/* =========================================================
   DeepEng 新官网 —— 设计系统
   风格：明亮 / 活泼 / 圆润（少儿英语向）
   ========================================================= */

/* ---------- 字体 ---------- */
@import url('https://fonts.googleapis.com/css2?family=Baloo+2:wght@500;600;700;800&family=Nunito:wght@400;600;700;800&family=Noto+Sans+SC:wght@400;500;700;900&display=swap');

/* ---------- 设计变量 ---------- */
:root {
  --blue:   #3B82F6;
  --blue-6: #2563EB;
  --sky:    #38BDF8;
  --orange: #FB923C;
  --yellow: #FBBF24;
  --green:  #34D399;
  --pink:   #F472B6;

  --ink:    #1F2937;
  --muted:  #6B7280;
  --bg:     #FFFDF8;
  --bg-soft:#EFF6FF;
  --bg-tint:#FFF4E6;
  --card:   #FFFFFF;

  --r-xl: 32px;
  --r-lg: 26px;
  --r-md: 18px;
  --r-sm: 12px;
  --r-pill: 999px;

  --sh-soft: 0 12px 30px rgba(59, 130, 246, .12);
  --sh-card: 0 18px 40px rgba(31, 41, 55, .08);
  --sh-hover: 0 22px 48px rgba(59, 130, 246, .22);

  --container: 1180px;
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: 'Nunito', 'Noto Sans SC', system-ui, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
h1, h2, h3, h4, .display { font-family: 'Baloo 2', 'Noto Sans SC', sans-serif; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; display: block; }
.container { width: 100%; max-width: var(--container); margin: 0 auto; padding: 0 20px; }
.w-full { width: 100%; }
.text-center { text-align: center; }

/* ---------- 装饰色块 / 背景 ---------- */
.blob {
  position: absolute; border-radius: 50%;
  filter: blur(8px); opacity: .55; z-index: 0; pointer-events: none;
}
.blob.b1 { width: 320px; height: 320px; background: radial-gradient(circle at 30% 30%, var(--sky), transparent 70%); }
.blob.b2 { width: 260px; height: 260px; background: radial-gradient(circle at 30% 30%, var(--yellow), transparent 70%); }
.blob.b3 { width: 300px; height: 300px; background: radial-gradient(circle at 30% 30%, var(--pink), transparent 70%); }

.section { position: relative; padding: 84px 0; overflow: hidden; }
.section.soft { background: var(--bg-soft); }
.section.tint { background: var(--bg-tint); }
.section-title {
  font-size: clamp(28px, 4vw, 42px); font-weight: 800; text-align: center;
  margin: 0 0 10px;
}
.section-sub { text-align: center; color: var(--muted); margin: 0 auto 48px; max-width: 640px; font-size: 17px; }
.gradient-text {
  background: linear-gradient(120deg, var(--blue), var(--sky) 60%, var(--green));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px; justify-content: center;
  padding: 13px 28px; border-radius: var(--r-pill); border: none;
  font-family: 'Nunito', 'Noto Sans SC', sans-serif; font-weight: 800; font-size: 16px;
  cursor: pointer; transition: transform .2s ease, box-shadow .2s ease, background .2s;
}
.btn-primary { background: linear-gradient(120deg, var(--blue), var(--sky)); color: #fff; box-shadow: var(--sh-soft); }
.btn-primary:hover { transform: translateY(-3px); box-shadow: var(--sh-hover); }
.btn-accent { background: linear-gradient(120deg, var(--orange), var(--yellow)); color: #fff; box-shadow: 0 12px 30px rgba(251,146,60,.3); }
.btn-accent:hover { transform: translateY(-3px); }
.btn-ghost { background: #fff; color: var(--blue-6); box-shadow: var(--sh-card); }
.btn-ghost:hover { transform: translateY(-3px); }
.btn-lg { padding: 16px 38px; font-size: 18px; }

/* ---------- 导航栏 ---------- */
.navbar {
  position: sticky; top: 0; z-index: 100; background: rgba(255,255,255,.82);
  backdrop-filter: blur(12px); border-bottom: 1px solid rgba(59,130,246,.08);
}
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 72px; }
.brand { display: flex; align-items: center; gap: 10px; font-family: 'Baloo 2'; font-weight: 800; font-size: 22px; color: var(--ink); }
.brand .logo-badge {
  width: 42px; height: 42px; border-radius: 14px; display: grid; place-items: center;
  background: linear-gradient(135deg, var(--blue), var(--sky)); color: #fff; font-size: 22px;
  box-shadow: var(--sh-soft); transform: rotate(-6deg);
}
.nav-links { display: flex; align-items: center; gap: 6px; list-style: none; margin: 0; padding: 0; }
.nav-links a {
  padding: 9px 16px; border-radius: var(--r-pill); font-weight: 700; color: var(--muted);
  transition: background .2s, color .2s;
}
.nav-links a:hover { background: var(--bg-soft); color: var(--blue-6); }
.nav-links a.active { background: linear-gradient(120deg, var(--blue), var(--sky)); color: #fff; }
.nav-cta { margin-left: 12px; }
.nav-toggle {
  display: none;
  width: 28px; height: 24px;
  background: none; border: none; cursor: pointer;
  flex-direction: column; justify-content: space-between; padding: 0;
}
.nav-toggle span {
  display: block; width: 100%; height: 3px; border-radius: 3px;
  background: var(--ink); transition: transform .3s ease, opacity .2s ease;
}
.nav-toggle.open span:nth-child(1) { transform: translateY(10.5px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-10.5px) rotate(-45deg); }

/* ---------- Hero ---------- */
.hero { position: relative; padding: 70px 0 90px; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 40px; align-items: center; position: relative; z-index: 1; }
.hero h1 { font-size: clamp(34px, 5vw, 56px); line-height: 1.15; margin: 14px 0 18px; }
.hero p.lead { font-size: 19px; color: var(--muted); margin-bottom: 30px; max-width: 480px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px; background: #fff; color: var(--blue-6);
  padding: 7px 16px; border-radius: var(--r-pill); font-weight: 700; font-size: 14px; box-shadow: var(--sh-card);
}
.hero-badge .dot { width: 9px; height: 9px; border-radius: 50%; background: var(--green); }
.hero-art { position: relative; min-height: 380px; display: grid; place-items: center; }
.phone-mock {
  width: 230px; height: 460px; background: #fff; border-radius: 40px; padding: 14px;
  box-shadow: var(--sh-card); border: 6px solid #fff; position: relative; z-index: 2;
  animation: floaty 5s ease-in-out infinite;
}
.phone-mock .screen { width: 100%; height: 100%; border-radius: 28px; background: linear-gradient(160deg, var(--blue), var(--sky)); display: grid; place-items: center; color: #fff; text-align: center; }
.phone-mock .screen .big { font-family: 'Baloo 2'; font-size: 30px; font-weight: 800; }
.float-chip {
  position: absolute; background: #fff; border-radius: 18px; padding: 12px 16px; font-weight: 800;
  box-shadow: var(--sh-card); z-index: 3; display: flex; align-items: center; gap: 8px;
}
.float-chip.c1 { top: 12%; left: -6%; color: var(--blue-6); animation: floaty 4s ease-in-out infinite; }
.float-chip.c2 { bottom: 16%; right: -4%; color: var(--orange); animation: floaty 6s ease-in-out infinite; }
.float-chip.c3 { bottom: 2%; left: 16%; color: var(--green); animation: floaty 5.5s ease-in-out infinite; }

@keyframes floaty { 0%,100% { transform: translateY(0); } 50% { transform: translateY(-14px); } }

/* ---------- 特性区块（首页） ---------- */
.feature { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; align-items: center; }
.feature.reverse .feature-media { order: -1; }
.feature-text h2 { font-size: clamp(26px, 3.4vw, 38px); font-weight: 800; margin: 0 0 6px; }
.feature-text .sub { color: var(--orange); font-weight: 800; margin-bottom: 22px; }

.tab-card {
  background: #fff; border-radius: var(--r-lg); padding: 18px 22px; margin-bottom: 16px;
  box-shadow: var(--sh-card); cursor: pointer; transition: transform .25s, box-shadow .25s, background .25s;
  border: 2px solid transparent; display: flex; align-items: center; gap: 14px;
}
.tab-card:hover { transform: translateY(-4px); }
.tab-card.active { background: linear-gradient(120deg, var(--blue), var(--sky)); color: #fff; border-color: rgba(255,255,255,.5); }
.tab-card .tc-emoji { font-size: 26px; }
.tab-card .tc-title { font-weight: 800; font-size: 18px; }
.tab-card .tc-desc { font-size: 14px; opacity: .8; }
.tab-card.active .tc-desc { opacity: .95; }

.list-row { display: flex; gap: 14px; margin-bottom: 18px; align-items: flex-start; }
.list-row .lr-dot { flex: none; width: 14px; height: 14px; border-radius: 50%; background: var(--orange); margin-top: 8px; box-shadow: 0 0 0 5px rgba(251,146,60,.18); }
.list-row h4 { margin: 0 0 4px; font-size: 17px; }
.list-row p { margin: 0; color: var(--muted); font-size: 15px; }

.feature-media img { width: 100%; max-width: 420px; margin: 0 auto; border-radius: var(--r-lg); filter: drop-shadow(0 18px 30px rgba(31,41,55,.12)); }
.media-stage { background: #fff; border-radius: var(--r-xl); padding: 26px; box-shadow: var(--sh-card); display: grid; place-items: center; }

/* ---------- 下载区 ---------- */
.download { background: linear-gradient(120deg, #EFF6FF, #FFF4E6); }
.download-cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; margin: 36px 0; }
.dl-card {
  background: #fff; border-radius: var(--r-lg); padding: 24px; display: flex; align-items: center;
  gap: 16px; box-shadow: var(--sh-card); cursor: pointer; transition: transform .25s, box-shadow .25s;
}
.dl-card:hover { transform: translateY(-6px); box-shadow: var(--sh-hover); }
.dl-card .dl-icon { width: 54px; height: 54px; border-radius: 16px; display: grid; place-items: center; font-size: 26px; background: var(--bg-soft); }
.dl-card h4 { margin: 0; font-size: 18px; }
.dl-card p { margin: 2px 0 0; color: var(--muted); font-size: 13px; }
.qr-panel { display: none; gap: 24px; flex-wrap: wrap; justify-content: center; margin-top: 10px; }
.qr-panel.show { display: flex; }
.qr-box { width: 160px; background: #fff; border-radius: var(--r-md); padding: 16px; box-shadow: var(--sh-card); text-align: center; }
.qr-box img { width: 120px; height: 120px; margin: 0 auto 8px; border-radius: 12px; object-fit: cover; }
.qr-box .qr-label { font-weight: 800; font-size: 14px; }
.qr-box a.dl-link { display: inline-block; margin-top: 8px; padding: 6px 16px; border-radius: var(--r-pill); background: linear-gradient(120deg, var(--blue), var(--sky)); color: #fff; font-size: 13px; font-weight: 700; }

/* ---------- 内页页首 ---------- */
.page-hero { padding: 110px 0 60px; background: linear-gradient(120deg, #EFF6FF, #FFF4E6); text-align: center; position: relative; overflow: hidden; }
.page-hero .page-title { font-size: clamp(32px, 5vw, 48px); font-weight: 800; margin: 0 0 12px; color: var(--ink); }
.page-hero .page-sub { font-size: 18px; color: var(--muted); max-width: 640px; margin: 0 auto; }


/* ---------- 联系卡片 ---------- */
.contact-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.contact-card { background: #fff; border-radius: var(--r-xl); padding: 36px 28px; text-align: center; box-shadow: var(--sh-card); transition: transform .3s, box-shadow .3s; }
.contact-card:hover { transform: translateY(-10px); box-shadow: var(--sh-hover); }
.contact-icon { width: 72px; height: 72px; border-radius: 22px; display: grid; place-items: center; margin: 0 auto 18px; font-size: 32px; color: #fff; background: linear-gradient(135deg, var(--blue), var(--sky)); }
.contact-card.green .contact-icon { background: linear-gradient(135deg, var(--green), var(--sky)); }
.contact-card.orange .contact-icon { background: linear-gradient(135deg, var(--orange), var(--yellow)); }
.contact-card.purple .contact-icon { background: linear-gradient(135deg, #8B5CF6, #A78BFA); }
.contact-card h3 { margin: 0 0 6px; font-size: 20px; }
.contact-card p { margin: 0; color: var(--muted); font-weight: 600; }

/* ---------- 表单 ---------- */
.form-card { background: #fff; border-radius: var(--r-xl); padding: 36px; box-shadow: var(--sh-card); max-width: 560px; margin: 0 auto; }
.form-row { margin-bottom: 18px; }
.form-row label { display: block; font-weight: 700; margin-bottom: 8px; color: var(--ink); }
.form-control {
  width: 100%; padding: 14px 18px; border: 2px solid #E5E7EB; border-radius: var(--r-md);
  font-family: inherit; font-size: 16px; transition: border-color .2s, box-shadow .2s; background: #fff;
}
.form-control:focus { outline: none; border-color: var(--blue); box-shadow: 0 0 0 4px rgba(59,130,246,.15); }
textarea.form-control { resize: vertical; min-height: 130px; }
.form-note { font-size: 14px; color: var(--muted); text-align: center; margin-top: 14px; }
.alert { padding: 14px 18px; border-radius: var(--r-md); margin-bottom: 18px; font-weight: 700; }
.alert.ok { background: #ECFDF5; color: #047857; }
.alert.err { background: #FEF2F2; color: #B91C1C; }

/* ---------- 产品页 ---------- */
.product-row { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; align-items: center; margin-bottom: 56px; }
.product-row.reverse .product-media { order: -1; }
.product-media .pm-card { background: linear-gradient(150deg, var(--bg-soft), #fff); border-radius: var(--r-xl); padding: 30px; box-shadow: var(--sh-card); text-align: center; }
.product-media .pm-emoji { font-size: 80px; }
.product-row h3 { font-size: 28px; margin: 0 0 12px; }
.product-row p { color: var(--muted); white-space: pre-line; }

.prod-mini-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 22px; margin-top: 40px; }
.prod-mini { background: #fff; border-radius: var(--r-lg); padding: 28px; box-shadow: var(--sh-card); position: relative; transition: transform .25s; }
.prod-mini:hover { transform: translateY(-6px); }
.prod-mini .pmi-emoji { font-size: 38px; }
.prod-mini h4 { margin: 10px 0 8px; font-size: 20px; }
.prod-mini p { margin: 0; color: var(--muted); font-size: 14px; }

/* ---------- 价格页 ---------- */
.price-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; max-width: 760px; margin: 0 auto; }
.price-card { background: #fff; border-radius: var(--r-xl); padding: 40px 34px; box-shadow: var(--sh-card); position: relative; }
.price-card.featured { background: linear-gradient(160deg, var(--blue), var(--sky)); color: #fff; transform: scale(1.04); box-shadow: var(--sh-hover); }
.price-badge { position: absolute; top: -14px; left: 50%; transform: translateX(-50%); background: var(--orange); color: #fff; padding: 6px 18px; border-radius: var(--r-pill); font-weight: 800; font-size: 13px; box-shadow: 0 8px 18px rgba(251,146,60,.4); }
.price-card h3 { margin: 0; font-size: 24px; }
.price-card .pc-period { opacity: .8; font-size: 14px; }
.price-card .pc-price { font-family: 'Baloo 2'; font-size: 48px; font-weight: 800; margin: 16px 0; }
.price-card ul { list-style: none; padding: 0; margin: 0 0 26px; }
.price-card li { display: flex; gap: 10px; align-items: flex-start; margin-bottom: 12px; font-weight: 600; }
.price-card li .ck { color: var(--green); font-weight: 800; }
.price-card.featured li .ck { color: #fff; }

/* ---------- 协议页 ---------- */
.doc { max-width: 820px; margin: 0 auto; background: #fff; border-radius: var(--r-xl); padding: 44px; box-shadow: var(--sh-card); }
.doc h1 { font-size: 28px; margin: 0 0 6px; }
.doc .meta { color: var(--muted); font-size: 14px; margin-bottom: 24px; }
.doc h2 { font-size: 20px; margin: 26px 0 8px; }
.doc p { color: #374151; }
.doc ol, .doc ul { padding-left: 22px; color: #374151; }
.doc table { width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 14px; }
.doc table th, .doc table td { border: 1px solid #E5E7EB; padding: 10px 12px; text-align: left; vertical-align: top; }
.doc table th { background: var(--bg-soft); font-weight: 800; }
.doc table tr:nth-child(even) td { background: #F8FAFF; }
.doc-nav { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-bottom: 30px; }

/* ---------- 页脚 ---------- */
.footer { background: linear-gradient(160deg, #1E293B, #0F172A); color: #CBD5E1; border-radius: 40px 40px 0 0; margin-top: 40px; padding: 60px 0 30px; }
.footer .f-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 30px; }
.footer h3 { color: #fff; font-size: 16px; margin: 0 0 16px; }
.footer ul { list-style: none; padding: 0; margin: 0; }
.footer ul li { margin-bottom: 10px; }
.footer ul a, .footer ul li { color: #94A3B8; font-size: 14px; }
.footer ul a:hover { color: #fff; }
.footer .f-brand { display: flex; align-items: center; gap: 10px; font-family: 'Baloo 2'; font-weight: 800; font-size: 22px; color: #fff; margin-bottom: 12px; }
.footer .f-brand .logo-badge { width: 40px; height: 40px; }
.brand .logo-img, .footer .f-brand .logo-img { width: 40px; height: 40px; border-radius: 12px; object-fit: contain; box-shadow: var(--sh-soft); }
.footer .f-slogan { color: #94A3B8; }
.footer hr { border: none; border-top: 1px solid rgba(255,255,255,.1); margin: 30px 0 18px; }
.footer .f-bottom { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px; font-size: 13px; color: #94A3B8; }
.footer .f-bottom a { color: #CBD5E1; }

/* ---------- 回到顶部 / 动画 ---------- */
.back-top { position: fixed; right: 22px; bottom: 22px; width: 50px; height: 50px; border-radius: 50%; background: linear-gradient(120deg, var(--blue), var(--sky)); color: #fff; border: none; font-size: 22px; cursor: pointer; box-shadow: var(--sh-hover); opacity: 0; pointer-events: none; transition: opacity .3s, transform .3s; z-index: 90; }
.back-top.show { opacity: 1; pointer-events: auto; }
.back-top:hover { transform: translateY(-4px); }

.reveal { opacity: 0; transform: translateY(28px); transition: opacity .6s ease, transform .6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .nav-links {
    position: absolute; top: 72px; left: 0; right: 0; background: #fff;
    flex-direction: column; padding: 0 16px; box-shadow: var(--sh-card);
    border-radius: 0 0 var(--r-lg) var(--r-lg);
    display: flex;
    max-height: 0; opacity: 0; overflow: hidden;
    transform: translateY(-10px);
    transition: max-height .35s ease, opacity .25s ease, transform .3s ease, padding .35s ease;
  }
  .nav-links.open { max-height: 400px; opacity: 1; transform: none; padding: 16px; }
  .nav-toggle { display: flex; }
  .hero-grid, .feature, .product-row, .price-grid, .contact-grid, .download-cards, .prod-mini-grid, .footer .f-grid { grid-template-columns: 1fr; }
  .feature.reverse .feature-media, .product-row.reverse .product-media { order: 0; }
  .price-card.featured { transform: none; }
  .hero-art { min-height: 300px; }
}
@media (max-width: 560px) {
  .section { padding: 60px 0; }
  .dl-card { flex-direction: column; text-align: center; }
}

/* ---------- 精致 SVG 图标系统 ---------- */
.icon-svg { display: block; }
.tc-icon {
  width: 44px; height: 44px; border-radius: 12px;
  display: grid; place-items: center;
  background: var(--bg-soft); color: var(--blue-6);
  flex: none;
}
.tab-card.active .tc-icon { background: rgba(255,255,255,.22); color: #fff; }

/* ---------- 无图特性布局 ---------- */
.feature { display: block; max-width: 760px; margin: 0 auto; }
.feature-text { width: 100%; }
.feature-text h2, .feature-text .sub { text-align: center; }
.feature-text .sub { margin-bottom: 32px; }

/* ---------- 产品描述列表 ---------- */
.pd-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 14px; }
.pd-list li { display: flex; gap: 12px; align-items: flex-start; }
.pd-list .pd-check {
  flex: none; width: 22px; height: 22px; border-radius: 50%;
  background: var(--bg-soft); color: var(--green);
  display: grid; place-items: center; margin-top: 2px;
}
.pd-list strong { display: block; font-weight: 800; color: var(--ink); margin-bottom: 2px; }
.pd-list span { color: var(--muted); }

/* ---------- 产品页图标与无图布局 ---------- */
.p-icon {
  display: inline-flex; align-items: center; justify-content: center;
  width: 48px; height: 48px; border-radius: 14px; margin-right: 12px;
  vertical-align: middle; background: var(--bg-soft); color: var(--blue-6);
}
.p-icon-blue { background: #EFF6FF; color: var(--blue-6); }
.p-icon-orange { background: #FFF4E6; color: var(--orange); }
.p-icon-green { background: #ECFDF5; color: #059669; }
.p-icon-yellow { background: #FEF9C3; color: #B45309; }

.product-row { display: block; max-width: 780px; margin: 0 auto 56px; }
.product-row h3 { display: flex; align-items: center; margin-bottom: 18px; }
.product-text { width: 100%; }

.prod-mini .pmi-icon {
  width: 52px; height: 52px; border-radius: 14px; margin-bottom: 14px;
}

/* 下载/联系图标颜色 */
.dl-icon { color: var(--blue-6); }
.contact-icon svg { stroke-width: 1.8; }