/* ==========================================================================
   AI 编程培训获客站 — 全局样式
   手写 CSS，不依赖任何 CDN。国内加载稳定。
   ========================================================================== */

/* ---------- Design Tokens ---------- */
:root {
  --bg: #0a0e1a;
  --bg-soft: #101728;
  --bg-card: #151d31;
  --bg-card-hover: #1a2440;
  --border: #223050;
  --border-soft: #1a2540;

  --text: #eef2f9;
  --text-dim: #9aa8c4;
  --text-mute: #6b7a99;

  --brand: #4d7cff;
  --brand-light: #7aa0ff;
  --brand-dark: #2f5ce0;
  --accent: #22d3a6;
  --warn: #ffb84d;

  --grad: linear-gradient(135deg, #4d7cff 0%, #22d3a6 100%);
  --grad-text: linear-gradient(120deg, #7aa0ff 0%, #22d3a6 100%);

  --radius: 14px;
  --radius-lg: 20px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.32);
  --shadow-lg: 0 18px 56px rgba(0, 0, 0, 0.45);

  --wrap: 1160px;
  --nav-h: 64px;
}

/* ---------- Reset ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: var(--brand-light);
  text-decoration: none;
  transition: color 0.18s ease;
}

a:hover {
  color: var(--accent);
}

h1,
h2,
h3,
h4 {
  margin: 0 0 0.6em;
  line-height: 1.28;
  font-weight: 700;
  letter-spacing: -0.01em;
}

p {
  margin: 0 0 1em;
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

button {
  font: inherit;
  cursor: pointer;
}

/* Visible focus for keyboard users (a11y) */
:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
  border-radius: 6px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: 50%;
  transform: translateX(-50%) translateY(-200%);
  top: 8px;
  z-index: 200;
  background: var(--brand);
  color: #fff;
  padding: 10px 20px;
  border-radius: 8px;
  font-weight: 600;
  transition: transform 0.2s ease;
}

.skip-link:focus {
  transform: translateX(-50%) translateY(0);
  color: #fff;
}

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

.section {
  padding: 88px 0;
  position: relative;
}

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

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 52px;
}

.section-head h2 {
  font-size: clamp(1.6rem, 3.4vw, 2.35rem);
  margin-bottom: 14px;
}

.section-head p {
  color: var(--text-dim);
  font-size: 1.05rem;
  margin: 0;
}

.eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}

.gradient-text {
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

/* ---------- Nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-h);
  display: flex;
  align-items: center;
  background: rgba(10, 14, 26, 0.86);
  backdrop-filter: saturate(160%) blur(14px);
  -webkit-backdrop-filter: saturate(160%) blur(14px);
  border-bottom: 1px solid var(--border-soft);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.06rem;
  color: var(--text);
  letter-spacing: -0.02em;
  flex-shrink: 0;
}

.brand:hover {
  color: var(--text);
}

.brand__mark {
  width: 30px;
  height: 30px;
  border-radius: 9px;
  background: var(--grad);
  display: grid;
  place-items: center;
  font-size: 0.9rem;
  font-weight: 800;
  color: #06121f;
  flex-shrink: 0;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 30px;
  margin-left: auto;
}

.nav__links a {
  color: var(--text-dim);
  font-size: 0.94rem;
  font-weight: 500;
  white-space: nowrap;
}

.nav__links a:hover,
.nav__links a[aria-current="page"] {
  color: var(--text);
}

.nav__cta {
  flex-shrink: 0;
}

.nav__toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 8px;
  padding: 6px 10px;
  line-height: 1;
  font-size: 1.2rem;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: 11px;
  border: 1px solid transparent;
  font-weight: 650;
  font-size: 0.98rem;
  text-align: center;
  transition: transform 0.16s ease, box-shadow 0.16s ease,
    background 0.16s ease, border-color 0.16s ease;
  white-space: nowrap;
}

.btn--primary {
  background: var(--grad);
  color: #06121f;
  box-shadow: 0 8px 24px rgba(77, 124, 255, 0.28);
}

.btn--primary:hover {
  color: #06121f;
  transform: translateY(-2px);
  box-shadow: 0 14px 34px rgba(77, 124, 255, 0.42);
}

.btn--ghost {
  background: rgba(255, 255, 255, 0.04);
  border-color: var(--border);
  color: var(--text);
}

.btn--ghost:hover {
  color: var(--text);
  border-color: var(--brand);
  background: rgba(77, 124, 255, 0.12);
  transform: translateY(-2px);
}

.btn--sm {
  padding: 9px 18px;
  font-size: 0.9rem;
  border-radius: 9px;
}

.btn--lg {
  padding: 16px 34px;
  font-size: 1.06rem;
}

.btn--block {
  width: 100%;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 96px 0 84px;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -280px;
  left: 50%;
  transform: translateX(-50%);
  width: 1100px;
  height: 720px;
  background: radial-gradient(
    circle at center,
    rgba(77, 124, 255, 0.22) 0%,
    rgba(34, 211, 166, 0.08) 42%,
    transparent 68%
  );
  pointer-events: none;
  z-index: 0;
}

.hero__inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 56px;
  align-items: center;
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 16px;
  border-radius: 999px;
  border: 1px solid rgba(34, 211, 166, 0.32);
  background: rgba(34, 211, 166, 0.09);
  color: var(--accent);
  font-size: 0.86rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(2rem, 4.6vw, 3.15rem);
  line-height: 1.2;
  margin-bottom: 22px;
  letter-spacing: -0.025em;
}

.hero__lead {
  font-size: 1.1rem;
  color: var(--text-dim);
  max-width: 560px;
  margin-bottom: 30px;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 34px;
}

.hero__proof {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 12px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 7px 14px;
  border-radius: 999px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--text-dim);
  font-weight: 500;
}

.chip strong {
  color: var(--text);
  font-weight: 650;
}

/* ---------- Lead form card ---------- */
.form-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 30px 28px;
  box-shadow: var(--shadow-lg);
  position: relative;
}

.form-card__title {
  font-size: 1.25rem;
  margin-bottom: 6px;
}

.form-card__sub {
  color: var(--text-dim);
  font-size: 0.92rem;
  margin-bottom: 22px;
}

.gift-list {
  display: grid;
  gap: 9px;
  margin-bottom: 24px;
  padding: 16px;
  background: rgba(77, 124, 255, 0.07);
  border: 1px solid rgba(77, 124, 255, 0.18);
  border-radius: var(--radius);
}

.gift-list li {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-size: 0.92rem;
  color: var(--text-dim);
  line-height: 1.6;
}

.gift-list li::before {
  content: "✓";
  color: var(--accent);
  font-weight: 800;
  flex-shrink: 0;
}

.field {
  margin-bottom: 16px;
}

.field label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 7px;
}

.field .req {
  color: var(--warn);
  margin-left: 2px;
}

.field input[type="text"],
.field input[type="tel"],
.field input[type="email"],
.field select,
.field textarea {
  width: 100%;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #0c1220;
  color: var(--text);
  font-size: 0.98rem;
  font-family: inherit;
  transition: border-color 0.16s ease, box-shadow 0.16s ease;
}

.field textarea {
  resize: vertical;
  min-height: 82px;
}

.field input::placeholder,
.field textarea::placeholder {
  color: var(--text-mute);
}

.field input:focus,
.field select:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(77, 124, 255, 0.18);
}

.field select {
  appearance: none;
  background-image: url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='%239aa8c4' d='M6 8 0 0h12z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 36px;
}

.radio-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.radio-pill {
  position: relative;
}

.radio-pill input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
}

.radio-pill span {
  display: inline-block;
  padding: 9px 16px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: #0c1220;
  color: var(--text-dim);
  font-size: 0.9rem;
  cursor: pointer;
  transition: all 0.16s ease;
  user-select: none;
}

.radio-pill input:checked + span {
  border-color: var(--brand);
  background: rgba(77, 124, 255, 0.16);
  color: var(--text);
  font-weight: 600;
}

.radio-pill input:focus-visible + span {
  outline: 3px solid var(--accent);
  outline-offset: 2px;
}

.form-note {
  font-size: 0.82rem;
  color: var(--text-mute);
  margin: 14px 0 0;
  text-align: center;
  line-height: 1.6;
}

.field-error {
  color: #ff8080;
  font-size: 0.82rem;
  margin-top: 6px;
  display: none;
}

.field-error.show {
  display: block;
}

.field input[aria-invalid="true"],
.field select[aria-invalid="true"] {
  border-color: #ff8080;
}

/* ---------- Cards / grids ---------- */
.grid {
  display: grid;
  gap: 22px;
}

.grid--2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid--3 {
  grid-template-columns: repeat(3, 1fr);
}

.grid--4 {
  grid-template-columns: repeat(4, 1fr);
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 26px 24px;
  transition: transform 0.18s ease, border-color 0.18s ease,
    background 0.18s ease;
}

.card:hover {
  transform: translateY(-3px);
  border-color: rgba(77, 124, 255, 0.42);
  background: var(--bg-card-hover);
}

.card__icon {
  font-size: 1.7rem;
  line-height: 1;
  margin-bottom: 14px;
  display: block;
}

.card h3 {
  font-size: 1.08rem;
  margin-bottom: 8px;
}

.card p {
  color: var(--text-dim);
  font-size: 0.94rem;
  margin: 0;
}

.card--pain {
  border-left: 3px solid var(--warn);
}

/* Step cards */
.step {
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 24px 26px;
}

.step__num {
  position: absolute;
  top: -16px;
  left: 24px;
  width: 40px;
  height: 40px;
  border-radius: 11px;
  background: var(--grad);
  color: #06121f;
  display: grid;
  place-items: center;
  font-weight: 800;
  font-size: 1.02rem;
  box-shadow: 0 6px 18px rgba(77, 124, 255, 0.3);
}

.step h3 {
  font-size: 1.1rem;
  margin: 14px 0 8px;
}

.step p {
  color: var(--text-dim);
  font-size: 0.94rem;
  margin: 0;
}

/* Plan cards */
.plan {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 26px;
  display: flex;
  flex-direction: column;
  transition: transform 0.18s ease, border-color 0.18s ease;
}

.plan:hover {
  transform: translateY(-4px);
  border-color: rgba(34, 211, 166, 0.4);
}

.plan--featured {
  border-color: rgba(77, 124, 255, 0.5);
  background: linear-gradient(
    170deg,
    rgba(77, 124, 255, 0.1) 0%,
    var(--bg-card) 55%
  );
}

.plan__tag {
  align-self: flex-start;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  padding: 4px 11px;
  border-radius: 999px;
  background: rgba(77, 124, 255, 0.2);
  color: var(--brand-light);
  margin-bottom: 14px;
}

.plan__icon {
  font-size: 1.8rem;
  margin-bottom: 12px;
}

.plan h3 {
  font-size: 1.2rem;
  margin-bottom: 4px;
}

.plan__for {
  color: var(--accent);
  font-size: 0.87rem;
  font-weight: 600;
  margin-bottom: 18px;
}

.plan ul {
  display: grid;
  gap: 10px;
  margin-bottom: 22px;
}

.plan ul li {
  display: flex;
  gap: 9px;
  font-size: 0.93rem;
  color: var(--text-dim);
  line-height: 1.6;
}

.plan ul li::before {
  content: "▸";
  color: var(--brand-light);
  flex-shrink: 0;
}

.plan .btn {
  margin-top: auto;
}

/* ---------- Stats ---------- */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.stat {
  text-align: center;
  padding: 26px 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.stat__num {
  font-size: clamp(1.7rem, 3.6vw, 2.4rem);
  font-weight: 800;
  line-height: 1.1;
  background: var(--grad-text);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -0.02em;
}

.stat__label {
  color: var(--text-dim);
  font-size: 0.9rem;
  margin-top: 6px;
}

/* ---------- Logo / partner wall ---------- */
.logo-wall {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.logo-pill {
  padding: 11px 20px;
  border-radius: 11px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text-dim);
  font-size: 0.94rem;
  font-weight: 550;
  transition: all 0.18s ease;
}

.logo-pill:hover {
  border-color: rgba(77, 124, 255, 0.42);
  color: var(--text);
  transform: translateY(-2px);
}

.wall-note {
  text-align: center;
  color: var(--text-mute);
  font-size: 0.84rem;
  margin-top: 26px;
}

/* ---------- FAQ ---------- */
.faq {
  max-width: 820px;
  margin: 0 auto;
  display: grid;
  gap: 12px;
}

.faq__item {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.faq__q {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 19px 22px;
  background: none;
  border: 0;
  color: var(--text);
  font-size: 1rem;
  font-weight: 600;
  text-align: left;
  line-height: 1.5;
}

.faq__q:hover {
  color: var(--brand-light);
}

.faq__icon {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  display: grid;
  place-items: center;
  color: var(--brand-light);
  font-size: 1.2rem;
  transition: transform 0.22s ease;
}

.faq__q[aria-expanded="true"] .faq__icon {
  transform: rotate(45deg);
}

.faq__a {
  padding: 0 22px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.26s ease, padding 0.26s ease;
}

.faq__a p {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin: 0 0 18px;
}

.faq__item.open .faq__a {
  max-height: 420px;
}

/* ---------- Split / feature rows ---------- */
.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 52px;
  align-items: center;
}

.split__media {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--shadow);
}

.bullets {
  display: grid;
  gap: 16px;
}

.bullets li {
  display: flex;
  gap: 13px;
  align-items: flex-start;
}

.bullets .b-ico {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 8px;
  background: rgba(34, 211, 166, 0.14);
  color: var(--accent);
  display: grid;
  place-items: center;
  font-size: 0.85rem;
  font-weight: 800;
  margin-top: 3px;
}

.bullets strong {
  display: block;
  font-size: 1rem;
  margin-bottom: 2px;
}

.bullets span.b-text {
  color: var(--text-dim);
  font-size: 0.93rem;
  line-height: 1.65;
}

/* ---------- Timeline (about page) ---------- */
.timeline {
  position: relative;
  padding-left: 30px;
  display: grid;
  gap: 26px;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 7px;
  top: 6px;
  bottom: 6px;
  width: 2px;
  background: linear-gradient(
    to bottom,
    var(--brand),
    rgba(34, 211, 166, 0.3)
  );
}

.timeline__item {
  position: relative;
}

.timeline__item::before {
  content: "";
  position: absolute;
  left: -30px;
  top: 8px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg);
  border: 3px solid var(--brand);
}

.timeline__year {
  color: var(--accent);
  font-weight: 700;
  font-size: 0.9rem;
  letter-spacing: 0.04em;
}

.timeline__item h3 {
  font-size: 1.05rem;
  margin: 4px 0 6px;
}

.timeline__item p {
  color: var(--text-dim);
  font-size: 0.94rem;
  margin: 0;
}

/* ---------- CTA band ---------- */
.cta-band {
  position: relative;
  padding: 76px 0;
  text-align: center;
  overflow: hidden;
  background: linear-gradient(
    135deg,
    rgba(77, 124, 255, 0.14),
    rgba(34, 211, 166, 0.1)
  );
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.cta-band h2 {
  font-size: clamp(1.6rem, 3.6vw, 2.3rem);
  margin-bottom: 14px;
}

.cta-band p {
  color: var(--text-dim);
  max-width: 560px;
  margin: 0 auto 28px;
  font-size: 1.04rem;
}

/* ---------- Callout ---------- */
.callout {
  background: rgba(34, 211, 166, 0.07);
  border: 1px solid rgba(34, 211, 166, 0.24);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  padding: 20px 22px;
  color: var(--text-dim);
  font-size: 0.95rem;
}

.callout strong {
  color: var(--text);
}

/* ---------- QR block (campus) ---------- */
.qr-box {
  display: flex;
  align-items: center;
  gap: 26px;
  background: var(--bg-card);
  border: 1px dashed var(--border);
  border-radius: var(--radius-lg);
  padding: 26px;
}

.qr-ph {
  flex-shrink: 0;
  width: 128px;
  height: 128px;
  border-radius: 12px;
  background: repeating-conic-gradient(
      from 0deg,
      #0c1220 0deg 90deg,
      #16203a 90deg 180deg
    )
    0 0 / 16px 16px;
  border: 1px solid var(--border);
  display: grid;
  place-items: center;
  color: var(--text-mute);
  font-size: 0.78rem;
  text-align: center;
  padding: 8px;
}

/* ---------- Thanks page ---------- */
.thanks {
  min-height: calc(100vh - var(--nav-h));
  display: grid;
  place-items: center;
  padding: 60px 0;
  position: relative;
  overflow: hidden;
}

.thanks::before {
  content: "";
  position: absolute;
  inset: auto auto auto 50%;
  top: -200px;
  transform: translateX(-50%);
  width: 900px;
  height: 600px;
  background: radial-gradient(
    circle,
    rgba(34, 211, 166, 0.16),
    transparent 66%
  );
  pointer-events: none;
}

.thanks__card {
  position: relative;
  z-index: 1;
  max-width: 620px;
  text-align: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 46px 36px;
  box-shadow: var(--shadow-lg);
}

.thanks__mark {
  width: 74px;
  height: 74px;
  margin: 0 auto 22px;
  border-radius: 50%;
  background: var(--grad);
  display: grid;
  place-items: center;
  font-size: 2.1rem;
  color: #06121f;
}

.next-steps {
  text-align: left;
  display: grid;
  gap: 14px;
  margin: 28px 0;
  padding: 22px;
  background: rgba(77, 124, 255, 0.07);
  border: 1px solid rgba(77, 124, 255, 0.18);
  border-radius: var(--radius);
}

.next-steps li {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  font-size: 0.95rem;
  color: var(--text-dim);
}

.next-steps .n {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  border-radius: 7px;
  background: rgba(77, 124, 255, 0.22);
  color: var(--brand-light);
  display: grid;
  place-items: center;
  font-size: 0.8rem;
  font-weight: 700;
}

/* ---------- Page header (sub pages) ---------- */
.page-head {
  padding: 66px 0 46px;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--border-soft);
}

.page-head::before {
  content: "";
  position: absolute;
  top: -220px;
  left: 50%;
  transform: translateX(-50%);
  width: 900px;
  height: 520px;
  background: radial-gradient(
    circle,
    rgba(77, 124, 255, 0.16),
    transparent 66%
  );
  pointer-events: none;
}

.page-head__inner {
  position: relative;
  z-index: 1;
  max-width: 780px;
}

.page-head h1 {
  font-size: clamp(1.8rem, 4vw, 2.7rem);
  margin-bottom: 16px;
}

.page-head p {
  color: var(--text-dim);
  font-size: 1.06rem;
  margin: 0;
}

/* ---------- Footer ---------- */
.footer {
  background: #070a12;
  border-top: 1px solid var(--border-soft);
  padding: 52px 0 30px;
  font-size: 0.92rem;
}

.footer__grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 36px;
}

.footer h4 {
  font-size: 0.88rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-mute);
  margin-bottom: 14px;
}

.footer__links {
  display: grid;
  gap: 10px;
}

.footer__links a {
  color: var(--text-dim);
  font-size: 0.93rem;
}

.footer__links a:hover {
  color: var(--accent);
}

.footer__about p {
  color: var(--text-mute);
  max-width: 380px;
  margin: 12px 0 0;
  font-size: 0.9rem;
  line-height: 1.7;
}

.footer__bottom {
  border-top: 1px solid var(--border-soft);
  padding-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  justify-content: space-between;
  color: var(--text-mute);
  font-size: 0.85rem;
}

/* ---------- Reveal on scroll ----------
   渐进增强：默认可见。只有 JS 成功接管后（html.js-reveal）才隐藏并做动画。
   这样 JS 失败 / 被拦截时内容照常显示，不会白屏。
------------------------------------------ */
.js-reveal .reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

.js-reveal .reveal.in {
  opacity: 1;
  transform: none;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .js-reveal .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    transition-duration: 0.001ms !important;
  }
}

/* ---------- Responsive ---------- */
@media (max-width: 1000px) {
  .hero__inner {
    grid-template-columns: 1fr;
    gap: 44px;
  }
  .split {
    grid-template-columns: 1fr;
    gap: 34px;
  }
  .grid--4 {
    grid-template-columns: repeat(2, 1fr);
  }
  .stats {
    grid-template-columns: repeat(2, 1fr);
  }
  .footer__grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 760px) {
  .section {
    padding: 62px 0;
  }
  .hero {
    padding: 60px 0 56px;
  }
  .nav__links {
    display: none;
  }
  .nav__links.open {
    display: flex;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--bg-soft);
    border-bottom: 1px solid var(--border);
    padding: 8px 24px 16px;
  }
  .nav__links.open a {
    padding: 12px 0;
    width: 100%;
    border-bottom: 1px solid var(--border-soft);
  }
  .nav__toggle {
    display: block;
  }
  .nav__cta {
    display: none;
  }
  .grid--2,
  .grid--3,
  .grid--4 {
    grid-template-columns: 1fr;
  }
  .footer__grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }
  .qr-box {
    flex-direction: column;
    text-align: center;
  }
  .form-card {
    padding: 24px 20px;
  }
  .hero__actions .btn {
    width: 100%;
  }
}

@media (max-width: 420px) {
  .stats {
    grid-template-columns: 1fr;
  }
}