/* ============================================================
   爱汇创 AiConvg 企业官网 —— 全站样式（小米官网风格 · mobile-first）
   设计语言：方正无圆角 / 橙色点缀(#ff6700) / 白底灰瓦产品网格 /
             顶部深色工具条 + 搜索 / 左侧分类栏 + 大图 banner / 浅色多栏页脚
   ============================================================ */

:root {
  --brand: #ff6700;        /* 小米橙 */
  --brand-d: #e65400;
  --price: #ff5000;        /* 价格橙 */
  --ink: #333;
  --ink-2: #61666d;
  --muted: #b0b0b0;
  --line: #e0e0e0;
  --line-2: #d7d7d7;
  --tile: #f7f7f7;         /* 产品瓦片灰 */
  --tile-2: #fafafa;
  --top: #424242;          /* 顶部深色条 */
  --top-t: #b0b0b0;
  --bg: #fff;
  --max: 1226px;           /* 小米容器宽度 */
  --radius: 0;             /* 方正：几乎不用圆角 */
  --shadow: 0 6px 18px rgba(0, 0, 0, .08);
  --shadow-lg: 0 12px 30px rgba(0, 0, 0, .12);
  --header-h: 80px;
  --topbar-h: 40px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--ink);
  font-family: "MiSans", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
    system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  font-size: 14px; line-height: 1.6;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4 { margin: 0; font-weight: 500; line-height: 1.3; }
p { margin: 0 0 1em; }

.container { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 16px; }
.text-brand { color: var(--brand); }

/* ---------- Buttons (小米方角) ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  padding: 8px 24px; border-radius: 0; font-weight: 500; font-size: 14px; cursor: pointer;
  border: 1px solid transparent; transition: .2s; white-space: nowrap;
}
.btn--primary { background: var(--brand); color: #fff; }
.btn--primary:hover { background: var(--brand-d); }
.btn--ghost { background: transparent; color: var(--ink); border-color: var(--line-2); }
.btn--ghost:hover { color: var(--brand); border-color: var(--brand); }
.btn--sm { padding: 5px 14px; font-size: 13px; }

/* ---------- Top utility bar (深色) ---------- */
.topbar { background: var(--top); color: var(--top-t); font-size: 12px; height: var(--topbar-h); display: flex; align-items: center; }
.topbar .container { display: flex; align-items: center; justify-content: space-between; }
.topbar__left { display: flex; align-items: center; gap: 4px; overflow: hidden; }
.topbar a { color: var(--top-t); padding: 0 6px; line-height: 18px; }
.topbar a:hover { color: #fff; }
.topbar .sep { color: #616161; }
.topbar__right { display: flex; align-items: center; }

/* ---------- Header / Main nav (白底) ---------- */
.header { background: #fff; position: sticky; top: 0; z-index: 100; box-shadow: 0 2px 4px rgba(0,0,0,.04); }
.header::after { content: ""; display: block; height: 2px; background: linear-gradient(90deg, var(--brand), #ffb27a); transform: scaleX(0); transition: transform .3s; }
.header.is-scrolled::after { transform: scaleX(1); }
.nav { display: flex; align-items: center; height: var(--header-h); gap: 24px; }
.brand { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.brand__logo {
  width: 54px; height: 54px; display: block; flex-shrink: 0;
  filter: drop-shadow(0 2px 6px rgba(255,103,0,.32));
}
.brand__txt b { display: block; font-size: 18px; font-weight: 700; color: var(--ink); line-height: 1.1; }
.brand__txt small { display: block; font-size: 11px; color: var(--muted); font-weight: 400; }

.nav__menu { display: flex; align-items: center; gap: 4px; height: 100%; }
.nav__menu a {
  position: relative; height: 100%; display: inline-flex; align-items: center; padding: 0 14px;
  font-size: 16px; color: var(--ink); transition: .2s;
}
.nav__menu a::after { content: ""; position: absolute; left: 14px; right: 14px; bottom: 0; height: 2px; background: var(--brand); transform: scaleX(0); transition: .25s; }
.nav__menu a:hover { color: var(--brand); }
.nav__menu a:hover::after, .nav__menu a.is-active::after { transform: scaleX(1); }
.nav__menu a.is-active { color: var(--brand); }

.nav__search { margin-left: auto; display: flex; align-items: center; border: 1px solid var(--line-2); height: 38px; }
.nav__search input { border: 0; outline: none; width: 180px; padding: 0 12px; font: inherit; color: var(--ink); }
.nav__search button { border: 0; background: var(--tile); color: var(--ink-2); width: 46px; height: 100%; cursor: pointer; font-size: 16px; }
.nav__search button:hover { background: var(--brand); color: #fff; }
.nav__cart { position: relative; margin-left: 18px; color: var(--ink-2); font-size: 13px; text-align: center; }
.nav__cart .ic { font-size: 22px; display: block; }
.nav__cart:hover { color: var(--brand); }
.nav__toggle { display: none; width: 44px; height: 44px; border: 1px solid var(--line); background: #fff; cursor: pointer; flex-direction: column; gap: 5px; align-items: center; justify-content: center; margin-left: auto; }
.nav__toggle span { width: 20px; height: 2px; background: var(--ink); }

/* ---------- Section scaffold ---------- */
.section { padding: 44px 0; }
.section--tile { background: var(--tile-2); }
.sec-head { display: flex; align-items: baseline; justify-content: center; gap: 12px; margin-bottom: 24px; }
.sec-head h2 { font-size: 26px; color: var(--ink); font-weight: 500; }
.sec-head .tabs { display: flex; gap: 4px; justify-content: center; flex-wrap: wrap; margin-bottom: 26px; }
.sec-head .tabs a { padding: 4px 14px; color: var(--muted); font-size: 15px; }
.sec-head .tabs a:hover, .sec-head .tabs a.is-active { color: var(--brand); }
.section-sub { text-align: center; color: var(--muted); margin-top: -14px; margin-bottom: 26px; }

/* ---------- Hero (左分类栏 + 大 banner) ---------- */
.hero { padding: 20px 0 8px; }
.hero .container { display: grid; grid-template-columns: 234px 1fr; gap: 24px; align-items: stretch; }
.catbar { background: #f0f0f0; }
.catbar li a {
  display: flex; align-items: center; justify-content: space-between; height: 41px; padding: 0 16px;
  color: var(--ink-2); font-size: 14px; transition: .15s;
}
.catbar li a:hover { background: #fff; color: var(--brand); }
.catbar li a .arw { color: var(--muted); }
.banner {
  position: relative; overflow: hidden; background: linear-gradient(120deg, #ff8a3d, var(--brand) 55%, #e65400);
  color: #fff; display: flex; align-items: center; min-height: 360px;
}
.banner__inner { padding: 48px; max-width: 60%; position: relative; z-index: 2; }
.banner__eyebrow { font-size: 14px; opacity: .9; letter-spacing: 2px; }
.banner h1 { font-size: 40px; font-weight: 700; margin: 10px 0 12px; line-height: 1.15; }
.banner p { font-size: 16px; opacity: .95; max-width: 380px; margin-bottom: 24px; }
.banner .btn--ghost { color: #fff; border-color: rgba(255,255,255,.6); }
.banner .btn--ghost:hover { background: #fff; color: var(--brand); border-color: #fff; }
.banner__deco { position: absolute; right: 40px; top: 50%; transform: translateY(-50%); z-index: 1; }
.banner__dots { position: absolute; bottom: 18px; left: 0; right: 0; display: flex; gap: 8px; justify-content: center; z-index: 3; }
.banner__dots i { width: 8px; height: 8px; border-radius: 50%; background: rgba(255,255,255,.5); cursor: pointer; }
.banner__dots i.on { background: #fff; width: 20px; border-radius: 4px; }
/* phone mock */
.phone { width: 190px; height: 340px; background: #fff; border-radius: 22px; box-shadow: 0 18px 40px rgba(0,0,0,.25); padding: 10px; }
.phone__screen { width: 100%; height: 100%; border-radius: 14px; background: linear-gradient(160deg,#fff3ea,#ffe0cc); display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 8px; color: var(--brand); }
.phone__screen .em { font-size: 46px; }
.phone__screen b { font-size: 15px; color: #333; font-weight: 600; }
.phone__screen span { font-size: 12px; color: #888; }

/* ---------- Product grid (小米 热卖瓦片) ---------- */
.grid { display: grid; gap: 14px; }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }
.grid--2 { grid-template-columns: repeat(2, 1fr); }

.tile {
  background: #fff; padding: 24px 20px 22px; text-align: center; transition: .2s;
  border: 1px solid transparent; display: flex; flex-direction: column;
}
.tile:hover { box-shadow: var(--shadow-lg); z-index: 2; position: relative; }
.tile__img {
  height: 150px; margin-bottom: 18px; display: grid; place-items: center; background: var(--tile);
  border-radius: 4px;
}
.tile__img .em { font-size: 58px; line-height: 1; }
.tile__img img { width: 100%; height: 100%; object-fit: cover; object-position: top center; border-radius: 4px; background: #fff; }
.tile h3 { font-size: 15px; color: var(--ink); font-weight: 500; margin-bottom: 6px; }
.tile__desc { font-size: 12px; color: var(--muted); height: 18px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; margin-bottom: 12px; }
.tile__price { color: var(--price); font-size: 16px; }
.tile__price small { font-size: 12px; }
.tile__price .old { color: var(--muted); font-size: 12px; text-decoration: line-through; margin-left: 6px; }
.tile__tag { display: inline-block; font-size: 11px; color: #fff; background: var(--brand); padding: 1px 6px; margin-bottom: 8px; }
.tile__tag.gray { background: var(--muted); }
.tile__cta { margin-top: auto; padding-top: 14px; font-size: 13px; color: var(--brand); }
.tile__cta .go { display: inline-block; transition: .2s; }
.tile:hover .tile__cta .go { transform: translateX(4px); }
.tile--list { text-align: left; flex-direction: row; align-items: center; gap: 18px; padding: 28px; }
.tile--list .tile__img { width: 120px; height: 96px; margin: 0; flex-shrink: 0; }
.tile--list .tile__img .em { font-size: 44px; }
.tile--list h3 { font-size: 20px; }
.tile--list .tile__desc { white-space: normal; height: auto; }

/* ---------- Flagship (AI 视听工坊) ---------- */
.flag { background: linear-gradient(180deg,#fff4ec,#fff); }
.flag__head { text-align: center; max-width: 720px; margin: 0 auto 34px; }
.flag__head .badge { display:inline-block; background:var(--brand); color:#fff; font-size:12px; padding:3px 12px; margin-bottom:12px; }
.flag__head h2 { font-size: 32px; }
.flag__head p { color: var(--ink-2); }
.hl-strip { display:grid; grid-template-columns:repeat(4,1fr); gap:14px; margin:26px 0 34px; }
.hl { background:#fff; border:1px solid var(--line); text-align:center; padding:18px 10px; }
.hl b { display:block; font-size:26px; color:var(--brand); font-weight:600; }
.hl span { font-size:13px; color:var(--muted); }
.cap-grid { display:grid; grid-template-columns:repeat(3,1fr); gap:18px; }
.cap-card { background:#fff; border:1px solid var(--line); overflow:hidden; transition:.2s; display:flex; flex-direction:column; }
.cap-card:hover { box-shadow:var(--shadow-lg); border-color:#fff; }
.cap-card .cap-img { height:180px; background:var(--tile); overflow:hidden; border-bottom:1px solid var(--line); }
.cap-card .cap-img img { width:100%; height:100%; object-fit:cover; object-position:top center; display:block; }
.cap-card .cap-body { padding:18px 20px 22px; }
.cap-card .cap-body .em { font-size:22px; }
.cap-card h3 { font-size:17px; margin:4px 0 6px; }
.cap-card p { color:var(--ink-2); font-size:13.5px; margin:0; }
.cap-card .cap-feat { margin-top:10px; display:flex; flex-wrap:wrap; gap:6px; }
.cap-card .cap-feat i { font-style:normal; font-size:12px; color:var(--brand); background:#fff1e8; padding:2px 8px; }
/* browser frame mock */
.browser { background:#fff; border:1px solid var(--line-2); box-shadow:var(--shadow-lg); width:100%; }
.browser__bar { height:30px; background:#f0f0f0; border-bottom:1px solid var(--line); display:flex; align-items:center; gap:6px; padding:0 12px; }
.browser__bar i { width:10px; height:10px; border-radius:50%; background:#d5d5d5; display:inline-block; }
.browser__bar .url { margin-left:10px; font-size:11px; color:var(--muted); background:#fff; border:1px solid var(--line); padding:2px 10px; border-radius:10px; }
.browser img { width:100%; display:block; }

/* ---------- Secondary products ---------- */
.mini-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:14px; }
.mini { background:#fff; border:1px solid var(--line); padding:20px; transition:.2s; display:flex; gap:14px; align-items:flex-start; }
.mini:hover { box-shadow:var(--shadow); }
.mini .em { font-size:26px; flex-shrink:0; }
.mini h3 { font-size:15px; margin-bottom:4px; }
.mini p { font-size:12.5px; color:var(--muted); margin:0; }
.mini a { color:var(--brand); font-size:13px; }

/* ---------- Feature cards (通用) ---------- */
.card { background: #fff; border: 1px solid var(--line); padding: 28px; transition: .2s; height: 100%; }
.card:hover { box-shadow: var(--shadow); border-color: #fff; }
.card__icon { width: 56px; height: 56px; display: grid; place-items: center; font-size: 26px; margin-bottom: 16px; background: #fff1e8; color: var(--brand); border-radius: 4px; }
.card h3 { font-size: 18px; margin-bottom: 8px; }
.card p { color: var(--ink-2); margin: 0; font-size: 14px; }
.card__link { display: inline-block; margin-top: 14px; font-weight: 500; color: var(--brand); font-size: 14px; }
.card__link:hover { text-decoration: underline; }
.check-list li { position: relative; padding-left: 24px; margin-bottom: 10px; color: var(--ink-2); }
.check-list li::before { content: "✓"; position: absolute; left: 0; top: 0; color: var(--brand); font-weight: 700; }

/* ---------- Steps ---------- */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.step { background: #fff; border: 1px solid var(--line); padding: 26px 22px; transition: .2s; }
.step:hover { box-shadow: var(--shadow); }
.step b { display: block; font-size: 30px; color: var(--brand); font-weight: 300; margin-bottom: 10px; }
.step h4 { font-size: 16px; margin-bottom: 6px; }
.step p { margin: 0; color: var(--muted); font-size: 13px; }

/* ---------- Promo band ---------- */
.promo { background: linear-gradient(120deg,#ff8a3d,var(--brand)); color: #fff; text-align: center; padding: 52px 24px; }
.promo h2 { color: #fff; font-size: 28px; margin-bottom: 12px; }
.promo p { opacity: .95; margin-bottom: 22px; }
.promo .btn--ghost { color: #fff; border-color: rgba(255,255,255,.7); }
.promo .btn--ghost:hover { background: #fff; color: var(--brand); border-color: #fff; }

/* ---------- Feature split (inner) ---------- */
.feature { display: grid; gap: 40px; align-items: center; }
.feature__media { background: var(--tile); border-radius: 4px; }
.feature__media .shot { aspect-ratio: 16/10; display: grid; place-items: center; color: var(--muted); font-size: 15px; }

/* ---------- Page hero (内页顶部) ---------- */
.page-hero { background: var(--tile-2); border-bottom: 1px solid var(--line); padding: 34px 0; }
.page-hero h1 { font-size: 30px; }
.page-hero p { color: var(--ink-2); margin: 8px 0 0; max-width: 680px; }
.breadcrumb { font-size: 12px; color: var(--muted); margin-bottom: 10px; }
.breadcrumb a:hover { color: var(--brand); }

/* ---------- Forms ---------- */
.form-grid { display: grid; gap: 16px; }
.field label { display: block; font-weight: 500; font-size: 14px; margin-bottom: 6px; color: var(--ink); }
.field input, .field textarea, .field select {
  width: 100%; padding: 10px 12px; border: 1px solid var(--line-2); border-radius: 0;
  font: inherit; color: var(--ink); background: #fff; transition: .2s;
}
.field input:focus, .field textarea:focus, .field select:focus { outline: none; border-color: var(--brand); box-shadow: 0 0 0 2px rgba(255,103,0,.12); }
.field textarea { min-height: 130px; resize: vertical; }
.form-note { font-size: 12px; color: var(--muted); }
.contact-info { display: grid; gap: 12px; }
.info-item { display: flex; gap: 14px; align-items: flex-start; padding: 18px; border: 1px solid var(--line); background: #fff; }
.info-item .ic { width: 42px; height: 42px; background: #fff1e8; color: var(--brand); display: grid; place-items: center; font-size: 18px; flex-shrink: 0; }
.info-item b { display: block; }
.info-item span { color: var(--ink-2); }

/* ---------- Prose ---------- */
.prose { max-width: 820px; }
.prose h2 { margin-top: 30px; font-size: 20px; }
.prose p, .prose li { color: var(--ink-2); }
.prose ul { list-style: disc; padding-left: 22px; }
.prose ul li { margin-bottom: 8px; }

/* ---------- Footer (小米浅色多栏) ---------- */
.footer { background: #fff; color: #757575; font-size: 14px; }
.footer__service { border-bottom: 1px solid var(--line); }
.footer__service .row { display: flex; justify-content: space-around; text-align: center; padding: 24px 0; }
.footer__service .it { color: var(--ink-2); }
.footer__service .it .ic { font-size: 24px; display: block; margin-bottom: 4px; color: var(--brand); }
.footer__cols { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr 1.4fr; gap: 24px; padding: 40px 0 24px; }
.footer h4 { color: var(--ink); font-size: 14px; margin-bottom: 16px; font-weight: 500; }
.footer a { color: #757575; display: block; padding: 4px 0; }
.footer a:hover { color: var(--brand); }
.footer .brand { margin-bottom: 14px; }
.footer__desc { color: var(--muted); font-size: 13px; max-width: 280px; }
.footer__bottom { border-top: 1px solid var(--line); padding: 20px 0; display: flex; flex-wrap: wrap; gap: 8px 18px; justify-content: space-between; color: var(--muted); font-size: 12px; }
.footer__bottom a { display: inline; }

/* ---------- Reveal ---------- */
.reveal { opacity: 0; transform: translateY(18px); transition: .6s ease; }
.reveal.is-in { opacity: 1; transform: none; }

/* ---------- Inner-page helpers (小米风兼容) ---------- */
.eyebrow { display: inline-block; font-size: 13px; letter-spacing: 2px; text-transform: uppercase; color: var(--brand); margin-bottom: 10px; }
.section-head { max-width: 680px; margin: 0 auto 38px; text-align: center; }
.section-head h2 { font-size: 26px; font-weight: 500; margin-bottom: 8px; }
.section-head p { color: var(--ink-2); margin: 0; }
.lead { font-size: 16px; color: var(--ink-2); }
.cta-band { background: linear-gradient(120deg,#ff8a3d,var(--brand)); color: #fff; padding: 48px 40px; text-align: center; }
.cta-band h2 { color: #fff; font-size: 28px; margin-bottom: 12px; }
.cta-band p { opacity: .95; margin-bottom: 22px; }
.cta-band .btn--ghost { color: #fff; border-color: rgba(255,255,255,.7); }
.cta-band .btn--ghost:hover { background: #fff; color: var(--brand); border-color: #fff; }
.hero__media { display: grid; gap: 14px; }
.hero__media .mock { background: #fff; border: 1px solid var(--line); padding: 16px 18px; }
.hero__media .mock b { display: block; font-size: 15px; margin-bottom: 2px; }
.hero__media .mock p { margin: 0; font-size: 13px; color: var(--muted); }

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .grid--4 { grid-template-columns: repeat(3, 1fr); }
  .footer__cols { grid-template-columns: 1fr 1fr 1fr; }
}
@media (max-width: 860px) {
  .nav__search { display: none; }
  .hero .container { grid-template-columns: 1fr; }
  .catbar { display: none; }
  .banner__inner { max-width: 100%; padding: 32px; }
  .banner__deco { display: none; }
  .grid--4, .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .feature { grid-template-columns: 1fr !important; }
  .cap-grid { grid-template-columns: repeat(2, 1fr); }
  .mini-grid { grid-template-columns: repeat(2, 1fr); }
  .hl-strip { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .topbar__left span.hide-sm, .nav__cart { display: none; }
  .nav__menu {
    position: fixed; inset: calc(var(--header-h)) 0 auto 0; background: #fff; flex-direction: column; align-items: stretch;
    height: auto; padding: 8px 0; gap: 0; box-shadow: var(--shadow); transform: translateY(-140%); transition: .3s; border-bottom: 1px solid var(--line);
  }
  .nav__menu.is-open { transform: none; }
  .nav__menu a { height: auto; padding: 14px 20px; }
  .nav__menu a::after { display: none; }
  .nav__menu .btn { margin: 10px 20px 0; }
  .nav__toggle { display: flex; }
  .grid--4, .grid--3, .grid--2 { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr; }
  .cap-grid, .mini-grid { grid-template-columns: 1fr; }
  .footer__cols { grid-template-columns: 1fr 1fr; }
  .banner { min-height: 300px; }
  .banner h1 { font-size: 28px; }
  .sec-head h2 { font-size: 22px; }
}

/* ---- 二维码 / 防 spam ---- */
.qr-block { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 22px; }
.qr-item { background: var(--tile); border: 1px solid var(--line); padding: 14px; text-align: center; }
.qr-item img { width: 100%; max-width: 200px; height: auto; display: block; margin: 0 auto 10px; object-fit: contain; background: #fff; }
.qr-item span { font-size: 13px; color: var(--ink-2); }
.hp-field { position: absolute !important; left: -9999px; width: 1px; height: 1px; opacity: 0; overflow: hidden; }
@media (max-width: 640px) { .qr-block { grid-template-columns: 1fr 1fr; gap: 10px; } }