/* 钔牌化学式查询库 — Apple 设计语言 */

:root{
  /* Apple 系统色（浅色） */
  --blue:#007AFF;
  --green:#34C759;
  --orange:#FF9500;
  --red:#FF3B30;
  --yellow:#FFCC00;

  /* 背景层级 */
  --bg:#F2F2F7;            /* systemGroupedBackground */
  --surface:#FFFFFF;       /* secondarySystemGroupedBackground */
  --surface-2:#F2F2F7;
  --fill:rgba(118,118,128,.12);
  --fill-2:rgba(118,118,128,.08);
  --pill:#FFFFFF;
  --pill-shadow:0 3px 8px rgba(0,0,0,.12), 0 1px 1px rgba(0,0,0,.04);

  /* 文字层级 */
  --label:#000000;
  --label-2:rgba(60,60,67,.6);
  --label-3:rgba(60,60,67,.3);
  --separator:rgba(60,60,67,.18);

  --dock:rgba(242,242,247,.72);

  /* 强调色：跟着用户选的版本走，两款各有各的主场。
     --accent 用于填充块，--accent-text 用于文字（浅色下要压深才够对比） */
  --accent:#007AFF;
  --accent-text:#007AFF;
  --on-accent:#FFFFFF;

  /* 圆角与缓动 */
  --r-card:18px;
  --r-ctrl:12px;
  --ease:cubic-bezier(.32,.72,0,1);

  --pad:clamp(16px,5vw,22px);
}

@media (prefers-color-scheme: dark){
  :root{
    --blue:#0A84FF;
    --green:#30D158;
    --orange:#FF9F0A;
    --red:#FF453A;
    --yellow:#FFD60A;

    --bg:#000000;
    --surface:#1C1C1E;
    --surface-2:#2C2C2E;
    --fill:rgba(118,118,128,.24);
    --fill-2:rgba(118,118,128,.16);
    --pill:#636366;
    --pill-shadow:0 3px 8px rgba(0,0,0,.5);

    --label:#FFFFFF;
    --label-2:rgba(235,235,245,.6);
    --label-3:rgba(235,235,245,.3);
    --separator:rgba(84,84,88,.65);

    --dock:rgba(0,0,0,.72);

    --accent:#0A84FF;
    --accent-text:#0A84FF;
  }
}

/* 经典款＝黑金，星空款＝蓝。骨架保持中性，只有强调色换。 */
body[data-ed="classic"]{
  --accent:#FF9500;          /* systemOrange */
  --accent-text:#9A5B00;     /* 白底上的金棕，保证可读 */
  --on-accent:#FFFFFF;
}
body[data-ed="star"]{
  --accent:#007AFF;
  --accent-text:#0062CC;     /* 比 systemBlue 压深一档，白底上才够对比 */
  --on-accent:#FFFFFF;
}
@media (prefers-color-scheme: dark){
  body[data-ed="classic"]{
    --accent:#FF9F0A;
    --accent-text:#FFD60A;   /* 黑底上就用亮金 */
    --on-accent:#3A2600;
  }
  body[data-ed="star"]{
    --accent:#0A84FF;
    --accent-text:#0A84FF;
  }
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0;
  background:var(--bg);
  color:var(--label);
  font:17px/1.47 -apple-system,BlinkMacSystemFont,"SF Pro Text","SF Pro Display",
       "Helvetica Neue","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}
h1,h2,h3,p{margin:0}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer;-webkit-tap-highlight-color:transparent}

.wrap{width:min(720px,100%); margin-inline:auto; padding-inline:var(--pad)}
.sec{margin-bottom:clamp(22px,5vw,34px)}

/* ---------- Hero ---------- */
.hero{padding:clamp(44px,10vw,86px) 0 clamp(26px,6vw,40px); text-align:center}
.tile{
  display:inline-grid; align-content:center; gap:1px;
  width:56px; height:62px; border-radius:14px; padding-left:10px;
  text-align:left; background:var(--surface);
  box-shadow:0 1px 3px rgba(0,0,0,.1), 0 8px 24px -12px rgba(0,0,0,.3);
  margin-bottom:clamp(18px,4vw,26px);
}
.tile-z{font-style:normal; font-size:10px; color:var(--label-3); letter-spacing:.2px}
/* 注：凡是 color 取自 --accent-text 的，都不要加 transition。
   自定义属性本身不可动画，过渡会卡在上一个版本的颜色上。 */
.tile-sym{
  font-size:25px; font-weight:600; color:var(--accent-text); line-height:1;
  letter-spacing:-.6px;
}
.tile-cn{font-style:normal; font-size:11px; color:var(--label-3)}

.hero h1{
  font-size:clamp(32px,7.6vw,52px); font-weight:700; line-height:1.08;
  letter-spacing:-.032em;
}
.hero .sub{
  margin-top:clamp(12px,3vw,18px);
  font-size:clamp(17px,3.6vw,21px); line-height:1.42; color:var(--label-2);
  letter-spacing:-.01em;
}

/* ---------- Segmented Control ---------- */
.seg-wrap{text-align:center}
.seg{
  position:relative; display:inline-grid; grid-auto-flow:column;
  grid-auto-columns:1fr; gap:0;
  padding:2px; border-radius:10px; background:var(--fill);
  width:min(340px,100%);
}
.seg-pill{
  position:absolute; top:2px; bottom:2px; left:2px;
  width:calc(50% - 2px); border-radius:8px;
  background:var(--pill); box-shadow:var(--pill-shadow);
  transition:transform .32s var(--ease);
}
.seg.on-star .seg-pill{transform:translateX(100%)}
.ed{
  position:relative; z-index:1; padding:7px 4px;
  font-size:15px; font-weight:500; color:var(--label-2);
  letter-spacing:-.01em;
}
.ed[aria-checked="true"]{font-weight:600; color:var(--accent-text)}
.seg .ed:focus-visible{outline:2px solid var(--accent); outline-offset:3px; border-radius:8px}
.seg-note{
  margin-top:12px; font-size:13px; color:var(--label-2); letter-spacing:-.005em;
}
.seg-note b{font-weight:600; color:var(--label)}

/* ---------- 搜索：吸顶毛玻璃 ---------- */
/* 吸顶前完全透明（和 iOS 大标题导航栏一致）；
   贴顶后才上毛玻璃——顺带避开 backdrop-filter 常驻时的合成层重绘问题 */
.searchdock{
  position:sticky; top:0; z-index:20;
  padding:10px 0 12px; margin-bottom:clamp(14px,3vw,20px);
  background:transparent;
  border-bottom:.5px solid transparent;
  transition:background .25s, border-color .25s;
}
.searchdock.stuck{
  background:var(--dock);
  -webkit-backdrop-filter:saturate(180%) blur(20px);
  backdrop-filter:saturate(180%) blur(20px);
  border-bottom-color:var(--separator);
}
.searchbar{position:relative; display:flex; align-items:center}
.mag{
  position:absolute; left:12px; width:16px; height:16px;
  fill:var(--label-3); pointer-events:none;
}
#q{
  width:100%; padding:11px 38px 11px 36px;
  font-size:17px; color:var(--label); letter-spacing:-.01em;
  background:var(--fill); border:0; border-radius:10px;
  -webkit-appearance:none; appearance:none;
  transition:box-shadow .2s;
}
#q::placeholder{color:var(--label-3)}
#q::-webkit-search-cancel-button{display:none}
#q:focus{outline:0; box-shadow:0 0 0 4px color-mix(in srgb,var(--accent) 25%,transparent)}
.clear{
  position:absolute; right:9px; width:22px; height:22px;
  display:grid; place-content:center; border-radius:50%;
}
.clear svg{width:16px; height:16px; fill:var(--label-3)}
.clear:hover svg{fill:var(--label-2)}

.chips{display:flex; flex-wrap:wrap; gap:8px; justify-content:center}
.chip{
  padding:6px 14px; border-radius:999px; font-size:15px; color:var(--accent-text);
  background:var(--fill-2); letter-spacing:-.01em;
  transition:background .18s, transform .18s var(--ease);
}
.chip:hover{background:var(--fill)}
.chip:active{transform:scale(.96)}

/* ---------- 分组卡（iOS inset grouped） ---------- */
.card,.group{
  background:var(--surface); border-radius:var(--r-card);
  box-shadow:0 1px 2px rgba(0,0,0,.04);
  overflow:hidden;
}
.card{animation:pop .38s var(--ease)}
@keyframes pop{from{opacity:0; transform:translateY(8px) scale(.985)}}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation-duration:.01ms !important; animation-iteration-count:1 !important; transition-duration:.01ms !important}
}

.card.empty{
  text-align:center; color:var(--label-3); font-size:15px;
  padding:clamp(34px,9vw,54px) var(--pad); box-shadow:none;
  background:var(--fill-2);
}

/* 卡内每一段，用发丝线分隔（左侧内缩，iOS 惯例） */
.row{padding:clamp(16px,4vw,20px)}
.row + .row{border-top:.5px solid var(--separator)}

/* 结论 */
.verdict{display:flex; align-items:flex-start; gap:12px}
.dot{
  flex:none; width:22px; height:22px; border-radius:50%; margin-top:1px;
  display:grid; place-content:center;
  font-size:13px; font-weight:700; color:#fff; line-height:1;
}
.verdict-txt strong{
  display:block; font-size:clamp(19px,4.4vw,22px); font-weight:600;
  line-height:1.28; letter-spacing:-.021em;
}
.verdict-txt p{margin-top:6px; font-size:15px; line-height:1.45; color:var(--label-2); letter-spacing:-.01em}

.t-ok .dot{background:var(--green)}
.t-ok .dot::after{content:"✓"}
.t-warn .dot{background:var(--orange)}
.t-warn .dot::after{content:"!"}
.t-miss .dot{background:var(--red)}
.t-miss .dot::after{content:"✕"; font-size:11px}

/* 化学式 */
.formula{display:flex; align-items:baseline; gap:12px; flex-wrap:wrap}
.formula .fx{
  font-size:clamp(30px,7.6vw,42px); font-weight:600; line-height:1.1;
  letter-spacing:-.028em; overflow-wrap:anywhere;
  font-family:-apple-system,BlinkMacSystemFont,"SF Pro Display","Helvetica Neue",sans-serif;
}
.formula .fname{font-size:17px; color:var(--label-2); letter-spacing:-.01em}
sub{font-size:.55em; vertical-align:baseline; position:relative; bottom:-.2em; font-weight:600}
.dotsep{margin-inline:.26em; color:var(--label-2)}

.meta{display:flex; flex-wrap:wrap; gap:6px; margin-top:14px}
.tag{
  padding:3px 10px; border-radius:999px; font-size:12px; font-weight:500;
  color:var(--label-2); background:var(--fill-2); letter-spacing:0;
}

/* 元素牌 */
.els-h,.sugg-h{
  font-size:13px; color:var(--label-2); margin-bottom:11px;
  letter-spacing:-.005em;
}
.els-row{display:flex; flex-wrap:wrap; gap:8px}
.pcard{
  display:grid; gap:1px; padding:8px 11px 7px; min-width:58px;
  border-radius:var(--r-ctrl); background:var(--fill-2);
  transition:transform .18s var(--ease);
}
.pcard .z{font-style:normal; font-size:10px; line-height:1.2; color:var(--label-3)}
.pcard .sym{font-size:19px; font-weight:600; line-height:1.1; letter-spacing:-.02em}
.pcard .cn{font-style:normal; font-size:11px; line-height:1.3; color:var(--label-2)}
.pcard:hover{transform:translateY(-1px)}

.pcard.has{background:color-mix(in srgb,var(--green) 16%,transparent)}
.pcard.has .sym{color:var(--green)}
.pcard.has .z,.pcard.has .cn{color:color-mix(in srgb,var(--green) 78%,var(--label-2))}

.pcard.no{
  background:color-mix(in srgb,var(--red) 11%,transparent);
  box-shadow:inset 0 0 0 1px color-mix(in srgb,var(--red) 40%,transparent);
}
.pcard.no .sym{color:var(--red)}
.pcard.no .z,.pcard.no .cn{color:color-mix(in srgb,var(--red) 72%,var(--label-2))}

/* 切换版本：Apple 填充按钮 */
.switch{display:flex; align-items:center; justify-content:space-between; gap:14px; flex-wrap:wrap}
.switch p{font-size:15px; line-height:1.45; color:var(--label-2); letter-spacing:-.01em; flex:1 1 200px}
/* 按钮用「目标版本」的颜色，点之前就知道要去哪一款 */
.switch button{
  flex:none; padding:10px 18px; border-radius:var(--r-ctrl);
  font-size:15px; font-weight:600; letter-spacing:-.01em;
  color:#fff; background:var(--blue);
  transition:transform .18s var(--ease), filter .18s;
}
.switch button:hover{filter:brightness(1.06)}
.switch button:active{transform:scale(.97)}
.switch.to-classic button{background:var(--orange); color:#3A2600}

.note{font-size:13px; line-height:1.5; color:var(--label-2); letter-spacing:-.005em}

.sugg-row{display:flex; flex-wrap:wrap; gap:8px}
.sugg-row button{
  padding:7px 13px; border-radius:var(--r-ctrl); font-size:15px;
  color:var(--label); background:var(--fill-2); letter-spacing:-.01em;
  transition:background .18s, transform .18s var(--ease);
}
.sugg-row button:hover{background:var(--fill)}
.sugg-row button:active{transform:scale(.97)}
.sugg-row small{color:var(--label-2); margin-left:6px; font-size:13px}

/* ---------- 浏览 ---------- */
.group summary{
  padding:15px clamp(16px,4vw,20px); cursor:pointer; list-style:none;
  display:flex; align-items:center; gap:10px;
  font-size:17px; letter-spacing:-.01em;
}
.group summary::-webkit-details-marker{display:none}
.group summary::after{
  content:""; flex:none; width:8px; height:8px; margin-left:2px;
  border-right:2px solid var(--label-3); border-bottom:2px solid var(--label-3);
  transform:rotate(45deg); transition:transform .3s var(--ease);
}
.group[open] summary::after{transform:rotate(-135deg)}
.cnt{font-style:normal; font-size:15px; color:var(--label-2); margin-left:auto}
.browse-body{padding:0 clamp(16px,4vw,20px) 18px; border-top:.5px solid var(--separator)}
.tabs{display:flex; gap:2px; padding:2px; margin:14px 0; border-radius:9px; background:var(--fill)}
.tab{
  flex:1; padding:6px 4px; border-radius:7px; font-size:14px; font-weight:500;
  color:var(--label); letter-spacing:-.01em; transition:background .2s, font-weight .2s;
}
.tab.is-on{background:var(--pill); box-shadow:var(--pill-shadow); font-weight:600}
.list{max-height:420px; overflow-y:auto; margin-inline:calc(-1 * clamp(16px,4vw,20px))}
.li{
  display:flex; align-items:baseline; gap:10px; width:100%; text-align:left;
  padding:11px clamp(16px,4vw,20px); font-size:16px; letter-spacing:-.01em;
  transition:background .15s;
}
.li + .li{box-shadow:inset 0 .5px 0 var(--separator)}
.li:hover{background:var(--fill-2)}
.li:active{background:var(--fill)}
.li b{font-weight:600; white-space:nowrap}
.li span{color:var(--label-2); font-size:14px; overflow:hidden; text-overflow:ellipsis; white-space:nowrap}
.li em{
  font-style:normal; font-size:11px; font-weight:500; margin-left:auto; flex:none;
  color:var(--accent-text); background:color-mix(in srgb,var(--accent) 15%,transparent);
  padding:2px 8px; border-radius:999px;
}

/* ---------- 底部 ---------- */
.foot{padding:clamp(30px,7vw,52px) 0 clamp(46px,10vw,80px); margin-top:clamp(18px,4vw,30px)}
.foot .wrap{border-top:.5px solid var(--separator); padding-top:clamp(26px,6vw,38px)}
.foot-cols{display:grid; grid-template-columns:1fr 1fr; gap:clamp(22px,5vw,44px)}
.foot h3{font-size:13px; font-weight:600; color:var(--label); margin-bottom:10px; letter-spacing:-.005em}
.foot p{font-size:13px; line-height:1.62; color:var(--label-2); margin-bottom:8px; letter-spacing:-.005em}
.foot p b{font-weight:600; color:var(--label-2)}
.disclaim{
  margin-top:clamp(22px,5vw,32px); padding-top:16px;
  border-top:.5px solid var(--separator);
  font-size:12px; line-height:1.6; color:var(--label-3); letter-spacing:0;
}

@media (max-width:600px){
  .foot-cols{grid-template-columns:1fr}
  .switch{flex-direction:column; align-items:stretch}
  .switch button{width:100%}

  /* 标题和计数改上下排，箭头独立定位，避免挤成两行 */
  .group summary{
    position:relative; flex-direction:column; align-items:flex-start;
    gap:2px; padding-right:44px;
  }
  .cnt{margin-left:0; font-size:13px}
  .group summary::after{position:absolute; right:20px; top:calc(50% - 6px)}
}