/* =========================================================
   贝叶斯 AI 编程科创营 · 官网样式
   风格:简洁现代教育风 · 品牌蓝为主 + 暖橙点缀
   仅用系统字体,无外部依赖(国内 / 断网可正常打开)
   ========================================================= */

:root {
  /* 品牌色 */
  --brand: #2e5bff;
  --brand-ink: #1f43c9;
  --brand-deep: #142a86;
  --brand-050: #eef3ff;
  --brand-100: #dbe6ff;
  --brand-200: #b9ccff;

  --accent: #ff8a3d;      /* 暖橙,仅用于关键动作/高亮 */
  --accent-ink: #e2681a;
  --accent-050: #fff3ea;

  /* 中性色 */
  --ink: #131a2e;         /* 主文字(深海军蓝,比纯黑柔) */
  --ink-2: #414c66;       /* 次级文字 */
  --muted: #6b7794;       /* 辅助/说明文字 */
  --line: #e7ebf3;
  --bg: #ffffff;
  --bg-soft: #f5f8ff;
  --bg-tint: #eef3ff;

  /* 排版 */
  --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB",
    "Source Han Sans SC", "Noto Sans SC", system-ui, -apple-system, sans-serif;
  --font-lat: "Segoe UI", system-ui, -apple-system, "SF Pro Display", Roboto,
    "Helvetica Neue", sans-serif;

  /* 尺寸 */
  --maxw: 1120px;
  --radius: 18px;
  --radius-lg: 26px;
  --shadow-sm: 0 2px 10px rgba(24, 44, 120, 0.06);
  --shadow: 0 12px 34px rgba(24, 44, 120, 0.10);
  --shadow-lg: 0 26px 60px rgba(24, 44, 120, 0.16);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }

.wrap { width: 100%; max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- 通用排版 ---------- */
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--brand-ink);
  background: var(--brand-050);
  border: 1px solid var(--brand-100);
  padding: 7px 14px;
  border-radius: 999px;
}
.eyebrow .dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }

.section { padding: 84px 0; }
.section-head { max-width: 720px; margin-bottom: 46px; }
.section-head.center { margin-left: auto; margin-right: auto; text-align: center; }
.section h2 {
  font-size: clamp(26px, 3.4vw, 38px);
  line-height: 1.25;
  margin: 16px 0 14px;
  letter-spacing: -0.01em;
  font-weight: 800;
}
.section h2 .hl { color: var(--brand); }
.section .lead { font-size: 17px; color: var(--ink-2); margin: 0; }

.mono-num {
  font-family: var(--font-lat);
  font-variant-numeric: tabular-nums;
  font-weight: 800;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  font-size: 16px;
  font-weight: 700;
  padding: 14px 26px;
  border-radius: 999px;
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
  white-space: nowrap;
}
.btn svg { width: 19px; height: 19px; }
.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 10px 24px rgba(255, 122, 45, 0.34);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 16px 30px rgba(255, 122, 45, 0.42); }
.btn-ghost {
  background: #fff;
  color: var(--brand-ink);
  border-color: var(--brand-100);
  box-shadow: var(--shadow-sm);
}
.btn-ghost:hover { transform: translateY(-2px); border-color: var(--brand-200); }
.btn-lg { font-size: 17px; padding: 16px 32px; }
.btn.disabled { opacity: 0.55; cursor: not-allowed; pointer-events: none; }

/* ---------- 顶部导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid rgba(231, 235, 243, 0.9);
}
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 11px; font-weight: 800; font-size: 18px; letter-spacing: -0.01em; }
.brand .logo { width: 34px; height: 34px; flex: none; }
.brand-logo-img { border-radius: 10px; object-fit: cover; box-shadow: 0 2px 8px rgba(24,44,120,0.14); }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a { font-weight: 600; color: var(--ink-2); font-size: 15px; transition: color 0.15s; }
.nav-links a:hover { color: var(--brand); }
.nav-cta { display: flex; align-items: center; gap: 12px; }
.nav-toggle { display: none; }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; }
.hero::before {
  content: "";
  position: absolute; inset: 0;
  background:
    radial-gradient(760px 440px at 82% -6%, rgba(46, 91, 255, 0.16), transparent 62%),
    radial-gradient(620px 420px at 6% 8%, rgba(255, 138, 61, 0.10), transparent 60%),
    linear-gradient(180deg, var(--bg-soft), #fff 78%);
  z-index: -2;
}
.hero::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    linear-gradient(rgba(46, 91, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(46, 91, 255, 0.05) 1px, transparent 1px);
  background-size: 46px 46px;
  mask-image: radial-gradient(680px 420px at 78% 20%, #000 0%, transparent 72%);
  z-index: -1;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 40px;
  align-items: center;
  padding: 74px 0 88px;
}
.hero h1 {
  font-size: clamp(34px, 5vw, 56px);
  line-height: 1.12;
  letter-spacing: -0.02em;
  margin: 20px 0 20px;
  font-weight: 900;
}
.hero h1 .hl { color: var(--brand); }
.hero .sub { font-size: clamp(17px, 2vw, 20px); color: var(--ink-2); max-width: 540px; margin: 0 0 32px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.hero-trust { margin-top: 30px; display: flex; gap: 22px; flex-wrap: wrap; color: var(--muted); font-size: 14px; font-weight: 600; }
.hero-trust span { display: inline-flex; align-items: center; gap: 7px; }
.hero-trust svg { width: 16px; height: 16px; color: var(--brand); }

/* Hero:理念驱动、居中 */
.hero-center { text-align: center; }
.hero-inner { max-width: 860px; margin: 0 auto; padding: 104px 0 96px; }
.hero-center .eyebrow { margin-bottom: 26px; }
.hero-center h1 {
  font-size: clamp(38px, 6vw, 66px);
  line-height: 1.08;
  letter-spacing: -0.025em;
  margin: 0 0 26px;
  font-weight: 900;
}
.hero-center h1 .hl { color: var(--brand); }
.manifesto {
  font-size: clamp(22px, 3.2vw, 34px);
  line-height: 1.4;
  font-weight: 800;
  color: var(--ink);
  margin: 0 0 20px;
  letter-spacing: -0.01em;
}
.manifesto b { color: var(--brand); font-weight: 800; position: relative; white-space: nowrap; }
.manifesto b::after {
  content: ""; position: absolute; left: -2px; right: -2px; bottom: 4px; height: 10px;
  background: var(--accent); opacity: 0.22; border-radius: 4px; z-index: -1;
}
.hero-center .sub { font-size: clamp(16px, 2vw, 19px); color: var(--ink-2); max-width: 620px; margin: 0 auto 30px; }
.hero-tags { display: inline-flex; align-items: center; gap: 16px; color: var(--muted); font-size: 15px; font-weight: 700; flex-wrap: wrap; justify-content: center; }
.hero-tags span { color: var(--brand-ink); }
.hero-tags i { width: 5px; height: 5px; border-radius: 50%; background: var(--brand-200); display: inline-block; }
.hero-scroll { display: grid; place-items: center; color: var(--brand-200); padding-bottom: 22px; animation: bob 1.8s ease-in-out infinite; }
@keyframes bob { 0%,100% { transform: translateY(0); } 50% { transform: translateY(7px); } }

/* 为什么学 AI 编程 */
.why-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.why-card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 32px 28px; box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.why-card:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
.why-card .ic { width: 54px; height: 54px; border-radius: 16px; display: grid; place-items: center; margin-bottom: 20px; background: var(--brand-050); }
.why-card .ic svg { width: 28px; height: 28px; color: var(--brand); }
.why-card:nth-child(2) .ic { background: var(--accent-050); } .why-card:nth-child(2) .ic svg { color: var(--accent-ink); }
.why-card h3 { margin: 0 0 12px; font-size: 20px; font-weight: 800; line-height: 1.35; }
.why-card p { margin: 0; color: var(--ink-2); font-size: 15px; }
/* 图标块升级为渐变(不再素) */
.why-card .ic { background: linear-gradient(140deg, var(--brand), var(--brand-deep)); box-shadow: 0 9px 20px rgba(46,91,255,0.26); }
.why-card .ic svg { color: #fff; }
.why-card:nth-child(2) .ic { background: linear-gradient(140deg, #ffa15c, var(--accent-ink)); box-shadow: 0 9px 20px rgba(255,138,61,0.28); }
.why-card:nth-child(2) .ic svg { color: #fff; }

/* ---------- Hero:深色全屏背景大图 ---------- */
.hero-dark {
  position: relative; overflow: hidden;
  min-height: calc(100vh - 68px);
  display: flex; align-items: center;
  background: #0a1026;
}
.hero-bg {
  position: absolute; inset: 0;
  background: url("hero-bg.jpg") center right / cover no-repeat;
  animation: heroFloat 18s ease-in-out infinite alternate;
}
@keyframes heroFloat { from { transform: scale(1.04) translateX(0); } to { transform: scale(1.10) translateX(-1.5%); } }
.hero-scrim {
  position: absolute; inset: 0;
  background:
    linear-gradient(90deg, #070c1e 0%, rgba(8,14,32,0.94) 24%, rgba(8,14,32,0.58) 50%, rgba(8,14,32,0.12) 78%, rgba(8,14,32,0) 100%),
    linear-gradient(180deg, rgba(8,14,32,0.5) 0%, transparent 26%, transparent 70%, rgba(8,14,32,0.55) 100%);
}
.hero-dark-inner { position: relative; z-index: 2; width: 100%; }
.hero-text { max-width: 640px; }
.eyebrow-dark { color: #cdd7ff; background: rgba(255,255,255,0.09); border-color: rgba(255,255,255,0.20); }
.hero-dark h1 {
  font-size: clamp(42px, 6.2vw, 74px); line-height: 1.04; letter-spacing: -0.025em;
  margin: 24px 0 22px; font-weight: 900; color: #fff;
}
.hero-dark h1 .hl { color: #7ea6ff; }
.hero-dark .manifesto { color: #fff; font-size: clamp(20px, 2.6vw, 30px); line-height: 1.45; font-weight: 800; margin: 0 0 20px; letter-spacing: -0.01em; }
.hero-dark .manifesto b { color: #fff; position: relative; white-space: nowrap; background: linear-gradient(transparent 62%, rgba(255,138,61,0.55) 62%); padding: 0 2px; }
.hero-dark .manifesto b::after { display: none; }
.hero-dark .sub { color: rgba(255,255,255,0.80); font-size: clamp(16px, 2vw, 19px); max-width: 540px; margin: 0 0 32px; line-height: 1.7; }
.hero-credit { display: inline-flex; align-items: center; gap: 11px; color: rgba(255,255,255,0.74); font-size: 15px; font-weight: 600; flex-wrap: wrap; }
.hero-credit b { color: #fff; font-weight: 800; }
.hero-credit .dotb { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); flex: none; box-shadow: 0 0 12px 2px rgba(255,138,61,0.7); }

/* ---------- Hero:深色科技感 · 大字排版 + 背景氛围 ---------- */
.hero-dark {
  position: relative; overflow: hidden;
  min-height: calc(100vh - 68px);
  display: flex; align-items: center;
  background:
    radial-gradient(1100px 620px at 82% -8%, rgba(58, 104, 255, 0.42), transparent 58%),
    radial-gradient(760px 520px at 8% 112%, rgba(255, 138, 61, 0.16), transparent 60%),
    linear-gradient(155deg, #0a1230 0%, #0c1740 46%, #0a1636 100%);
}
/* 极淡网格质感 */
.hero-dark::before {
  content: ""; position: absolute; inset: 0; z-index: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.035) 1px, transparent 1px);
  background-size: 58px 58px;
  -webkit-mask-image: radial-gradient(120% 100% at 80% 0%, #000 30%, transparent 78%);
  mask-image: radial-gradient(120% 100% at 80% 0%, #000 30%, transparent 78%);
}
/* 顶部一道高光,让深色不闷 */
.hero-dark::after {
  content: ""; position: absolute; left: 0; right: 0; top: 0; height: 1px; z-index: 2;
  background: linear-gradient(90deg, transparent, rgba(140,175,255,0.5), transparent);
}
/* 粒子网络画布(app.js 绘制),偏右显现,向左淡出让文字干净 */
.hero-net {
  position: absolute; inset: 0; z-index: 0; width: 100%; height: 100%;
  -webkit-mask-image: linear-gradient(90deg, transparent 6%, #000 46%);
  mask-image: linear-gradient(90deg, transparent 6%, #000 46%);
}
/* 贝叶斯「概率曲线」,呼应品牌名(明显但不压过文字) */
.hero-curve {
  position: absolute; right: 0; top: 52%; transform: translateY(-50%);
  width: min(56%, 700px); z-index: 1; opacity: 0.92; pointer-events: none;
  filter: drop-shadow(0 0 30px rgba(90, 140, 255, 0.6));
}
.hero-curve svg { width: 100%; height: auto; display: block; }
.hero-dark-inner { position: relative; z-index: 3; padding: 40px 0; width: 100%; }
.hero-dark .hero-copy { max-width: 640px; }
.hero-dark .hero-copy h1 {
  font-size: clamp(42px, 6vw, 74px); line-height: 1.04; letter-spacing: -0.03em;
  margin: 24px 0 22px; font-weight: 900; color: #fff;
  text-shadow: 0 2px 30px rgba(10, 20, 60, 0.5);
}
.hero-dark .hero-copy h1 .hl {
  background: linear-gradient(100deg, #7aa0ff, #4d7bff 60%, #6f97ff);
  -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; color: #6f97ff;
}
.hero-dark .tagline {
  font-size: clamp(17px, 2vw, 21px); color: #97a6d4; line-height: 1.6;
  margin: 0 0 38px; max-width: 640px; font-weight: 500;
}
.hero-dark .tagline strong {
  display: inline-block; margin-bottom: 6px; font-weight: 800; letter-spacing: -0.01em;
  color: #fff; font-size: clamp(21px, 2.5vw, 27px); line-height: 1.35;
}
.hero-actions { display: flex; gap: 22px; flex-wrap: wrap; align-items: center; }
.hero-builds { display: flex; flex-direction: column; gap: 3px; padding-left: 22px; border-left: 1px solid rgba(255,255,255,0.14); }
.hero-builds .hb-lbl { font-size: 12.5px; font-weight: 600; color: #8394c2; letter-spacing: 0.04em; }
.hero-builds .hb-tags { font-size: 15px; font-weight: 700; color: #d6e0ff; letter-spacing: 0.01em; }
.hero-builds .hb-tags i { display: inline-block; width: 4px; height: 4px; border-radius: 50%; background: var(--accent); margin: 0 9px; vertical-align: middle; }
.btn-ondark {
  background: rgba(255, 255, 255, 0.07); color: #eaf0ff;
  border-color: rgba(255, 255, 255, 0.22); backdrop-filter: blur(6px);
}
.btn-ondark:hover { transform: translateY(-2px); background: rgba(255, 255, 255, 0.13); border-color: rgba(255, 255, 255, 0.4); }
@keyframes heroFloat { from { transform: translateY(-50%) translateX(0); } to { transform: translateY(-50%) translateX(-14px); } }
@media (prefers-reduced-motion: no-preference) {
  .hero-curve { animation: heroFloat 7s ease-in-out infinite alternate; }
}

/* ---------- 学习产出:大示意图 ---------- */
.out-img { width: 88px; height: 88px; flex: none; border-radius: 16px; object-fit: cover; }

/* ---------- 特性行:为孩子而研发(工具 + 团队) ---------- */
.feature {
  display: grid; grid-template-columns: 1fr 1fr; gap: 44px; align-items: center;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 30px; box-shadow: var(--shadow); margin-bottom: 24px;
}
.feature.reverse .feature-media { order: 2; }
.feature-media { border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); border: 1px solid var(--line); }
.feature-media img { width: 100%; height: 100%; max-height: 400px; object-fit: cover; display: block; }
/* 竖版人物照:完整显示整张照片,不裁切 */
.feature-media--portrait { align-self: center; max-width: 340px; margin: 0 auto; background: #eef2f8; }
.feature-media--portrait img { height: auto; max-height: none; object-fit: contain; }
.feature-kicker { font-size: 13px; font-weight: 700; color: var(--muted); letter-spacing: 0.04em; }
.feature-title { font-size: clamp(28px, 3.2vw, 38px); font-weight: 800; margin: 6px 0 16px; letter-spacing: -0.01em; }
.feature-text > p { color: var(--ink-2); font-size: 16px; line-height: 1.75; margin: 0 0 16px; }
.feature-facts { list-style: none; margin: 0; padding: 0; display: flex; gap: 8px; flex-wrap: wrap; }
.feature-facts li { font-size: 13px; font-weight: 600; color: var(--brand-ink); background: var(--brand-050); border-radius: 8px; padding: 6px 11px; }
.advisor { font-size: 14.5px; color: var(--muted); border-left: 3px solid var(--brand-100); padding-left: 14px; margin-bottom: 0 !important; }
.advisor b { color: var(--ink-2); }

/* 产出卡图标升级为渐变 */
.out .ic { background: linear-gradient(140deg, var(--brand), var(--brand-deep)); box-shadow: 0 8px 18px rgba(46,91,255,0.24); }
.out .ic svg { color: #fff; }
.out:nth-child(3n+2) .ic { background: linear-gradient(140deg, #ffa15c, var(--accent-ink)); box-shadow: 0 8px 18px rgba(255,138,61,0.26); }

/* ---------- 主理人 ---------- */
.founder {
  display: grid; grid-template-columns: 300px 1fr; gap: 42px; align-items: center;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 34px; box-shadow: var(--shadow); margin-bottom: 22px;
}
.founder-photo { border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); }
.founder-photo img { width: 100%; height: 100%; object-fit: cover; display: block; aspect-ratio: 5/6; }
.founder-info h3 { margin: 0 0 5px; font-size: 27px; font-weight: 800; }
.founder-info .role { margin: 0 0 20px; color: var(--brand-ink); font-weight: 700; font-size: 15px; }
.founder-facts { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 13px; }
.founder-facts li { position: relative; padding-left: 30px; color: var(--ink-2); font-size: 15.5px; line-height: 1.55; }
.founder-facts li::before {
  content: ""; position: absolute; left: 0; top: 3px; width: 19px; height: 19px; border-radius: 6px;
  background: var(--brand-050);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%232e5bff' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E");
  background-size: 13px; background-position: center; background-repeat: no-repeat;
}
.founder-facts li b { color: var(--ink); }
.team-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }

/* Hero 图形卡(自绘,无需图片) */
.hero-art { position: relative; }
.hero-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: 22px;
  position: relative;
}
.hero-card .bar { display: flex; gap: 7px; margin-bottom: 16px; }
.hero-card .bar i { width: 11px; height: 11px; border-radius: 50%; display: block; }
.hero-card .bar i:nth-child(1) { background: #ff6058; }
.hero-card .bar i:nth-child(2) { background: #ffbd2e; }
.hero-card .bar i:nth-child(3) { background: #28c840; }
.chat { display: flex; flex-direction: column; gap: 12px; }
.chat .msg { font-size: 14.5px; padding: 12px 15px; border-radius: 14px; max-width: 88%; }
.chat .msg.me { align-self: flex-end; background: var(--brand); color: #fff; border-bottom-right-radius: 5px; }
.chat .msg.ai { align-self: flex-start; background: var(--bg-tint); color: var(--ink); border-bottom-left-radius: 5px; }
.chat .msg.ai .tag { display: inline-flex; align-items: center; gap: 6px; font-weight: 700; color: var(--brand-ink); font-size: 12.5px; margin-bottom: 4px; }
.chat .code { background: #0f1836; color: #c9d6ff; font-family: var(--font-lat); font-size: 12.5px; border-radius: 12px; padding: 13px 15px; line-height: 1.65; overflow: hidden; }
.chat .code .k { color: #7aa2ff; } .chat .code .s { color: #ffb27a; } .chat .code .c { color: #5f6f9c; }
.hero-badge {
  position: absolute; right: -14px; bottom: -18px;
  background: #fff; border: 1px solid var(--line); box-shadow: var(--shadow);
  border-radius: 16px; padding: 12px 16px; display: flex; align-items: center; gap: 11px;
}
.hero-badge .ic { width: 38px; height: 38px; border-radius: 11px; background: var(--accent-050); display: grid; place-items: center; }
.hero-badge .ic svg { width: 21px; height: 21px; color: var(--accent-ink); }
.hero-badge b { display: block; font-size: 14px; }
.hero-badge small { color: var(--muted); font-size: 12.5px; }

/* ---------- 思维框架(招牌视觉) ---------- */
.steps { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; position: relative; }
/* 背后贯穿的连接线 */
.steps::before {
  content: ""; position: absolute; left: 8%; right: 8%; top: 54px; height: 2px;
  background: linear-gradient(90deg, var(--brand-100), var(--brand-200), var(--brand-100));
  z-index: 0;
}
.step {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px 20px 22px;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: transform 0.22s ease, box-shadow 0.22s ease, border-color 0.22s ease;
  z-index: 1;
}
.step:hover { transform: translateY(-7px); box-shadow: var(--shadow); border-color: var(--brand-100); }
.step .bignum {
  position: absolute; top: 2px; right: 14px;
  font-family: var(--font-lat); font-weight: 800; font-size: 62px; line-height: 1;
  color: var(--brand-050); z-index: 0; letter-spacing: -0.02em;
}
.step .ic-tile {
  position: relative; z-index: 1;
  width: 52px; height: 52px; border-radius: 15px; display: grid; place-items: center; margin-bottom: 18px;
  background: linear-gradient(140deg, var(--brand), var(--brand-deep));
  box-shadow: 0 9px 20px rgba(46, 91, 255, 0.30);
}
.step .ic-tile svg { width: 26px; height: 26px; color: #fff; }
.step h3 { position: relative; z-index: 1; margin: 0 0 8px; font-size: 18px; font-weight: 800; }
.step p { position: relative; z-index: 1; margin: 0; color: var(--muted); font-size: 14px; line-height: 1.6; }

/* ---------- 产出网格 ---------- */
.outputs { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.out {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 24px; box-shadow: var(--shadow-sm);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: flex; gap: 16px; align-items: flex-start;
}
.out:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
.out .ic { width: 50px; height: 50px; border-radius: 14px; flex: none; display: grid; place-items: center; background: var(--brand-050); }
.out .ic svg { width: 26px; height: 26px; color: var(--brand); }
.out.a2 .ic { background: var(--accent-050); } .out.a2 .ic svg { color: var(--accent-ink); }
.out h3 { margin: 2px 0 6px; font-size: 18px; font-weight: 800; }
.out p { margin: 0; color: var(--muted); font-size: 14px; }

/* ---------- 品牌故事:贝叶斯肖像 ---------- */
.story-grid { display: grid; grid-template-columns: auto 1fr; gap: 44px; align-items: center; }
.portrait-frame {
  width: 210px; height: 250px; padding: 12px;
  background: linear-gradient(160deg, #fbf7ee, #f3ead6);
  border: 1px solid #e6d7b6;
  border-radius: 16px;
  box-shadow: var(--shadow), inset 0 0 0 6px #fff;
}
.portrait-frame img { width: 100%; height: 100%; object-fit: cover; border-radius: 8px; }
.portrait-ph {
  width: 100%; height: 100%; border-radius: 8px;
  background: repeating-linear-gradient(45deg, #efe6d0, #efe6d0 10px, #ece1c7 10px, #ece1c7 20px);
  display: grid; place-content: center; justify-items: center; gap: 10px;
  color: #9c8a5f; text-align: center; font-size: 13px; font-weight: 700; line-height: 1.5;
}
.portrait-cap { margin-top: 16px; font-family: var(--font-lat); font-weight: 800; font-size: 15px; color: var(--ink); }
.portrait-cap small { font-family: var(--font-sans); font-weight: 600; color: var(--muted); font-size: 12.5px; }

/* ---------- 信任区 ---------- */
.trust-wrap { background: var(--bg-soft); }
.trust { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.tcard {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 34px 32px; box-shadow: var(--shadow-sm);
}
.tcard .badge { display: inline-flex; align-items: center; gap: 9px; font-weight: 800; font-size: 13px; color: var(--brand-ink); background: var(--brand-050); border-radius: 999px; padding: 7px 14px; margin-bottom: 18px; }
.tcard.accent .badge { color: var(--accent-ink); background: var(--accent-050); }
.tcard h3 { margin: 0 0 12px; font-size: 22px; font-weight: 800; line-height: 1.35; }
.tcard p { margin: 0; color: var(--ink-2); font-size: 15.5px; }
.tcard .facts { list-style: none; margin: 18px 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 8px; }
.tcard .facts li { font-size: 13px; font-weight: 600; color: var(--brand-ink); background: var(--brand-050); border-radius: 8px; padding: 6px 11px; }

/* ---------- 联系咨询(素雅收口) ---------- */
.contact { background: var(--bg-soft); }
.contact-inner {
  display: flex; align-items: center; gap: 48px;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 40px 48px; box-shadow: var(--shadow-sm);
}
.contact-inner .txt { flex: 1; }
.contact-inner .txt .eyebrow { margin-bottom: 16px; }
.contact-inner .txt h2 { font-size: clamp(22px, 2.6vw, 30px); margin: 0 0 12px; font-weight: 800; }
.contact-inner .txt p { margin: 0; color: var(--ink-2); font-size: 16px; max-width: 520px; }
.contact-inner .qr { flex: none; width: 186px; box-shadow: none; border: 1px solid var(--line); background: var(--bg-soft); }
.contact-inner .qr .img, .contact-inner .qr .ph { width: 154px; height: 154px; }

/* 二维码块 */
.qr {
  background: #fff; border-radius: 20px; padding: 16px; text-align: center; width: 210px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.22);
}
.qr .img { width: 178px; height: 178px; border-radius: 12px; object-fit: cover; margin: 0 auto; background: var(--bg-tint); }
.qr .ph {
  width: 178px; height: 178px; border-radius: 12px; margin: 0 auto;
  border: 2px dashed var(--brand-200); background: var(--brand-050);
  display: grid; place-items: center; text-align: center; color: var(--brand-ink);
  font-size: 12.5px; font-weight: 700; padding: 12px; line-height: 1.5;
}
.qr .ph svg { width: 30px; height: 30px; margin-bottom: 8px; opacity: 0.7; }
.qr .cap { margin-top: 12px; font-size: 13.5px; font-weight: 700; color: var(--ink); }
.qr .wx { margin-top: 4px; font-size: 12.5px; color: var(--muted); }
.qr .wx b { color: var(--brand-ink); font-family: var(--font-lat); }

/* ---------- 弹层(咨询) ---------- */
.modal { position: fixed; inset: 0; z-index: 80; display: none; place-items: center; padding: 20px; }
.modal.open { display: grid; }
.modal .mask { position: absolute; inset: 0; background: rgba(15, 24, 54, 0.5); backdrop-filter: blur(3px); }
.modal .panel {
  position: relative; background: #fff; border-radius: 24px; padding: 30px; text-align: center;
  box-shadow: var(--shadow-lg); width: 300px; max-width: 100%; animation: pop 0.24s ease;
}
@keyframes pop { from { transform: scale(0.94); opacity: 0; } to { transform: scale(1); opacity: 1; } }
.modal .panel h3 { margin: 0 0 6px; font-size: 20px; font-weight: 800; }
.modal .panel .desc { margin: 0 0 18px; color: var(--muted); font-size: 14px; }
.modal .close { position: absolute; top: 14px; right: 14px; width: 30px; height: 30px; border: none; background: var(--bg-tint); border-radius: 9px; cursor: pointer; color: var(--ink-2); display: grid; place-items: center; }
.modal .close:hover { background: var(--brand-050); }

/* ---------- 下载页 ---------- */
.dl-hero { padding: 56px 0 24px; }
.dl-hero .eyebrow { margin-bottom: 16px; }
.dl-hero h1 { font-size: clamp(30px, 4.4vw, 46px); font-weight: 900; letter-spacing: -0.02em; margin: 0 0 14px; }
.dl-hero p { font-size: 18px; color: var(--ink-2); max-width: 620px; margin: 0; }
.dl-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; }
.dcard {
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius-lg);
  padding: 34px 32px; box-shadow: var(--shadow-sm); display: flex; flex-direction: column;
}
.dcard .top { display: flex; align-items: center; gap: 16px; margin-bottom: 8px; }
.dcard .app-ic { width: 58px; height: 58px; border-radius: 16px; flex: none; display: grid; place-items: center; }
.dcard.c1 .app-ic { background: linear-gradient(135deg, #eaf1ff, #d7e5ff); }
.dcard.c2 .app-ic { background: linear-gradient(135deg, var(--brand), var(--brand-deep)); }
.dcard .app-ic svg { width: 30px; height: 30px; }
.dcard.c1 .app-ic svg { color: var(--brand); } .dcard.c2 .app-ic svg { color: #fff; }
.dcard .kicker { font-size: 12.5px; font-weight: 700; color: var(--muted); letter-spacing: 0.04em; }
.dcard h2 { margin: 2px 0 0; font-size: 24px; font-weight: 800; }
.dcard .ver { font-family: var(--font-lat); font-size: 13px; font-weight: 700; color: var(--brand-ink); background: var(--brand-050); padding: 3px 9px; border-radius: 7px; margin-left: 8px; }
.dcard > p.lead { color: var(--ink-2); font-size: 15.5px; margin: 14px 0 20px; }
.dcard .steps-list { list-style: none; margin: 0 0 24px; padding: 0; display: flex; flex-direction: column; gap: 12px; }
.dcard .steps-list li { display: flex; gap: 13px; align-items: flex-start; font-size: 15px; color: var(--ink-2); }
.dcard .steps-list .n { flex: none; width: 25px; height: 25px; border-radius: 50%; background: var(--brand-050); color: var(--brand-ink); font-family: var(--font-lat); font-weight: 800; font-size: 13px; display: grid; place-items: center; margin-top: 1px; }
.dcard .foot { margin-top: auto; }
.dl-btns { display: flex; gap: 12px; }
.dl-btns .btn { flex: 1; padding-left: 14px; padding-right: 14px; }
.dl-btns .btn svg { width: 18px; height: 18px; }
/* 不是访客当前电脑系统的那个按钮:同款实心橙、但明显变浅 + 不可点(app.js 加 .dl-off) */
.dl-btns .btn.dl-off { opacity: 0.4; cursor: not-allowed; box-shadow: none; }
.dl-btns .btn.dl-off:hover { transform: none; box-shadow: none; }
/* 说明文字:预留 2 行高度(≥ 较长那条的实测 42.9px),让两卡的下载按钮排在同一水平线上 */
.dcard .note { margin: 14px 0 0; font-size: 13px; line-height: 1.65; color: var(--muted); min-height: 46px; }
/* 选错系统弹层的按钮区:上下排、等宽 */
.os-actions { display: flex; flex-direction: column; gap: 10px; }
.os-actions .btn { width: 100%; }
.modal .panel .desc { line-height: 1.7; }
.dl-help { text-align: center; padding: 20px 0 90px; }

/* ---------- 页脚 ---------- */
.footer { background: #0f1836; color: #aeb9d8; padding: 46px 0 40px; }
.footer .cols { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 26px; align-items: flex-start; }
.footer .brand { color: #fff; font-size: 18px; }
.footer .brand .brand-logo-svg { filter: brightness(1.6); }
.footer .tag { margin: 12px 0 0; font-size: 13.5px; color: #8592b8; max-width: 360px; line-height: 1.7; }
.nb { white-space: nowrap; }   /* 让整句短语整体换行,不把末尾几个字甩到下一行落单 */
.footer nav { display: flex; gap: 26px; flex-wrap: wrap; }
.footer nav a { color: #aeb9d8; font-size: 14px; font-weight: 600; transition: color 0.15s; }
.footer nav a:hover { color: #fff; }
.footer .copy { margin-top: 30px; padding-top: 22px; border-top: 1px solid rgba(255,255,255,0.09); font-size: 12.5px; color: #6f7ca6; }

/* ---------- 进场动画 ---------- */
.reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.in { opacity: 1; transform: none; }
.reveal.d1 { transition-delay: 0.06s; } .reveal.d2 { transition-delay: 0.12s; }
.reveal.d3 { transition-delay: 0.18s; } .reveal.d4 { transition-delay: 0.24s; } .reveal.d5 { transition-delay: 0.30s; }
@media (prefers-reduced-motion: reduce) { .reveal { opacity: 1; transform: none; transition: none; } html { scroll-behavior: auto; } }

/* ---------- 响应式 ---------- */
@media (max-width: 940px) {
  .nav-links { display: none; }
  .hero-dark { min-height: auto; }
  .hero-dark-inner { padding: 72px 0 84px; }
  .hero-curve { width: 62%; opacity: 0.32; }
  .feature, .feature.reverse { grid-template-columns: 1fr; gap: 22px; }
  .feature-media--portrait { max-width: 280px; }
  .feature.reverse .feature-media { order: 0; }
  .feature-media img { max-height: 300px; }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .steps::before { display: none; }
  .why-grid { grid-template-columns: 1fr; }
  .outputs { grid-template-columns: repeat(2, 1fr); }
  .trust, .dl-grid, .team-cards { grid-template-columns: 1fr; }
  .founder { grid-template-columns: 1fr; gap: 24px; padding: 26px; }
  .founder-photo { max-width: 300px; margin: 0 auto; }
  .story-grid { grid-template-columns: 1fr; gap: 26px; text-align: center; }
  .story-grid .portrait { margin-inline: auto; }
  .contact-inner { flex-direction: column; text-align: center; gap: 28px; padding: 36px 28px; }
  .contact-inner .txt p { margin-inline: auto; }
  .contact-inner .txt .eyebrow { margin-inline: auto; }
}
@media (max-width: 620px) {
  .wrap { padding: 0 18px; }
  .section { padding: 60px 0; }
  .nav-inner { height: 60px; }
  .brand span { font-size: 16px; }
  .nav-cta { gap: 8px; }
  .nav-cta .btn { padding: 9px 15px; font-size: 14px; }
  .hero-curve { display: none; }
  .hero-actions { width: 100%; gap: 16px; }
  .hero-actions .btn { width: 100%; justify-content: center; }
  .hero-builds { padding-left: 0; border-left: none; }
  .steps { grid-template-columns: 1fr; }
  .outputs { grid-template-columns: 1fr; }
  .brk { display: none; }
  .out-img { width: 68px; height: 68px; }
  .footer .cols { flex-direction: column; }
  .dl-btns { flex-direction: column; }   /* 手机屏窄,两个下载按钮改上下排,免挤压 */
}