   reset
   ========================================================================== */
*,*::before,*::after{box-sizing:border-box}
html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:calc(var(--header-h) + 16px);
}
html.nav-open{overflow:hidden}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  overflow-x:clip;
}
img,svg{max-width:100%}
img{height:auto}
a{color:inherit;text-decoration:none}
ul,ol{margin:0;padding:0;list-style:none}
p,h1,h2,h3,h4,h5,h6,figure,blockquote{margin:0}
button{font:inherit;color:inherit}
input,select,textarea{font:inherit}
table{border-collapse:collapse}
svg{display:block}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:4px}
::selection{background:var(--accent);color:var(--bg-panel)}

/* ==========================================================================
   排版
   ========================================================================== */
h1,h2,h3,h4{font-family:var(--font-display);font-weight:900;line-height:1.14;letter-spacing:-.02em}
h1{font-size:clamp(30px,3.6vw,44px)}
h2{font-size:var(--fs-h2)}
h3{font-size:var(--fs-h3)}
h4{font-size:17px;font-weight:800;letter-spacing:-.01em}
p{font-size:16px}
strong{font-weight:800}

.lead{font-size:var(--fs-lead);line-height:1.6;color:var(--text-muted)}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.no-break{white-space:nowrap}
.sr-only{
  position:absolute;width:1px;height:1px;padding:0;margin:-1px;
  overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0;
}
.svg-sprite{position:absolute;width:0;height:0;overflow:hidden}

/* 行内代码:超长订阅串/文件名必须能断,否则 375px 必破 */
code{
  font-family:var(--font-mono);
  font-size:.92em;
  overflow-wrap:anywhere;
  word-break:break-word;
  padding:2px 6px;
  border-radius:6px;
  background:var(--bg-panel-2);
  color:var(--accent-dark);
}
pre{
  max-width:100%;
  overflow-x:auto;
  -webkit-overflow-scrolling:touch;
  padding:16px 18px;
  border-radius:var(--r-card);
  background:var(--bg-panel-3);
  border:1px solid var(--border);
  font-size:13.5px;
  line-height:1.7;
}
pre code{padding:0;background:none;color:var(--text);overflow-wrap:normal;white-space:pre}
blockquote{
  margin:0;
  padding:14px 18px;
  border-left:3px solid var(--accent-edge);
  background:var(--bg-panel-3);
  border-radius:0 var(--r-btn) var(--r-btn) 0;
  color:var(--text-muted);
}

/* ==========================================================================
   布局容器
   ========================================================================== */
.wrap{
  max-width:var(--wrap);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
/* 只声明纵向内距,严禁 padding:Y 0 —— 与 .wrap 同元素时会把左右留白清零 */
.sec{padding-block:var(--sec-y)}
.sec--tight{padding-block:calc(var(--sec-y) * .6)}
.sec--tint{background:var(--bg-panel-3)}
.sec__head{max-width:760px;margin-inline:auto;text-align:center;margin-bottom:36px}
.sec__head h2{margin-bottom:12px}
.sec__head p{color:var(--text-muted);font-size:16.5px}

.stack{display:grid;gap:16px}
.row{display:flex;flex-wrap:wrap;align-items:center;gap:12px}

/* ==========================================================================
   按钮
   ========================================================================== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:9px;
  min-height:52px;padding:12px 26px;
  border:1px solid transparent;border-radius:var(--r-btn);
  font-size:16px;font-weight:700;letter-spacing:.004em;text-align:center;
  cursor:pointer;
  transition:transform .18s ease,box-shadow .18s ease,background-color .18s ease,color .18s ease,border-color .18s ease;
}
.btn--primary{
  color:var(--bg-panel);
  background:linear-gradient(180deg,var(--accent-lift),var(--accent));
  box-shadow:var(--shadow-cta);
}
.btn--primary:hover{transform:translateY(-2px);box-shadow:var(--shadow-cta-hover)}
.btn--ghost{
  color:var(--accent-dark);
  background:var(--bg-panel);
  border-color:var(--border);
  box-shadow:var(--shadow-xs);
}
.btn--ghost:hover{transform:translateY(-2px);border-color:var(--accent);color:var(--accent)}
.btn--light{
  color:var(--accent-dark);
  background:var(--bg-panel);
  border-color:var(--border-soft);
  box-shadow:var(--shadow-xs);
}
.btn--light:hover{transform:translateY(-2px);color:var(--accent)}
.btn--sm{min-height:42px;padding:9px 18px;font-size:14px}
.btn--block{width:100%}
.btn__arrow{width:16px;height:16px;flex:none;color:currentColor;transition:transform .18s ease}
.btn--primary:hover .btn__arrow{transform:translateX(3px)}
.btn-mini{
  display:inline-flex;align-items:center;justify-content:center;
  min-height:30px;padding:6px 13px;border-radius:var(--r-btn);
  font-size:11px;font-weight:700;color:var(--bg-panel);background:var(--accent);
  box-shadow:0 8px 14px -8px rgba(23,94,125,.7);
  flex:none;white-space:nowrap;
}
.btn-text{
  display:inline-flex;align-items:center;justify-content:center;
  min-height:30px;padding:6px 10px;
  font-size:11px;font-weight:600;color:var(--text-muted);
  flex:none;white-space:nowrap;
}

/* ==========================================================================
   头部导航(由 header.js 注入)
   ========================================================================== */
.site-header{
  position:sticky;top:0;z-index:60;
  background:var(--bg-hero-top);
  border-bottom:1px solid var(--border-soft);
}
.site-header__inner{
  position:relative;
  max-width:1320px;margin-inline:auto;
  padding-inline:28px;
  height:var(--header-h);
  display:flex;align-items:center;gap:6px;
}
.brand{display:flex;align-items:center;gap:9px;flex:none;font-family:var(--font-display);font-weight:800;font-size:18px;letter-spacing:-.015em;color:var(--text)}
.brand__mark{width:28px;height:28px;flex:none}
.brand__name{white-space:nowrap}

.nav{display:flex;align-items:center;margin-left:22px;min-width:0}
.nav__list{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px}
.nav__list>li{display:flex;align-items:center}
.nav__link{
  display:inline-flex;align-items:center;gap:5px;
  min-height:36px;padding:8px 13px;
  border-radius:var(--r-btn);
  font-size:14.5px;font-weight:600;color:var(--text-muted);
  cursor:pointer;
  transition:color .18s ease,background-color .18s ease;
}
.nav__link:hover{color:var(--text);background:var(--accent-wash)}
.nav__link.is-active{color:var(--accent);background:var(--accent-wash)}
.nav__link.is-active::after{content:"";width:5px;height:5px;border-radius:50%;background:var(--accent);flex:none}

details.more,details.lang{position:relative}
details>summary{list-style:none;cursor:pointer}
details>summary::-webkit-details-marker{display:none}
.chev{width:12px;height:12px;flex:none;color:currentColor;opacity:.68;transition:transform .18s ease}
details[open] .chev{transform:rotate(180deg)}
.more__panel,.lang__panel{
  position:absolute;top:calc(100% + 8px);left:0;z-index:70;
  min-width:196px;padding:8px;display:grid;gap:2px;
  background:var(--bg-panel);
  border:1px solid var(--border);
  border-radius:var(--r-card);
  box-shadow:var(--shadow-panel);
}
.lang__panel{left:auto;right:0;min-width:160px}
.more__panel a,.lang__panel a{
  display:flex;align-items:center;min-height:38px;padding:9px 12px;
  border-radius:var(--r-btn);
  font-size:14px;font-weight:500;color:var(--text-muted);
}
.more__panel a:hover,.lang__panel a:hover{background:var(--accent-wash);color:var(--accent)}
.lang__panel a[aria-current="true"]{color:var(--accent);font-weight:700;background:var(--accent-wash)}

.nav__right{margin-left:auto;display:flex;align-items:center;gap:10px;flex:none}
.lang__btn{
  display:inline-flex;align-items:center;justify-content:center;gap:6px;
  min-height:38px;padding:8px 12px;border-radius:var(--r-btn);
  font-size:14px;font-weight:600;color:var(--text-muted);
}
.lang__btn:hover{color:var(--text);background:var(--accent-wash)}
.lang__btn span{white-space:nowrap}
.lang__globe{width:16px;height:16px;flex:none}
.btn-login{
  display:inline-flex;align-items:center;justify-content:center;
  min-height:38px;padding:8px 18px;
  border:1px solid var(--accent);border-radius:var(--r-btn);
  font-size:14px;font-weight:700;color:var(--accent);background:var(--bg-panel);
  white-space:nowrap;
  transition:background-color .18s ease,color .18s ease;
}
.btn-login:hover{background:var(--accent);color:var(--bg-panel)}
.hamburger{
  display:none;align-items:center;justify-content:center;
  width:44px;height:44px;min-width:44px;min-height:44px;
  border:1px solid var(--border);border-radius:var(--r-btn);
  background:var(--bg-panel);color:var(--text);cursor:pointer;
}

/* 移动抽屉:实色背景、整行可点、独立于导航与工具区 */
.drawer{display:none}
.drawer__group{padding:10px 0;border-top:1px solid var(--border-soft)}
.drawer__group:first-child{border-top:0}
.drawer__label{
  display:block;padding:6px 20px 8px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;
  color:var(--text-muted);text-transform:uppercase;
}
.drawer a{
  display:flex;width:100%;align-items:center;
  min-height:48px;padding:12px 20px;
  font-size:15px;font-weight:600;color:var(--text);
  border-bottom:1px solid var(--border-soft);
}
.drawer a:hover{background:var(--accent-wash);color:var(--accent)}
.drawer a[aria-current="true"]{color:var(--accent);background:var(--accent-wash)}

/* ==========================================================================
   页脚(由 footer.js 注入)
   ========================================================================== */
.site-footer{background:var(--footer-bg);color:var(--on-dark)}
.footer__inner{
  max-width:var(--wrap);margin-inline:auto;
  padding:56px var(--gutter) 34px;
  display:grid;gap:34px;
  grid-template-columns:minmax(220px,1.3fr) repeat(3,minmax(150px,1fr));
}
.footer__logo{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-display);font-size:19px;font-weight:800;letter-spacing:-.015em}
.footer__logo img{width:30px;height:30px;flex:none}
.footer__tagline{margin-top:14px;font-size:14px;line-height:1.65;color:var(--on-dark);opacity:.74;max-width:340px}
.footer__title{
  font-family:var(--font-mono);font-size:11.5px;font-weight:700;
  letter-spacing:.12em;text-transform:uppercase;
  color:var(--on-dark);opacity:.6;margin-bottom:14px;
}
.footer__list{display:grid;gap:9px}
.footer__list a{font-size:14px;color:var(--on-dark);opacity:.8}
.footer__list a:hover{opacity:1;text-decoration:underline;text-underline-offset:3px}
.footer__legal{background:var(--footer-bg-deep)}
.footer__legal-inner{
  max-width:var(--wrap);margin-inline:auto;
  padding:18px var(--gutter);
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px 24px;
}
.footer__copy{font-size:13px;color:var(--on-dark);opacity:.7}
.footer__legal-links{display:flex;flex-wrap:wrap;align-items:center;gap:8px 20px}
.footer__legal-links a{display:inline-flex;align-items:center;min-height:32px;font-size:13px;color:var(--on-dark);opacity:.78}
.footer__legal-links a:hover{opacity:1;text-decoration:underline;text-underline-offset:3px}

/* ==========================================================================
   reveal:默认可见,只有视口外的元素由 JS 加 .pending
   ========================================================================== */
.reveal{transition:opacity .6s ease,transform .6s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}

/* ==========================================================================
   响应式
   ========================================================================== */
@media (max-width:1100px){
  .footer__inner{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (max-width:900px){
  .site-header__inner{padding-inline:16px;gap:8px}
  .nav{display:none}
  .nav__right{margin-left:auto}
  .hamburger{display:inline-flex}
  html.nav-open .drawer{
    display:block;
    position:absolute;top:var(--header-h);left:0;right:0;z-index:75;
    background:var(--bg-panel);
    border-bottom:1px solid var(--border);
    box-shadow:var(--shadow-panel);
    max-height:calc(100dvh - var(--header-h));
    overflow-y:auto;
    overscroll-behavior:contain;
  }
}
@media (max-width:768px){
  :root{--fs-h1:clamp(28px,8.6vw,38px);--sec-y:56px}
}
@media (max-width:640px){
  :root{--gutter:16px;--sec-y:48px}
  .no-break{white-space:normal}
  .footer__inner{grid-template-columns:minmax(0,1fr);gap:26px;padding-top:40px}
  .footer__legal-inner{flex-direction:column;align-items:flex-start}
  .btn{width:100%}
  .btn--sm{width:auto}
  pre{font-size:12.5px}
}

/* ==========================================================================
   动效偏好
   ========================================================================== */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms!important;
    animation-iteration-count:1!important;
    transition-duration:.001ms!important;
  }
  .reveal,.reveal.pending{opacity:1;transform:none}
  .btn--primary:hover,.btn--ghost:hover,.btn--light:hover{transform:none}
}

/* lh:local-harden:start */
:is(h1,h2,h3,h4){text-wrap:balance}
:is(p,li,dd,dt,figcaption,blockquote,td,th){text-wrap:pretty}
html[lang|="ko"] body{word-break:keep-all;overflow-wrap:break-word}
html[lang|="ja"] :is(h1,h2,h3,h4){word-break:auto-phrase}
.lh-tscroll{overflow-x:auto;max-width:100%;-webkit-overflow-scrolling:touch}
@media (max-width:640px){.lh-tscroll :is(th,td){min-width:5.5em}}
@supports (animation-timeline:scroll()){
  .float-cta{animation:lh-fab-in linear both;animation-timeline:scroll(root);animation-range:0 70vh}
}
@keyframes lh-fab-in{0%,45%{opacity:0;visibility:hidden}100%{opacity:1;visibility:visible}}
/* lh:local-harden:end */