/* =========================================================
   儿童数学思维训练营 · styles.css
   视觉风格：霓虹赛博（深色底 + 霓虹发光描边 + 网格 + 硬朗切角）
   ========================================================= */

/* ---------- 设计变量 ---------- */
:root{
  --c-primary:#c7e34f;
  --c-accent:#41d25d;
  --c-highlight:#55f1c1;
  --c-bg:#14150e;
  --c-surface:#22231a;
  --c-text:#f1f2ee;
  --c-text-dim:#aaae98;
  --c-border:#3d4030;
  --c-danger:#ff5d5d;
  --c-warn:#ffd166;

  --r:4px;             /* 圆角：4px */
  --cut:12px;          /* 硬朗切角尺寸 */

  --font-title:'Poppins','Noto Sans SC',system-ui,-apple-system,'Segoe UI',sans-serif;
  --font-mono:'JetBrains Mono','Fira Code',ui-monospace,'SFMono-Regular','Courier New',monospace;

  --glow-primary:0 0 14px rgba(199,227,79,.45);
  --glow-accent:0 0 14px rgba(65,210,93,.45);
  --glow-highlight:0 0 16px rgba(85,241,193,.5);
  --glow-danger:0 0 14px rgba(255,93,93,.45);
}

/* ---------- 基础 ---------- */
*{ box-sizing:border-box; margin:0; padding:0; }
[hidden]{ display:none !important; }

html{ scroll-behavior:smooth; -webkit-text-size-adjust:100%; }

body{
  min-height:100vh;
  color:var(--c-text);
  font-family:var(--font-mono);
  font-size:16px;
  line-height:1.7;
  background:
    radial-gradient(1100px 560px at 50% -10%, rgba(85,241,193,.10), transparent 60%),
    radial-gradient(820px 520px at 105% 105%, rgba(199,227,79,.07), transparent 60%),
    radial-gradient(700px 480px at -10% 80%, rgba(65,210,93,.06), transparent 60%),
    var(--c-bg);
  -webkit-tap-highlight-color:transparent;
  touch-action:manipulation;
}

/* 霓虹网格背景 */
body::before{
  content:""; position:fixed; inset:0; z-index:0; pointer-events:none;
  background:
    linear-gradient(rgba(61,64,48,.28) 1px, transparent 1px),
    linear-gradient(90deg, rgba(61,64,48,.28) 1px, transparent 1px);
  background-size:44px 44px;
  -webkit-mask-image:radial-gradient(ellipse 95% 75% at 50% 0%, #000 20%, transparent 78%);
          mask-image:radial-gradient(ellipse 95% 75% at 50% 0%, #000 20%, transparent 78%);
}

/* 扫描线 */
body::after{
  content:""; position:fixed; inset:0; z-index:1; pointer-events:none;
  background:repeating-linear-gradient(0deg, rgba(255,255,255,.04) 0 1px, transparent 1px 3px);
  opacity:.35; mix-blend-mode:overlay;
}

main{ position:relative; z-index:2; }

a{ color:inherit; text-decoration:none; }
button{ font:inherit; }
img, svg{ display:block; }
b{ font-weight:700; }

::selection{ background:rgba(85,241,193,.3); color:#fff; }

/* 可访问性焦点 */
:focus-visible{ outline:2px dashed var(--c-highlight); outline-offset:2px; }

/* ---------- 通用组件 ---------- */

/* 硬朗切角（用于卡片） */
.cut{
  clip-path:polygon(
    0 var(--cut), var(--cut) 0,
    100% 0,
    100% calc(100% - var(--cut)), calc(100% - var(--cut)) 100%,
    0 100%);
}

.card{
  background:linear-gradient(180deg, rgba(255,255,255,.03), rgba(255,255,255,0) 42%), var(--c-surface);
  border:1px solid var(--c-border);
  border-radius:var(--r);
}

/* 按钮 */
.btn{
  display:inline-flex; align-items:center; justify-content:center; gap:8px;
  font-family:var(--font-title); font-weight:600; font-size:15px; letter-spacing:.04em;
  color:var(--c-text); background:var(--c-surface);
  border:1px solid var(--c-border); border-radius:var(--r);
  padding:12px 22px; cursor:pointer; user-select:none;
  transition:transform .15s ease, box-shadow .2s ease, background .2s ease, color .2s, border-color .2s;
}
.btn:hover{ transform:translateY(-2px); border-color:var(--c-primary); color:var(--c-primary); box-shadow:var(--glow-primary); }
.btn:active{ transform:translateY(0); }
.btn:disabled{ opacity:.45; cursor:not-allowed; transform:none !important; box-shadow:none !important; }

.btn-primary{
  background:linear-gradient(180deg, rgba(85,241,193,.16), rgba(85,241,193,.04));
  border-color:var(--c-highlight); color:var(--c-highlight); box-shadow:var(--glow-highlight);
}
.btn-primary:hover{ background:linear-gradient(180deg, rgba(85,241,193,.3), rgba(85,241,193,.1)); color:#fff; border-color:#fff; box-shadow:0 0 22px rgba(85,241,193,.7); }

.btn-ghost{ background:transparent; }
.btn-ghost:hover{ background:rgba(199,227,79,.06); }

.btn-big{ padding:16px 34px; font-size:17px; }

/* 小标签 */
.tag{
  display:inline-flex; align-items:center; gap:10px;
  font-size:12px; letter-spacing:.24em; text-transform:uppercase; color:var(--c-highlight);
}
.tag::before{ content:""; width:20px; height:2px; background:var(--c-highlight); box-shadow:var(--glow-highlight); }

.badge{
  display:inline-block; padding:3px 12px; font-size:12px; letter-spacing:.1em;
  color:var(--c-primary); border:1px solid var(--c-primary); border-radius:var(--r);
  background:rgba(199,227,79,.07); box-shadow:var(--glow-primary);
}

/* ---------- 顶栏 ---------- */
.site-header{
  position:sticky; top:0; z-index:50;
  background:rgba(20,21,14,.85);
  border-bottom:1px solid var(--c-border);
  -webkit-backdrop-filter:blur(8px);
          backdrop-filter:blur(8px);
}
.nav-inner{
  max-width:1100px; margin:0 auto; padding:12px 20px;
  display:flex; align-items:center; gap:20px;
}
.brand{ display:flex; align-items:center; gap:10px; font-family:var(--font-title); font-weight:700; font-size:17px; letter-spacing:.02em; }
.brand .mark{ filter:drop-shadow(0 0 6px rgba(199,227,79,.55)); }
.brand-name{ white-space:nowrap; }
.nav-links{ display:flex; gap:8px; margin-left:auto; flex-wrap:wrap; }
.nav-links a{
  padding:8px 15px; font-size:14px; color:var(--c-text-dim); border:1px solid transparent; border-radius:var(--r);
  transition:color .2s, border-color .2s, box-shadow .2s, background .2s;
}
.nav-links a:hover{ color:var(--c-text); border-color:var(--c-border); }
.nav-links a.active{ color:var(--c-primary); border-color:var(--c-primary); background:rgba(199,227,79,.06); box-shadow:var(--glow-primary); }

/* ---------- 首页 · Hero ---------- */
.hero{
  max-width:1100px; margin:0 auto; padding:70px 20px 30px;
  display:grid; grid-template-columns:1.15fr .85fr; gap:40px; align-items:center;
}
.hero-title{
  font-family:var(--font-title); font-weight:800; font-size:clamp(36px, 6.2vw, 66px);
  line-height:1.06; letter-spacing:.01em; margin:16px 0 18px;
}
.hero-title .neon{
  color:var(--c-primary);
  text-shadow:0 0 10px rgba(199,227,79,.7), 0 0 32px rgba(199,227,79,.4);
}
.hero-sub{ color:var(--c-text-dim); font-size:16px; max-width:560px; }
.hero-sub b{ color:var(--c-text); }
.hero-actions{ display:flex; gap:14px; flex-wrap:wrap; margin-top:28px; }
.hero-note{ margin-top:18px; font-size:13px; color:var(--c-text-dim); letter-spacing:.05em; }

/* Hero 图形：吉祥物 + 光环 */
.hero-figure{ position:relative; display:grid; place-items:center; min-height:300px; }
.hero-figure::before{
  content:""; position:absolute; width:320px; height:320px;
  border:1.5px dashed var(--c-border); border-radius:50%;
  box-shadow:0 0 40px rgba(85,241,193,.12), inset 0 0 40px rgba(85,241,193,.06);
  animation:spin 26s linear infinite;
}
.hero-figure::after{
  content:""; position:absolute; width:250px; height:250px;
  border:1px solid rgba(199,227,79,.28); border-radius:50%;
  animation:spin 20s linear infinite reverse;
}
.mascot{ position:relative; z-index:2; width:min(300px, 78vw); filter:drop-shadow(0 8px 26px rgba(0,0,0,.55)); animation:float 5s ease-in-out infinite; }
.mascot-eye{ animation:blink 3.6s ease-in-out infinite; }

/* ---------- 首页 · 特色条 ---------- */
.strip{
  max-width:1100px; margin:24px auto 0; padding:0 20px;
  display:grid; grid-template-columns:repeat(3,1fr); gap:16px;
}
.strip-card{ padding:20px 22px; display:flex; flex-direction:column; gap:2px; transition:transform .2s, box-shadow .2s; }
.strip-card:hover{ transform:translateY(-4px); box-shadow:var(--glow-accent); }
.strip-card i{ font-style:normal; font-family:var(--font-title); font-weight:800; font-size:30px; color:var(--c-highlight); text-shadow:0 0 12px rgba(85,241,193,.6); }
.strip-card b{ font-family:var(--font-title); font-size:16px; letter-spacing:.04em; }
.strip-card span{ color:var(--c-text-dim); font-size:13px; }

/* ---------- 区块 ---------- */
.section{ max-width:1100px; margin:0 auto; padding:64px 20px 20px; }
.section-head{ margin-bottom:26px; }
.section-title{ font-family:var(--font-title); font-weight:800; font-size:clamp(26px, 4vw, 38px); margin:10px 0 8px; }
.section-title .neon{ color:var(--c-primary); text-shadow:0 0 12px rgba(199,227,79,.55); }
.section-desc{ color:var(--c-text-dim); font-size:14px; }
section[id]{ scroll-margin-top:90px; }

/* ---------- 难度选择卡片 ---------- */
.level-grid{ display:grid; grid-template-columns:repeat(3,1fr); gap:18px; }
.level-card{ padding:26px 24px 24px; display:flex; flex-direction:column; gap:14px; transition:transform .2s, box-shadow .25s, border-color .2s; }
.level-card:hover{ transform:translateY(-6px); border-color:var(--c-primary); box-shadow:0 0 26px rgba(199,227,79,.25); filter:drop-shadow(0 10px 20px rgba(0,0,0,.35)); }
.level-top{ display:flex; align-items:center; gap:14px; }
.level-icon{ width:52px; height:52px; display:grid; place-items:center; border:1px solid var(--c-border); border-radius:var(--r); background:rgba(255,255,255,.02); flex:none; }
.level-icon svg{ filter:drop-shadow(0 0 6px rgba(85,241,193,.35)); }
.level-top h3{ font-family:var(--font-title); font-weight:700; font-size:20px; }
.grade{ font-size:12px; letter-spacing:.14em; color:var(--c-text-dim); }
.meter{ display:flex; gap:5px; margin-left:auto; }
.meter i{ width:12px; height:22px; background:linear-gradient(180deg, var(--c-highlight), var(--c-accent)); box-shadow:var(--glow-accent); }
.meter i.off{ background:var(--c-border); box-shadow:none; }
.level-desc{ color:var(--c-text-dim); font-size:14px; min-height:64px; }
.level-card .btn{ margin-top:auto; width:100%; }

/* ---------- 排行榜 ---------- */
.lb-card{ padding:0; overflow:hidden; }
.lb-head, .lb-row{
  display:grid; grid-template-columns:64px 1fr auto auto; gap:12px; align-items:center;
  padding:14px 22px; font-size:14px;
}
.lb-head{ color:var(--c-text-dim); font-size:12px; letter-spacing:.16em; border-bottom:1px solid var(--c-border); background:rgba(255,255,255,.02); }
.lb-row{ border-bottom:1px solid rgba(61,64,48,.55); animation:fadeUp .45s ease both; }
.lb-row:last-child{ border-bottom:none; }
.lb-row.top{ background:linear-gradient(90deg, rgba(199,227,79,.07), transparent 60%); }
.lb-rank{ display:flex; align-items:center; }
.lb-rank .rank{ width:26px; height:26px; display:grid; place-items:center; font-size:13px; border:1px solid var(--c-border); border-radius:var(--r); color:var(--c-text-dim); }
.lb-name{ font-family:var(--font-title); font-weight:600; letter-spacing:.03em; overflow:hidden; text-overflow:ellipsis; white-space:nowrap; }
.lb-tags{ display:flex; gap:6px; }
.lb-tags i{ font-style:normal; font-size:11px; color:var(--c-text-dim); border:1px solid var(--c-border); border-radius:var(--r); padding:2px 8px; }
.lb-score{ font-weight:700; color:var(--c-highlight); text-shadow:0 0 10px rgba(85,241,193,.5); }
.lb-empty{ padding:46px 20px; text-align:center; color:var(--c-text-dim); }
.lb-empty svg{ margin:0 auto 14px; filter:drop-shadow(0 0 10px rgba(199,227,79,.35)); }

/* ---------- 页脚 ---------- */
.site-footer{
  position:relative; z-index:2; margin-top:80px; padding:26px 20px 34px;
  text-align:center; color:var(--c-text-dim); font-size:13px;
  border-top:1px solid var(--c-border); background:rgba(20,21,14,.7);
}
.site-footer span{ color:var(--c-highlight); }

/* ---------- 子页顶部 ---------- */
.page-top{ max-width:1100px; margin:0 auto; padding:44px 20px 10px; }
.crumbs{ font-size:13px; color:var(--c-text-dim); margin-bottom:10px; }
.crumbs a{ color:var(--c-highlight); }
.crumbs a:hover{ text-shadow:0 0 8px rgba(85,241,193,.6); }
.page-title{ font-family:var(--font-title); font-weight:800; font-size:clamp(30px, 5vw, 46px); margin-bottom:8px; }
.page-title .neon{ color:var(--c-primary); text-shadow:0 0 12px rgba(199,227,79,.55); }
.page-desc{ color:var(--c-text-dim); font-size:14px; }

/* ---------- 谜题页 · 选择区 ---------- */
.setup{ max-width:680px; margin:28px auto 0; padding:28px 28px 30px; display:flex; flex-direction:column; gap:22px; }
.setup-row{ display:flex; flex-direction:column; gap:10px; }
.setup-label{ font-size:12px; letter-spacing:.2em; color:var(--c-text-dim); text-transform:uppercase; }
.btn-group{ display:flex; gap:10px; flex-wrap:wrap; }
.btn-group .btn{ flex:1; min-width:110px; }
.lvl-btn.active{ border-color:var(--c-primary); color:var(--c-primary); background:rgba(199,227,79,.07); box-shadow:var(--glow-primary); }
.cat-tab.active{ border-color:var(--c-highlight); color:var(--c-highlight); background:rgba(85,241,193,.07); box-shadow:var(--glow-highlight); }
.setup-info{
  border:1px dashed var(--c-border); border-radius:var(--r); padding:14px 18px;
  font-family:var(--font-title); color:var(--c-text);
}
.setup-info p{ color:var(--c-text-dim); font-family:var(--font-mono); font-size:13px; margin-top:2px; }
.setup .btn-primary{ width:100%; }

/* ---------- 谜题页 · 游戏中 ---------- */
.game{ max-width:680px; margin:28px auto 0; padding:24px 26px 30px; }
.statusbar{ display:flex; gap:12px; flex-wrap:wrap; margin-bottom:16px; }
.stat{
  display:flex; align-items:center; gap:8px; padding:8px 14px;
  border:1px solid var(--c-border); border-radius:var(--r); background:rgba(0,0,0,.18);
  font-family:var(--font-mono); font-size:14px; color:var(--c-text);
}
.stat b{ color:var(--c-text); }
.stat svg{ flex:none; }

.progress{ height:8px; background:var(--c-border); border-radius:var(--r); overflow:hidden; margin-bottom:22px; }
.progress > i{
  display:block; height:100%; width:0%;
  background:linear-gradient(90deg, var(--c-primary), var(--c-highlight));
  box-shadow:var(--glow-primary); transition:width .35s ease;
}

.qcard{ text-align:center; }
.qcard .badge{ margin-bottom:16px; }
.qtext{
  font-family:var(--font-title); font-weight:700; font-size:clamp(22px, 4vw, 30px);
  line-height:1.5; margin:6px 0 22px; min-height:3em;
}

/* 数独 4×4 网格 */
.sudoku{ display:grid; grid-template-columns:repeat(4,1fr); gap:6px; max-width:300px; margin:0 auto 20px; }
.sudoku .cell{
  aspect-ratio:1; display:grid; place-items:center;
  font-family:var(--font-mono); font-weight:700; font-size:28px; color:var(--c-text);
  background:rgba(0,0,0,.2); border:1px solid var(--c-border); border-radius:var(--r);
}
.sudoku .cell.blank{
  color:var(--c-primary); border-color:var(--c-primary);
  box-shadow:inset 0 0 14px rgba(199,227,79,.25), 0 0 10px rgba(199,227,79,.25);
  animation:blink 1.2s ease-in-out infinite;
}

/* 选项 */
.options{ display:grid; grid-template-columns:repeat(2,1fr); gap:12px; max-width:560px; margin:0 auto; }
.option{ padding:18px 14px; font-size:clamp(18px, 3vw, 22px); font-family:var(--font-mono); font-weight:700; }
.option.correct{ border-color:var(--c-accent); color:var(--c-accent); background:rgba(65,210,93,.13); box-shadow:var(--glow-accent); animation:popIn .32s ease; }
.option.wrong{ border-color:var(--c-danger); color:var(--c-danger); background:rgba(255,93,93,.1); animation:shake .35s ease; }

/* 反馈条 */
.feedback{
  min-height:30px; margin:20px 0 0; font-size:14px; color:var(--c-text-dim);
  display:flex; align-items:center; justify-content:center; gap:6px;
}
.feedback.good{ color:var(--c-accent); text-shadow:0 0 10px rgba(65,210,93,.5); }
.feedback.bad{ color:var(--c-warn); }

/* ---------- 谜题页 · 结算 ---------- */
.end{ max-width:640px; margin:28px auto 0; padding:36px 30px 32px; text-align:center; position:relative; overflow:hidden; }
.end-title{ font-family:var(--font-title); font-weight:800; font-size:clamp(26px, 5vw, 40px); margin-bottom:24px; }
.end-stats{ display:grid; grid-template-columns:repeat(3,1fr); gap:12px; margin-bottom:24px; }
.end-stat{ border:1px solid var(--c-border); border-radius:var(--r); padding:16px 10px; background:rgba(0,0,0,.18); }
.end-stat span{ display:block; font-size:12px; letter-spacing:.18em; color:var(--c-text-dim); margin-bottom:6px; }
.end-stat b{ font-family:var(--font-title); font-size:26px; color:var(--c-highlight); text-shadow:0 0 14px rgba(85,241,193,.55); }
.save-row{ display:flex; gap:12px; max-width:460px; margin:0 auto 10px; }
.save-row input{
  flex:1; min-width:0; padding:13px 16px; font-family:var(--font-mono); font-size:15px;
  color:var(--c-text); background:rgba(0,0,0,.25); border:1px solid var(--c-border); border-radius:var(--r);
  transition:border-color .2s, box-shadow .2s;
}
.save-row input:focus{ outline:none; border-color:var(--c-highlight); box-shadow:var(--glow-highlight); }
.save-row input::placeholder{ color:var(--c-text-dim); }
.save-tip{ font-size:13px; color:var(--c-accent); margin:0 0 18px; min-height:20px; }
.lb-mini{ margin-bottom:24px; }
.end-actions{ display:flex; gap:12px; justify-content:center; flex-wrap:wrap; }

/* 结算页星形粒子 */
.spark{
  position:absolute; width:12px; height:12px; pointer-events:none; z-index:3;
  background:var(--c-primary); box-shadow:0 0 10px rgba(199,227,79,.8);
  clip-path:polygon(50% 0%, 61% 35%, 98% 35%, 68% 57%, 79% 91%, 50% 70%, 21% 91%, 32% 57%, 2% 35%, 39% 35%);
  opacity:0; animation:sparkPop 2.6s ease-in-out infinite;
}

/* ---------- 每日一题页 ---------- */
.daily-head{ max-width:680px; margin:26px auto 0; padding:0 20px; display:grid; grid-template-columns:1.2fr .8fr; gap:14px; }
.daily-date, .daily-streak{ padding:16px 20px; display:flex; flex-direction:column; gap:2px; }
.d-label{ font-size:11px; letter-spacing:.22em; color:var(--c-text-dim); }
.daily-date b{ font-family:var(--font-title); font-size:18px; }
.daily-streak{ flex-direction:row; align-items:center; gap:12px; }
.daily-streak b{ font-family:var(--font-title); font-weight:800; font-size:34px; color:var(--c-warn); text-shadow:0 0 14px rgba(255,209,102,.55); }
.daily-streak .flame svg{ filter:drop-shadow(0 0 8px rgba(255,209,102,.6)); }

.daily-q{ max-width:680px; margin:18px auto 0; padding:28px 28px 30px; text-align:center; }
.daily-q-top{ display:flex; align-items:center; justify-content:space-between; gap:10px; flex-wrap:wrap; }
.d-count{ font-size:12px; color:var(--c-text-dim); letter-spacing:.08em; }
.explain{
  text-align:left; margin-top:20px; padding:18px 20px;
  border:1px solid var(--c-highlight); border-radius:var(--r);
  background:rgba(85,241,193,.05); box-shadow:var(--glow-highlight);
  animation:fadeUp .4s ease both;
}
.explain .tag{ margin-bottom:10px; }
.explain p{ font-size:15px; color:var(--c-text); }
.daily-actions{ margin-top:24px; }
.daily-note{ margin-top:16px; font-size:13px; color:var(--c-text-dim); }

/* ---------- 动画 ---------- */
@keyframes spin{ to{ transform:rotate(360deg); } }
@keyframes float{ 0%,100%{ transform:translateY(0); } 50%{ transform:translateY(-12px); } }
@keyframes blink{ 0%,92%,100%{ transform:scaleY(1); } 95%{ transform:scaleY(.08); } }
@keyframes fadeUp{ from{ opacity:0; transform:translateY(12px); } to{ opacity:1; transform:translateY(0); } }
@keyframes popIn{ 0%{ transform:scale(.9); } 60%{ transform:scale(1.06); } 100%{ transform:scale(1); } }
@keyframes shake{ 0%,100%{ transform:translateX(0); } 25%{ transform:translateX(-7px); } 55%{ transform:translateX(6px); } 80%{ transform:translateX(-3px); } }
@keyframes sparkPop{
  0%{ opacity:0; transform:scale(.3) rotate(0); }
  30%{ opacity:1; transform:scale(1) rotate(45deg); }
  70%{ opacity:.85; }
  100%{ opacity:0; transform:scale(.4) rotate(140deg) translateY(-16px); }
}

/* ---------- 响应式 ---------- */
@media (max-width: 880px){
  .hero{ grid-template-columns:1fr; padding-top:44px; }
  .hero-figure{ order:-1; min-height:240px; }
  .hero-figure::before{ width:250px; height:250px; }
  .hero-figure::after{ width:190px; height:190px; }
  .strip{ grid-template-columns:1fr; }
  .level-grid{ grid-template-columns:1fr; }
  .daily-head{ grid-template-columns:1fr; }
  .nav-inner{ flex-wrap:wrap; }
  .brand-name{ font-size:15px; }
}
@media (max-width: 520px){
  .options{ grid-template-columns:1fr; }
  .end-stats{ grid-template-columns:1fr; }
  .save-row{ flex-direction:column; }
  .lb-head, .lb-row{ grid-template-columns:44px 1fr auto; }
  .lb-tags{ display:none; }
  .btn-group .btn{ min-width:0; flex:1 1 46%; }
}

/* ---------- 减弱动效 ---------- */
@media (prefers-reduced-motion: reduce){
  *, *::before, *::after{ animation-duration:.001s !important; animation-iteration-count:1 !important; transition-duration:.001s !important; }
  html{ scroll-behavior:auto; }
}