/* 学习乐园 · 样式 */
:root{
  --bg:#F7F8F4; --surface:#FFFFFF; --line:#E6E8E0; --ink:#2A2F2A; --ink2:#6B7268;
  --brand:#58CC02; --brand-d:#46A302; --blue:#4C8DFF; --orange:#FF9F1C; --pink:#F25C7A;
  --purple:#9B7BF0; --teal:#2EC4B6; --gold:#FFC83D;
  --r:18px; --shadow:0 2px 0 rgba(0,0,0,.06), 0 8px 24px rgba(20,30,20,.06);
  --safe-b:env(safe-area-inset-bottom,0px);
}
html[data-theme="dark"]{
  --bg:#161A18; --surface:#1F2522; --line:#2C3430; --ink:#EAF0EA; --ink2:#9AA59C;
  --shadow:0 2px 0 rgba(0,0,0,.3), 0 8px 24px rgba(0,0,0,.25);
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;height:100%}
body{
  background:var(--bg); color:var(--ink);
  font-family:-apple-system,BlinkMacSystemFont,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  font-size:17px; line-height:1.5; overscroll-behavior-y:none;
}
button{font:inherit;color:inherit;border:0;background:none;cursor:pointer}
#app{max-width:820px;margin:0 auto;min-height:100%;display:flex;flex-direction:column}

/* ---------- 顶栏 ---------- */
.topbar{
  position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:8px;
  padding:10px 14px;background:color-mix(in srgb,var(--bg) 88%,transparent);
  backdrop-filter:saturate(1.4) blur(10px);border-bottom:1px solid var(--line);
}
.tb-title{flex:1;text-align:center;font-weight:800;font-size:18px;letter-spacing:.5px}
.tb-right{display:flex;gap:6px;align-items:center}
.tb-btn{width:40px;height:40px;border-radius:12px;display:grid;place-items:center;background:var(--surface);box-shadow:var(--shadow)}
.tb-btn:active{transform:translateY(1px)}
.tb-btn svg{width:21px;height:21px}
.chip{display:flex;align-items:center;gap:5px;background:var(--surface);border-radius:999px;padding:6px 12px;font-weight:800;font-size:15px;box-shadow:var(--shadow)}
.chip svg{width:17px;height:17px}

/* ---------- 主体 ---------- */
main{flex:1;padding:16px 14px calc(90px + var(--safe-b))}
h1,h2,h3{margin:0;line-height:1.3}
h1{font-size:23px}
h2{font-size:19px}
h3{font-size:16px}
.muted{color:var(--ink2);font-size:14px}
.card{background:var(--surface);border-radius:var(--r);box-shadow:var(--shadow);padding:16px}
.stack{display:grid;gap:12px}
.row{display:flex;align-items:center;gap:10px}
.grow{flex:1}

/* ---------- 首页 ---------- */
.hero{display:flex;align-items:center;gap:14px;margin-bottom:16px}
.hero .mascot{width:64px;height:64px;flex:0 0 auto}
.hero small{color:var(--ink2)}
.subjects{display:grid;grid-template-columns:1fr 1fr 1fr;gap:10px}
@media (max-width:520px){.subjects{grid-template-columns:1fr}}
.subj{
  display:flex;align-items:center;gap:12px;padding:14px;border-radius:16px;background:var(--surface);
  box-shadow:var(--shadow);text-align:left;border:2px solid transparent;transition:border-color .15s
}
.subj:active{border-color:var(--brand)}
.subj .ico{width:46px;height:46px;border-radius:14px;display:grid;place-items:center;color:#fff;flex:0 0 auto}
.subj .ico svg{width:26px;height:26px}
.subj b{display:block;font-size:18px}
.subj span{font-size:13px;color:var(--ink2)}

/* ---------- 进度条 ---------- */
.bar{height:10px;border-radius:999px;background:color-mix(in srgb,var(--ink) 10%,transparent);overflow:hidden}
.bar>i{display:block;height:100%;border-radius:999px;background:var(--brand);transition:width .35s}

/* ---------- 关卡地图 ---------- */
.unit{
  display:flex;align-items:center;gap:14px;padding:14px;border-radius:16px;background:var(--surface);
  box-shadow:var(--shadow);margin-bottom:10px
}
.unit .badge{width:52px;height:52px;border-radius:16px;display:grid;place-items:center;color:#fff;font-weight:900;font-size:20px;flex:0 0 auto}
.unit .badge svg{width:28px;height:28px}
.unit.locked{opacity:.55}
.unit .go{margin-left:auto;padding:9px 16px;border-radius:12px;background:var(--brand);color:#fff;font-weight:800;font-size:15px}
.unit .go:disabled{background:color-mix(in srgb,var(--ink) 15%,transparent);color:var(--ink2);cursor:not-allowed}
.stars{font-size:14px;letter-spacing:2px;color:var(--gold)}
.stars .off{color:color-mix(in srgb,var(--ink) 18%,transparent)}

/* 三档：认读 / 应用 / 挑战 */
.tiers{display:flex;gap:6px;margin-top:8px;flex-wrap:wrap}
.tier{display:flex;flex-direction:column;align-items:center;gap:1px;padding:6px 11px;border-radius:11px;
  background:color-mix(in srgb,var(--ink) 5%,var(--surface));border:2px solid var(--line);font-size:12px;font-weight:800;color:var(--ink)}
.tier i{font-style:normal;font-size:9px;color:var(--gold);letter-spacing:1px}
.tier.done{border-color:var(--brand);background:color-mix(in srgb,var(--brand) 10%,var(--surface))}
.tier.locked{width:36px;justify-content:center;color:var(--ink2);opacity:.55;cursor:not-allowed}

/* ---------- 答题 ---------- */
.quizhead{display:flex;align-items:center;gap:10px;margin-bottom:10px}
.quizhead .lbl{font-weight:800;font-size:15px}
.hearts{display:flex;gap:4px}
.hearts svg{width:18px;height:18px;color:var(--pink)}
.hearts .off{color:color-mix(in srgb,var(--ink) 18%,transparent)}

.qcard{background:var(--surface);border-radius:var(--r);box-shadow:var(--shadow);padding:20px 18px}
.qtext{font-size:20px;font-weight:700;line-height:1.6;margin-bottom:16px;white-space:pre-wrap}
.qtext .en{color:var(--blue)}
.opts{display:grid;gap:10px}
.opt{
  display:flex;align-items:center;gap:12px;width:100%;text-align:left;padding:14px 16px;border-radius:14px;
  background:color-mix(in srgb,var(--ink) 4%,var(--surface));border:2px solid var(--line);font-size:18px;font-weight:600
}
.opt .k{width:28px;height:28px;border-radius:9px;display:grid;place-items:center;background:var(--surface);border:2px solid var(--line);font-size:14px;font-weight:800;flex:0 0 auto}
.opt .sp{margin-left:auto;width:34px;height:34px;border-radius:10px;display:grid;place-items:center;background:color-mix(in srgb,var(--blue) 12%,transparent);color:var(--blue);flex:0 0 auto}
.opt .sp svg{width:18px;height:18px}
.opt.right{border-color:var(--brand);background:color-mix(in srgb,var(--brand) 12%,var(--surface))}
.opt.wrong{border-color:var(--pink);background:color-mix(in srgb,var(--pink) 10%,var(--surface))}
.opt.dim{opacity:.45}
.opt:disabled{cursor:default}

.feedback{margin-top:14px;padding:14px;border-radius:14px;background:color-mix(in srgb,var(--brand) 10%,var(--surface));border-left:5px solid var(--brand);font-size:16px}
.feedback.bad{background:color-mix(in srgb,var(--pink) 10%,var(--surface));border-left-color:var(--pink)}
.playbtn{display:inline-flex;align-items:center;gap:8px;padding:12px 20px;border-radius:14px;background:var(--blue);color:#fff;font-weight:800;font-size:17px;margin-bottom:12px}
.playbtn svg{width:22px;height:22px}

/* ---------- 结算 ---------- */
.result{text-align:center;padding:24px 16px}
.result .big{font-size:52px;font-weight:900;line-height:1.1}
.result .stars{font-size:32px;letter-spacing:6px}
.kpis{display:grid;grid-template-columns:1fr 1fr 1fr;gap:10px;margin:18px 0}
.kpi{background:var(--surface);border-radius:14px;padding:12px 8px;box-shadow:var(--shadow)}
.kpi b{display:block;font-size:22px}
.kpi span{font-size:13px;color:var(--ink2)}

/* ---------- 按钮 ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:14px 22px;border-radius:14px;
  background:var(--brand);color:#fff;font-weight:800;font-size:17px;box-shadow:0 3px 0 var(--brand-d);
}
.btn:active{transform:translateY(2px);box-shadow:0 1px 0 var(--brand-d)}
.btn.block{width:100%}
.btn.ghost{background:var(--surface);color:var(--ink);box-shadow:var(--shadow)}
.btn.blue{background:var(--blue);box-shadow:0 3px 0 #2f6fd0}
.btn.sm{padding:10px 16px;font-size:15px}

/* ---------- 列表 / 表单 ---------- */
.item{display:flex;align-items:center;gap:12px;padding:12px 0;border-bottom:1px solid var(--line)}
.item:last-child{border-bottom:0}
.item .grow b{display:block}
.field{display:grid;gap:6px;margin-bottom:14px}
.field label{font-size:14px;color:var(--ink2)}
.field input[type=text],.field input[type=number],.field select{
  width:100%;padding:12px;border-radius:12px;border:2px solid var(--line);background:var(--surface);color:var(--ink);font-size:16px
}
.switch{display:flex;align-items:center;justify-content:space-between;padding:12px 0;border-bottom:1px solid var(--line)}
.switch:last-child{border-bottom:0}
.toggle{width:52px;height:30px;border-radius:999px;background:color-mix(in srgb,var(--ink) 18%,transparent);position:relative;transition:background .2s}
.toggle::after{content:'';position:absolute;top:3px;left:3px;width:24px;height:24px;border-radius:50%;background:#fff;transition:transform .2s}
.toggle.on{background:var(--brand)}
.toggle.on::after{transform:translateX(22px)}

/* ---------- 底栏 ---------- */
.tabbar{
  position:fixed;left:0;right:0;bottom:0;z-index:20;display:flex;justify-content:space-around;
  background:color-mix(in srgb,var(--surface) 94%,transparent);backdrop-filter:blur(10px);
  border-top:1px solid var(--line);padding:6px 4px calc(6px + var(--safe-b));
  max-width:820px;margin:0 auto
}
.tab{display:grid;place-items:center;gap:2px;flex:1;padding:6px 0;border-radius:12px;color:var(--ink2);font-size:11px;font-weight:700}
.tab svg{width:24px;height:24px}
.tab.on{color:var(--brand)}

/* ---------- 杂项 ---------- */
.toast{
  position:fixed;left:50%;bottom:calc(96px + var(--safe-b));transform:translate(-50%,20px);
  background:var(--ink);color:var(--bg);padding:10px 18px;border-radius:999px;font-size:15px;font-weight:700;
  opacity:0;pointer-events:none;transition:.22s;z-index:50;white-space:nowrap;max-width:88vw;overflow:hidden;text-overflow:ellipsis
}
.toast.show{opacity:1;transform:translate(-50%,0)}
.days{display:flex;align-items:flex-end;gap:8px;height:110px;padding-top:6px}
.days .d{flex:1;display:flex;flex-direction:column;justify-content:flex-end;align-items:center;gap:4px;font-size:11px;color:var(--ink2)}
.days .d i{width:100%;border-radius:8px 8px 4px 4px;background:var(--brand);min-height:4px}
.tag{display:inline-block;padding:2px 8px;border-radius:999px;background:color-mix(in srgb,var(--blue) 14%,transparent);color:var(--blue);font-size:12px;font-weight:800}
.empty{text-align:center;padding:34px 10px;color:var(--ink2)}