/* ============================================================
   设计基调：藏青(权威) × 朱砂红(印章) × 石青(立项) —— 中国学术档案
   与首页(funding-search3)、主题词分析页、学科趋势分析页同一套设计令牌
   ============================================================ */
:root{
  --page-width: 1360px;
  --page-gutter: clamp(16px,2.2vw,32px);
  --navy:        #16324A;
  --navy-deep:   #0F2336;
  --ink:         #1C1E24;
  --ink-2:       #565B66;
  --ink-3:       #8A8F9B;
  --paper:       #F7F6F2;
  --card:        #FFFFFF;
  --line:        #E3E0D8;
  --line-strong: #C9C5B9;
  --seal:        #B23A30;
  --seal-deep:   #8F2C24;
  --teal:        #2E6E63;
  --teal-soft:   #E7F0ED;
  --seal-soft:   #F7E9E7;
  --navy-soft:   #E7EDF3;
  --gold:        #A98B5F;
  --radius:      3px;
  --font-serif: "Noto Serif SC","Source Han Serif SC","Songti SC",serif;
  --font-sans:  "Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",sans-serif;
}
*{margin:0;padding:0;box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  font-family:var(--font-sans);
  font-size:15px;line-height:1.65;
  color:var(--ink);background:var(--paper);
  -webkit-font-smoothing:antialiased;
}
button,input,select,textarea{font-family:inherit;font-size:inherit;color:inherit;}
:focus-visible{outline:2px solid var(--navy);outline-offset:2px;border-radius:2px;}
::selection{background:var(--navy);color:#fff;}
.sr-only{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0;}

/* ---------- Hero（收窄版） ---------- */
.hero{
  position:relative;color:#E9EDF2;
  background:
    radial-gradient(1100px 500px at 88% -10%,rgba(178,58,48,.22),transparent 60%),
    linear-gradient(160deg,var(--navy) 0%,var(--navy-deep) 78%);
  overflow:hidden;
}
.hero::before{ /* 细网格纹理 */
  content:"";position:absolute;inset:0;
  background-image:linear-gradient(rgba(255,255,255,.045) 1px,transparent 1px),
                   linear-gradient(90deg,rgba(255,255,255,.045) 1px,transparent 1px);
  background-size:44px 44px;
  mask-image:linear-gradient(180deg,#000 0%,transparent 85%);
  -webkit-mask-image:linear-gradient(180deg,#000 0%,transparent 85%);
  pointer-events:none;
}
.hero-inner{
  position:relative;max-width:var(--page-width);margin:0 auto;
  padding:clamp(18px,2.2vw,24px) var(--page-gutter) 44px;
}
.hero h2{
  font-family:var(--font-serif);font-weight:900;color:#FFFFFF;
  font-size:clamp(22px,2.6vw,29px);line-height:1.3;letter-spacing:.02em;
  max-width:20em;
}
.hero-lede{margin-top:8px;max-width:46em;color:#AEBCCC;font-size:13.5px;line-height:1.75;}
.hero-lede strong{color:#E8D9B8;font-weight:500;}

/* ---------- 问答面板 ---------- */
.panel-wrap{max-width:var(--page-width);margin:-32px auto 80px;padding:0 var(--page-gutter);position:relative;z-index:5;}
.chat-panel{
  background:var(--card);border:1px solid var(--line);border-top:3px solid var(--navy);
  border-radius:var(--radius);box-shadow:0 14px 40px -18px rgba(15,35,54,.25);
  padding:clamp(18px,3vw,30px);
  scroll-margin-top:76px;
}
.chat-head{
  display:flex;align-items:flex-end;justify-content:space-between;gap:12px 20px;flex-wrap:wrap;
  padding-bottom:14px;border-bottom:1px solid var(--line);
}
.chat-head h3{font-family:var(--font-serif);font-size:19px;font-weight:700;color:var(--navy);letter-spacing:.05em;}
.chat-head .chat-sub{margin-top:4px;font-size:12.5px;color:var(--ink-3);}

/* 问答范围切换（沿用检索页 seg 语言；编码对齐问答接口 all/nssf/moe） */
.seg{display:inline-flex;background:#fff;border:1px solid var(--line-strong);border-radius:var(--radius);overflow:hidden;}
.seg button{
  display:inline-flex;align-items:center;gap:7px;height:38px;padding:0 16px;
  background:transparent;border:none;cursor:pointer;font-size:13.5px;color:var(--ink-2);
  transition:background .18s ease,color .18s ease;white-space:nowrap;
}
.seg button + button{border-left:1px solid var(--line-strong);}
.seg button .dot{width:8px;height:8px;border-radius:50%;flex:none;}
.seg button[data-scope="all"]  .dot{background:var(--navy);}
.seg button[data-scope="nssf"] .dot{background:var(--teal);}
.seg button[data-scope="moe"]  .dot{background:var(--seal);}
.seg button:hover{background:#F4F2EC;}
.seg button[aria-pressed="true"][data-scope="all"]{background:var(--navy);color:#fff;}
.seg button[aria-pressed="true"][data-scope="nssf"]{background:var(--teal);color:#fff;}
.seg button[aria-pressed="true"][data-scope="moe"]{background:var(--seal);color:#fff;}
.seg button[aria-pressed="true"] .dot{background:#fff;box-shadow:0 0 0 1.5px rgba(255,255,255,.55);}
@media (max-width:560px){
  .seg{width:100%;}
  .seg button{flex:1;justify-content:center;padding:0 8px;font-size:12.5px;}
}

/* ---------- 消息区（随内容增长，整页滚动） ---------- */
.msg-area{
  margin-top:16px;min-height:clamp(360px,52vh,600px);
  background:#FAF9F5;border:1px solid var(--line);border-radius:var(--radius);
  padding:20px clamp(14px,2.4vw,26px);
  display:flex;flex-direction:column;gap:18px;
}

/* 空态：印章 + 示例问题 */
.qa-empty{margin:auto;text-align:center;padding:16px 10px;max-width:600px;width:100%;}
.qa-empty .seal-empty{
  width:54px;height:54px;margin:0 auto 14px;border:1.5px solid var(--line-strong);border-radius:4px;
  display:grid;place-items:center;font-family:var(--font-serif);color:var(--line-strong);font-size:22px;transform:rotate(-4deg);
}
.qa-empty__title{font-family:var(--font-serif);font-size:17px;font-weight:700;color:var(--navy);letter-spacing:.06em;}
.qa-empty__hint{margin-top:6px;font-size:12.5px;color:var(--ink-3);}
.qa-empty__hint b{color:var(--seal);font-weight:500;}
.eg-grid{margin-top:16px;display:grid;grid-template-columns:1fr 1fr;gap:8px;}
@media (max-width:560px){.eg-grid{grid-template-columns:1fr;}}
.eg-chip{
  min-height:40px;padding:8px 14px;text-align:left;background:#fff;
  border:1px solid var(--line-strong);border-radius:var(--radius);cursor:pointer;
  font-size:13px;color:var(--ink-2);line-height:1.55;
  transition:border-color .15s ease,color .15s ease;
}
.eg-chip:hover{border-color:var(--navy);color:var(--navy);}

/* 消息 */
.msg{display:flex;align-items:flex-start;gap:10px;max-width:min(88%,46rem);}
.msg--model{align-self:flex-start;}
.msg--user{align-self:flex-end;}
@media (max-width:560px){.msg{max-width:100%;}}
.msg-avatar{
  width:34px;height:34px;flex:none;display:grid;place-items:center;border-radius:2px;
  font-family:var(--font-serif);font-weight:900;font-size:14px;line-height:1;
}
.msg-avatar--model{background:var(--seal);color:#fff;box-shadow:inset 0 0 0 1.5px rgba(255,255,255,.55);}
.msg-avatar--user{background:var(--navy);color:#fff;box-shadow:inset 0 0 0 1.5px rgba(255,255,255,.4);}
.msg-main{min-width:0;}
.msg--user .msg-main{display:flex;flex-direction:column;align-items:flex-end;}
.msg-bubble{padding:11px 15px;border-radius:var(--radius);font-size:14px;line-height:1.85;overflow-wrap:anywhere;}
.msg--model .msg-bubble{background:#fff;border:1px solid var(--line);color:var(--ink);}
.msg--user .msg-bubble{background:var(--navy);color:#F2F5F8;}
.msg-meta{margin-top:6px;display:flex;align-items:center;gap:8px;font-size:11.5px;color:var(--ink-3);font-variant-numeric:tabular-nums;}
.scope-tag{display:inline-flex;align-items:center;height:18px;padding:0 8px;border-radius:20px;font-size:11px;letter-spacing:.03em;}
.scope-tag--all{color:var(--navy);background:var(--navy-soft);}
.scope-tag--nssf{color:var(--teal);background:var(--teal-soft);}
.scope-tag--moe{color:var(--seal);background:var(--seal-soft);}

/* 气泡内的排版 */
.msg-bubble > * + *{margin-top:.55em;}
.msg-bubble ul,.msg-bubble ol{padding-left:1.35em;}
.msg-bubble li + li{margin-top:.25em;}
.msg-bubble strong{color:var(--navy);font-weight:700;}
.msg--user .msg-bubble strong{color:#fff;}
.qa-table{width:100%;border-collapse:collapse;font-size:12.5px;margin:.3em 0;}
.qa-table th{background:#F2F0E9;color:var(--ink-2);font-weight:700;text-align:left;padding:7px 10px;border-bottom:1.5px solid var(--line-strong);white-space:nowrap;}
.qa-table td{padding:7px 10px;border-bottom:1px solid var(--line);vertical-align:top;}
.stopped-note{font-size:12px;color:var(--ink-3);}

/* 流式输出中的打字光标：缀在最后一个块级元素末尾 */
.msg-bubble.is-typing > *:last-child::after{
  content:"";display:inline-block;width:8px;height:1.05em;margin-left:2px;
  background:var(--seal);vertical-align:-2px;animation:blink .8s steps(1) infinite;
}
@keyframes blink{50%{opacity:0;}}

/* 系统分隔提示 */
.sys-note{
  align-self:center;display:flex;align-items:center;gap:12px;
  width:100%;max-width:34rem;font-size:12px;color:var(--ink-3);text-align:center;
}
.sys-note::before,.sys-note::after{content:"";flex:1;height:1px;background:var(--line);}

/* 正在输入三点动画（首个增量到达前） */
.typing{display:inline-flex;gap:5px;align-items:center;height:1.4em;padding:2px 0;}
.typing i{width:6px;height:6px;border-radius:50%;background:var(--ink-3);animation:tp 1s infinite;}
.typing i:nth-child(2){animation-delay:.15s;}
.typing i:nth-child(3){animation-delay:.3s;}
@keyframes tp{0%,60%,100%{opacity:.35;transform:translateY(0);}30%{opacity:1;transform:translateY(-3px);}}

/* ---------- 输入区（吸底常驻） ---------- */
.composer-wrap{
  position:sticky;bottom:0;z-index:10;
  margin-top:16px;padding-top:16px;
  border-top:1px solid var(--line);background:var(--card);
  box-shadow:0 -10px 18px -16px rgba(15,35,54,.35);
}
.composer{display:flex;gap:12px;align-items:flex-end;}
.composer textarea{
  flex:1;min-height:44px;max-height:168px;padding:11px 13px;resize:none;
  border:1px solid var(--line-strong);border-radius:var(--radius);background:#FDFDFB;
  font-size:14.5px;line-height:1.6;
  transition:border-color .16s ease,box-shadow .16s ease;
}
.composer textarea:hover{border-color:#9AA2AF;}
.composer textarea:focus{border-color:var(--navy);box-shadow:0 0 0 3px rgba(22,50,74,.12);outline:none;}
.btn{
  height:44px;padding:0 30px;border-radius:var(--radius);cursor:pointer;flex:none;
  font-size:14.5px;font-weight:500;letter-spacing:.18em;text-indent:.18em;
  transition:background .18s ease,border-color .18s ease,color .18s ease,transform .1s ease;
}
.btn:active{transform:translateY(1px);}
.btn-primary{background:var(--navy);border:1px solid var(--navy);color:#fff;}
.btn-primary:hover{background:#1F4160;border-color:#1F4160;}
.btn.is-stop{background:var(--seal);border-color:var(--seal);}
.btn.is-stop:hover{background:var(--seal-deep);border-color:var(--seal-deep);}
.composer-bar{display:flex;align-items:center;justify-content:space-between;gap:10px 16px;flex-wrap:wrap;margin-top:10px;font-size:12px;color:var(--ink-3);}
.link-btn{border:none;background:none;color:var(--navy);font-weight:500;cursor:pointer;border-bottom:1px solid var(--navy);padding-bottom:1px;font-size:12.5px;}

/* ---------- 载入动效（一次性编排） ---------- */
@keyframes riseIn{from{opacity:0;transform:translateY(14px);}to{opacity:1;transform:none;}}
.hero-inner > *{animation:riseIn .7s cubic-bezier(.2,.7,.2,1) both;}
.hero-inner > *:nth-child(2){animation-delay:.08s;}
.panel-wrap{animation:riseIn .7s .2s cubic-bezier(.2,.7,.2,1) both;}
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none!important;transition:none!important;}
  html{scroll-behavior:auto;}
}