/* =========================================================
   四季体育赛事 · 共享外壳样式表  /assets/site.css
   层级：tokens → reset → 排版 → 页头 → 页脚 → 通用组件 → 响应式
   ========================================================= */

/* ---------- 1 · 设计变量 ---------- */
:root{
  /* 深墨色体系 */
  --ink-950:#080C10;
  --ink-800:#111A21;
  --ink-700:#1B2730;
  /* 暖纸色体系 */
  --paper-50:#F5F0E6;
  --paper-300:#DED3C0;
  --paper-ink:#171310;
  /* 四季强调色 */
  --spring:#A9E63C;
  --summer:#37C7FF;
  --autumn:#FF9E3D;
  --winter:#D9E3EB;
  --coral:#FF6B5E;
  --slate:#93A5B2;
  /* 文字与线 */
  --text:#E8EDF1;
  --text-soft:#C6D1DA;
  --line:rgba(217,227,235,.14);
  --line-soft:rgba(217,227,235,.10);
  --line-strong:rgba(217,227,235,.26);
  /* 字体栈（全部本地回退，不加载远程字体） */
  --font-display:"Archivo Narrow","Oswald","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:system-ui,-apple-system,"Segoe UI","Noto Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
  --font-mono:ui-monospace,"JetBrains Mono","Roboto Mono",SFMono-Regular,Menlo,Consolas,monospace;
  /* 度量 */
  --shell:1240px;
  --gutter:clamp(16px,4vw,40px);
  --cut:12px;
  --ease:cubic-bezier(.22,.61,.36,1);
}

/* ---------- 2 · reset ---------- */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  background:var(--ink-950);
  color:var(--text);
  font-family:var(--font-body);
  font-size:1rem;
  font-weight:400;
  line-height:1.8;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,h4,h5,h6,p,figure,blockquote,dl,dd{margin:0}
h1,h2,h3,h4,h5,h6{font-weight:800;line-height:1.2;letter-spacing:-.01em}
ul,ol{margin:0;padding:0;list-style:none}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
img,picture,video,svg,canvas{display:block;max-width:100%;height:auto}
table{border-collapse:collapse;width:100%}
::selection{background:var(--summer);color:#04141C}
:focus-visible{outline:2px solid var(--summer);outline-offset:3px;border-radius:2px}
:focus:not(:focus-visible){outline:none}
.nav-locked{overflow:hidden}

/* ---------- 3 · 布局与容器 ---------- */
.shell{
  width:100%;
  max-width:var(--shell);
  margin-inline:auto;
  padding-inline:var(--gutter);
}
.section{
  position:relative;
  padding-block:clamp(48px,7vw,96px);
  background:var(--ink-950);
}
.section--ink{background:var(--ink-800)}
.section--paper{background:var(--paper-50);color:var(--paper-ink)}
.section--paper .lede,.section--paper .prose,.section--paper .prose p{color:#3B342C}
.section--paper .eyebrow,.section--paper .label{color:#6A6157}
.section--paper .display{color:var(--paper-ink)}
.section--paper .divider{background:var(--paper-300)}
.divider{height:1px;border:0;margin:0;background:var(--line)}

.grid{display:grid;gap:clamp(16px,2.2vw,24px);grid-template-columns:1fr}
.grid--2,.grid--3,.grid--4{grid-template-columns:1fr}
.grid--split{grid-template-columns:1fr;align-items:start}
@media (min-width:720px){
  .grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .grid--4{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (min-width:1024px){
  .grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
  .grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}
  .grid--split{grid-template-columns:minmax(0,1.4fr) minmax(0,1fr);gap:clamp(28px,4vw,56px)}
  .grid__panel{margin-top:72px}
}

/* ---------- 4 · 中文排版层级 ---------- */
.display{
  font-family:var(--font-display);
  font-weight:900;
  font-size:clamp(2.6rem,7vw,6.5rem);
  line-height:.95;
  letter-spacing:-.02em;
  color:#FFFFFF;
}
.lede{
  font-size:clamp(1.0625rem,1.4vw,1.25rem);
  line-height:1.75;
  color:var(--text-soft);
  max-width:58ch;
}
.prose{
  max-width:70ch;
  font-size:1rem;
  line-height:1.85;
  color:#D6DEE5;
}
.prose p + p{margin-top:1em}
.prose h2,.prose h3{margin-bottom:.5em;color:#FFFFFF}
.prose h2{font-size:clamp(1.4rem,2.4vw,1.9rem)}
.prose h3{font-size:clamp(1.15rem,1.8vw,1.35rem)}
.prose ul,.prose ol{margin:1em 0;padding-left:1.2em;list-style:disc}
.prose li + li{margin-top:.4em}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  font-size:.75rem;
  font-weight:700;
  letter-spacing:.18em;
  color:var(--winter);
  text-transform:uppercase;
}
.eyebrow::before{
  content:"";
  width:24px;
  height:3px;
  flex:0 0 auto;
  background:var(--accent,var(--summer));
}
.label{
  display:inline-block;
  font-family:var(--font-mono);
  font-weight:600;
  font-size:.75rem;
  letter-spacing:.16em;
  color:var(--slate);
}
.mono{
  font-family:var(--font-mono);
  font-weight:600;
  letter-spacing:.04em;
}

/* ---------- 5 · 按钮 ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:12px 22px;
  font-size:.875rem;
  font-weight:700;
  letter-spacing:.08em;
  line-height:1.2;
  border:1px solid transparent;
  border-radius:4px;
  clip-path:polygon(0 0,100% 0,100% calc(100% - 10px),calc(100% - 10px) 100%,0 100%);
  transition:transform .2s var(--ease),background-color .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.btn:hover{transform:translateY(-1px)}
.btn--primary{background:var(--spring);color:#0A1403}
.btn--primary:hover{background:#BEF65A}
.btn--ghost{border-color:var(--summer);color:var(--summer)}
.btn--ghost:hover{background:rgba(55,199,255,.12)}
.btn--paper{background:var(--paper-50);color:var(--paper-ink);border-color:var(--paper-300)}
.btn--paper:hover{background:#FFFFFF}
.btn--small{padding:9px 15px;font-size:.75rem;letter-spacing:.1em}

/* ---------- 6 · 跳转链接 ---------- */
.skip-link{
  position:absolute;
  left:16px;
  top:-72px;
  z-index:200;
  padding:10px 18px;
  background:var(--spring);
  color:#0A1403;
  font-size:.875rem;
  font-weight:700;
  border-radius:0 0 10px 10px;
  transition:top .22s var(--ease);
}
.skip-link:focus{top:0}

/* ---------- 7 · 页头 · 双层信息导航 ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:100;
  background:rgba(8,12,16,.94);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);
}
.topbar{
  overflow:hidden;
  max-height:80px;
  border-bottom:1px solid var(--line-soft);
  background:linear-gradient(90deg,
    rgba(169,230,60,.13) 0%,
    rgba(55,199,255,.13) 34%,
    rgba(255,158,61,.13) 68%,
    rgba(217,227,235,.13) 100%);
  transition:max-height .34s var(--ease),opacity .28s var(--ease);
}
.topbar__inner{
  display:flex;
  align-items:center;
  gap:clamp(12px,2vw,24px);
  min-height:42px;
  padding-block:8px;
  font-size:.75rem;
}
.topbar__brand{
  margin-right:auto;
  font-weight:600;
  letter-spacing:.08em;
  color:var(--winter);
}
.topbar__hint{
  letter-spacing:.14em;
  color:var(--slate);
}
.topbar__cta{
  flex:0 0 auto;
  padding-bottom:2px;
  font-weight:700;
  letter-spacing:.12em;
  color:var(--summer);
  border-bottom:1px solid transparent;
  transition:border-color .2s var(--ease),color .2s var(--ease);
}
.topbar__cta:hover{border-color:currentColor;color:#7BDCFF}

.navbar{position:relative}
.navbar__inner{
  display:flex;
  align-items:center;
  gap:clamp(12px,1.8vw,24px);
  min-height:74px;
  padding-block:10px;
  transition:min-height .3s var(--ease);
}
.brand{display:flex;align-items:center;gap:12px;flex:0 0 auto}
.brand__mark{
  width:34px;
  height:34px;
  flex:0 0 auto;
  background:linear-gradient(135deg,var(--spring) 0%,var(--spring) 22%,var(--summer) 38%,var(--autumn) 68%,var(--winter) 100%);
  clip-path:polygon(0 0,100% 0,100% 72%,72% 100%,0 100%);
}
.brand__text{display:flex;flex-direction:column;line-height:1.15}
.brand__name{font-size:1.0625rem;font-weight:800;letter-spacing:.02em;color:#FFFFFF}
.brand__sub{
  font-family:var(--font-mono);
  font-size:.6875rem;
  letter-spacing:.1em;
  color:var(--slate);
}

.mainnav{display:flex;align-items:center;gap:clamp(8px,1.6vw,22px);margin-left:auto}
.mainnav__title{display:none}
.mainnav__list{display:flex;align-items:center;gap:clamp(8px,1.6vw,22px)}
.mainnav__item{display:block}
.mainnav__link{
  position:relative;
  display:inline-block;
  padding:8px 2px;
  font-size:.9375rem;
  font-weight:500;
  letter-spacing:.02em;
  color:var(--text-soft);
  white-space:nowrap;
  transition:color .2s var(--ease);
}
.mainnav__link::after{
  content:"";
  position:absolute;
  left:0;
  right:100%;
  bottom:2px;
  height:2px;
  background:var(--spring);
  transition:right .26s var(--ease);
}
.mainnav__link:hover{color:#FFFFFF}
.mainnav__link:hover::after{right:0}
.mainnav__link[aria-current="page"]{color:var(--spring);font-weight:700}
.mainnav__link[aria-current="page"]::after{right:0;background:var(--spring)}
.mainnav__cta{display:none}

.navbar__actions{display:flex;align-items:center;gap:12px;flex:0 0 auto}
.season-chip{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:7px 13px;
  font-size:.75rem;
  letter-spacing:.1em;
  color:var(--winter);
  background:rgba(27,39,48,.66);
  border:1px solid var(--line-strong);
  border-radius:999px;
  white-space:nowrap;
}
.season-chip__dot{
  width:8px;
  height:8px;
  flex:0 0 auto;
  border-radius:50%;
  background:var(--spring);
  animation:pulse 2.4s infinite;
}
.season-chip__label{font-weight:700}
.season-chip__note{
  padding-left:8px;
  color:var(--slate);
  border-left:1px solid var(--line-strong);
}
@keyframes pulse{
  0%{box-shadow:0 0 0 0 rgba(169,230,60,.55)}
  70%{box-shadow:0 0 0 8px rgba(169,230,60,0)}
  100%{box-shadow:0 0 0 0 rgba(169,230,60,0)}
}

.navtoggle{
  display:none;
  align-items:center;
  gap:9px;
  padding:10px 13px;
  font-size:.75rem;
  font-weight:700;
  letter-spacing:.12em;
  color:var(--winter);
  border:1px solid var(--line-strong);
  border-radius:6px;
}
.navtoggle__bars,
.navtoggle__bars::before,
.navtoggle__bars::after{
  display:block;
  width:18px;
  height:2px;
  background:currentColor;
}
.navtoggle__bars{position:relative}
.navtoggle__bars::before,
.navtoggle__bars::after{content:"";position:absolute;left:0}
.navtoggle__bars::before{top:-6px}
.navtoggle__bars::after{top:6px}
.navtoggle[aria-expanded="true"]{color:var(--spring);border-color:var(--spring)}

.scroll-rail{
  position:relative;
  height:3px;
  background:var(--line-soft);
  overflow:hidden;
}
.scroll-rail__bar{
  display:block;
  width:0;
  height:100%;
  background:linear-gradient(90deg,var(--spring) 0%,var(--summer) 36%,var(--autumn) 68%,var(--winter) 100%);
  transition:width .12s linear;
}
.site-header[data-condensed] .topbar{max-height:0;opacity:0;border-bottom-color:transparent}
.site-header[data-condensed] .navbar__inner{min-height:62px}

/* ---------- 8 · 页脚 ---------- */
.site-footer{
  margin-top:clamp(56px,8vw,110px);
  background:var(--ink-800);
  border-top:1px solid var(--line-strong);
}
.footer__inner{
  display:grid;
  grid-template-columns:1fr;
  gap:clamp(28px,4vw,64px);
  padding-block:clamp(40px,6vw,72px);
}
.footer__lead{min-width:0}
.footer__brand{
  font-family:var(--font-display);
  font-size:clamp(1.5rem,3vw,2.2rem);
  font-weight:900;
  letter-spacing:-.01em;
  line-height:1.1;
  color:#FFFFFF;
}
.footer__line{
  margin-top:12px;
  max-width:34ch;
  font-size:.9375rem;
  line-height:1.8;
  color:var(--slate);
}
.footer__seasons{display:flex;flex-wrap:wrap;gap:8px;margin-top:22px}
.season-tag{
  display:inline-flex;
  align-items:center;
  padding:4px 11px;
  font-size:.75rem;
  letter-spacing:.12em;
  border:1px solid currentColor;
  border-radius:999px;
  white-space:nowrap;
}
.season-tag--spring{color:var(--spring);border-color:rgba(169,230,60,.45);background:rgba(169,230,60,.08)}
.season-tag--summer{color:var(--summer);border-color:rgba(55,199,255,.45);background:rgba(55,199,255,.08)}
.season-tag--autumn{color:var(--autumn);border-color:rgba(255,158,61,.45);background:rgba(255,158,61,.08)}
.season-tag--winter{color:var(--winter);border-color:rgba(217,227,235,.4);background:rgba(217,227,235,.07)}

.footer__cols{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:clamp(20px,3vw,36px);
}
.footer-col__title{
  margin-bottom:12px;
  padding-bottom:8px;
  font-size:.75rem;
  font-weight:700;
  letter-spacing:.18em;
  color:var(--winter);
  border-bottom:1px solid var(--line);
}
.footer-col__list{display:flex;flex-direction:column;gap:9px}
.footer-col__link{
  font-size:.9375rem;
  line-height:1.6;
  color:var(--text-soft);
  transition:color .2s var(--ease);
}
.footer-col__link:hover{color:var(--summer)}
.footer-col__link[aria-current="page"]{color:var(--spring);font-weight:700}

.footer__contact{
  display:grid;
  grid-template-columns:1fr;
  gap:14px 32px;
  padding-block:26px;
  border-top:1px solid var(--line);
}
.contact-line{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:10px;
  font-size:.875rem;
}
.contact-line__key{
  flex:0 0 auto;
  font-size:.75rem;
  letter-spacing:.12em;
  color:var(--slate);
}
.contact-line__val{
  font-family:var(--font-mono);
  color:var(--winter);
  word-break:break-word;
}
.footer__note{
  font-size:.8125rem;
  line-height:1.75;
  color:var(--slate);
  max-width:78ch;
}
.footer__legal{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px 24px;
  padding-block:20px;
  font-size:.75rem;
  letter-spacing:.06em;
  color:var(--slate);
  border-top:1px solid var(--line);
}
.footer__copy{color:var(--slate)}
.footer__icp{font-family:var(--font-mono);color:var(--winter)}

@media (min-width:720px){
  .footer__contact{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (min-width:1024px){
  .footer__inner{grid-template-columns:minmax(240px,1fr) 2.4fr}
  .footer__cols{grid-template-columns:repeat(4,minmax(0,1fr))}
  .footer__contact{grid-template-columns:repeat(3,minmax(0,1fr))}
  .contact-line--wide{grid-column:1 / -1}
  .footer__note{grid-column:1 / -1}
}

/* ---------- 9 · 面包屑 ---------- */
.breadcrumbs{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  padding-block:14px;
  font-size:.75rem;
  letter-spacing:.1em;
  color:var(--slate);
}
.breadcrumbs__item{display:inline-flex;align-items:center;gap:8px}
.breadcrumbs__item + .breadcrumbs__item::before{content:"/";color:rgba(217,227,235,.35)}
.breadcrumbs__link{color:var(--winter);transition:color .2s var(--ease)}
.breadcrumbs__link:hover{color:var(--summer)}

/* ---------- 10 · 卡片 / 数据 / 标签 ---------- */
.card{
  --accent:var(--summer);
  position:relative;
  padding:clamp(18px,2.4vw,28px);
  background:var(--ink-700);
  border:1px solid var(--line);
  clip-path:polygon(0 0,100% 0,100% calc(100% - var(--cut)),calc(100% - var(--cut)) 100%,0 100%);
  transition:transform .25s var(--ease),border-color .25s var(--ease);
}
.card::before{
  content:"";
  position:absolute;
  left:clamp(18px,2.4vw,28px);
  top:0;
  width:24px;
  height:3px;
  background:var(--accent);
}
.card::after{
  content:"";
  position:absolute;
  left:0;
  bottom:0;
  width:0;
  height:2px;
  background:var(--accent);
  transition:width .3s var(--ease);
}
.card:hover{transform:translateY(-3px);border-color:rgba(55,199,255,.42)}
.card:hover::after{width:100%}
.card--spring{--accent:var(--spring)}
.card--summer{--accent:var(--summer)}
.card--autumn{--accent:var(--autumn)}
.card--winter{--accent:var(--winter)}
.card--coral{--accent:var(--coral)}

.data-panel{
  padding:clamp(16px,2vw,24px);
  background:rgba(27,39,48,.72);
  border:1px solid var(--line);
}
.data-row{
  display:flex;
  align-items:baseline;
  justify-content:space-between;
  gap:16px;
  padding:10px 0;
  border-bottom:1px dashed var(--line);
}
.data-row:last-child{border-bottom:0}
.data-row__key{font-size:.8125rem;letter-spacing:.08em;color:var(--slate)}
.data-row__val{font-family:var(--font-mono);font-weight:600;letter-spacing:.04em;color:var(--winter)}

.stat{display:flex;flex-direction:column;gap:4px}
.stat__value{
  font-family:var(--font-mono);
  font-weight:700;
  font-size:clamp(1.9rem,3.4vw,2.6rem);
  line-height:1;
  letter-spacing:.04em;
  color:var(--accent,var(--summer));
}
.stat__label{font-size:.8125rem;letter-spacing:.1em;color:var(--slate)}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 10px;
  font-size:.75rem;
  letter-spacing:.1em;
  border:1px solid currentColor;
  border-radius:999px;
}
.tag--spring{color:var(--spring);background:rgba(169,230,60,.08)}
.tag--summer{color:var(--summer);background:rgba(55,199,255,.08)}
.tag--autumn{color:var(--autumn);background:rgba(255,158,61,.08)}
.tag--winter{color:var(--winter);background:rgba(217,227,235,.07)}
.tag--coral{color:var(--coral);background:rgba(255,107,94,.1)}

/* ---------- 11 · 赛季时间轴 ---------- */
.timeline{position:relative;padding-left:30px}
.timeline::before{
  content:"";
  position:absolute;
  left:6px;
  top:8px;
  bottom:8px;
  width:2px;
  background:linear-gradient(180deg,var(--spring),var(--summer) 34%,var(--autumn) 68%,var(--winter));
  opacity:.7;
}
.timeline__item{
  --accent:var(--winter);
  position:relative;
  padding-bottom:28px;
}
.timeline__item::before{
  content:"";
  position:absolute;
  left:-30px;
  top:8px;
  width:14px;
  height:14px;
  border-radius:50%;
  background:var(--ink-950);
  border:2px solid var(--accent);
}
.timeline__item--spring{--accent:var(--spring)}
.timeline__item--summer{--accent:var(--summer)}
.timeline__item--autumn{--accent:var(--autumn)}
.timeline__item--winter{--accent:var(--winter)}
.timeline__date{
  display:block;
  font-family:var(--font-mono);
  font-size:.75rem;
  letter-spacing:.14em;
  color:var(--accent,var(--winter));
}

/* ---------- 12 · 图片容器（页面阶段放置占位图） ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  aspect-ratio:4 / 3;
  background:linear-gradient(160deg,var(--ink-700),var(--ink-800));
  clip-path:polygon(0 0,100% 0,100% calc(100% - var(--cut)),calc(100% - var(--cut)) 100%,0 100%);
}
.media-frame img{
  width:100%;
  height:100%;
  object-fit:cover;
  filter:saturate(.95) contrast(1.05);
}
.media-frame--wide{aspect-ratio:16 / 9}
.media-frame--tall{aspect-ratio:3 / 4}
.media-frame--square{aspect-ratio:1 / 1}
.media-frame__overlay{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  padding:16px;
  font-family:var(--font-mono);
  font-size:.75rem;
  letter-spacing:.06em;
  color:var(--winter);
  background:linear-gradient(180deg,rgba(8,12,16,0) 0%,rgba(8,12,16,.88) 100%);
}
.media-frame__caption{
  margin-top:10px;
  font-size:.8125rem;
  line-height:1.7;
  color:var(--slate);
}

/* ---------- 13 · 折叠内容组 ---------- */
.accordion{border-top:1px solid var(--line)}
.accordion__item{border-bottom:1px solid var(--line)}
.accordion__trigger{
  display:flex;
  align-items:center;
  gap:14px;
  width:100%;
  padding:18px 0;
  font-size:1.0625rem;
  font-weight:600;
  letter-spacing:.01em;
  text-align:left;
  color:var(--text);
  transition:color .2s var(--ease);
}
.accordion__trigger:hover{color:var(--summer)}
.accordion__trigger::after{
  content:"";
  margin-left:auto;
  width:10px;
  height:10px;
  flex:0 0 auto;
  border-right:2px solid var(--summer);
  border-bottom:2px solid var(--summer);
  transform:rotate(45deg);
  transition:transform .3s var(--ease);
}
.accordion__item[data-open] .accordion__trigger{color:var(--spring)}
.accordion__item[data-open] .accordion__trigger::after{transform:rotate(-135deg)}
.accordion__panel{
  height:0;
  overflow:hidden;
  opacity:0;
  transition:height .3s var(--ease),opacity .3s var(--ease);
}
.accordion__item[data-open] .accordion__panel{height:auto;opacity:1}
.accordion__body{
  padding-bottom:20px;
  max-width:72ch;
  font-size:.9375rem;
  line-height:1.85;
  color:var(--slate);
}

/* ---------- 14 · 分步引导 ---------- */
.steps{display:grid;gap:clamp(18px,2.4vw,28px)}
.steps__tabs{display:flex;flex-wrap:wrap;gap:10px}
.steps__tab{
  padding:10px 16px;
  font-size:.8125rem;
  font-weight:600;
  letter-spacing:.08em;
  color:var(--text-soft);
  border:1px solid var(--line-strong);
  border-radius:999px;
  transition:color .2s var(--ease),background-color .2s var(--ease),border-color .2s var(--ease);
}
.steps__tab:hover{color:#FFFFFF;border-color:var(--summer)}
.steps__tab[aria-selected="true"]{
  background:var(--summer);
  border-color:var(--summer);
  color:#04141C;
}
.steps__panel[hidden]{display:none}
.steps__body{
  padding:clamp(18px,2.4vw,28px);
  background:var(--ink-700);
  border:1px solid var(--line);
  clip-path:polygon(0 0,100% 0,100% calc(100% - var(--cut)),calc(100% - var(--cut)) 100%,0 100%);
}

/* ---------- 15 · 前端筛选 ---------- */
.filterbar{display:flex;flex-wrap:wrap;gap:8px}
.filterbar__btn{
  padding:8px 14px;
  font-size:.8125rem;
  font-weight:600;
  letter-spacing:.08em;
  color:var(--text-soft);
  border:1px solid var(--line-strong);
  border-radius:4px;
  transition:color .2s var(--ease),border-color .2s var(--ease),background-color .2s var(--ease);
}
.filterbar__btn:hover{color:#FFFFFF;border-color:var(--summer)}
.filterbar__btn[aria-pressed="true"]{
  color:var(--spring);
  border-color:var(--spring);
  background:rgba(169,230,60,.1);
}
[data-filter-item][hidden]{display:none}

/* ---------- 16 · 显现动效 ---------- */
.reveal{
  opacity:0;
  transform:translateY(16px);
  transition:opacity .5s var(--ease),transform .5s var(--ease);
}
.reveal.is-visible{opacity:1;transform:none}

/* ---------- 17 · 响应式 · 移动导航 ---------- */
@media (max-width:1023px){
  .navtoggle{display:inline-flex}
  .topbar__hint{display:none}
  .navbar__cta{display:none}
  .season-chip__note{display:none}
  .mainnav{
    position:absolute;
    top:100%;
    left:0;
    right:0;
    display:block;
    margin-left:0;
    padding:16px var(--gutter) 28px;
    background:var(--ink-800);
    border-top:1px solid var(--line);
    border-bottom:1px solid var(--line);
    max-height:calc(100vh - 118px);
    max-height:calc(100dvh - 118px);
    overflow-y:auto;
    opacity:0;
    visibility:hidden;
    transform:translateY(-10px);
    transition:opacity .28s var(--ease),transform .28s var(--ease),visibility .28s var(--ease);
  }
  .mainnav[data-open]{opacity:1;visibility:visible;transform:translateY(0)}
  .mainnav__title{
    display:block;
    margin-bottom:10px;
    font-size:.6875rem;
    font-weight:700;
    letter-spacing:.22em;
    color:var(--slate);
  }
  .mainnav__list{flex-direction:column;align-items:stretch;gap:0}
  .mainnav__item{border-bottom:1px solid var(--line-soft)}
  .mainnav__link{display:block;padding:15px 2px;font-size:1.0625rem;font-weight:600}
  .mainnav__link::after{display:none}
  .mainnav__link[aria-current="page"]::before{
    content:"";
    display:inline-block;
    width:9px;
    height:9px;
    margin-right:10px;
    background:var(--spring);
    clip-path:polygon(0 0,100% 50%,0 100%);
  }
  .mainnav__cta{display:inline-flex;width:100%;margin-top:18px}
}

@media (min-width:1024px){
  .mainnav__title{display:none}
}

/* ---------- 18 · 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;
  }
  .reveal{opacity:1;transform:none}
  .card:hover{transform:none}
  .btn:hover{transform:none}
}