/* ============ 乐奇积木 · 设计系统 ============ */
:root {
  --red: #e23b3b;
  --yellow: #f5a623;
  --blue: #2563eb;
  --green: #22c55e;
  --ink: #111827;
  --ink-soft: #4b5563;
  --muted: #9ca3af;
  --line: #e5e7eb;
  --bg: #f7f8fb;
  --card: #ffffff;
  --shadow: 0 6px 24px rgba(17, 24, 39, 0.08);
  --shadow-lg: 0 16px 48px rgba(17, 24, 39, 0.14);
  --radius: 16px;
  --radius-sm: 10px;
  --maxw: 1200px;
  --brand: linear-gradient(135deg, #e23b3b 0%, #f5a623 50%, #2563eb 100%);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }
input, select, textarea { font-family: inherit; font-size: 15px; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ============ 顶栏 ============ */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--line);
}
.nav { display: flex; align-items: center; gap: 32px; height: 72px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 900; font-size: 22px; letter-spacing: -0.5px; }
.logo .mark {
  width: 36px; height: 36px; border-radius: 8px;
  background: var(--brand);
  position: relative;
  box-shadow: 0 4px 10px rgba(226,59,59,.3);
}
.logo .mark::before, .logo .mark::after {
  content: ""; position: absolute; width: 8px; height: 8px; border-radius: 50%;
  background: rgba(255,255,255,.85); top: 6px;
}
.logo .mark::before { left: 7px; }
.logo .mark::after { left: 21px; }
.logo span { background: var(--brand); -webkit-background-clip: text; background-clip: text; color: transparent; }
.nav-links { display: flex; gap: 26px; margin-left: 8px; }
.nav-links a { font-weight: 600; color: var(--ink-soft); padding: 8px 4px; border-bottom: 2px solid transparent; transition: .2s; }
.nav-links a:hover, .nav-links a.active { color: var(--ink); border-color: var(--red); }
.nav-right { margin-left: auto; display: flex; align-items: center; gap: 14px; }
.cart-btn {
  position: relative; display: inline-flex; align-items: center; gap: 6px;
  padding: 9px 16px; border-radius: 999px; background: var(--ink); color: #fff; font-weight: 700;
}
.cart-btn .count {
  background: var(--yellow); color: var(--ink); font-size: 12px; font-weight: 900;
  min-width: 20px; height: 20px; border-radius: 999px; display: inline-flex; align-items: center; justify-content: center; padding: 0 5px;
}
.burger { display: none; font-size: 26px; }

/* ============ 按钮 ============ */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 12px 22px; border-radius: 999px; font-weight: 700; transition: .18s; }
.btn-primary { background: var(--brand); color: #fff; box-shadow: 0 6px 16px rgba(226,59,59,.3); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(226,59,59,.4); }
.btn-dark { background: var(--ink); color: #fff; }
.btn-dark:hover { transform: translateY(-2px); }
.btn-ghost { border: 2px solid var(--line); color: var(--ink); background: #fff; }
.btn-ghost:hover { border-color: var(--ink); }
.btn-sm { padding: 8px 14px; font-size: 14px; }
.btn-block { width: 100%; }

/* ============ 英雄区 ============ */
.hero { padding: 56px 0 40px; position: relative; overflow: hidden; }
.hero-grid { display: grid; grid-template-columns: 1.1fr 1fr; gap: 40px; align-items: center; }
.hero h1 { font-size: clamp(34px, 5vw, 56px); line-height: 1.08; letter-spacing: -1px; font-weight: 900; }
.hero h1 .grad { background: var(--brand); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero p.lead { margin-top: 18px; font-size: 18px; color: var(--ink-soft); max-width: 520px; }
.hero-cta { margin-top: 28px; display: flex; gap: 14px; flex-wrap: wrap; }
.hero-stats { margin-top: 36px; display: flex; gap: 32px; }
.hero-stats .stat b { font-size: 28px; display: block; }
.hero-stats .stat span { color: var(--muted); font-size: 14px; }
.hero-art { position: relative; height: 380px; }
.brick-tower { position: absolute; display: grid; gap: 6px; }
.brick {
  border-radius: 8px; position: relative; box-shadow: inset 0 -4px 0 rgba(0,0,0,.12), 0 4px 10px rgba(0,0,0,.12);
}
.brick::before, .brick::after {
  content: ""; position: absolute; top: -6px; width: 14px; height: 8px; border-radius: 4px 4px 0 0; background: inherit;
}
.brick::before { left: 12px; }
.brick::after { right: 12px; }
.b1 { width: 220px; height: 56px; background: var(--red); left: 40px; bottom: 0; }
.b2 { width: 160px; height: 56px; background: var(--yellow); left: 70px; bottom: 62px; }
.b3 { width: 200px; height: 56px; background: var(--blue); left: 30px; bottom: 124px; }
.b4 { width: 120px; height: 56px; background: var(--green); left: 90px; bottom: 186px; }
.floating { animation: float 5s ease-in-out infinite; }
@keyframes float { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-12px)} }

/* ============ 区块 ============ */
.section { padding: 56px 0; }
.section-head { display: flex; align-items: end; justify-content: space-between; margin-bottom: 28px; gap: 16px; flex-wrap: wrap; }
.section-head h2 { font-size: 30px; font-weight: 900; letter-spacing: -0.5px; }
.section-head p { color: var(--ink-soft); }
.eyebrow { color: var(--red); font-weight: 800; font-size: 13px; letter-spacing: 2px; text-transform: uppercase; }

/* ============ 卡片网格 ============ */
.grid { display: grid; gap: 24px; }
.grid-products { grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
.grid-parts { grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); }

.card {
  background: var(--card); border-radius: var(--radius); overflow: hidden;
  box-shadow: var(--shadow); transition: .22s; border: 1px solid var(--line);
  display: flex; flex-direction: column;
}
.card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); }
.card-media {
  position: relative; aspect-ratio: 4/3; display: flex; align-items: center; justify-content: center;
  overflow: hidden;
}
.card-media .stud-bg { position: absolute; inset: 0; opacity: .25; background-image: radial-gradient(circle, #fff 22%, transparent 23%); background-size: 22px 22px; }
.card-tag { position: absolute; top: 12px; left: 12px; background: var(--ink); color: #fff; font-size: 12px; font-weight: 800; padding: 5px 10px; border-radius: 999px; z-index: 2; }
.card-tag.hot { background: var(--red); }
.card-tag.new { background: var(--blue); }
.card-tag.limited { background: #7c3aed; }
.card-body { padding: 18px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.card-series { font-size: 12px; color: var(--muted); font-weight: 700; letter-spacing: 1px; text-transform: uppercase; }
.card-title { font-size: 17px; font-weight: 800; line-height: 1.3; }
.card-meta { display: flex; gap: 14px; font-size: 13px; color: var(--ink-soft); flex-wrap: wrap; }
.card-meta .dot { color: var(--line); }
.card-foot { margin-top: auto; display: flex; align-items: center; justify-content: space-between; padding-top: 8px; }
.price { font-size: 22px; font-weight: 900; color: var(--red); }
.price .cur { font-size: 14px; }
.rating { color: var(--yellow); font-size: 13px; font-weight: 700; }

/* CSS 积木插画（产品图占位，主题统一） */
.brick-art { width: 70%; height: 70%; border-radius: 14px; display: grid; grid-template-columns: repeat(3,1fr); grid-template-rows: repeat(3,1fr); gap: 5px; padding: 6px; background: rgba(0,0,0,.05); }
.brick-art i { border-radius: 6px; box-shadow: inset 0 -3px 0 rgba(0,0,0,.18); position: relative; }
.brick-art i::before { content:""; position:absolute; top:3px; left:50%; transform:translateX(-50%); width:30%; height:30%; border-radius:50%; background:rgba(255,255,255,.35); }

/* ============ 筛选条 ============ */
.toolbar { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; margin-bottom: 24px; }
.chips { display: flex; gap: 8px; flex-wrap: wrap; }
.chip { padding: 8px 16px; border-radius: 999px; border: 1px solid var(--line); background: #fff; font-weight: 600; color: var(--ink-soft); transition: .15s; }
.chip.active { background: var(--ink); color: #fff; border-color: var(--ink); }
.search { flex: 1; min-width: 220px; position: relative; }
.search input { width: 100%; padding: 11px 16px 11px 40px; border: 1px solid var(--line); border-radius: 999px; outline: none; background: #fff; }
.search::before { content: "🔍"; position: absolute; left: 14px; top: 50%; transform: translateY(-50%); font-size: 14px; }
.search input:focus { border-color: var(--blue); }

/* ============ 详情页 ============ */
.detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: start; padding: 40px 0; }
.detail-media { border-radius: var(--radius); overflow: hidden; background: #fff; box-shadow: var(--shadow); aspect-ratio: 1; display: flex; align-items: center; justify-content: center; border: 1px solid var(--line); position: sticky; top: 96px; }
.detail h1 { font-size: 34px; font-weight: 900; letter-spacing: -0.5px; }
.detail .lead { color: var(--ink-soft); margin-top: 10px; font-size: 17px; }
.detail .price-big { font-size: 38px; color: var(--red); font-weight: 900; margin: 20px 0; }
.spec-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 12px; margin: 24px 0; }
.spec { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 14px; }
.spec .k { font-size: 12px; color: var(--muted); font-weight: 700; text-transform: uppercase; letter-spacing: 1px; }
.spec .v { font-size: 18px; font-weight: 800; margin-top: 2px; }
.qty-row { display: flex; align-items: center; gap: 14px; margin: 20px 0; }
.qty { display: inline-flex; align-items: center; border: 2px solid var(--line); border-radius: 999px; overflow: hidden; }
.qty button { width: 40px; height: 40px; font-size: 20px; font-weight: 800; background: #fff; }
.qty input { width: 48px; text-align: center; border: none; font-weight: 800; font-size: 16px; }
.detail-desc { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 20px; margin-top: 8px; color: var(--ink-soft); }

/* ============ 购物车 / 表单 ============ */
.cart-layout { display: grid; grid-template-columns: 1fr 340px; gap: 32px; align-items: start; padding: 40px 0; }
.cart-items { display: flex; flex-direction: column; gap: 14px; }
.cart-row { display: grid; grid-template-columns: 80px 1fr auto auto auto; gap: 16px; align-items: center; background: #fff; border: 1px solid var(--line); border-radius: var(--radius-sm); padding: 14px; }
.cart-row .thumb { width: 80px; height: 64px; border-radius: 8px; overflow: hidden; display: flex; align-items: center; justify-content: center; }
.cart-row .del { color: var(--muted); font-size: 20px; padding: 6px; }
.cart-row .del:hover { color: var(--red); }
.summary { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow); position: sticky; top: 96px; }
.summary h3 { font-size: 20px; margin-bottom: 16px; }
.summary .row { display: flex; justify-content: space-between; padding: 8px 0; color: var(--ink-soft); }
.summary .total { font-size: 26px; font-weight: 900; color: var(--ink); border-top: 2px solid var(--line); margin-top: 8px; padding-top: 14px; }
.field { margin-bottom: 16px; }
.field label { display: block; font-weight: 700; margin-bottom: 6px; font-size: 14px; }
.field input, .field select, .field textarea { width: 100%; padding: 12px 14px; border: 1px solid var(--line); border-radius: var(--radius-sm); outline: none; background: #fff; }
.field input:focus, .field select:focus, .field textarea:focus { border-color: var(--blue); }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.empty { text-align: center; padding: 80px 24px; color: var(--muted); }
.empty .big { font-size: 56px; }

/* ============ 批量生成页 ============ */
.bulk-layout { display: grid; grid-template-columns: 420px 1fr; gap: 32px; align-items: start; padding: 40px 0; }
.panel { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 26px; box-shadow: var(--shadow); }
.panel h3 { font-size: 20px; margin-bottom: 6px; }
.panel .hint { color: var(--muted); font-size: 14px; margin-bottom: 18px; }
.tab-bar { display: flex; gap: 8px; margin-bottom: 18px; }
.tab { flex: 1; padding: 10px; border-radius: var(--radius-sm); border: 2px solid var(--line); font-weight: 700; color: var(--ink-soft); }
.tab.active { background: var(--ink); color: #fff; border-color: var(--ink); }
.result-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.badge-ok { background: #dcfce7; color: #166534; font-weight: 800; padding: 6px 12px; border-radius: 999px; font-size: 13px; }

/* ============ 页脚 ============ */
.site-footer { background: var(--ink); color: #cbd5e1; margin-top: 40px; padding: 48px 0 28px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 32px; }
.footer-grid h4 { color: #fff; font-size: 15px; margin-bottom: 14px; }
.footer-grid a { display: block; padding: 4px 0; color: #94a3b8; }
.footer-grid a:hover { color: #fff; }
.footer-bottom { margin-top: 32px; padding-top: 20px; border-top: 1px solid #374151; color: #64748b; font-size: 13px; text-align: center; }

/* ============ 提示条 ============ */
.toast { position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%) translateY(20px); background: var(--ink); color: #fff; padding: 14px 22px; border-radius: 999px; font-weight: 700; box-shadow: var(--shadow-lg); opacity: 0; transition: .25s; z-index: 200; pointer-events: none; }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ============ 响应式 ============ */
@media (max-width: 900px) {
  .hero-grid, .detail-grid, .cart-layout, .bulk-layout { grid-template-columns: 1fr; }
  .hero-art { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .detail-media { position: static; }
}
@media (max-width: 640px) {
  .nav-links { display: none; }
  .burger { display: block; }
  .wrap { padding: 0 16px; }
  .cart-row { grid-template-columns: 64px 1fr auto; }
  .cart-row .qty, .cart-row .del { grid-column: 2 / -1; justify-self: end; }
  .footer-grid { grid-template-columns: 1fr; }
  .spec-grid { grid-template-columns: 1fr; }
}