/* Foottec 官网样式 · 品牌规范：深青 #006B6B / 浅青 #E1F5EE / 暖灰 #F1EFE8 / 深墨 #2C2C2A */
:root {
  --brand: #006B6B;
  --brand-dark: #085041;
  --brand-light: #E1F5EE;
  --warm: #F1EFE8;
  --ink: #2C2C2A;
  --ink-2: #6B6B66;
  --line: #E0E0DC;
  --bg: #FAFAF8;
  --radius: 12px;
  --maxw: 1120px;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--ink); background: var(--bg); line-height: 1.75; font-size: 16px;
}
img { max-width: 100%; display: block; }
a { color: var(--brand); text-decoration: none; }
.container { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ---------- 导航 ---------- */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,.95); backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav-inner { display: flex; align-items: center; gap: 28px; height: 64px; }
.nav-logo { display: flex; align-items: center; gap: 10px; font-weight: 600; font-size: 20px; color: var(--ink); }
.nav-logo img { height: 34px; width: auto; }
.nav-links { display: flex; gap: 24px; margin-left: auto; }
.nav-links a { color: var(--ink); font-size: 15px; }
.nav-links a:hover, .nav-links a.active { color: var(--brand); font-weight: 500; }
.nav-cta {
  background: var(--brand); color: #fff !important; padding: 8px 22px;
  border-radius: 999px; font-weight: 500;
}
.nav-burger { display: none; margin-left: auto; background: none; border: none; font-size: 26px; cursor: pointer; color: var(--ink); line-height: 1; }
@media (max-width: 860px) {
  .nav-links {
    display: none; position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; flex-direction: column; gap: 0; padding: 8px 20px 16px;
    border-bottom: 1px solid var(--line);
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 10px 0; border-bottom: 1px dashed var(--line); }
  .nav-burger { display: block; }
  .nav-inner { gap: 12px; }
  .nav-logo { font-size: 17px; }
  .nav-logo img { height: 28px; }
}

/* ---------- 通用区块 ---------- */
.section { padding: 64px 0; }
.section.tight { padding: 40px 0; }
.section.alt { background: #fff; }
.section.warm { background: var(--warm); }
.section-title { text-align: center; font-size: 30px; font-weight: 600; color: var(--brand-dark); margin-bottom: 8px; }
.section-sub { text-align: center; color: var(--ink-2); font-size: 15px; margin-bottom: 40px; }
@media (max-width: 640px) {
  .section { padding: 44px 0; }
  .section-title { font-size: 24px; }
}
.badge {
  display: inline-block; background: var(--brand-light); color: var(--brand-dark);
  border-radius: 4px; padding: 2px 10px; font-size: 13px; margin-right: 8px;
}
.btn {
  display: inline-block; background: var(--brand); color: #fff; border: none;
  padding: 14px 40px; border-radius: 999px; font-size: 16px; font-weight: 500;
  cursor: pointer; text-align: center; transition: opacity .2s;
}
.btn:hover { opacity: .88; }
.btn.block { display: block; width: 100%; }
.btn.ghost { background: #fff; color: var(--brand); border: 1.5px solid var(--brand); }
.btn.small { padding: 8px 22px; font-size: 14px; }
.btn:disabled { opacity: .5; cursor: not-allowed; }

/* ---------- Hero ---------- */
.hero { background: linear-gradient(135deg, #F4FAF8 0%, #E1F5EE 100%); padding: 72px 0; }
.hero-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: 48px; align-items: center; }
.hero h1 { font-size: 38px; line-height: 1.4; font-weight: 600; color: var(--ink); }
.hero h1 em { color: var(--brand); font-style: normal; }
.hero .slogan2 { font-size: 20px; color: var(--ink-2); margin: 18px 0 6px; }
.hero .steps { color: var(--brand-dark); font-size: 16px; margin-bottom: 30px; }
.hero-video video { width: 100%; border-radius: var(--radius); box-shadow: 0 12px 40px rgba(0,60,50,.14); background: #000; }
@media (max-width: 860px) {
  .hero { padding: 44px 0; }
  .hero-grid { grid-template-columns: 1fr; gap: 28px; }
  .hero h1 { font-size: 27px; }
  .hero .slogan2 { font-size: 17px; }
}

/* ---------- 卡片 ---------- */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; }
.card {
  background: #fff; border-radius: var(--radius); padding: 28px;
  box-shadow: 0 4px 20px rgba(0,0,0,.05); border: 1px solid var(--line);
}
.card h3 { font-size: 19px; color: var(--brand-dark); margin-bottom: 10px; }
.card p { color: var(--ink-2); font-size: 15px; }
.card .num { font-size: 40px; font-weight: 700; color: var(--brand); line-height: 1.2; }
.card .unit { font-size: 15px; color: var(--ink-2); font-weight: 400; }

/* ---------- 人群入口 ---------- */
.crowd-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.crowd-card {
  border-radius: var(--radius); padding: 40px 36px; color: #fff; position: relative; overflow: hidden;
}
.crowd-card.kids { background: linear-gradient(135deg, #2C6E9E 0%, #4C97C9 100%); }
.crowd-card.elder { background: linear-gradient(135deg, #6B5B95 0%, #9B8AC4 100%); }
.crowd-card h3 { font-size: 26px; color: #fff; margin-bottom: 8px; }
.crowd-card p { font-size: 15px; opacity: .92; margin-bottom: 20px; }
.crowd-card .btn { background: #fff; color: var(--ink); padding: 10px 28px; }
@media (max-width: 720px) { .crowd-grid { grid-template-columns: 1fr; } }

/* ---------- 产品卡 ---------- */
.prod-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 24px; }
.prod-card {
  background: #fff; border-radius: var(--radius); overflow: hidden;
  border: 1px solid var(--line); box-shadow: 0 4px 20px rgba(0,0,0,.05);
  display: flex; flex-direction: column; transition: transform .2s, box-shadow .2s;
}
.prod-card:hover { transform: translateY(-4px); box-shadow: 0 10px 32px rgba(0,0,0,.1); }
.prod-card .imgbox { position: relative; background: #F6F6F4; }
.prod-card .imgbox img { width: 100%; aspect-ratio: 16/10; object-fit: cover; }
.prod-card .tagline {
  position: absolute; top: 12px; left: 12px; background: rgba(0,107,107,.92); color: #fff;
  font-size: 12px; padding: 3px 10px; border-radius: 4px;
}
.prod-card .body { padding: 20px 22px 24px; flex: 1; display: flex; flex-direction: column; }
.prod-card h3 { font-size: 18px; color: var(--ink); }
.prod-card .desc { color: var(--ink-2); font-size: 13.5px; margin: 6px 0 14px; flex: 1; }
.prod-card .price { font-size: 26px; font-weight: 700; color: var(--brand); }
.prod-card .price small { font-size: 13px; color: var(--ink-2); font-weight: 400; }
.prod-card .btn { margin-top: 14px; padding: 10px; font-size: 15px; }
.prod-note { text-align: center; color: var(--ink-2); font-size: 13.5px; margin-top: 18px; }

/* ---------- 流程步骤 ---------- */
.steps-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
.step-card { text-align: center; padding: 28px 16px; background: #fff; border-radius: var(--radius); border: 1px solid var(--line); }
.step-card .icon { width: 64px; height: 64px; margin: 0 auto 14px; border-radius: 50%; background: var(--brand-light); display: flex; align-items: center; justify-content: center; font-size: 30px; }
.step-card h3 { font-size: 17px; color: var(--brand-dark); margin-bottom: 6px; }
.step-card p { font-size: 13.5px; color: var(--ink-2); }
.step-card .no { display: inline-block; margin-bottom: 10px; color: var(--brand); font-weight: 700; font-size: 14px; letter-spacing: 2px; }
@media (max-width: 860px) { .steps-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 480px) { .steps-grid { grid-template-columns: 1fr; } }

/* ---------- 信任条 ---------- */
.trust-bar { background: var(--brand); color: #fff; padding: 34px 0; text-align: center; }
.trust-bar .line { font-size: 21px; font-weight: 500; margin-bottom: 6px; }
.trust-bar .sub { font-size: 14px; opacity: .85; }

/* ---------- 论文卡 ---------- */
.paper-group-title { font-size: 20px; color: var(--brand-dark); margin: 36px 0 16px; border-left: 4px solid var(--brand); padding-left: 12px; }
.paper-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 24px; margin-bottom: 14px; }
.paper-card .title { font-size: 15.5px; font-weight: 600; color: var(--ink); }
.paper-card .meta { font-size: 13px; color: var(--ink-2); margin: 4px 0 8px; }
.paper-card .finding { font-size: 14px; color: var(--ink); background: var(--brand-light); border-radius: 8px; padding: 10px 14px; }
.paper-card .finding::before { content: "核心发现"; display: block; font-size: 11px; color: var(--brand-dark); letter-spacing: 1px; margin-bottom: 2px; }
.paper-card .doi { font-size: 12px; color: var(--ink-2); margin-top: 8px; word-break: break-all; }

/* ---------- 拍摄指南 ---------- */
.photo-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.photo-item { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.photo-item img { width: 100%; aspect-ratio: 3/3.4; object-fit: cover; }
.photo-item .cap { padding: 12px 16px; }
.photo-item .cap b { color: var(--brand-dark); font-size: 15px; }
.photo-item .cap span { display: block; font-size: 13px; color: var(--ink-2); }
@media (max-width: 720px) { .photo-grid { grid-template-columns: repeat(2, 1fr); } }

/* ---------- 下单表单 ---------- */
.order-wrap { max-width: 760px; margin: 0 auto; }
.order-steps { display: flex; margin: 30px 0 34px; }
.order-steps .st { flex: 1; text-align: center; position: relative; font-size: 14px; color: var(--ink-2); }
.order-steps .st::before {
  content: attr(data-n); display: block; width: 34px; height: 34px; line-height: 34px;
  margin: 0 auto 6px; border-radius: 50%; background: #EDEDEA; color: var(--ink-2); font-weight: 600;
}
.order-steps .st.on { color: var(--brand); font-weight: 500; }
.order-steps .st.on::before { background: var(--brand); color: #fff; }
.order-steps .st:not(:last-child)::after {
  content: ""; position: absolute; top: 17px; left: calc(50% + 24px); right: calc(-50% + 24px);
  border-top: 2px dashed var(--line);
}
.form-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 32px 30px; }
.form-card h3 { font-size: 19px; color: var(--brand-dark); margin-bottom: 18px; }
.field { margin-bottom: 18px; }
.field label { display: block; font-size: 14px; font-weight: 500; margin-bottom: 6px; }
.field label .req { color: #C0392B; margin-left: 2px; }
.field label .hint { font-weight: 400; color: var(--ink-2); font-size: 12.5px; }
.field input, .field select, .field textarea {
  width: 100%; padding: 11px 14px; border: 1.5px solid var(--line); border-radius: 8px;
  font-size: 15px; font-family: inherit; background: #fff; color: var(--ink);
}
.field input:focus, .field select:focus, .field textarea:focus { outline: none; border-color: var(--brand); }
.field textarea { min-height: 72px; resize: vertical; }
.field .err { color: #C0392B; font-size: 12.5px; margin-top: 4px; display: none; }
.field.invalid input { border-color: #C0392B; }
.field.invalid .err { display: block; }
.row2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.row3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 14px; }
@media (max-width: 560px) { .row2, .row3 { grid-template-columns: 1fr; } }
.code-row { display: flex; gap: 12px; }
.code-row input { flex: 1; }
.code-row .btn { white-space: nowrap; width: 130px; padding: 11px 0; font-size: 14px; }
.group-tip { background: var(--brand-light); border-radius: 8px; padding: 10px 14px; font-size: 13.5px; color: var(--brand-dark); margin-bottom: 18px; }

/* 款式选择 */
.style-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 8px; }
@media (max-width: 560px) { .style-grid { grid-template-columns: 1fr; } }
.style-opt { display: flex; gap: 14px; border: 2px solid var(--line); border-radius: var(--radius); padding: 14px; cursor: pointer; background: #fff; align-items: center; }
.style-opt img { width: 86px; height: 60px; object-fit: cover; border-radius: 6px; flex-shrink: 0; }
.style-opt .info b { display: block; font-size: 15px; color: var(--ink); }
.style-opt .info span { font-size: 12.5px; color: var(--ink-2); display: block; }
.style-opt .info .p { color: var(--brand); font-weight: 700; font-size: 16px; }
.style-opt input { display: none; }
.style-opt.sel { border-color: var(--brand); background: #F4FAF8; }

/* 照片上传 */
.upload-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 560px) { .upload-grid { grid-template-columns: repeat(2, 1fr); } }
.up-item { border: 1.5px dashed var(--line); border-radius: var(--radius); padding: 10px; text-align: center; background: #FCFCFB; }
.up-item .ph { aspect-ratio: 1/1.05; border-radius: 8px; overflow: hidden; background: #F1F1EF; display: flex; align-items: center; justify-content: center; margin-bottom: 8px; position: relative; }
.up-item .ph img.example { width: 100%; height: 100%; object-fit: cover; opacity: .38; }
.up-item .ph .plus { position: absolute; font-size: 30px; color: var(--ink-2); font-weight: 300; }
.up-item .ph img.preview { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; }
.up-item .ph .okmark { position: absolute; top: 6px; right: 6px; background: var(--brand); color: #fff; border-radius: 50%; width: 22px; height: 22px; line-height: 22px; font-size: 13px; }
.up-item .name { font-size: 13px; font-weight: 500; }
.up-item .tip { font-size: 11.5px; color: var(--ink-2); }
.up-item input[type=file] { display: none; }
.up-item.has { border-style: solid; border-color: var(--brand); }

/* 成功页 */
.success-card { text-align: center; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 44px 28px; }
.success-card .big { font-size: 44px; }
.success-card h2 { color: var(--brand-dark); font-size: 24px; margin: 12px 0 6px; }
.success-card .ordno { font-size: 15px; color: var(--ink-2); margin-bottom: 22px; }
.success-card .ordno b { color: var(--ink); letter-spacing: 1px; }
.pay-box { background: var(--warm); border-radius: var(--radius); padding: 24px; display: flex; gap: 24px; align-items: center; text-align: left; }
.pay-box img { width: 190px; border-radius: 10px; flex-shrink: 0; }
.pay-box .amt { font-size: 30px; font-weight: 700; color: var(--brand); margin: 4px 0 10px; }
.pay-box li { font-size: 13.5px; color: var(--ink-2); margin: 4px 0 4px 18px; }
@media (max-width: 600px) { .pay-box { flex-direction: column; text-align: center; } .pay-box li { text-align: left; } }

/* ---------- FAQ ---------- */
.faq-item { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); margin-bottom: 12px; overflow: hidden; }
.faq-item .q { padding: 16px 22px; font-weight: 500; cursor: pointer; display: flex; justify-content: space-between; gap: 12px; }
.faq-item .q::after { content: "+"; color: var(--brand); font-size: 20px; line-height: 1.3; }
.faq-item.open .q::after { content: "−"; }
.faq-item .a { display: none; padding: 0 22px 18px; color: var(--ink-2); font-size: 14.5px; }
.faq-item.open .a { display: block; }

/* ---------- 视频块 ---------- */
.video-block video { width: 100%; border-radius: var(--radius); background: #000; box-shadow: 0 8px 30px rgba(0,0,0,.12); }
/* 竖屏视频（720×1280）：按视口高度约束，确保视频+标题一屏可见 */
.video-block.portrait video {
  width: auto; height: auto;
  max-height: 70vh;            /* 视频高度最多占屏幕的 70% */
  max-width: min(420px, 92vw);
  margin: 0 auto; display: block;
}
.video-block.portrait { text-align: center; }

/* ---------- 页脚 ---------- */
footer { background: #22322F; color: #C9D6D2; padding: 48px 0 32px; font-size: 14px; }
.foot-grid { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 32px; margin-bottom: 32px; }
footer h4 { color: #fff; font-size: 15px; margin-bottom: 12px; }
footer a { color: #C9D6D2; }
footer li { list-style: none; margin: 6px 0; }
.foot-bottom { border-top: 1px solid rgba(255,255,255,.12); padding-top: 20px; text-align: center; font-size: 12.5px; color: #8FA5A0; }
@media (max-width: 720px) { .foot-grid { grid-template-columns: 1fr; } }

/* ---------- 客服机器人 ---------- */
.chat-fab {
  position: fixed; right: 18px; bottom: 18px; z-index: 200;
  width: 56px; height: 56px; border-radius: 50%; background: var(--brand); color: #fff;
  border: none; font-size: 24px; cursor: pointer; box-shadow: 0 6px 20px rgba(0,80,70,.35);
}
.chat-panel {
  position: fixed; right: 14px; bottom: 86px; z-index: 201;
  width: min(360px, calc(100vw - 28px)); height: 480px; max-height: calc(100vh - 110px);
  background: #fff; border-radius: 16px; box-shadow: 0 12px 48px rgba(0,0,0,.18);
  display: none; flex-direction: column; overflow: hidden;
}
.chat-panel.open { display: flex; }
.chat-head { background: var(--brand); color: #fff; padding: 14px 18px; }
.chat-head b { font-size: 15px; }
.chat-head span { display: block; font-size: 12px; opacity: .85; }
.chat-body { flex: 1; overflow-y: auto; padding: 16px; background: #F7F9F8; }
.msg { max-width: 82%; margin-bottom: 12px; padding: 10px 14px; border-radius: 12px; font-size: 14px; line-height: 1.6; white-space: pre-wrap; }
.msg.bot { background: #fff; border: 1px solid var(--line); border-top-left-radius: 4px; }
.msg.user { background: var(--brand); color: #fff; margin-left: auto; border-top-right-radius: 4px; }
.chat-quick { display: flex; flex-wrap: wrap; gap: 8px; padding: 10px 14px; background: #fff; border-top: 1px solid var(--line); }
.chat-quick button { border: 1px solid var(--brand); color: var(--brand); background: #fff; border-radius: 999px; font-size: 12.5px; padding: 4px 12px; cursor: pointer; }
.chat-input { display: flex; gap: 8px; padding: 10px 12px; background: #fff; }
.chat-input input { flex: 1; border: 1.5px solid var(--line); border-radius: 999px; padding: 8px 14px; font-size: 14px; }
.chat-input button { background: var(--brand); border: none; color: #fff; border-radius: 999px; padding: 0 18px; cursor: pointer; font-size: 14px; }

/* ---------- 其他 ---------- */
.page-head { background: linear-gradient(135deg, #E9F6F2, #F6F6F3); padding: 52px 0 40px; text-align: center; }
.page-head h1 { font-size: 32px; color: var(--brand-dark); }
.page-head p { color: var(--ink-2); margin-top: 8px; }
@media (max-width: 640px) { .page-head h1 { font-size: 25px; } .page-head { padding: 36px 0 28px; } }
.text-muted { color: var(--ink-2); }
.divider { height: 1px; background: var(--line); margin: 22px 0; }
.notice { background: #FDF3E7; border-left: 4px solid #BA7517; border-radius: 8px; padding: 12px 16px; font-size: 13.5px; color: #7A5210; margin: 16px 0; }