:root {
  --blue: #1163f4;
  --blue-deep: #094ccd;
  --navy: #101d39;
  --text: #24344e;
  --muted: #63738c;
  --border: #e1eaf6;
  --surface: #fff;
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", "Source Han Sans SC", system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: #fff;
  font-synthesis: none;
  -webkit-font-smoothing: antialiased;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 96px; }
body { margin: 0; min-width: 320px; }
a { color: inherit; text-decoration: none; }
button { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button:focus-visible, a:focus-visible { outline: 3px solid #5b98ff; outline-offset: 4px; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; top: -100px; left: 20px; padding: 12px 22px; z-index: 99; background: #fff; color: #135ae1; border-radius: 6px; }
.skip-link:focus { top: 10px; }

/* 视觉上对应封面顶部极简导航：只有名称与立即体验 */
.site-header { height: 76px; background: rgba(249,252,255,.96); border-bottom: 1px solid rgba(209,222,240,.56); position: relative; z-index: 10; }
.header-inner { max-width: 1660px; width: calc(100% - 10%); height: 100%; display: flex; align-items: center; justify-content: space-between; margin: auto; gap: 22px; }
.brand { display: inline-flex; min-width: 0; align-items: center; gap: 14px; color: #122247; font-size: clamp(15px, 1.4vw, 23px); font-weight: 800; letter-spacing: -.5px; }
.brand-mark { display: inline-flex; width: 45px; height: 45px; flex: 0 0 45px; color: #1462f4; }
.brand-mark svg { width: 100%; }
.brand-text { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.button { display: inline-flex; align-items: center; justify-content: center; gap: 13px; font-weight: 700; border-radius: 12px; border: 1px solid transparent; cursor: pointer; white-space: nowrap; transition: transform .2s ease, box-shadow .2s ease, background .2s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: #1162f4; color: white; box-shadow: 0 11px 25px rgba(22,91,226,.18); }
.button-primary:hover { background: #0653e5; box-shadow: 0 15px 28px rgba(22,91,226,.24); }
.button-header { padding: 11px 29px; min-width: 145px; font-size: 18px; border-radius: 11px; }
.button-large { min-height: 62px; min-width: 200px; padding: 0 26px; font-size: 19px; }
.button-large svg { width: 22px; height: 22px; fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round; }
.button-outline { background: rgba(255,255,255,.7); color: #143a7a; border-color: #bacde8; box-shadow: 0 10px 22px rgba(46,91,157,.06); }
.button-outline:hover { background: #fff; border-color: #75a5f8; }

/* 首屏：真实网页排版，不是单张封面背景图 */
.hero { isolation: isolate; position: relative; overflow: hidden; background: linear-gradient(110deg, #f8fbff 0%, #f1f8ff 39%, #dcefff 74%, #f5fbff 100%); }
.hero-glow { position: absolute; inset: 0; z-index: -2; background: radial-gradient(ellipse at 73% 25%, rgba(90,178,255,.22), transparent 47%), radial-gradient(ellipse at 10% 84%, rgba(241,249,255,.93), transparent 55%); }
.campus-scene { position: absolute; z-index: -1; width: 108%; height: 100%; object-fit: cover; inset: 0 0 0 auto; opacity: .86; pointer-events: none; }
.hero::after { content: ""; z-index: -1; position: absolute; bottom: 0; left: 0; width: 100%; height: 105px; background: linear-gradient(0deg,rgba(255,255,255,.88),transparent); }
.hero-inner { max-width: 1660px; min-height: 735px; width: calc(100% - 10%); margin: auto; display: grid; grid-template-columns: minmax(0, .98fr) minmax(0, 1.04fr); gap: 20px; align-items: center; position: relative; }
.hero-copy { position: relative; z-index: 2; padding: 34px 0 47px; }
.eyebrow { margin: 0 0 33px; font-size: 15px; letter-spacing: 2.1px; color: #6d81a1; display: flex; align-items: center; gap: 10px; }
.eyebrow-line { display: inline-block; width: 20px; height: 2px; background: #3778ed; }
h1, h2, h3, p { margin-top: 0; }
.hero h1 { font-size: clamp(39px, 4.15vw, 66px); line-height: 1.28; letter-spacing: -1.7px; color: #0d1b37; font-weight: 850; margin: 0; white-space: nowrap; }
.hero h1 span { display: block; color: #1166f4; letter-spacing: -2.8px; }
.hero-subtitle { margin: 16px 0 22px; font-size: clamp(18px, 1.58vw, 24px); color: #283e61; font-weight: 620; line-height: 1.65; }
.hero-description { max-width: 645px; margin-bottom: 31px; font-size: clamp(14px, 1.1vw, 17px); line-height: 2.03; letter-spacing: .06px; color: #62738f; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 18px; }
.feature-chips { display: grid; grid-template-columns: repeat(4,1fr); gap: 7px; margin-top: 28px; max-width: 650px; }
.feature-chip { display: flex; align-items: center; justify-content: center; gap: 8px; border: 1px solid rgba(221,232,248,.9); background: rgba(255,255,255,.83); border-radius: 12px; padding: 12px 9px; color: #4a5973; font-size: clamp(11px, .92vw, 13px); line-height: 1.5; box-shadow: 0 9px 23px rgba(45,91,153,.05); transition: transform .2s, border-color .2s; }
.feature-chip:hover { transform: translateY(-4px); border-color: #9fc1fd; }
.chip-icon { display: inline-flex; width: 31px; height: 31px; flex: 0 0 31px; color: #1268f6; }
.chip-icon svg { width: 100%; height: 100%; }

/* 用真正的 HTML/CSS 重绘电脑中的真实聊天系统界面；文字不会被固化在图片中 */
.hero-visual { min-width: 0; position: relative; z-index: 1; align-self: end; margin: 0 -28px 35px -3px; }
.laptop-wrap { position: relative; width: 100%; max-width: 880px; margin: 0 auto; padding-top: 20px; filter: drop-shadow(0 20px 25px rgba(41,72,114,.17)); }
.laptop-screen { background: #f6f8fc; border: 13px solid #171f2c; border-bottom-width: 17px; border-radius: 20px 20px 8px 8px; width: 100%; aspect-ratio: 1.64; min-height: 370px; overflow: hidden; box-shadow: 0 3px 2px #6e7479 inset, 0 0 0 2px #747c87, 0 12px 36px rgba(42,54,70,.12); position: relative; }
.app-topline { height: 37px; padding: 0 14px; display: flex; align-items: center; gap: 12px; font-size: 9px; background: #fafbfd; border-bottom: 1px solid #eef2fa; color: #8a98ac; }
.window-dots { display: inline-flex; align-items: center; gap: 5px; flex: 0 0 auto; }
.window-dots i { width: 8px; height: 8px; border-radius: 50%; background: #fa655c; }
.window-dots i:nth-child(2) { background: #f8c44b; }
.window-dots i:nth-child(3) { background: #45bb62; }
.app-url { opacity: .56; font-size: 8px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; flex: 1; text-align: center; }
.app-toplinks { color: #2172f3; white-space: nowrap; font-size: 9px; }
.app-layout { height: calc(100% - 37px); display: grid; grid-template-columns: 22% minmax(0,1fr); }
.app-sidebar { min-width: 0; display: flex; flex-direction: column; background: #e8ebf2; color: #4e5d76; padding: 17px 11px 9px; border-right: 1px solid #e4e9f2; }
.app-sidebar-title { display: flex; gap: 7px; font-weight: 800; color: #2f3c57; font-size: 9px; line-height: 1.5; align-items: center; margin-bottom: 20px; white-space: nowrap; overflow: hidden; }
.app-avatar-mini { display: grid; place-items: center; border: 1px solid #dde7f5; border-radius: 7px; background: #fff; color: #2168ef; font-size: 18px; width: 27px; height: 27px; flex: 0 0 27px; }
.app-new { display: block; border: 1px solid #e0e4ef; background: #fff; color: #145ff6; padding: 9px 3px; border-radius: 7px; font-size: 11px; font-weight: 700; cursor: pointer; box-shadow: 0 2px 4px rgba(18,36,76,.04); }
.app-new:hover { background: #f3f8ff; }
.app-navitem { color: #697891; font-size: 10px; display: flex; align-items: center; gap: 7px; margin-top: 14px; padding: 9px 9px; white-space: nowrap; border-radius: 8px; }
.app-navitem.active { color: #1359e6; background: #d6def8; font-weight: 700; }
.app-navitem span { font-size: 13px; }
.app-sidebar-bottom { margin-top: auto; color: #9099ae; font-size: 8px; white-space: nowrap; }
.app-sidebar-bottom span { margin-right: 10px; }
.app-sidebar-bottom b { color: #1e60da; font-size: 13px; }
.app-main { position: relative; min-width: 0; padding: 28px 6.4% 56px; background: #fff; overflow: hidden; }
.assistant-avatar { width: 38px; height: 38px; margin: 0 auto 14px; background: white; border-radius: 12px; box-shadow: 0 4px 14px #dae5f677; display: grid; place-items: center; }
.assistant-avatar svg { width: 34px; height: 34px; }
.chat-message { max-width: 475px; margin: 0 auto; color: #536078; font-size: clamp(7px, .65vw, 10px); line-height: 1.72; }
.chat-message h2 { font-size: clamp(8px, .75vw, 11px); color: #34425d; margin-bottom: 4px; font-weight: 750; }
.chat-message .chat-lead { margin-bottom: 9px; }
.chat-rule { background: #acb7c8; height: 1px; width: 100%; margin: 9px 0; }
.chat-message h3 { font-size: clamp(8px, .8vw, 12px); font-weight: 750; color: #35425e; margin: 0 0 3px; }
.chat-message p { margin: 0 0 4px; }
.chat-message p.chat-role { color: #5373ae; font-size: .92em; margin-bottom: 4px; }
.preview-input { position: absolute; left: 5%; right: 5%; bottom: 13px; height: 42px; background: #fff; display: flex; align-items: center; gap: 12px; border: 1px solid #e9eff9; border-radius: 11px; box-shadow: 0 3px 10px rgba(55,79,131,.10); padding: 5px 6px 5px 15px; font-size: 9px; color: #a0afc5; }
.preview-input > span:first-child { flex: 1; overflow: hidden; white-space: nowrap; text-overflow: ellipsis; }
.paperclip { font-size: 17px; color: #72839b; }
.preview-input button { border: 0; border-radius: 8px; background: #1164f4; color: white; width: 31px; height: 29px; cursor: pointer; display: grid; place-items: center; }
.preview-input button svg { width: 18px; height: 18px; }
.laptop-hinge { width: 12%; height: 4px; margin: 0 auto; background: #394657; border-radius: 0 0 4px 4px; }
.laptop-base { position: relative; margin: 0 -5%; width: 110%; height: 24px; background: linear-gradient(#dde3e8 0%,#b7bec8 38%,#f5f8fb 70%,#8f9aa5 100%); border-radius: 0 0 42% 42% / 0 0 85% 85%; box-shadow: 0 4px 1px #69727d66; }
.laptop-base span { display: block; margin: 0 auto; width: 16%; height: 7px; background: #9ea9b5; border-radius: 0 0 16px 16px; }
.laptop-shadow { position: absolute; left: 8%; right: 8%; bottom: -11px; height: 17px; background: #52627c; filter: blur(17px); opacity: .33; border-radius: 50%; z-index: -1; }
.hero-bottom-tint { position: absolute; right: 0; bottom: 0; left: 0; height: 4px; background: linear-gradient(to right, transparent, #c6e2ff55, transparent); }

/* 首页下方的官网介绍模块 */
.section { padding: 95px 5%; }
.section-heading { max-width: 770px; margin: 0 auto 40px; text-align: center; }
.section-kicker { margin-bottom: 13px; color: #2368dc; font-size: 12px; letter-spacing: 3px; font-weight: 800; }
.section-heading h2, .roles-overview h2 { font-size: clamp(28px, 2.5vw, 40px); line-height: 1.4; margin-bottom: 14px; color: #14213c; }
.section-heading > p:last-child { color: #78869b; font-size: 16px; line-height: 1.8; }
.content-grid { max-width: 1320px; margin: auto; display: grid; grid-template-columns: repeat(4,minmax(0,1fr)); gap: 21px; }
.content-card { position: relative; border-radius: 19px; background: white; border: 1px solid #e3ebf6; padding: 29px 24px 24px; min-height: 315px; box-shadow: 0 12px 38px rgba(43,83,145,.045); scroll-margin-top: 100px; transition: transform .2s, box-shadow .2s; }
.content-card:hover { transform: translateY(-5px); box-shadow: 0 20px 46px rgba(43,83,145,.10); }
.card-index { position: absolute; top: 26px; right: 25px; color: #e4ebf7; font-size: 27px; font-weight: 800; }
.card-icon { display: grid; place-items: center; width: 55px; height: 55px; border-radius: 15px; font-size: 32px; font-weight: 700; margin-bottom: 27px; }
.card-icon.blue { background: #eaf2ff; color: #1767ec; }
.card-icon.cyan { background: #e8f9fd; color: #13a5c9; }
.card-icon.violet { background: #f0ebfe; color: #7b65d9; }
.card-icon.teal { background: #e8f8f4; color: #20a990; }
.content-card h3 { font-size: 19px; color: #1c2d4a; margin-bottom: 13px; }
.content-card > p { color: #6e7c91; font-size: 14px; line-height: 1.85; margin-bottom: 23px; }
.card-foot { color: #4780d7; border-top: 1px solid #eaf0f8; font-size: 12px; padding-top: 16px; }
.section-roles { background: #f5f9ff; }
.roles-inner { max-width: 1290px; display: grid; grid-template-columns: .85fr 1.15fr; gap: 95px; margin: auto; align-items: center; }
.roles-overview h2 { margin-bottom: 22px; }
.roles-overview > p:not(.section-kicker) { color: #6e7f99; font-size: 16px; line-height: 2.0; max-width: 470px; }
.text-link { display: inline-flex; gap: 10px; margin-top: 19px; align-items: center; color: #1462e5; font-weight: 700; }
.text-link span { font-size: 21px; }
.role-panel { background: #fff; border: 1px solid #e2ebf8; border-radius: 21px; box-shadow: 0 18px 46px rgba(43,76,132,.06); padding: 25px; }
.role-tabs { display: flex; gap: 9px; padding-bottom: 19px; border-bottom: 1px solid #e7edf7; }
.role-tab { border: 0; background: #f2f6fc; color: #63738e; cursor: pointer; padding: 11px 25px; border-radius: 9px; font-size: 15px; }
.role-tab:hover { background: #e8f0ff; }
.role-tab.is-active { background: #1164f4; color: white; box-shadow: 0 6px 18px #1164f433; }
.role-detail { padding: 24px 4px 7px; }
.role-badge { color: #2473eb; font-size: 12px; letter-spacing: 2px; font-weight: 800; }
.role-detail h3 { font-size: 24px; margin: 12px 0; color: #192942; }
.role-detail > p { color: #6c7c94; font-size: 15px; line-height: 1.85; }
.role-example { margin-top: 20px; background: #f3f7fd; padding: 19px; border-radius: 11px; }
.role-example small { color: #2365cc; font-weight: 700; }
.role-example p { color: #566a87; margin: 10px 0 0; font-size: 14px; line-height: 1.85; }
.section-flow { padding-bottom: 75px; }
.steps { max-width: 1190px; margin: 57px auto 85px; display: grid; grid-template-columns: 1fr 40px 1fr 40px 1fr; gap: 10px; align-items: center; }
.steps article { text-align: center; padding: 20px 18px; }
.steps article span { display: grid; place-items: center; width: 54px; height: 54px; border-radius: 50%; margin: 0 auto 20px; background: #eaf2ff; color: #2069de; font-weight: 800; }
.steps h3 { color: #1c2e4b; font-size: 20px; }
.steps p { color: #728097; font-size: 14px; line-height: 1.9; }
.step-arrow { color: #a2b6d6; font-size: 30px; text-align: center; margin-top: -55px; }
.bottom-cta { max-width: 1320px; padding: 37px 49px; margin: auto; border-radius: 20px; background: linear-gradient(100deg,#1053d6,#1c82ef); color: white; display: flex; justify-content: space-between; gap: 25px; align-items: center; }
.bottom-cta h2 { font-size: 25px; margin-bottom: 9px; }
.bottom-cta p { margin-bottom: 0; color: #d6e8ff; }
.button-light { padding: 15px 29px; background: white; color: #145dde; flex: 0 0 auto; }
.site-footer { border-top: 1px solid #e5ebf5; background: #fafcff; display: flex; justify-content: space-between; align-items: center; gap: 30px; padding: 30px 5%; color: #8090a6; font-size: 13px; }
.site-footer > div { display: flex; flex-wrap: wrap; gap: 14px 28px; }
.footer-brand { color: #38547b; font-weight: 700; }
.site-footer a { white-space: nowrap; color: #2769cd; }

@media (max-width: 1350px) {
  .hero-inner, .header-inner { width: calc(100% - 7%); }
  .hero-inner { gap: 6px; }
  .hero h1 { font-size: clamp(36px, 4vw, 55px); }
  .hero-description { font-size: 14px; }
  .hero-subtitle { font-size: 18px; }
  .hero-visual { margin-right: -15px; margin-left: 0; }
  .feature-chip { gap: 5px; padding: 11px 4px; font-size: 11px; }
  .chip-icon { width: 27px; flex-basis: 27px; height: 27px; }
  .laptop-screen { min-height: 300px; }
  .chat-message { font-size: 8px; }
}
@media (max-width: 1060px) {
  .site-header { height: 68px; }
  .header-inner, .hero-inner { width: calc(100% - 10%); }
  .hero-inner { padding: 55px 0 65px; grid-template-columns: 1fr; min-height: unset; }
  .hero-copy { padding: 0; }
  .hero h1 { font-size: clamp(38px, 5.8vw, 61px); }
  .hero-description { font-size: 16px; max-width: 750px; }
  .hero-subtitle { font-size: 21px; }
  .feature-chip { font-size: 13px; }
  .hero-visual { max-width: 860px; width: 95%; margin: 25px auto 0; }
  .laptop-screen { min-height: 360px; }
  .chat-message { font-size: 10px; }
  .content-grid { grid-template-columns: repeat(2,minmax(0,1fr)); }
  .content-card { min-height: 285px; }
  .roles-inner { gap: 35px; }
}
@media (max-width: 650px) {
  html { scroll-padding-top: 65px; }
  .site-header { height: 64px; }
  .header-inner { width: calc(100% - 30px); gap: 9px; }
  .brand { gap: 7px; font-size: 12px; letter-spacing: -.4px; }
  .brand-mark { width: 32px; height: 32px; flex-basis: 32px; }
  .button-header { font-size: 13px; min-width: 81px; padding: 10px 12px; border-radius: 9px; }
  .hero-inner { width: calc(100% - 36px); padding: 42px 0 55px; }
  .eyebrow { font-size: 11px; letter-spacing: 1.3px; margin-bottom: 20px; }
  .hero h1 { font-size: clamp(30px, 7.7vw, 42px); line-height: 1.38; letter-spacing: -1.5px; }
  .hero h1 span { letter-spacing: -2px; }
  .hero-subtitle { font-size: 17px; line-height: 1.6; margin: 20px 0 14px; }
  .hero-description { font-size: 13.5px; line-height: 1.85; margin-bottom: 23px; }
  .hero-actions { gap: 10px; }
  .button-large { min-width: 0; flex: 1; min-height: 49px; padding: 0 10px; font-size: 15px; }
  .button-large svg { width: 18px; }
  .feature-chips { grid-template-columns: repeat(2,minmax(0,1fr)); gap: 9px; margin-top: 24px; }
  .feature-chip { justify-content: flex-start; font-size: 12px; padding: 10px 11px; }
  .hero-visual { width: 100%; margin-top: 24px; }
  .laptop-wrap { padding-top: 8px; }
  .laptop-screen { border-width: 7px; border-bottom-width: 9px; border-radius: 12px 12px 6px 6px; min-height: 245px; aspect-ratio: 1.38; }
  .app-topline { height: 24px; padding: 0 6px; gap: 5px; }
  .app-toplinks { display: none; }
  .window-dots { gap: 3px; }
  .window-dots i { width: 5px; height: 5px; }
  .app-layout { height: calc(100% - 24px); grid-template-columns: 25% minmax(0,1fr); }
  .app-sidebar { padding: 10px 5px 5px; }
  .app-sidebar-title { font-size: 6px; gap: 4px; margin-bottom: 12px; }
  .app-avatar-mini { width: 16px; height: 16px; flex-basis: 16px; font-size: 10px; border-radius: 4px; }
  .app-new { font-size: 7px; padding: 6px 2px; border-radius: 4px; }
  .app-navitem { margin-top: 6px; padding: 5px 4px; font-size: 7px; gap: 3px; }
  .app-navitem span { font-size: 8px; }
  .app-sidebar-bottom { font-size: 5px; }
  .app-sidebar-bottom span { display: none; }
  .app-sidebar-bottom b { font-size: 8px; }
  .app-main { padding: 12px 5.5% 39px; }
  .assistant-avatar { width: 23px; height: 23px; margin-bottom: 7px; }
  .assistant-avatar svg { width: 20px; height: 20px; }
  .chat-message { font-size: 7px; line-height: 1.52; }
  .chat-message h2 { font-size: 7px; }
  .chat-message h3 { font-size: 7px; }
  .chat-rule { margin: 5px 0; }
  .chat-message p { margin-bottom: 2px; }
  .preview-input { height: 26px; bottom: 7px; padding: 3px 3px 3px 7px; font-size: 7px; border-radius: 7px; }
  .preview-input button { width: 18px; height: 18px; border-radius: 4px; }
  .preview-input button svg { width: 12px; height: 12px; }
  .paperclip { display: none; }
  .laptop-base { height: 12px; }
  .preview-label { font-size: 9px; margin-top: 16px; }
  .section { padding: 65px 18px; }
  .section-heading { margin-bottom: 27px; }
  .section-heading h2, .roles-overview h2 { font-size: 26px; }
  .section-heading > p:last-child { font-size: 13px; }
  .content-grid { grid-template-columns: 1fr; gap: 13px; }
  .content-card { min-height: unset; padding: 21px; }
  .card-icon { width: 45px; height: 45px; font-size: 26px; margin-bottom: 16px; }
  .content-card h3 { font-size: 18px; }
  .content-card > p { margin-bottom: 15px; }
  .roles-inner { grid-template-columns: 1fr; gap: 22px; }
  .roles-overview > p:not(.section-kicker) { font-size: 14px; }
  .role-panel { padding: 15px; }
  .role-tabs { gap: 6px; padding-bottom: 12px; }
  .role-tab { flex: 1; padding: 10px 0; font-size: 13px; }
  .role-detail h3 { font-size: 19px; }
  .steps { grid-template-columns: 1fr; gap: 3px; margin: 30px auto 47px; }
  .steps article { padding: 8px 13px; }
  .steps article span { width: 44px; height: 44px; margin-bottom: 12px; }
  .steps h3 { margin-bottom: 8px; }
  .steps p { margin-bottom: 0; }
  .step-arrow { margin: 0; font-size: 20px; transform: rotate(90deg); }
  .bottom-cta { padding: 25px; flex-direction: column; text-align: center; }
  .bottom-cta h2 { font-size: 22px; }
  .bottom-cta p { font-size: 14px; line-height: 1.7; }
  .site-footer { padding: 24px 18px; gap: 20px; align-items: flex-start; }
  .site-footer > div { gap: 8px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *,*::before,*::after { transition-duration: .01ms !important; } }