/* ============================================================
   词鲸英语官网 · style.css
   配色：紫(#8B5CF6) + 粉(#EC4899) + 暖黄(#FEF3C7)
   风格：卡通 + 科技
   ============================================================ */

/* ---------- 基础重置 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC",
    "Microsoft YaHei", "Helvetica Neue", "Hiragino Sans GB", Arial,
    sans-serif;
  font-size: 16px;
  line-height: 1.65;
  color: #1F2937;
  background: #FAFAFC;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
}

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

input, select, textarea {
  font-family: inherit;
  font-size: inherit;
}

/* ---------- 设计变量 ---------- */
:root {
  --c-primary: #6366F1;
  --c-violet:  #8B5CF6;
  --c-pink:    #EC4899;
  --c-orange:  #FB923C;
  --c-yellow:  #FEF3C7;
  --c-mint:    #10B981;
  --c-blue:    #3B82F6;

  --c-text:    #1F2937;
  --c-sub:     #4B5563;
  --c-muted:   #9CA3AF;
  --c-line:    #E5E7EB;

  --c-bg:      #FAFAFC;
  --c-bg-alt:  #F3F0FF;
  --c-bg-dark: #1F1B3D;

  --shadow-sm: 0 4px 12px rgba(99, 102, 241, 0.06);
  --shadow-md: 0 12px 30px rgba(99, 102, 241, 0.08);
  --shadow-lg: 0 24px 60px rgba(99, 102, 241, 0.14);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;

  --grad-brand: linear-gradient(135deg, #6366F1 0%, #8B5CF6 50%, #EC4899 100%);
  --grad-soft:  linear-gradient(135deg, #EEF2FF 0%, #FCE7F3 100%);
}

/* ---------- 通用 ---------- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 600;
  font-size: 15px;
  transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
  white-space: nowrap;
}

.btn-lg {
  padding: 16px 30px;
  font-size: 16px;
}

.btn-primary {
  background: var(--grad-brand);
  color: #fff;
  box-shadow: 0 8px 20px rgba(139, 92, 246, .35);
}
.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 30px rgba(139, 92, 246, .45);
}

.btn-ghost {
  background: #fff;
  color: var(--c-text);
  border: 1.5px solid var(--c-line);
}
.btn-ghost:hover {
  border-color: var(--c-violet);
  color: var(--c-violet);
}

.section {
  padding: 96px 0;
  position: relative;
}
.section-alt {
  background: var(--c-bg-alt);
}
.section-dark {
  background: linear-gradient(135deg, #2D1B69 0%, #1F1B3D 100%);
  color: #fff;
}

.section-head {
  text-align: center;
  max-width: 720px;
  margin: 0 auto 56px;
}

.badge {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: rgba(139, 92, 246, .1);
  color: var(--c-violet);
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 16px;
}
.badge-light {
  background: rgba(255, 255, 255, .12);
  color: #fff;
}

.section-title {
  font-size: 40px;
  font-weight: 800;
  line-height: 1.25;
  margin: 0 0 16px;
  letter-spacing: -0.5px;
}
.section-title.light { color: #fff; }
.section-sub {
  font-size: 17px;
  color: var(--c-sub);
  margin: 0;
}
.section-sub.light { color: rgba(255,255,255,.7); }

/* ---------- 顶部导航 ---------- */
.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, .85);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .25s ease, box-shadow .25s ease;
}
.navbar.scrolled {
  border-bottom-color: var(--c-line);
  box-shadow: 0 4px 12px rgba(0,0,0,.04);
}

.nav-inner {
  display: flex;
  align-items: center;
  height: 72px;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.brand-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.brand-name {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -.5px;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  -webkit-text-fill-color: transparent;
}

.nav-menu {
  display: flex;
  gap: 28px;
  margin: 0 auto;
  padding: 0;
  list-style: none;
}
.nav-menu a {
  font-size: 15px;
  font-weight: 500;
  color: var(--c-sub);
  position: relative;
  padding: 6px 0;
  transition: color .2s;
}
.nav-menu a:hover { color: var(--c-violet); }
.nav-menu a::after {
  content: "";
  position: absolute;
  bottom: 0; left: 50%;
  width: 0; height: 2px;
  background: var(--grad-brand);
  border-radius: 2px;
  transition: width .25s, left .25s;
}
.nav-menu a:hover::after { width: 100%; left: 0; }

.nav-cta { padding: 10px 20px; font-size: 14px; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 6px;
}
.nav-toggle span {
  width: 22px; height: 2px;
  background: var(--c-text);
  border-radius: 2px;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: 80px 0 120px;
  overflow: hidden;
  background: linear-gradient(180deg, #F5F3FF 0%, #FCF7FF 50%, #FAFAFC 100%);
}

.bg-blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: .55;
  pointer-events: none;
}
.blob-1 {
  width: 480px; height: 480px;
  top: -160px; left: -120px;
  background: #C7B8FF;
}
.blob-2 {
  width: 520px; height: 520px;
  top: 80px; right: -160px;
  background: #FBC4D6;
}
.blob-3 {
  width: 600px; height: 600px;
  bottom: -200px; left: 30%;
  background: #6D4DFF;
  opacity: .35;
}

.bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(99,102,241,.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99,102,241,.07) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
  -webkit-mask-image: radial-gradient(ellipse at center, #000 30%, transparent 75%);
  pointer-events: none;
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  align-items: center;
  gap: 60px;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: 999px;
  background: #fff;
  border: 1px solid var(--c-line);
  font-size: 13px;
  color: var(--c-sub);
  font-weight: 500;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}
.hero-tag .dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--c-mint);
  box-shadow: 0 0 0 4px rgba(16, 185, 129, .2);
}

.hero-title {
  font-size: 60px;
  line-height: 1.15;
  letter-spacing: -1.5px;
  font-weight: 800;
  margin: 0 0 20px;
}

.hero-subtitle {
  font-size: 18px;
  color: var(--c-sub);
  line-height: 1.7;
  margin: 0 0 36px;
  max-width: 540px;
}

.hero-buttons {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.hero-trust {
  display: flex;
  align-items: center;
  gap: 14px;
}
.trust-avatars { display: inline-flex; }
.av {
  width: 36px; height: 36px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #fff;
  border: 2.5px solid #fff;
  margin-left: -10px;
}
.av:first-child { margin-left: 0; }
.av-1 { background: #FB923C; }
.av-2 { background: #EC4899; }
.av-3 { background: #8B5CF6; }
.av-4 { background: #10B981; }
.trust-text { font-size: 14px; color: var(--c-sub); }
.trust-text strong { color: var(--c-text); font-weight: 700; }

/* hero 视觉卡片 */
.hero-visual {
  position: relative;
  height: 460px;
}
.hero-card {
  position: absolute;
  background: #fff;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}

.card-main {
  inset: 30px 0 auto 30px;
  width: 340px;
  padding: 22px;
  transform: rotate(-3deg);
  animation: float 6s ease-in-out infinite;
}
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-bottom: 12px;
  margin-bottom: 14px;
  border-bottom: 1px dashed var(--c-line);
}
.card-dots {
  display: inline-flex;
  gap: 5px;
}
.card-dots span {
  width: 10px; height: 10px;
  border-radius: 50%;
}
.card-dots span:nth-child(1) { background: #FB923C; }
.card-dots span:nth-child(2) { background: #FDE68A; }
.card-dots span:nth-child(3) { background: #10B981; }
.card-title {
  font-size: 12px;
  color: var(--c-muted);
  font-weight: 600;
}

.flashcard {
  height: 170px;
  border-radius: var(--radius-md);
  background: var(--grad-soft);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}
.flashcard-inner { text-align: center; padding: 20px; }
.flash-en {
  font-size: 36px;
  font-weight: 800;
  color: var(--c-violet);
  margin-bottom: 8px;
}
.flash-phonetic {
  color: var(--c-sub);
  font-size: 16px;
  margin-bottom: 12px;
}
.flash-hint { font-size: 12px; color: var(--c-muted); }

.progress-row {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.progress-label {
  font-size: 12px;
  color: var(--c-sub);
  font-weight: 600;
}
.progress-bar {
  height: 8px;
  background: var(--c-bg-alt);
  border-radius: 999px;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: var(--grad-brand);
  border-radius: 999px;
}

.card-mini {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
}
.card-mini-1 {
  top: 0; right: 20px;
  animation: floatAlt 7s ease-in-out infinite;
}
.card-mini-2 {
  bottom: 30px; left: 0;
  animation: float 8s ease-in-out infinite;
}
.mini-icon {
  width: 40px; height: 40px;
  border-radius: 12px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}
.mini-title { font-weight: 700; font-size: 15px; }
.mini-sub { font-size: 12px; color: var(--c-muted); }

@keyframes float {
  0%, 100% { transform: translateY(0) rotate(-3deg); }
  50%      { transform: translateY(-12px) rotate(-3deg); }
}
@keyframes floatAlt {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-10px); }
}

/* ---------- 数据条 ---------- */
.stats {
  background: #fff;
  border-top: 1px solid var(--c-line);
  border-bottom: 1px solid var(--c-line);
  padding: 40px 0;
}
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}
.stat-num {
  font-size: 42px;
  font-weight: 800;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  -webkit-text-fill-color: transparent;
  line-height: 1;
}
.stat-label {
  margin-top: 8px;
  font-size: 14px;
  color: var(--c-sub);
}

/* ---------- 学习特色 ---------- */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 22px;
}
.feature-card {
  padding: 28px;
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  transition: transform .25s, box-shadow .25s, border-color .25s;
}
.feature-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(139, 92, 246, .25);
}
.feature-icon {
  width: 64px; height: 64px;
  border-radius: 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  box-shadow: 0 6px 16px rgba(0,0,0,.05);
}
.feature-card h3 {
  font-size: 20px;
  font-weight: 700;
  margin: 0 0 10px;
}
.feature-card p {
  margin: 0;
  font-size: 14.5px;
  color: var(--c-sub);
  line-height: 1.7;
}

/* ---------- 适用人群 ---------- */
.stages-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 26px;
}
.stage-card {
  padding: 36px 28px;
  border-radius: var(--radius-lg);
  background: #fff;
  position: relative;
  overflow: hidden;
  border: 1px solid var(--c-line);
  transition: transform .25s, box-shadow .25s;
}
.stage-card::before {
  content: "";
  position: absolute;
  inset: -50px -50px auto auto;
  width: 200px; height: 200px;
  border-radius: 50%;
  filter: blur(40px);
  opacity: .6;
}
.stage-primary::before  { background: #FEF3C7; }
.stage-junior::before   { background: #DBEAFE; }
.stage-high::before     { background: #FCE7F3; }

.stage-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
}
.stage-emoji {
  font-size: 48px;
  margin-bottom: 16px;
}
.stage-card h3 {
  font-size: 22px;
  font-weight: 700;
  margin: 0 0 12px;
}
.stage-desc {
  color: var(--c-sub);
  margin: 0 0 20px;
}
.stage-list {
  list-style: none;
  padding: 0;
  margin: 0 0 24px;
}
.stage-list li {
  padding: 6px 0;
  font-size: 14.5px;
  color: var(--c-text);
  border-bottom: 1px dashed var(--c-line);
}
.stage-list li:last-child { border-bottom: none; }

.stage-tag {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--c-bg-alt);
  color: var(--c-violet);
  font-weight: 700;
  font-size: 13px;
}

/* ---------- 学习流程 ---------- */
.process-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  align-items: center;
}
.process-step {
  text-align: center;
  padding: 20px;
}
.process-num {
  font-size: 44px;
  font-weight: 800;
  background: var(--grad-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  -webkit-text-fill-color: transparent;
  line-height: 1;
  margin-bottom: 12px;
}
.process-step h3 {
  font-size: 18px;
  font-weight: 700;
  margin: 0 0 8px;
}
.process-step p {
  margin: 0;
  font-size: 14px;
  color: var(--c-sub);
  line-height: 1.65;
}
.process-line {
  height: 2px;
  background: repeating-linear-gradient(90deg, var(--c-violet) 0 6px, transparent 6px 12px);
  margin-top: 30px;
}

/* ---------- 为什么选我们 ---------- */
.why-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 24px;
}
.why-item {
  /* 3 列布局：(100% - 2 个 gap) / 3 */
  flex: 0 0 calc((100% - 48px) / 3);
  box-sizing: border-box;

  padding: 32px 26px;
  background: rgba(255, 255, 255, .06);
  border: 1px solid rgba(255, 255, 255, .1);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
  transition: transform .25s, background .25s;
}
.why-item:hover {
  transform: translateY(-4px);
  background: rgba(255, 255, 255, .1);
}
.why-num {
  display: inline-block;
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 1px;
  color: var(--c-pink);
  background: rgba(236, 72, 153, .15);
  padding: 4px 12px;
  border-radius: 999px;
  margin-bottom: 16px;
}
.why-item h3 {
  font-size: 20px;
  font-weight: 700;
  margin: 0 0 10px;
  color: #fff;
}
.why-item p {
  margin: 0;
  color: rgba(255,255,255,.7);
  font-size: 14.5px;
  line-height: 1.7;
}

/* ---------- 学员评价 ---------- */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.testimonial-card {
  padding: 32px 28px;
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  transition: transform .25s, box-shadow .25s;
}
.testimonial-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.stars {
  color: #FBBF24;
  font-size: 18px;
  letter-spacing: 2px;
  margin-bottom: 16px;
}
.testimonial-card p {
  font-size: 15.5px;
  line-height: 1.75;
  color: var(--c-text);
  margin: 0 0 22px;
}
.quote-author {
  display: flex;
  align-items: center;
  gap: 12px;
}
.quote-avatar {
  width: 44px; height: 44px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 18px;
}
.quote-name {
  font-weight: 700;
  font-size: 15px;
}
.quote-role {
  font-size: 13px;
  color: var(--c-muted);
}

/* ---------- FAQ ---------- */
.faq-wrap { max-width: 800px; margin: 0 auto; }
.faq-list { display: flex; flex-direction: column; gap: 12px; }

.faq-item {
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color .2s, box-shadow .2s;
}
.faq-item[open] { border-color: rgba(139, 92, 246, .25); box-shadow: var(--shadow-sm); }
.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 20px 24px;
  font-size: 16.5px;
  font-weight: 600;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  color: var(--c-text);
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-icon {
  color: var(--c-violet);
  transition: transform .25s;
  flex-shrink: 0;
}
.faq-item[open] .faq-icon { transform: rotate(180deg); }
.faq-content {
  padding: 0 24px 22px;
  font-size: 15px;
  color: var(--c-sub);
  line-height: 1.75;
}

/* ---------- CTA ---------- */
.cta {
  padding: 96px 0;
  background: var(--grad-soft);
}

.cta-inner {
  max-width: 880px;
  margin: 0 auto;
  text-align: center;
}
.cta-title {
  font-size: 40px;
  font-weight: 800;
  margin: 0 0 14px;
}
.cta-sub {
  font-size: 17px;
  color: var(--c-sub);
  margin: 0 0 40px;
}

.cta-form {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr auto;
  gap: 12px;
  background: #fff;
  padding: 18px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  margin-bottom: 16px;
  text-align: left;
}
.cta-field { display: flex; flex-direction: column; gap: 6px; }
.cta-field label {
  font-size: 12px;
  color: var(--c-muted);
  font-weight: 600;
  padding-left: 4px;
}
.cta-field input,
.cta-field select {
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--c-line);
  background: #FAFAFC;
  font-size: 14.5px;
  color: var(--c-text);
  outline: none;
  transition: border-color .2s, background .2s;
}
.cta-field input:focus,
.cta-field select:focus {
  border-color: var(--c-violet);
  background: #fff;
}
.cta-submit { align-self: end; height: 46px; }
.cta-tip {
  grid-column: 1 / -1;
  font-size: 12px;
  color: var(--c-muted);
  margin: 6px 0 0;
}

.cta-contact-row {
  margin-top: 36px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
.contact-item {
  text-align: center;
  padding: 18px;
  background: rgba(255, 255, 255, .6);
  border-radius: var(--radius-md);
}
.contact-label {
  display: block;
  font-size: 13px;
  color: var(--c-sub);
  font-weight: 600;
  margin-bottom: 6px;
}
.contact-value {
  display: block;
  font-size: 15px;
  font-weight: 700;
  color: var(--c-violet);
}

/* ---------- Footer ---------- */
.footer {
  background: #0F0A24;
  color: #B7B3D8;
  padding: 64px 0 0;
}
.footer-inner {
  display: grid;
  grid-template-columns: 1.2fr 2fr;
  gap: 48px;
  padding-bottom: 48px;
}
.footer-tag {
  margin-top: 16px;
  font-size: 14px;
  line-height: 1.7;
  max-width: 280px;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.footer-col h4 {
  font-size: 14px;
  font-weight: 700;
  color: #fff;
  margin: 0 0 16px;
  letter-spacing: 1px;
}
.footer-col a,
.footer-col span {
  display: block;
  color: #B7B3D8;
  font-size: 14px;
  padding: 4px 0;
  transition: color .2s;
}
.footer-col a:hover { color: #fff; }

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, .06);
  padding: 20px 0;
  font-size: 13px;
}
.footer-bottom .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}
.footer-bottom .container > span {
  color: #9C97C0;
  line-height: 1.8;
}

/* ICP 备案号链接（footer 深色底，需保持可读 + hover 反馈） */
.icp-link {
  color: #B7B3D8;
  text-decoration: none;
  border-bottom: 1px solid rgba(183, 179, 216, .35);
  padding-bottom: 1px;
  transition: color .2s, border-color .2s;
}
.icp-link:hover,
.icp-link:focus-visible {
  color: #fff;
  border-bottom-color: rgba(255, 255, 255, .7);
  outline: none;
}

/* ---------- 滚动出现动画 ---------- */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .6s ease, transform .6s ease;
}
.fade-in.in {
  opacity: 1;
  transform: none;
}

/* ---------- 企业微信获客二维码弹窗 ---------- */
.qr-modal {
  position: fixed;
  inset: 0;
  z-index: 1200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.qr-modal[hidden] { display: none; }

.qr-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(17, 24, 39, .55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  opacity: 0;
  transition: opacity .26s ease;
}
.qr-modal.is-open .qr-backdrop { opacity: 1; }

.qr-dialog {
  position: relative;
  width: 100%;
  max-width: 380px;
  max-height: calc(100vh - 40px);
  overflow-y: auto;
  background: #fff;
  border-radius: 24px;
  padding: 30px 26px 24px;
  text-align: center;
  box-shadow: 0 30px 70px rgba(15, 23, 42, .28);
  opacity: 0;
  transform: translateY(18px) scale(.96);
  transition: opacity .28s ease, transform .28s cubic-bezier(.34, 1.4, .64, 1);
}
.qr-modal.is-open .qr-dialog {
  opacity: 1;
  transform: translateY(0) scale(1);
}

.qr-close {
  position: absolute;
  top: 14px;
  right: 14px;
  width: 34px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  color: #6B7280;
  background: #F3F4F6;
  transition: background .2s, color .2s, transform .2s;
}
.qr-close:hover {
  background: #E5E7EB;
  color: #1F2937;
  transform: rotate(90deg);
}

.qr-head { margin-bottom: 18px; }
.qr-emoji {
  font-size: 34px;
  line-height: 1;
  margin-bottom: 10px;
}
.qr-title {
  margin: 0 0 6px;
  font-size: 21px;
  font-weight: 800;
  letter-spacing: -.2px;
  color: #1F2937;
}
.qr-sub {
  margin: 0;
  font-size: 14px;
  color: #6B7280;
}

.qr-figure {
  position: relative;
  width: 260px;
  max-width: 100%;
  margin: 0 auto 16px;
  padding: 12px;
  background: #fff;
  border: 1.5px solid #E5E7EB;
  border-radius: 18px;
  box-shadow: 0 8px 24px rgba(139, 92, 246, .12);
}
.qr-figure img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 10px;
}
.qr-scan-hint {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px dashed #E5E7EB;
  font-size: 13px;
  font-weight: 600;
  color: #8B5CF6;
}

.qr-points {
  list-style: none;
  margin: 0 0 14px;
  padding: 0;
  text-align: left;
  display: grid;
  gap: 8px;
}
.qr-points li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  font-size: 14px;
  color: #374151;
  line-height: 1.5;
}
.qr-points li span { flex: none; font-size: 13px; }

.qr-foot {
  margin: 0;
  font-size: 12px;
  color: #9CA3AF;
  line-height: 1.5;
}

.cta-qr-card {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: 14px;
  width: 100%;
  margin-top: 2px;
  padding: 12px 18px;
  background: #FAF8FF;
  border: 1.5px dashed #C4B5FD;
  border-radius: var(--radius-lg);
  text-align: left;
  transition: border-color .2s, background .2s, transform .2s, box-shadow .2s;
}
.cta-qr-card:hover {
  background: #F3EFFF;
  border-color: #8B5CF6;
  border-style: solid;
  transform: translateY(-2px);
  box-shadow: 0 10px 24px rgba(139, 92, 246, .16);
}
.qr-card-icon {
  flex: none;
  width: 52px;
  height: 52px;
  padding: 4px;
  background: #fff;
  border-radius: 12px;
  box-shadow: 0 2px 8px rgba(31, 41, 55, .08);
}
.qr-card-icon img {
  width: 100%;
  height: 100%;
  display: block;
  border-radius: 8px;
}
.qr-card-text {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
}
.qr-card-text strong {
  font-size: 15px;
  font-weight: 700;
  color: #1F2937;
  letter-spacing: -.2px;
}
.qr-card-text small {
  font-size: 13px;
  color: var(--c-muted);
}
.qr-card-arrow {
  flex: none;
  color: #8B5CF6;
  transition: transform .2s;
}
.cta-qr-card:hover .qr-card-arrow {
  transform: translateX(4px);
}

/* 移动端：弹窗贴底更顺手 */
@media (max-width: 480px) {
  .qr-modal { padding: 0; align-items: flex-end; }
  .qr-dialog {
    max-width: 100%;
    border-radius: 24px 24px 0 0;
    padding: 26px 20px 30px;
    transform: translateY(40px);
  }
  .qr-modal.is-open .qr-dialog { transform: translateY(0); }
}

/* ---------- 响应式 ---------- */
@media (max-width: 1024px) {
  .hero-inner { grid-template-columns: 1fr; gap: 40px; }
  .hero-visual { height: 380px; max-width: 480px; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .stages-grid { grid-template-columns: 1fr; }
  .process-grid { grid-template-columns: 1fr; gap: 8px; }
  .process-line { display: none; }
  .why-grid { flex-direction: column; align-items: stretch; }
  .why-item { flex: 1 1 auto; }

  /* 中等屏幕：why-grid 卡片 2 列 */
  .why-item { flex: 0 0 calc((100% - 24px) / 2); }
  .testimonials-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 28px; }
  .footer-inner { grid-template-columns: 1fr; }
}

@media (max-width: 768px) {
  .section { padding: 72px 0; }
  .section-title { font-size: 30px; }
  .hero { padding: 48px 0 80px; }
  .hero-title { font-size: 40px; }
  .hero-subtitle { font-size: 16px; }
  .hero-visual { height: 320px; max-width: 360px; margin: 0 auto; }
  .card-main { width: 260px; padding: 16px; inset: 24px 0 auto 8px; }
  .flash-en { font-size: 28px; }
  .flashcard { height: 140px; }
  .card-mini-1 { right: 0; }
  .card-mini-2 { left: -8px; }

  .nav-menu {
    display: none;
    position: absolute;
    top: 72px; left: 0; right: 0;
    flex-direction: column;
    background: #fff;
    padding: 16px 24px 24px;
    border-bottom: 1px solid var(--c-line);
    box-shadow: 0 8px 16px rgba(0,0,0,.05);
    margin: 0;
    gap: 0;
  }
  .nav-menu.open { display: flex; }
  .nav-menu a { padding: 12px 0; border-bottom: 1px solid var(--c-line); }
  .nav-menu a:last-child { border-bottom: none; }
  .nav-toggle { display: flex; }
  .nav-cta { display: none; }

  .cta-form { grid-template-columns: 1fr; }
  .cta-submit { width: 100%; }
  .cta-contact-row { grid-template-columns: 1fr; }

  .features-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .section-head { margin-bottom: 36px; }
  .stat-num { font-size: 32px; }
}

@media (max-width: 480px) {
  .hero-title { font-size: 32px; }
  .hero-buttons .btn-lg { padding: 14px 22px; font-size: 15px; }
  .section-title { font-size: 26px; }
  .cta-title { font-size: 28px; }

  /* why-grid 移动端：1 列 */
  .why-item { flex: 1 1 100%; }
}