/* ==========================================================================
   车商AI对话助手 · 样式（橙 + 白，阳光感）
   ========================================================================== */

:root {
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
          "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --mono: "SFMono-Regular", ui-monospace, Menlo, Consolas, "Liberation Mono", monospace;
  --radius: 14px;
  --sidebar-w: 268px;
  --ease: cubic-bezier(.22, .61, .36, 1);
}

html[data-theme="light"] {
  --bg: #ffffff;
  --bg-soft: #fff8f1;
  --panel: #ffffff;
  --panel-2: #fff3e6;
  --border: #f2e3d3;
  --border-strong: #e8d2bb;
  --text: #2a1f14;
  --text-2: #6b5847;
  --text-3: #9c8873;
  --accent: #f97316;
  --accent-hover: #ea6a0b;
  --accent-soft: #fff0e0;
  --user-bubble: #fff1df;
  --code-bg: #fff9f3;
  --code-head: #fdf0e2;
  --shadow: 0 1px 2px rgba(120, 70, 20, .06), 0 8px 24px rgba(120, 70, 20, .07);
  --shadow-sm: 0 1px 3px rgba(120, 70, 20, .1);
  --overlay: rgba(60, 40, 20, .42);
  --sun-a: rgba(255, 176, 32, .22);
  --sun-b: rgba(249, 115, 22, .1);
}

html[data-theme="dark"] {
  --bg: #1b1713;
  --bg-soft: #231d18;
  --panel: #262019;
  --panel-2: #302720;
  --border: #3a2f26;
  --border-strong: #4a3c30;
  --text: #f5ede4;
  --text-2: #bfae9c;
  --text-3: #8c7b69;
  --accent: #ff8a3d;
  --accent-hover: #ff9c59;
  --accent-soft: #3a2718;
  --user-bubble: #3a2718;
  --code-bg: #16120f;
  --code-head: #221b15;
  --shadow: 0 1px 2px rgba(0, 0, 0, .35), 0 10px 30px rgba(0, 0, 0, .34);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, .4);
  --overlay: rgba(0, 0, 0, .62);
  --sun-a: rgba(255, 150, 60, .16);
  --sun-b: rgba(255, 110, 30, .08);
}

* { box-sizing: border-box; }

/* 带 display 声明的元素也要能被 hidden 隐藏 */
[hidden] { display: none !important; }

html, body { height: 100%; margin: 0; padding: 0; }

body {
  font-family: var(--font);
  font-size: 15px;
  line-height: 1.7;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  overflow: hidden;
}

button { font-family: inherit; cursor: pointer; }
input, textarea { font-family: inherit; }
::selection { background: var(--accent-soft); }

.scroll-y { scrollbar-width: thin; scrollbar-color: var(--border-strong) transparent; }
.scroll-y::-webkit-scrollbar { width: 8px; height: 8px; }
.scroll-y::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 8px;
  border: 2px solid transparent;
  background-clip: content-box;
}
.scroll-y::-webkit-scrollbar-track { background: transparent; }

/* 高度：老浏览器不认识 dvh，先给 100% 兜底，现代浏览器再用 dvh 覆盖 */
.app {
  display: flex;
  height: 100%;
  height: 100dvh;
  overflow: hidden;
}

/* ==========================================================================
   侧边栏
   ========================================================================== */

.sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  background: var(--bg-soft);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  min-height: 0;
  transition: margin-left .24s var(--ease);
}

body.sb-hidden .sidebar { margin-left: calc(var(--sidebar-w) * -1); }

.sb-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 12px 10px 16px;
}
.brand { display: flex; align-items: center; gap: 8px; min-width: 0; }
.brand-mark {
  width: 26px; height: 26px; flex: none;
  display: grid; place-items: center;
  border-radius: 9px;
  background: linear-gradient(145deg, #ffb020, #f97316);
  color: #fff;
  box-shadow: 0 2px 8px rgba(249, 115, 22, .3);
}
.brand-name {
  font-size: 14.5px; font-weight: 600; letter-spacing: .2px; white-space: nowrap;
  overflow: hidden; text-overflow: ellipsis;
}

.icon-btn {
  width: 32px; height: 32px; flex: none;
  display: grid; place-items: center;
  border: none; border-radius: 9px;
  background: transparent; color: var(--text-2);
  transition: background .15s, color .15s;
}
.icon-btn:hover { background: var(--panel-2); color: var(--text); }
.icon-btn:active { transform: scale(.95); }
.icon-btn:disabled { opacity: .4; cursor: not-allowed; }

.new-chat-btn {
  margin: 4px 12px 10px;
  height: 40px;
  display: flex; align-items: center; justify-content: center; gap: 8px;
  padding: 0 14px;
  border: none; border-radius: 11px;
  background: linear-gradient(135deg, #fb923c, #f97316);
  color: #fff;
  font-size: 14.5px; font-weight: 550;
  transition: filter .15s, transform .12s;
  box-shadow: 0 3px 12px rgba(249, 115, 22, .28);
}
.new-chat-btn:hover { filter: brightness(1.05); }
.new-chat-btn:active { transform: scale(.985); }

.sb-search {
  margin: 0 12px 8px;
  display: flex; align-items: center; gap: 7px;
  padding: 0 10px;
  height: 34px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--panel);
  color: var(--text-3);
}
.sb-search:focus-within { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.sb-search input {
  flex: 1; min-width: 0;
  border: none; outline: none; background: transparent;
  color: var(--text); font-size: 13.5px;
}

.conv-list { flex: 1; min-height: 0; overflow-y: auto; padding: 4px 8px 10px; }
.conv-group { padding: 10px 8px 4px; font-size: 12px; color: var(--text-3); }

.conv-item {
  position: relative;
  display: flex; align-items: center;
  gap: 8px; width: 100%;
  padding: 8px 30px 8px 10px;
  border: none; border-radius: 10px;
  background: transparent;
  color: var(--text-2);
  font-size: 14px; text-align: left;
  transition: background .13s, color .13s;
}
.conv-item:hover { background: var(--panel-2); color: var(--text); }
.conv-item.active { background: var(--accent-soft); color: var(--text); font-weight: 550; }
.conv-item .ci-text {
  flex: 1; min-width: 0;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.conv-item .ci-del {
  position: absolute; right: 6px; top: 50%; transform: translateY(-50%);
  width: 22px; height: 22px; display: grid; place-items: center;
  border: none; border-radius: 7px; background: transparent;
  color: var(--text-3); opacity: 0;
  transition: opacity .13s, background .13s, color .13s;
}
.conv-item:hover .ci-del { opacity: 1; }
.conv-item .ci-del:hover { background: rgba(229, 72, 77, .14); color: #e5484d; }

.conv-empty { padding: 18px 12px; font-size: 13px; color: var(--text-3); }

.sb-foot {
  border-top: 1px solid var(--border);
  padding: 8px;
  display: flex; flex-direction: column; gap: 2px;
}
.foot-btn {
  display: flex; align-items: center; gap: 9px;
  padding: 9px 10px;
  border: none; border-radius: 10px;
  background: transparent; color: var(--text-2);
  font-size: 13.5px; text-align: left;
  transition: background .13s, color .13s;
}
.foot-btn:hover { background: var(--panel-2); color: var(--text); }
html[data-theme="light"] .ico-moon,
html[data-theme="dark"] .ico-sun { display: none; }

.sb-mask {
  display: none;
  position: fixed;
  top: 0; right: 0; bottom: 0; left: 0;
  z-index: 60;
  background: var(--overlay);
  -webkit-backdrop-filter: blur(1px);
  backdrop-filter: blur(1px);
}

/* ==========================================================================
   主区域
   ========================================================================== */

.main {
  flex: 1; min-width: 0;
  display: flex; flex-direction: column;
  background: var(--bg);
  position: relative;
}

/* 顶部阳光光晕 */
.main::before {
  content: "";
  position: absolute; top: -170px; left: 50%;
  width: 640px; height: 330px; margin-left: -320px;
  background: radial-gradient(closest-side, var(--sun-a), var(--sun-b) 55%, transparent 100%);
  pointer-events: none;
  z-index: 0;
}

.topbar {
  height: 56px; flex: none;
  display: flex; align-items: center; gap: 8px;
  padding: 0 14px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  background: color-mix(in srgb, var(--bg) 86%, transparent);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  position: relative; z-index: 10;
}

.topbar-right {
  margin-left: auto;
  display: flex; align-items: center; gap: 6px;
  min-width: 0;
}
.chat-title {
  font-size: 13.5px; color: var(--text-3);
  max-width: 34vw;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}

.model-picker { position: relative; }
.model-btn {
  display: flex; align-items: center; gap: 7px;
  height: 34px; padding: 0 10px 0 11px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--panel);
  color: var(--text);
  font-size: 14px; font-weight: 550;
  transition: border-color .15s, background .15s;
}
.model-btn:hover:not(:disabled) { border-color: var(--border-strong); }
.model-btn:disabled { color: var(--text-3); font-weight: 400; cursor: default; }
.model-dot {
  width: 7px; height: 7px; border-radius: 50%; flex: none;
  background: linear-gradient(145deg, #ffb020, #f97316);
  box-shadow: 0 0 0 3px rgba(249, 115, 22, .16);
}
.model-btn.bad .model-dot { background: #e5484d; box-shadow: 0 0 0 3px rgba(229, 72, 77, .16); }
.model-name { max-width: 190px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.model-btn .caret { color: var(--text-3); transition: transform .18s; }
.model-picker.open .model-btn .caret { transform: rotate(180deg); }

.model-menu {
  position: absolute; top: calc(100% + 6px); left: 0; z-index: 40;
  width: 400px;
  max-width: 84vw;
  width: min(400px, 84vw);
  max-height: 460px;
  max-height: min(60vh, 460px);
  overflow-y: auto;
  padding: 6px;
  border: 1px solid var(--border);
  border-radius: 13px;
  background: var(--panel);
  box-shadow: var(--shadow);
}
.model-item {
  width: 100%;
  display: flex; align-items: flex-start; gap: 10px;
  padding: 10px 11px;
  border: none; border-radius: 10px;
  background: transparent;
  color: var(--text); text-align: left;
  transition: background .13s;
}
.model-item:hover { background: var(--panel-2); }
.model-item.selected { background: var(--accent-soft); }
.model-item[disabled] { opacity: .45; cursor: not-allowed; }
.mi-main { flex: 1; min-width: 0; }
.mi-name { display: flex; align-items: center; gap: 6px; font-size: 14px; font-weight: 550; flex-wrap: wrap; }
.mi-desc {
  margin-top: 2px; font-size: 12.5px; line-height: 1.5; color: var(--text-3);
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden;
}
.mi-check { color: var(--accent); flex: none; margin-top: 2px; }
.badge {
  font-size: 11px; font-weight: 500; line-height: 1;
  padding: 3px 6px; border-radius: 6px;
  background: var(--panel-2); color: var(--text-2);
  border: 1px solid var(--border);
}
.badge.vision { background: var(--accent-soft); color: var(--accent); border-color: transparent; }
.badge.rec { background: #fff3d6; color: #a8611a; border-color: transparent; }
html[data-theme="dark"] .badge.rec { background: #3a2c14; color: #f0b566; }
.badge.free { background: #eaf7e8; color: #3b8a34; border-color: transparent; }
html[data-theme="dark"] .badge.free { background: #22301f; color: #86d17f; }
.menu-note { padding: 10px 12px; font-size: 12.5px; line-height: 1.6; color: var(--text-3); }
.menu-sep { height: 1px; margin: 5px 8px; background: var(--border); }

.banner-wrap { position: relative; z-index: 5; }
.banner {
  display: flex; align-items: center; gap: 9px;
  margin: 10px 16px 0;
  padding: 10px 13px;
  border-radius: 11px;
  font-size: 13.5px;
  background: var(--panel-2);
  color: var(--text-2);
}
.banner.warn { background: rgba(229, 72, 77, .1); color: #c23b3f; }
.banner.info { background: var(--accent-soft); color: var(--accent); }
html[data-theme="dark"] .banner.warn { color: #ff8b8f; }
.banner .b-close { margin-left: auto; }

/* ==========================================================================
   对话区
   ========================================================================== */

.chat {
  flex: 1; min-height: 0;
  overflow-y: auto;
  position: relative;
  scroll-behavior: smooth;
  z-index: 1;
}

.welcome { min-height: 100%; display: grid; place-items: center; padding: 30px 20px 10px; }
.welcome-inner { max-width: 660px; width: 100%; text-align: center; }
.welcome-mark {
  width: 64px; height: 64px; margin: 0 auto 16px;
  display: grid; place-items: center;
  border-radius: 20px;
  background: linear-gradient(150deg, #ffc247, #f97316);
  color: #fff;
  box-shadow: 0 8px 26px rgba(249, 115, 22, .3);
}
.welcome h1 { margin: 0 0 8px; font-size: 25px; font-weight: 650; letter-spacing: -.2px; }
.welcome-sub { margin: 0 0 26px; color: var(--text-2); font-size: 14.5px; }
.chips { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 9px; }
.chip {
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--panel);
  color: var(--text-2);
  font-size: 13.5px; text-align: left;
  transition: border-color .15s, background .15s, color .15s, transform .12s;
}
.chip:hover { border-color: var(--accent); color: var(--text); background: var(--accent-soft); }
.chip:active { transform: scale(.99); }

.msg-list { max-width: 820px; margin: 0 auto; padding: 22px 20px 26px; }

.msg { display: flex; gap: 12px; margin-bottom: 26px; animation: fadeUp .26s var(--ease); }
@keyframes fadeUp { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

.avatar {
  width: 32px; height: 32px; flex: none;
  border-radius: 10px;
  display: grid; place-items: center;
  font-size: 12.5px; font-weight: 600;
}
.msg.assistant .avatar { background: linear-gradient(150deg, #ffc247, #f97316); color: #fff; }
.msg.user .avatar { background: var(--panel-2); color: var(--text-2); border: 1px solid var(--border); }

.msg-body { flex: 1; min-width: 0; }

.bubble {
  padding: 12px 15px;
  border-radius: 13px;
  background: var(--user-bubble);
  white-space: pre-wrap;
  word-break: break-word;
  font-size: 14.8px;
}
.msg.user .msg-body { display: flex; flex-direction: column; align-items: flex-end; }
.msg.user .msg-content { max-width: 100%; }

.msg-imgs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 8px; justify-content: flex-end; }
.msg-imgs img {
  width: 112px; height: 112px; object-fit: cover;
  border-radius: 11px; border: 1px solid var(--border);
  cursor: zoom-in; transition: transform .15s;
}
.msg-imgs img:hover { transform: scale(1.02); }

.answer { font-size: 15px; word-break: break-word; }
.answer > *:first-child { margin-top: 0; }
.answer > *:last-child { margin-bottom: 0; }
.answer p { margin: 0 0 12px; }
.answer h1, .answer h2, .answer h3, .answer h4, .answer h5, .answer h6 {
  margin: 20px 0 10px; line-height: 1.4; font-weight: 650;
}
.answer h1 { font-size: 21px; }
.answer h2 { font-size: 18.5px; }
.answer h3 { font-size: 16.5px; }
.answer h4, .answer h5, .answer h6 { font-size: 15.5px; }
.answer ul, .answer ol { margin: 0 0 12px; padding-left: 22px; }
.answer li { margin: 3px 0; }
.answer li > p { margin: 0; }
.answer blockquote {
  margin: 0 0 12px; padding: 6px 14px;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 8px 8px 0;
  color: var(--text-2);
}
.answer hr { border: none; border-top: 1px solid var(--border); margin: 18px 0; }
.answer a { color: var(--accent); text-decoration: none; }
.answer a:hover { text-decoration: underline; }
/* 行内代码：不用 :not(pre code) 这种嵌套选择器，老浏览器会整条丢弃 */
.answer code {
  font-family: var(--mono); font-size: .89em;
  padding: 2px 5px; border-radius: 5px;
  background: var(--code-bg);
  border: 1px solid var(--border);
  color: #c2410c;
}
html[data-theme="dark"] .answer code { color: #ffab6b; }
.answer table {
  width: 100%; border-collapse: collapse;
  margin: 0 0 14px; font-size: 13.8px;
  display: block; overflow-x: auto;
}
.answer th, .answer td { border: 1px solid var(--border); padding: 7px 11px; text-align: left; }
.answer th { background: var(--panel-2); font-weight: 600; }

.code-block {
  margin: 0 0 14px;
  border: 1px solid var(--border);
  border-radius: 11px;
  overflow: hidden;
  background: var(--code-bg);
}
.code-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 6px 8px 6px 12px;
  background: var(--code-head);
  border-bottom: 1px solid var(--border);
}
.code-lang { font-size: 12px; color: var(--text-3); font-family: var(--mono); }
.code-copy {
  border: none; border-radius: 7px;
  padding: 4px 9px;
  background: transparent; color: var(--text-2);
  font-size: 12px;
  transition: background .13s, color .13s;
}
.code-copy:hover { background: var(--panel-2); color: var(--accent); }
.code-block pre { margin: 0; overflow-x: auto; }
.code-block pre code {
  display: block;
  padding: 13px 14px;
  border: none;
  border-radius: 0;
  background: none;
  font-family: var(--mono);
  font-size: 13.2px; line-height: 1.65;
  white-space: pre;
  color: var(--text);
}

.think-box {
  margin-bottom: 12px;
  border: 1px solid var(--border);
  border-radius: 11px;
  background: var(--panel-2);
  overflow: hidden;
}
.think-head {
  display: flex; align-items: center; gap: 7px;
  width: 100%; padding: 8px 12px;
  border: none; background: transparent;
  color: var(--text-2); font-size: 13px; text-align: left;
}
.think-head:hover { color: var(--text); }
.think-head .caret { transition: transform .18s; margin-left: auto; }
.think-box.open .think-head .caret { transform: rotate(180deg); }
.think-body {
  display: none;
  padding: 9px 12px 11px;
  font-size: 13.2px; line-height: 1.7;
  color: var(--text-2);
  white-space: pre-wrap;
  border-top: 1px dashed var(--border);
  max-height: 300px; overflow-y: auto;
}
.think-box.open .think-body { display: block; }

.typing { display: inline-flex; gap: 4px; align-items: center; height: 22px; }
.typing i {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent); opacity: .5;
  animation: blink 1.25s infinite ease-in-out;
}
.typing i:nth-child(2) { animation-delay: .16s; }
.typing i:nth-child(3) { animation-delay: .32s; }
@keyframes blink { 0%, 70%, 100% { opacity: .28; transform: translateY(0); } 35% { opacity: 1; transform: translateY(-3px); } }

.caret-blink {
  display: inline-block; width: 7px; height: 15px;
  vertical-align: -2px; margin-left: 2px;
  background: var(--accent);
  animation: caret 1s steps(2) infinite;
  border-radius: 1px;
}
@keyframes caret { 0%, 50% { opacity: 1; } 50.01%, 100% { opacity: 0; } }

.msg-actions {
  display: flex; align-items: center; gap: 2px;
  margin-top: 8px; opacity: 0;
  transition: opacity .16s;
}
.msg:hover .msg-actions, .msg-actions.pinned { opacity: 1; }
.act-btn {
  display: inline-flex; align-items: center; gap: 5px;
  height: 28px; padding: 0 9px;
  border: none; border-radius: 8px;
  background: transparent; color: var(--text-3);
  font-size: 12.5px;
  transition: background .13s, color .13s;
}
.act-btn:hover { background: var(--panel-2); color: var(--text); }
.msg-meta { margin-left: 6px; font-size: 12px; color: var(--text-3); }

.err-box {
  display: flex; gap: 9px; align-items: flex-start;
  padding: 11px 13px;
  border-radius: 11px;
  background: rgba(229, 72, 77, .1);
  color: #c23b3f;
  font-size: 13.8px;
}
html[data-theme="dark"] .err-box { color: #ff8b8f; }
.err-box .err-retry { margin-left: auto; flex: none; }

.scroll-bottom-btn {
  position: absolute; left: 50%; transform: translateX(-50%);
  bottom: 132px; z-index: 20;
  width: 34px; height: 34px; border-radius: 50%;
  display: grid; place-items: center;
  border: 1px solid var(--border);
  background: var(--panel); color: var(--text-2);
  box-shadow: var(--shadow-sm);
}
.scroll-bottom-btn:hover { color: var(--accent); border-color: var(--accent); }

/* ==========================================================================
   输入区
   ========================================================================== */

.composer-wrap {
  flex: none;
  padding: 6px 20px 14px;
  position: relative; z-index: 10;
  background: linear-gradient(to top, var(--bg) 72%, transparent);
}
.composer {
  max-width: 820px; margin: 0 auto;
  border: 1px solid var(--border-strong);
  border-radius: 18px;
  background: var(--panel);
  box-shadow: var(--shadow-sm);
  padding: 8px 8px 8px 10px;
  transition: border-color .16s, box-shadow .16s;
}
.composer:focus-within { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.composer.dragover { border-color: var(--accent); background: var(--accent-soft); }

.attach-strip { display: flex; flex-wrap: wrap; gap: 8px; padding: 4px 2px 8px; }
.attach-item {
  position: relative;
  width: 66px; height: 66px;
  border-radius: 11px; overflow: hidden;
  border: 1px solid var(--border);
  background: var(--panel-2);
}
.attach-item img { width: 100%; height: 100%; object-fit: cover; display: block; }
.attach-item .rm {
  position: absolute; top: 3px; right: 3px;
  width: 19px; height: 19px; border-radius: 50%;
  display: grid; place-items: center;
  border: none; background: rgba(0, 0, 0, .58); color: #fff;
  font-size: 12px; line-height: 1;
}
.attach-item .rm:hover { background: rgba(229, 72, 77, .9); }
.attach-item .sz {
  position: absolute; left: 0; right: 0; bottom: 0;
  font-size: 10px; text-align: center; color: #fff;
  background: rgba(0, 0, 0, .5); padding: 1px 0;
}

#input {
  width: 100%;
  border: none; outline: none; resize: none;
  background: transparent;
  color: var(--text);
  font-size: 15px; line-height: 1.65;
  padding: 8px 6px 4px;
  max-height: 200px;
  overflow-y: auto;
}
#input::placeholder { color: var(--text-3); }

.composer-bar { display: flex; align-items: center; gap: 8px; padding: 2px 2px 0; }
.cb-left { display: flex; align-items: center; gap: 8px; }
.cb-right { margin-left: auto; }
.img-hint { font-size: 12px; color: var(--text-3); }

.send-btn {
  width: 36px; height: 36px; border-radius: 50%;
  display: grid; place-items: center;
  border: none;
  background: linear-gradient(135deg, #fb923c, #f97316);
  color: #fff;
  box-shadow: 0 2px 10px rgba(249, 115, 22, .32);
  transition: filter .15s, transform .12s, background .15s, box-shadow .15s;
}
.send-btn:hover:not(:disabled) { filter: brightness(1.06); }
.send-btn:active:not(:disabled) { transform: scale(.94); }
.send-btn:disabled { background: var(--panel-2); color: var(--text-3); box-shadow: none; cursor: not-allowed; }
.send-btn .ico-stop { display: none; }
.send-btn.generating { background: var(--text-2); box-shadow: none; }
.send-btn.generating:disabled { background: var(--text-2); color: var(--bg); cursor: pointer; opacity: 1; }
.send-btn.generating .ico-send { display: none; }
.send-btn.generating .ico-stop { display: block; }

.hint {
  max-width: 820px; margin: 8px auto 0;
  text-align: center; font-size: 12px; color: var(--text-3);
}

/* ==========================================================================
   灯箱 / 提示
   ========================================================================== */

.lightbox {
  position: fixed;
  top: 0; right: 0; bottom: 0; left: 0;
  z-index: 90;
  display: grid; place-items: center;
  background: var(--overlay);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
  padding: 34px;
  cursor: zoom-out;
}
.lightbox img { max-width: 100%; max-height: 100%; border-radius: 12px; box-shadow: var(--shadow); }

.toast-wrap {
  position: fixed; left: 50%; bottom: 30px; transform: translateX(-50%);
  z-index: 120;
  display: flex; flex-direction: column; gap: 8px; align-items: center;
  pointer-events: none;
}
.toast {
  max-width: 78vw;
  padding: 9px 15px;
  border-radius: 11px;
  background: rgba(24, 27, 34, .93);
  color: #fff; font-size: 13.5px;
  box-shadow: var(--shadow);
  animation: toastIn .2s var(--ease);
}
html[data-theme="dark"] .toast { background: rgba(245, 237, 228, .95); color: #1b1713; }
@keyframes toastIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

/* ==========================================================================
   响应式
   ========================================================================== */

@media (max-width: 820px) {
  .sidebar {
    position: fixed; top: 0; bottom: 0; left: 0; z-index: 70;
    margin-left: calc(var(--sidebar-w) * -1);
    box-shadow: var(--shadow);
  }
  body.sb-open .sidebar { margin-left: 0; }
  body.sb-open .sb-mask { display: block; }
  body.sb-hidden .sidebar { margin-left: calc(var(--sidebar-w) * -1); }

  .msg-list { padding: 16px 14px 20px; }
  .composer-wrap { padding: 6px 12px 10px; }
  .chat-title { display: none; }
  .welcome h1 { font-size: 22px; }
  .model-name { max-width: 120px; }
  .scroll-bottom-btn { bottom: 140px; }
  .msg-imgs img { width: 88px; height: 88px; }
  .main::before { width: 380px; margin-left: -190px; }
}

@media (max-width: 480px) {
  .chips { grid-template-columns: 1fr; }
  .hint { display: none; }
}