:root{
  --bg:#0A1622;
  --bg-elev:#0E1F30;
  --card:#12283C;
  --card-hover:#173350;
  --border:#1D3A54;
  --text:#EAF4FB;
  --text-dim:#9DC2DC;
  --text-faint:#5D82A0;
  --blue:#29B6E8;
  --blue-dark:#1888B0;
  --cyan:#7FE0F0;
  --amber:#F4A261;
  --amber-dk:#E76F51;
  --red:#E76F51;
  --purple:#8C9EFF;
  --radius:14px;
  --maxw:1180px;
}
*{box-sizing:border-box;margin:0;padding:0;}
body{
  background:var(--bg);
  color:var(--text);
  font-family:"Source Han Sans TC","Noto Sans TC","Microsoft JhengHei",sans-serif;
  line-height:1.6;
  padding-bottom:70px;
}
a{color:inherit;text-decoration:none;}
h1,h2,h3,h4{font-weight:900;}

/* ── Top Nav ── */
.topnav{
  position:sticky;top:0;z-index:50;
  background:rgba(10,22,34,0.92);
  backdrop-filter:blur(10px);
  border-bottom:1px solid var(--border);
}
.nav-inner{
  max-width:var(--maxw);margin:0 auto;
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 24px;gap:24px;
}
.brand{display:flex;align-items:center;gap:8px;font-weight:900;font-size:1.05rem;white-space:nowrap;}
.brand-icon{color:var(--blue);}
.nav-links{display:flex;gap:22px;flex-wrap:wrap;}
.nav-links a{
  display:flex;align-items:center;gap:6px;
  font-size:0.92rem;color:var(--text-dim);
  transition:color .15s;
}
.nav-links a:hover{color:var(--text);}
.nav-ic{color:var(--blue);}
.badge-count{
  background:var(--blue-dark);color:#fff;
  font-size:0.72rem;font-weight:700;
  padding:1px 7px;border-radius:20px;
}
.search{
  background:var(--card);border:1px solid var(--border);
  color:var(--text);border-radius:10px;
  padding:8px 14px;font-size:0.88rem;width:220px;
}
.search:focus{outline:1px solid var(--blue);}

/* ── Hero ── */
main{max-width:var(--maxw);margin:0 auto;padding:0 24px;}
.hero{padding:56px 0 28px;}
.pill{
  display:inline-block;background:var(--card);border:1px solid var(--border);
  color:var(--cyan);font-size:0.82rem;font-weight:700;
  padding:6px 14px;border-radius:20px;margin-bottom:18px;
}
.hero h1{font-size:2.3rem;line-height:1.3;margin-bottom:16px;max-width:820px;}
.lead{color:var(--text-dim);max-width:760px;font-size:1rem;margin-bottom:28px;}
.lead strong{color:var(--cyan);}
.stats-row{
  display:flex;flex-wrap:wrap;gap:28px;
  border-top:1px solid var(--border);
  padding-top:22px;
}
.stat{display:flex;align-items:baseline;gap:8px;color:var(--text-dim);font-size:0.85rem;}
.stat b{font-size:1.4rem;color:var(--text);font-weight:900;}
.stat-ic{color:var(--blue);}

/* ── Calculator ── */
.calculator-section{padding:36px 0 44px;border-top:1px solid var(--border);margin-top:8px;}
.calculator-intro{color:var(--text-dim);font-size:0.92rem;max-width:840px;margin-bottom:20px;}
.calculator-intro b{color:var(--cyan);}
.calc-box{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:26px;
}
.calc-tabs{display:flex;gap:10px;margin-bottom:20px;flex-wrap:wrap;}
.calc-tab{
  background:var(--bg-elev);border:1px solid var(--border);color:var(--text-dim);
  padding:8px 16px;border-radius:20px;font-size:0.86rem;font-weight:700;cursor:pointer;
}
.calc-tab.active{background:var(--blue-dark);color:#fff;border-color:var(--blue);}
.calc-panel{display:none;}
.calc-panel.active{display:grid;grid-template-columns:1.1fr 1fr;gap:28px;align-items:start;}
.calc-form{display:grid;grid-template-columns:1fr 1fr;gap:16px;}
.calc-field{display:flex;flex-direction:column;gap:6px;}
.calc-field-wide{grid-column:1 / -1;}
.calc-field label{font-size:0.82rem;color:var(--text-dim);font-weight:700;}
.calc-field input, .calc-field select{
  background:var(--bg-elev);border:1px solid var(--border);color:var(--text);
  border-radius:10px;padding:9px 12px;font-size:0.92rem;font-family:inherit;
}
.calc-field input:focus, .calc-field select:focus{outline:1px solid var(--blue);}
.calc-radio-row{display:flex;gap:10px;}
.calc-radio{
  display:flex;align-items:center;gap:6px;background:var(--bg-elev);border:1px solid var(--border);
  border-radius:10px;padding:9px 16px;font-size:0.9rem;cursor:pointer;flex:1;justify-content:center;
}
.calc-radio input{accent-color:var(--blue);}
.calc-submit{
  grid-column:1 / -1;background:linear-gradient(135deg,var(--blue),var(--blue-dark));
  color:#04212E;border:none;border-radius:10px;padding:12px;font-weight:800;font-size:0.95rem;
  cursor:pointer;margin-top:4px;
}
.calc-submit:hover{opacity:0.92;}
.calc-result{display:flex;align-items:center;justify-content:center;min-height:120px;}
.calc-result:not(.show)::before{
  content:'填好左邊的資料，按下按鈕看結果 →';
  color:var(--text-faint);font-size:0.85rem;text-align:center;
}
.calc-result.show{display:block;width:100%;}
.calc-result-grid{display:grid;gap:12px;}
.calc-result-item{
  background:var(--bg-elev);border:1px solid var(--border);border-radius:12px;
  padding:14px 16px;display:flex;align-items:center;justify-content:space-between;gap:10px;
}
.calc-result-highlight{border-color:var(--blue-dark);background:rgba(41,182,232,0.08);}
.calc-result-label{font-size:0.82rem;color:var(--text-dim);}
.calc-result-value{font-size:1.3rem;font-weight:900;color:var(--cyan);white-space:nowrap;}
.calc-result-value small{font-size:0.68rem;font-weight:600;color:var(--text-dim);}
.calc-pass{color:var(--cyan);font-weight:800;font-size:0.82rem;white-space:nowrap;}
.calc-fail{color:var(--amber);font-weight:800;font-size:0.82rem;white-space:nowrap;}
.calc-disclaimer{font-size:0.74rem;color:var(--text-faint);margin-top:12px;line-height:1.6;}

/* ── Callouts ── */
.callouts{
  display:grid;grid-template-columns:1fr 1fr;gap:16px;
  padding:24px 0;border-top:1px solid var(--border);margin-top:8px;
}
.callout{
  background:var(--card);border:1px solid var(--border);
  border-radius:var(--radius);padding:20px;
}
.callout h3{font-size:1.05rem;margin:10px 0 8px;}
.callout p{color:var(--text-dim);font-size:0.88rem;}
.tag{display:inline-block;font-size:0.72rem;font-weight:700;padding:3px 10px;border-radius:20px;}
.tag-red{background:rgba(231,111,81,0.18);color:var(--amber-dk);}
.tag-blue{background:rgba(41,182,232,0.18);color:var(--blue);}

/* ── How Section ── */
.how-section, .stages-section, .assistant-section{padding:44px 0;border-top:1px solid var(--border);}
h2{display:flex;align-items:center;gap:10px;font-size:1.4rem;margin-bottom:24px;}
.sec-ic{color:var(--blue);}
.how-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;}
.how-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:22px;
}
.how-ic{color:var(--blue);font-size:1.3rem;font-weight:900;margin-bottom:10px;}
.how-card h4{font-size:1rem;margin-bottom:8px;}
.how-card p{color:var(--text-dim);font-size:0.87rem;}

/* ── Stages / Units ── */
.stage-block{margin-bottom:32px;}
.stage-head{
  display:flex;align-items:center;gap:12px;margin-bottom:14px;
}
.stage-num{
  width:40px;height:40px;border-radius:10px;
  display:flex;align-items:center;justify-content:center;
  font-weight:900;font-size:1rem;flex-shrink:0;
}
.stage-title{font-size:1.1rem;font-weight:900;}
.stage-sub{color:var(--text-dim);font-size:0.85rem;}
.unit-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px;}
.unit-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:18px 20px;transition:border-color .15s,background .15s;
  cursor:pointer;
}
.unit-card:hover{border-color:var(--blue-dark);background:var(--card-hover);}
.unit-card:focus-visible{outline:2px solid var(--blue);outline-offset:2px;}
.unit-top{display:flex;align-items:center;gap:10px;margin-bottom:8px;}
.unit-tag{
  font-size:0.72rem;font-weight:800;color:#fff;
  padding:2px 9px;border-radius:6px;flex-shrink:0;
}
.unit-audience{font-size:0.72rem;font-weight:700;color:var(--text-faint);margin-bottom:2px;}
.unit-title{font-weight:700;font-size:0.98rem;}
.unit-topics{color:var(--text-dim);font-size:0.84rem;}
.unit-topics b{color:var(--text);font-weight:600;}
.unit-hw{
  margin-top:10px;padding-top:10px;border-top:1px dashed var(--border);
  font-size:0.8rem;color:var(--text-faint);
}
.unit-hw b{color:var(--cyan);font-weight:700;}
.unit-flag{
  margin-top:10px;background:rgba(231,111,81,0.12);border:1px solid rgba(231,111,81,0.3);
  border-radius:8px;padding:8px 10px;font-size:0.78rem;color:var(--amber);
}
.unit-more{margin-top:10px;color:var(--blue);font-size:0.8rem;font-weight:700;}

/* ── Article column ── */
.column-section{padding:44px 0;border-top:1px solid var(--border);}
.column-intro{color:var(--text-dim);max-width:760px;margin-bottom:22px;font-size:0.92rem;}
.article-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:14px;}
.article-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:18px 20px;cursor:pointer;transition:border-color .15s,background .15s;
}
.article-card:hover{border-color:var(--blue-dark);background:var(--card-hover);}
.article-card:focus-visible{outline:2px solid var(--blue);outline-offset:2px;}
.article-week{font-size:0.72rem;font-weight:800;color:var(--blue);margin-bottom:6px;}
.article-topic{font-size:0.72rem;color:var(--text-faint);margin-bottom:4px;}
.article-title{font-weight:700;font-size:0.98rem;margin-bottom:6px;}
.article-excerpt{color:var(--text-dim);font-size:0.85rem;}
.article-more{margin-top:10px;color:var(--blue);font-size:0.8rem;font-weight:700;}

/* ── Assistant ── */
.assistant-intro{color:var(--text-dim);max-width:700px;margin-bottom:22px;}
.assistant-cards{display:grid;grid-template-columns:repeat(4,1fr);gap:14px;}
.a-card{
  background:var(--card);border:1px solid var(--border);border-radius:var(--radius);
  padding:20px;
}
.a-ic{font-size:1.4rem;margin-bottom:10px;}
.a-card h4{font-size:0.95rem;margin-bottom:6px;}
.a-card p{color:var(--text-dim);font-size:0.82rem;}

/* ── Disclaimer bar ── */
.disclaimer-bar{
  position:fixed;bottom:0;left:0;right:0;z-index:60;
  background:var(--bg-elev);border-top:1px solid var(--border);
}
.disclaimer-toggle{
  width:100%;background:none;border:none;color:var(--text-faint);
  display:flex;align-items:center;justify-content:space-between;gap:16px;
  padding:10px 24px;font-size:0.78rem;cursor:pointer;text-align:left;
  max-width:var(--maxw);margin:0 auto;
}
.disclaimer-toggle strong{color:var(--amber);}
.disclaimer-bar.collapsed .disclaimer-toggle span:first-child{
  display:-webkit-box;-webkit-line-clamp:1;-webkit-box-orient:vertical;overflow:hidden;
}
.chevron{transition:transform .2s;flex-shrink:0;}
.disclaimer-bar.collapsed .chevron{transform:rotate(180deg);}

/* ── Chat FAB ── */
.chat-fab{
  position:fixed;right:24px;bottom:76px;z-index:70;
  width:56px;height:56px;border-radius:50%;
  background:linear-gradient(135deg,var(--blue),var(--blue-dark));
  color:#04212E;border:none;font-size:1.4rem;font-weight:900;
  cursor:pointer;box-shadow:0 6px 20px rgba(41,182,232,0.35);
}
.chat-fab:hover{transform:scale(1.06);}

.chat-panel{
  position:fixed;right:24px;bottom:140px;z-index:70;
  width:360px;max-width:90vw;height:480px;max-height:70vh;
  background:var(--bg-elev);border:1px solid var(--border);border-radius:16px;
  display:flex;flex-direction:column;overflow:hidden;
  box-shadow:0 20px 50px rgba(0,0,0,0.5);
  opacity:0;pointer-events:none;transform:translateY(16px);
  transition:opacity .18s, transform .18s;
}
.chat-panel.open{opacity:1;pointer-events:auto;transform:translateY(0);}
.chat-header{
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 16px;border-bottom:1px solid var(--border);
  background:var(--card);
}
.chat-title{font-weight:800;font-size:0.95rem;}
.chat-sub{font-size:0.72rem;color:var(--text-faint);}
.chat-close{background:none;border:none;color:var(--text-dim);font-size:1rem;cursor:pointer;}
.chat-messages{flex:1;overflow-y:auto;padding:14px 16px;display:flex;flex-direction:column;gap:10px;}
.msg{
  max-width:85%;padding:10px 13px;border-radius:12px;font-size:0.85rem;
  white-space:pre-wrap;line-height:1.5;
}
.msg.bot{background:var(--card);align-self:flex-start;border:1px solid var(--border);}
.msg.user{background:var(--blue-dark);color:#fff;align-self:flex-end;}
.msg.flag{background:rgba(231,111,81,0.15);border:1px solid var(--amber-dk);align-self:flex-start;}
.chat-quick{display:flex;gap:6px;padding:0 16px 10px;flex-wrap:wrap;}
.chat-quick button{
  background:var(--card);border:1px solid var(--border);color:var(--text-dim);
  font-size:0.74rem;padding:5px 10px;border-radius:20px;cursor:pointer;
}
.chat-quick button:hover{border-color:var(--blue);color:var(--text);}
.chat-input-row{display:flex;gap:8px;padding:12px;border-top:1px solid var(--border);}
.chat-input-row input{
  flex:1;background:var(--card);border:1px solid var(--border);color:var(--text);
  border-radius:10px;padding:9px 12px;font-size:0.85rem;
}
.chat-input-row input:focus{outline:1px solid var(--blue);}
.chat-input-row button{
  background:var(--blue);color:#04212E;border:none;border-radius:10px;
  padding:0 16px;font-weight:800;font-size:0.85rem;cursor:pointer;
}

/* ── Detail Modal (units & articles) ── */
.detail-modal{
  position:fixed;inset:0;z-index:80;
  background:rgba(5,11,17,0.72);backdrop-filter:blur(3px);
  display:flex;align-items:center;justify-content:center;padding:24px;
  opacity:0;pointer-events:none;transition:opacity .18s;
}
.detail-modal.open{opacity:1;pointer-events:auto;}
.detail-modal-inner{
  position:relative;background:var(--bg-elev);border:1px solid var(--border);
  border-radius:18px;max-width:680px;width:100%;max-height:85vh;overflow-y:auto;
  padding:32px 32px 28px;box-shadow:0 24px 60px rgba(0,0,0,0.55);
}
.detail-modal-close{
  position:absolute;top:16px;right:16px;background:var(--card);border:1px solid var(--border);
  color:var(--text-dim);width:32px;height:32px;border-radius:50%;cursor:pointer;font-size:0.95rem;
}
.detail-modal-close:hover{color:var(--text);}
.detail-modal-head{display:flex;align-items:flex-start;gap:14px;margin-bottom:20px;padding-right:32px;}
.detail-modal-stage{color:var(--text-dim);font-size:0.8rem;margin-bottom:4px;}
.detail-modal-head h3{font-size:1.3rem;line-height:1.4;}
#detailModalBody p{color:var(--text-dim);font-size:0.94rem;line-height:1.85;margin-bottom:14px;}
#detailModalBody p b{color:var(--cyan);font-weight:700;}
.detail-modal-hw{
  margin-top:16px;padding:14px 16px;background:var(--card);border-radius:12px;
  font-size:0.88rem;color:var(--text);
}
.detail-modal-hw b{color:var(--cyan);}
.detail-modal-source{margin-top:16px;font-size:0.76rem;color:var(--text-faint);border-top:1px dashed var(--border);padding-top:12px;}

@media (max-width:800px){
  .nav-inner{flex-wrap:wrap;padding:12px 16px;gap:10px;}
  .nav-links{
    width:100%;order:3;
    overflow-x:auto;flex-wrap:nowrap;gap:18px;
    scrollbar-width:none;
  }
  .nav-links::-webkit-scrollbar{display:none;}
  .nav-links a{white-space:nowrap;}
  .nav-actions{width:100%;order:2;}
  .search{width:100%;}
  .callouts, .how-cards, .unit-grid, .article-grid{grid-template-columns:1fr;}
  .assistant-cards{grid-template-columns:1fr 1fr;}
  .hero h1{font-size:1.7rem;}
  .calc-box .calc-panel.active{grid-template-columns:1fr;}
  .calc-form{grid-template-columns:1fr;}
}