/* =========================================================
   北矿伴学官网样式
   设计语言：简洁克制 / 大留白 / 细线卡片 / 学术蓝 + 暖沙点缀
   ========================================================= */

:root {
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --mono: "SF Mono", ui-monospace, "Cascadia Code", Consolas, Menlo, monospace;

  --bg: #ffffff;
  --bg-soft: #f6f7f9;
  --ink: #101828;
  --ink-2: #26303f;
  --muted: #5f6b7c;
  --line: #e7e9ee;
  --brand: #2563eb;
  --brand-deep: #1d4ed8;
  --brand-soft: #eef3fe;
  --dark: #0c1220;
  --dark-line: rgba(255, 255, 255, 0.1);
  --warm: #f6a609;

  --r-sm: 10px;
  --r-md: 14px;
  --r-lg: 20px;

  --container: 1120px;
  --shadow-sm: 0 1px 2px rgba(16, 24, 40, 0.04), 0 1px 3px rgba(16, 24, 40, 0.06);
  --shadow-md: 0 12px 30px -8px rgba(16, 24, 40, 0.16);
}

/* ---------- Reset ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}
img, svg { display: block; }
a { color: inherit; text-decoration: none; }
h1, h2, h3, p, ul, ol { margin: 0; padding: 0; }
ul, ol { list-style: none; }
em { font-style: normal; color: var(--brand); }
code {
  font-family: var(--mono);
  font-size: 0.86em;
  background: var(--bg-soft);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 0.12em 0.45em;
  color: var(--ink-2);
}

.container { max-width: var(--container); margin: 0 auto; padding: 0 28px; }
.sm-only { display: none; }

/* ---------- 通用 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 15px;
  line-height: 1;
  border-radius: 999px;
  padding: 12px 22px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}
.btn svg { width: 17px; height: 17px; flex: none; }
.btn-primary {
  background: var(--brand);
  color: #fff;
  box-shadow: 0 6px 18px -6px rgba(37, 99, 235, 0.5);
}
.btn-primary:hover { background: var(--brand-deep); transform: translateY(-1px); }
.btn-ghost {
  background: transparent;
  color: var(--ink-2);
  border-color: var(--line);
}
.btn-ghost:hover { border-color: #cfd5df; background: var(--bg-soft); }
.btn-lg { padding: 16px 28px; font-size: 17px; }
.btn-lg svg { width: 20px; height: 20px; }
.btn[aria-disabled="true"], .btn.is-off { opacity: 0.55; pointer-events: none; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--brand);
  margin-bottom: 18px;
}
.eyebrow-dot { width: 7px; height: 7px; border-radius: 50%; background: var(--warm); }
.eyebrow-light { color: rgba(255, 255, 255, 0.72); }

.section { padding: 104px 0; }
.section-soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

.sec-head { max-width: 640px; margin-bottom: 56px; }
.sec-head h2 {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.25;
}
.sec-sub { margin-top: 14px; color: var(--muted); font-size: 16.5px; }

/* 滚动出现 */
.reveal { opacity: 0; transform: translateY(16px); transition: opacity 0.6s ease, transform 0.6s ease; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- 导航 ---------- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
}
.site-nav.scrolled { border-bottom-color: var(--line); }
.nav-inner { display: flex; align-items: center; gap: 28px; height: 68px; }
.brand { display: inline-flex; align-items: center; gap: 11px; margin-right: auto; }
.brand-mark {
  width: 34px; height: 34px; border-radius: 10px; overflow: hidden;
  background: #fff; border: 1px solid var(--line); box-shadow: var(--shadow-sm); flex: none;
}
.brand-mark svg { width: 100%; height: 100%; }
.brand-mark.sm { width: 30px; height: 30px; border-radius: 9px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.2; font-weight: 700; font-size: 17px; letter-spacing: 0.01em; }
.brand-text small { font-size: 11px; font-weight: 500; color: var(--muted); letter-spacing: 0.06em; }
.nav-links { display: flex; gap: 4px; }
.nav-links a {
  padding: 8px 14px; border-radius: 8px; color: var(--ink-2);
  font-size: 15px; font-weight: 500; transition: color 0.2s, background 0.2s;
}
.nav-links a:hover { color: var(--brand); background: var(--brand-soft); }
.nav-dl { padding: 10px 20px; }
.nav-dl.is-off { pointer-events: none; opacity: 0.6; }

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; padding: 92px 0 120px; }
.hero-grid {
  display: grid;
  grid-template-columns: 1.08fr 0.92fr;
  gap: 64px;
  align-items: center;
}
.hero h1 {
  font-size: clamp(40px, 5.4vw, 60px);
  line-height: 1.16;
  font-weight: 700;
  letter-spacing: -0.028em;
}
.lead {
  margin: 24px 0 34px;
  color: var(--muted);
  font-size: 17.5px;
  max-width: 34em;
}
.hero-ctas { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }
.hero-note { margin-top: 18px; font-size: 13.5px; color: #98a1b0; }
.hero-note::before { content: "●"; color: #34d399; font-size: 10px; vertical-align: 2px; margin-right: 7px; }

/* 底部微光渐变 */
.hero::after {
  content: "";
  position: absolute; left: 0; right: 0; bottom: 0; height: 240px;
  background: linear-gradient(to top, rgba(238, 243, 254, 0.9), rgba(255, 255, 255, 0));
  pointer-events: none;
}

/* 对话演示卡 */
.hero-demo { position: relative; }
.phone-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--r-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}
.pc-head {
  display: flex; align-items: center; gap: 8px;
  padding: 13px 18px; border-bottom: 1px solid var(--line);
  font-size: 13px; color: var(--muted);
}
.pc-head .pc-tag { margin-left: auto; font-size: 11.5px; color: var(--brand); background: var(--brand-soft); padding: 2px 9px; border-radius: 999px; font-weight: 600; }
.pc-dot { width: 9px; height: 9px; border-radius: 50%; background: #34d399; }
.pc-body { padding: 18px; display: flex; flex-direction: column; gap: 11px; font-size: 14px; }
.bubble {
  max-width: 86%;
  padding: 11px 15px;
  border-radius: 15px;
  line-height: 1.65;
  font-size: 13.5px;
}
.bubble-user { align-self: flex-end; background: var(--brand); color: #fff; border-bottom-right-radius: 4px; }
.bubble-ai {
  align-self: flex-start; background: var(--bg-soft);
  border: 1px solid var(--line); border-bottom-left-radius: 4px;
  color: var(--ink-2);
}
.bubble-kicker { display: inline-block; font-size: 11px; color: var(--brand); font-weight: 600; margin-bottom: 3px; letter-spacing: 0.05em; }
.m { font-family: var(--mono); font-size: 0.92em; }
.bubble-user .m { color: #dbe7ff; }
.tier { display: flex; flex-wrap: wrap; gap: 5px; margin: 2px 0; }
.tier-step {
  font-size: 11px; color: #b6bec9; border: 1px solid var(--line); border-radius: 999px;
  padding: 2px 9px; font-weight: 600; background: #fff;
}
.tier-step.active { color: var(--brand); border-color: rgba(37, 99, 235, 0.35); background: var(--brand-soft); }
.pc-note {
  font-size: 11.5px; color: var(--muted); background: #fff8ec;
  border: 1px dashed #f0d9a8; border-radius: 10px; padding: 8px 12px;
}
.pc-cite {
  font-size: 12px; color: var(--muted); border-top: 1px dashed var(--line);
  padding-top: 11px; margin-top: 4px;
}
.pc-cite::before { content: "📖 "; font-size: 12px; }
.hero-demo::before {
  content: "";
  position: absolute; inset: -40px -30px; z-index: -1;
  background: radial-gradient(220px 160px at 20% 10%, rgba(246, 166, 9, 0.10), transparent 65%),
              radial-gradient(260px 200px at 85% 90%, rgba(37, 99, 235, 0.12), transparent 65%);
  filter: blur(6px);
}

/* ---------- 主张条 ---------- */
.statement { padding: 92px 0 84px; text-align: center; }
.statement-text {
  font-size: clamp(26px, 4vw, 40px);
  font-weight: 700; letter-spacing: -0.02em; line-height: 1.4;
}
.statement-text .hl { color: var(--brand); position: relative; }
.statement-sub { margin-top: 16px; color: var(--muted); font-size: 16.5px; }

/* ---------- 功能特性 ---------- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}
.card {
  background: #fff; border: 1px solid var(--line); border-radius: var(--r-md);
  padding: 30px 30px 34px;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); border-color: #d5dbe5; }
.card-icon {
  display: inline-flex; width: 46px; height: 46px; border-radius: 12px;
  align-items: center; justify-content: center; margin-bottom: 18px;
  background: var(--tint, var(--brand)); color: #fff;
  box-shadow: 0 8px 16px -8px var(--tint, var(--brand));
}
.card-icon svg { width: 24px; height: 24px; }
.feature h3 { font-size: 19px; font-weight: 700; letter-spacing: -0.01em; margin-bottom: 8px; }
.feature p { color: var(--muted); font-size: 15.5px; line-height: 1.75; }

/* ---------- 引导机制 ---------- */
.method-list {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px;
  margin-bottom: 26px;
}
.method-list li {
  background: #fff; border: 1px solid var(--line); border-radius: var(--r-md);
  padding: 26px 22px;
}
.method-num {
  font-family: var(--mono); font-size: 13px; font-weight: 700; color: var(--warm);
  letter-spacing: 0.1em;
}
.method-list strong { display: block; margin: 10px 0 6px; font-size: 16.5px; }
.method-list p { font-size: 14px; color: var(--muted); line-height: 1.7; }
.method-note {
  background: var(--brand-soft); border: 1px solid rgba(37, 99, 235, 0.18);
  border-radius: var(--r-md); padding: 18px 24px; font-size: 15px; color: var(--ink-2);
}
.method-note strong { color: var(--brand); }

/* ---------- 时间线 ---------- */
.timeline { position: relative; display: flex; flex-direction: column; gap: 14px; }
.timeline::before {
  content: ""; position: absolute; left: 9px; top: 16px; bottom: 16px;
  width: 2px; background: var(--line);
}
.tl {
  position: relative; padding: 4px 0 4px 44px;
}
.tl-marker {
  position: absolute; left: 2px; top: 16px; width: 16px; height: 16px;
  border-radius: 50%; background: #fff; border: 3px solid var(--line); box-sizing: border-box;
}
.tl-marker.done { border-color: #10b981; }
.tl-marker.current { border-color: var(--brand); box-shadow: 0 0 0 5px rgba(37, 99, 235, 0.15); }
.tl-marker.todo { border-color: #cbd2dc; }
.tl-head { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.tl-phase { font-family: var(--mono); font-size: 13px; font-weight: 700; color: var(--muted); letter-spacing: 0.05em; }
.badge { font-size: 11.5px; font-weight: 600; padding: 3px 10px; border-radius: 999px; }
.badge-done { color: #047857; background: #e7f7f0; }
.badge-current { color: var(--brand-deep); background: var(--brand-soft); }
.badge-todo { color: #667085; background: #f0f1f4; }
.tl h3 { font-size: 17px; margin: 7px 0 4px; letter-spacing: -0.01em; }
.tl p { color: var(--muted); font-size: 15px; max-width: 640px; }
.tl.is-current .tl-phase { color: var(--brand); }

/* ---------- 下载区 ---------- */
.section.download { padding-top: 20px; }
.download-panel {
  position: relative;
  background:
    radial-gradient(560px 320px at 8% 0%, rgba(37, 99, 235, 0.28), transparent 60%),
    radial-gradient(420px 260px at 100% 100%, rgba(246, 166, 9, 0.16), transparent 55%),
    var(--dark);
  border-radius: 26px;
  color: #fff;
  padding: 64px 56px;
  overflow: hidden;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
}
.dl-copy h2 { font-size: clamp(26px, 3.4vw, 36px); line-height: 1.3; letter-spacing: -0.02em; margin-bottom: 16px; }
.dl-copy p { color: rgba(255, 255, 255, 0.72); font-size: 15.5px; max-width: 30em; }
.dl-meta { margin-top: 22px; font-size: 13px; color: rgba(255, 255, 255, 0.55); font-family: var(--mono); }
.dl-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
/* 下载卡样式仅在下载面板内生效；Hero 主按钮虽复用 .dl-btn 类名做状态管理，但不应套用卡片外观 */
.download-panel .dl-btn {
  display: flex; flex-direction: column; gap: 2px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--dark-line);
  border-radius: var(--r-md);
  padding: 16px 18px;
  transition: background 0.2s ease, transform 0.2s ease, border-color 0.2s ease;
  min-height: 118px;
}
.download-panel .dl-btn:hover { background: rgba(255, 255, 255, 0.12); transform: translateY(-3px); border-color: rgba(255, 255, 255, 0.28); }
.download-panel .dl-btn.is-off { opacity: 0.5; cursor: not-allowed; }
.download-panel .dl-icon { width: 26px; height: 26px; color: #fff; margin-bottom: 8px; }
.download-panel .dl-name { font-weight: 700; font-size: 16px; line-height: 1.3; }
.download-panel .dl-name::after { content: " 下载"; color: rgba(255, 255, 255, 0.65); font-weight: 500; }
.download-panel .dl-sub { font-size: 12px; color: rgba(255, 255, 255, 0.5); line-height: 1.5; }
.download-panel .dl-btn.is-off .dl-name::after { content: ""; }
.dl-note { grid-column: 1 / -1; margin-top: 4px; font-size: 12px; color: rgba(255, 255, 255, 0.45); text-align: center; }

/* ---------- 关于 ---------- */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; }
.about-card h3 { font-size: 17px; margin-bottom: 10px; }
.about-card p { color: var(--muted); font-size: 15.5px; line-height: 1.8; margin-bottom: 20px; }
.about-card p:last-child { margin-bottom: 0; }
.about-list { margin-top: 4px; }
.about-list li { position: relative; padding-left: 20px; color: var(--muted); font-size: 15px; margin-bottom: 9px; }
.about-list li::before {
  content: ""; position: absolute; left: 3px; top: 10px;
  width: 6px; height: 6px; border-radius: 50%; background: var(--warm);
}
.tech-line { margin-top: 26px; font-size: 14.5px; color: var(--muted); text-align: center; }

/* ---------- 页脚 ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--bg-soft); padding: 40px 0; }
.footer-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; flex-wrap: wrap; }
.footer-brand { display: flex; align-items: center; gap: 12px; }
.footer-brand strong { display: block; font-size: 15.5px; }
.footer-brand p { font-size: 13px; color: var(--muted); }
.copyright { color: var(--muted); font-size: 13px; text-align: right; line-height: 1.8; }
.footer-icp { margin-top: 24px; padding-top: 14px; border-top: 1px solid var(--line); text-align: center; }
.footer-icp .icp { margin: 0; color: var(--muted); font-size: 12px; line-height: 1.7; }
.footer-icp .icp a { color: var(--muted); text-decoration: none; }
.footer-icp .icp a:hover { color: var(--brand); }

/* ---------- Toast ---------- */
.toast {
  position: fixed; left: 50%; bottom: 34px; transform: translate(-50%, 20px);
  background: var(--ink); color: #fff; font-size: 14px;
  padding: 12px 20px; border-radius: 12px; box-shadow: var(--shadow-md);
  opacity: 0; pointer-events: none; transition: opacity 0.25s ease, transform 0.25s ease;
  z-index: 99; max-width: min(90vw, 480px); text-align: center;
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

/* ---------- 响应式 ---------- */
@media (max-width: 940px) {
  .hero { padding: 64px 0 90px; }
  .hero-grid { grid-template-columns: 1fr; gap: 56px; }
  .hero-demo { max-width: 460px; }
  .feature-grid, .about-grid, .download-panel { grid-template-columns: 1fr; }
  .method-list { grid-template-columns: 1fr 1fr; }
  .download-panel { padding: 48px 32px; }
  .section { padding: 80px 0; }
}
@media (max-width: 640px) {
  body { font-size: 16px; }
  .nav-links { display: none; }
  .method-list { grid-template-columns: 1fr; }
  .sm-only { display: inline; }
  .copyright { text-align: left; }
  .dl-grid { grid-template-columns: 1fr 1fr; gap: 12px; }
  .section { padding: 64px 0; }
}

/* =========================================================
   主题系统：亮 / 暗
   —— 通过在 <html data-theme="dark"> 切换 CSS 变量实现
   ========================================================= */
:root {
  color-scheme: light;
  /* 组件变量（亮色默认值） */
  --nav-bg: rgba(255, 255, 255, 0.86);
  --card-bg: #ffffff;
  --marker-bg: #ffffff;
  --line-strong: #d5dbe5;
  --brand-rgb: 37, 99, 235;          /* 供 rgba(var(--brand-rgb), a) 使用 */
  --note-bg: #fff8ec;
  --note-line: #f0d9a8;
  --note-soft: #98a1b0;
  --tier-idle: #b6bec9;
  --fade-top: 238, 243, 254;         /* hero 底部渐变色（RGB 三元组） */
  --fade-base: 255, 255, 255;
  --panel-border: rgba(255, 255, 255, 0.12);
  --toast-bg: #101828;
  --badge-done-bg: #e7f7f0;
  --badge-done-fg: #047857;
  --badge-todo-bg: #f0f1f4;
  --badge-todo-fg: #667085;
  --card-hover-shadow: 0 26px 60px -16px rgba(16, 24, 40, 0.26);
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0a1120;
  --bg-soft: #0f1a2e;
  --ink: #e7ecf5;
  --ink-2: #c7d0e0;
  --muted: #93a0b6;
  --line: #1e2a42;
  --line-strong: #31415f;
  --brand: #4f83f2;
  --brand-deep: #6f9bff;
  --brand-soft: #1b2a4a;
  --brand-rgb: 96, 148, 255;
  --dark: #04080f;
  --nav-bg: rgba(10, 17, 32, 0.78);
  --card-bg: #101b31;
  --marker-bg: #0f1a2e;
  --note-bg: rgba(246, 166, 9, 0.08);
  --note-line: rgba(246, 166, 9, 0.35);
  --note-soft: #7f8ba0;
  --tier-idle: #5a6a84;
  --fade-top: 14, 24, 48;
  --fade-base: 10, 17, 32;
  --panel-border: rgba(255, 255, 255, 0.10);
  --toast-bg: #182136;
  --badge-done-bg: rgba(16, 185, 129, 0.16);
  --badge-done-fg: #3dd68c;
  --badge-todo-bg: rgba(148, 163, 184, 0.12);
  --badge-todo-fg: #a9b6c8;
  --card-hover-shadow: 0 26px 60px -14px rgba(0, 0, 0, 0.6);
  --shadow-md: 0 14px 34px -10px rgba(0, 0, 0, 0.55);
}

/* 把原先硬编码的浅色/深色值改为走变量，使两套主题都正确 */
body { transition: background-color 0.35s ease, color 0.35s ease; }
.site-nav { background: var(--nav-bg); }
.brand-mark { background: var(--card-bg); }
.card { background: var(--card-bg); }
.card:hover { border-color: var(--line-strong); }
.phone-card, .tier-step { background: var(--card-bg); }
.method-list li { background: var(--card-bg); }
.pc-note { background: var(--note-bg); border-color: var(--note-line); }
.hero-note { color: var(--note-soft); }
.tier-step { color: var(--tier-idle); }
.tl-marker { background: var(--marker-bg); }
.badge-done { color: var(--badge-done-fg); background: var(--badge-done-bg); }
.badge-todo { color: var(--badge-todo-fg); background: var(--badge-todo-bg); }
.toast { background: var(--toast-bg); }
.download-panel { border: 1px solid var(--panel-border); }
.btn-primary { box-shadow: 0 6px 18px -6px rgba(var(--brand-rgb), 0.55); }
.btn-ghost:hover { border-color: var(--line-strong); }
.hero::after {
  background: linear-gradient(to top, rgba(var(--fade-top), 0.92), rgba(var(--fade-base), 0));
}

/* ---------- 主题切换按钮 ---------- */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  padding: 0;
  flex: none;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--card-bg);
  color: var(--ink-2);
  cursor: pointer;
  transition: transform 0.25s ease, color 0.25s ease, border-color 0.25s ease,
    background-color 0.25s ease;
}
.theme-toggle:hover {
  color: var(--brand);
  border-color: var(--line-strong);
  transform: translateY(-1px);
}
.theme-toggle:active { transform: translateY(0) scale(0.94); }
.theme-toggle svg { width: 18px; height: 18px; }
html[data-theme="light"] .theme-toggle .icon-moon { display: none; }
html[data-theme="dark"] .theme-toggle .icon-sun { display: none; }

/* =========================================================
   动效层
   ========================================================= */
/* ---------- Hero 入场（首屏加载即播） ---------- */
@keyframes riseIn {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: none; }
}
@keyframes fadeScale {
  from { opacity: 0; transform: translateY(14px) scale(0.965); }
  to   { opacity: 1; transform: none; }
}
.hero-copy > * {
  opacity: 0;
  animation: riseIn 0.75s cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
}
.hero-copy .eyebrow    { animation-delay: 0.05s; }
.hero-copy h1          { animation-delay: 0.14s; }
.hero-copy .lead       { animation-delay: 0.24s; }
.hero-copy .hero-ctas  { animation-delay: 0.34s; }
.hero-copy .hero-note  { animation-delay: 0.46s; }
.hero-demo {
  opacity: 0;
  animation: fadeScale 0.85s cubic-bezier(0.22, 0.61, 0.36, 1) 0.22s forwards;
}

/* ---------- 滚动出现（顺次进入，更有节奏） ---------- */
.reveal {
  transition: opacity 0.7s cubic-bezier(0.22, 0.61, 0.36, 1),
    transform 0.7s cubic-bezier(0.22, 0.61, 0.36, 1);
}
.feature-grid > .reveal:nth-child(2) { transition-delay: 0.08s; }
.feature-grid > .reveal:nth-child(3) { transition-delay: 0.16s; }
.feature-grid > .reveal:nth-child(4) { transition-delay: 0.24s; }
.method-list > li.reveal:nth-child(2) { transition-delay: 0.08s; }
.method-list > li.reveal:nth-child(3) { transition-delay: 0.16s; }
.method-list > li.reveal:nth-child(4) { transition-delay: 0.24s; }
.timeline > .tl.reveal:nth-child(2) { transition-delay: 0.07s; }
.timeline > .tl.reveal:nth-child(3) { transition-delay: 0.14s; }
.timeline > .tl.reveal:nth-child(4) { transition-delay: 0.21s; }
.timeline > .tl.reveal:nth-child(5) { transition-delay: 0.28s; }
.about-grid > .reveal:nth-child(2) { transition-delay: 0.14s; }

/* ---------- Hero 背景浮动光斑 ---------- */
.hero { isolation: isolate; }
.hero-skyline {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  overflow: hidden;
}
.hero-grid { position: relative; z-index: 1; }
.hero-skyline::before,
.hero-skyline::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  filter: blur(14px);
}
.hero-skyline::before {
  width: 360px; height: 360px;
  left: -130px; top: -130px;
  background: radial-gradient(circle, rgba(var(--brand-rgb), 0.16), transparent 65%);
  animation: drift1 18s ease-in-out infinite alternate;
}
.hero-skyline::after {
  width: 300px; height: 300px;
  right: -110px; bottom: -80px;
  background: radial-gradient(circle, rgba(246, 166, 9, 0.12), transparent 65%);
  animation: drift2 22s ease-in-out infinite alternate;
}
@keyframes drift1 {
  from { transform: translate(0, 0) scale(1); }
  to   { transform: translate(70px, 46px) scale(1.15); }
}
@keyframes drift2 {
  from { transform: translate(0, 0) scale(1); }
  to   { transform: translate(-60px, -40px) scale(0.9); }
}

/* ---------- 悬停与持续动效 ---------- */
/* 主按钮：掠过光泽 + 呼吸阴影 */
.btn-primary { position: relative; overflow: hidden; }
.btn-primary::after {
  content: "";
  position: absolute;
  top: 0; left: 0;
  height: 100%; width: 55%;
  background: linear-gradient(105deg, transparent, rgba(255, 255, 255, 0.35), transparent);
  transform: translateX(-160%) skewX(-18deg);
  transition: transform 0.6s ease;
  pointer-events: none;
}
.btn-primary:hover::after { transform: translateX(230%) skewX(-18deg); }
.hero .btn-lg {
  animation: ctaPulse 2.8s ease-out infinite;
}
@keyframes ctaPulse {
  0%, 100% { box-shadow: 0 6px 18px -6px rgba(var(--brand-rgb), 0.55); }
  45%      { box-shadow: 0 6px 32px -2px rgba(var(--brand-rgb), 0.7); }
}
.btn-ghost svg, .btn-primary svg { transition: transform 0.25s ease; }
.btn-ghost:hover svg { transform: translateX(3px); }
.btn-primary:hover svg { transform: translateY(2px); }

/* 功能卡：图标活跃 + 悬停轻微浮起（已有 hover，补充图标动感） */
.feature .card-icon {
  transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1),
    box-shadow 0.35s ease;
}
.feature:hover .card-icon {
  transform: scale(1.08) rotate(-6deg);
}
.feature .card-icon svg { transition: transform 0.35s ease; }
.feature:hover .card-icon svg { transform: translateY(-1px); }

/* 引导机制编号微动 */
.method-list li { transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease, background-color 0.3s ease; }
.method-list li:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--line-strong);
}
.method-num { display: inline-block; }
.method-list li:hover .method-num { animation: numPop 0.4s ease; }
@keyframes numPop {
  0%   { transform: scale(1); }
  50%  { transform: scale(1.25); }
  100% { transform: scale(1); }
}

/* 时间线当前节点：呼吸光圈 */
.tl.is-current .tl-marker {
  animation: markerPulse 2.2s ease-in-out infinite;
}
@keyframes markerPulse {
  0%   { box-shadow: 0 0 0 0 rgba(var(--brand-rgb), 0.35); }
  70%  { box-shadow: 0 0 0 11px rgba(var(--brand-rgb), 0); }
  100% { box-shadow: 0 0 0 0 rgba(var(--brand-rgb), 0); }
}

/* 对话演示卡：在线指示灯呼吸 + 下载卡图标微弹 */
.pc-dot { animation: dotPulse 2s ease-in-out infinite; }
@keyframes dotPulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(52, 211, 153, 0.5); }
  55%      { box-shadow: 0 0 0 7px rgba(52, 211, 153, 0); }
}
.download-panel .dl-btn { position: relative; overflow: hidden; }
.download-panel .dl-btn .dl-icon { transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1); }
.download-panel .dl-btn:hover .dl-icon { transform: translateY(-3px) scale(1.06); }
.download-panel .dl-btn::after {
  content: "";
  position: absolute;
  top: 0; left: 0;
  height: 100%; width: 40%;
  background: linear-gradient(105deg, transparent, rgba(255, 255, 255, 0.07), transparent);
  transform: translateX(-160%) skewX(-18deg);
  transition: transform 0.65s ease;
  pointer-events: none;
}
.download-panel .dl-btn:hover::after { transform: translateX(300%) skewX(-18deg); }

/* 下载面板：缓慢扫过一层微光 */
.download-panel::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(115deg, transparent 42%, rgba(255, 255, 255, 0.05) 50%, transparent 58%);
  background-size: 260% 100%;
  animation: panelShine 9s ease-in-out infinite;
  pointer-events: none;
}
@keyframes panelShine {
  0%, 55% { background-position: 130% 0; }
  90%, 100% { background-position: -60% 0; }
}

/* 主张句强调字：下划线圈出 */
.statement-text .hl { position: relative; }
.statement-text .hl::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -2px;
  height: 8px;
  background: linear-gradient(90deg, transparent, rgba(var(--brand-rgb), 0.28), transparent);
  border-radius: 999px;
  transform: scaleX(0);
  transform-origin: center;
  transition: transform 0.7s ease 0.25s;
}
.statement .container.reveal.in .hl::after { transform: scaleX(1); }

/* ---------- 尊重系统「减少动态效果」 ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  .reveal { opacity: 1; transform: none; }
  .hero-copy > *, .hero-demo { opacity: 1; animation: none; }
  .btn-primary::after, .dl-btn::after, .download-panel::after,
  .hero-skyline::before, .hero-skyline::after { display: none; }
  html { scroll-behavior: auto; }
}

/* ---------- 小屏细节微调 ---------- */
@media (max-width: 640px) {
  .theme-toggle { width: 36px; height: 36px; }
  .hero-copy > *, .hero-demo { animation-duration: 0.5s; }
}

/* ---------- 演示卡：鼠标跟随 3D 翻动 ---------- */
.hero-demo { perspective: 1100px; }
.phone-card {
  position: relative;
  transform-style: preserve-3d;
  transition: box-shadow 0.35s ease;
}
/* 光标高光（位置由 JS 写入 --gx / --gy） */
.phone-card::after {
  content: "";
  position: absolute; inset: 0;
  border-radius: inherit;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.4s ease;
  background: radial-gradient(340px circle at var(--gx, 50%) var(--gy, 50%),
    rgba(255, 255, 255, 0.18), transparent 62%);
}
@media (hover: hover) and (pointer: fine) {
  .hero-demo:hover .phone-card {
    box-shadow: var(--card-hover-shadow);
    transform: translateY(-2px) scale(1.012);
  }
  .hero-demo:hover .phone-card::after { opacity: 1; }
}