/* ============================================================
   好好听·准音社 · 设计系统
   编辑部极简 · 暖纸底 / 深墨字 / 铜橙点缀
   ============================================================ */

:root {
  /* 颜色 */
  --paper: #0e1113;
  --paper-2: #131719;
  --paper-3: #1a1f22;
  --ink: #eae7df;
  --ink-2: #a7a39a;
  --ink-3: #7d7970;
  --line: #262b2e;
  --line-soft: #1e2326;
  --accent: #d9a05b;
  --accent-deep: #b77e3c;
  --accent-soft: rgba(217,160,91,0.14);
  --dark: #0e1113;
  --dark-2: #131719;
  --cream: #eae7df;

  /* 字体 */
  --serif: "Songti SC", "Noto Serif SC", "Source Han Serif SC", STSong, SimSun, Georgia, serif;
  --sans: "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "SF Mono", ui-monospace, "JetBrains Mono", "Roboto Mono", Menlo, monospace;

  /* 间距（8px 栅格） */
  --sp-1: 4px;
  --sp-2: 8px;
  --sp-3: 12px;
  --sp-4: 16px;
  --sp-5: 24px;
  --sp-6: 32px;
  --sp-7: 40px;
  --sp-8: 48px;
  --sp-9: 56px;
  --sp-10: 64px;
  --sp-11: 72px;
  --sp-12: 96px;

  /* 布局 */
  --container: 1160px;
  --gutter: clamp(20px, 5vw, 48px);

  /* 圆角与阴影 */
  --radius-sm: 10px;
  --radius: 18px;
  --radius-lg: 28px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.5), 0 6px 18px -10px rgba(0, 0, 0, 0.6);
  --shadow: 0 24px 60px -32px rgba(0, 0, 0, 0.75);
  --shadow-lg: 0 40px 90px -40px rgba(0, 0, 0, 0.85);

  /* 玻璃拟态 */
  --glass: rgba(255, 255, 255, 0.06);
  --glass-strong: rgba(255, 255, 255, 0.1);
  --glass-border: rgba(255, 255, 255, 0.16);
  --glass-blur: blur(26px) saturate(1.35);
  --glass-shadow: 0 18px 50px -28px rgba(0, 0, 0, 0.75), inset 0 1px 0 rgba(255, 255, 255, 0.12), inset 0 -1px 0 rgba(255, 255, 255, 0.04);

  /* 动效 */
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur: 0.55s;
}

/* ---------- 基础 ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    radial-gradient(50% 38% at 13% 4%, rgba(217, 160, 91, 0.2), transparent 72%),
    radial-gradient(42% 34% at 88% 16%, rgba(217, 160, 91, 0.15), transparent 72%),
    radial-gradient(40% 34% at 78% 86%, rgba(217, 160, 91, 0.17), transparent 72%),
    radial-gradient(34% 30% at 8% 70%, rgba(217, 160, 91, 0.11), transparent 72%);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

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

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

button {
  font-family: inherit;
  cursor: pointer;
  border: 0;
  background: none;
  color: inherit;
}

::selection {
  background: var(--accent);
  color: #1a1408;
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 200;
  padding: 10px 16px;
  background: var(--dark);
  color: var(--cream);
  border-radius: 8px;
  transition: top 0.2s;
}

.skip-link:focus {
  top: 12px;
}

section[id],
[id] {
  scroll-margin-top: 96px;
}

/* 滚动进度条 */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 150;
  height: 2px;
  width: 0;
  background: var(--accent);
  transition: width 0.1s linear;
}

/* ---------- 布局 ---------- */
.container {
  width: min(100% - var(--gutter) * 2, var(--container));
  margin-inline: auto;
}

.section {
  padding: var(--sp-11) 0;
}

.section--tint {
  background:
    radial-gradient(40% 60% at 90% 10%, rgba(217, 160, 91, 0.1), transparent 70%),
    radial-gradient(36% 55% at 6% 90%, rgba(217, 160, 91, 0.1), transparent 70%),
    var(--paper-2);
  border-block: 1px solid var(--line-soft);
}

/* ---------- 排版 ---------- */
.eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--sp-4);
}

.eyebrow--light {
  color: var(--accent-soft);
}

.section-head {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  align-items: end;
  gap: var(--sp-8);
  margin-bottom: var(--sp-6);
}

.section-head h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(32px, 4.4vw, 48px);
  line-height: 1.16;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.section-head__aside {
  max-width: 420px;
  justify-self: end;
}

.section-head__aside p {
  font-size: 16px;
  color: var(--ink-2);
  padding-left: var(--sp-5);
  border-left: 1px solid var(--line);
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  font-size: 15px;
  font-weight: 600;
  letter-spacing: 0.01em;
  line-height: 1;
  padding: 16px 28px;
  border-radius: 999px;
  transition: transform 0.25s var(--ease-out), box-shadow 0.25s var(--ease-out), background 0.25s, color 0.25s, border-color 0.25s;
  white-space: nowrap;
}

.btn:active {
  transform: scale(0.97);
}

.btn svg {
  width: 16px;
  height: 16px;
  flex: none;
}

.btn--primary {
  background: var(--cream);
  color: var(--dark);
}

.btn--primary:hover {
  background: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 16px 32px -16px rgba(217, 160, 91, 0.55);
}

.btn--accent {
  background: var(--accent);
  color: #1a1408;
  box-shadow: 0 10px 24px -12px rgba(217, 160, 91, 0.45);
}

.btn--accent:hover {
  background: var(--accent-deep);
  transform: translateY(-2px);
  box-shadow: 0 18px 36px -14px rgba(217, 160, 91, 0.5);
}

.btn--ghost {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--line);
}

.btn--ghost:hover {
  border-color: var(--ink);
  transform: translateY(-2px);
}

.btn--cream {
  background: var(--cream);
  color: var(--dark);
}

.btn--cream:hover {
  background: #fff;
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.btn--outline {
  background: transparent;
  color: var(--cream);
  border: 1px solid rgba(240, 235, 224, 0.4);
}

.btn--outline:hover {
  border-color: #fff;
  color: #fff;
  transform: translateY(-2px);
}

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

.btn--sm {
  padding: 12px 20px;
  font-size: 14px;
}

/* ---------- 顶部导航 ---------- */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(13, 11, 8, 0.72);
  -webkit-backdrop-filter: saturate(1.6) blur(16px);
  backdrop-filter: saturate(1.6) blur(16px);
  border-bottom: 1px solid transparent;
  transition: background 0.35s, border-color 0.35s;
}

.site-header.is-scrolled {
  border-bottom-color: var(--line-soft);
  background: rgba(13, 11, 8, 0.88);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-5);
  height: 76px;
}

.brand,
.logo {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  flex: none;
}

.brand__mark,
.logo__mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 11px;
  overflow: hidden;
  background: var(--paper-3);
}

.brand__mark img,
.logo__mark img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.brand__text,
.logo__text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand__cn,
.logo__cn {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 17px;
  letter-spacing: 0.02em;
}

.brand__en,
.logo__en {
  font-family: var(--mono);
  font-size: 9.5px;
  letter-spacing: 0.28em;
  color: var(--ink-3);
  text-transform: uppercase;
}

.nav {
  display: flex;
  align-items: center;
  gap: var(--sp-6);
}

.nav a {
  position: relative;
  font-size: 15px;
  color: var(--ink-2);
  transition: color 0.2s;
}

.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 100%;
  height: 1.5px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.3s var(--ease-out);
}

.nav a:hover {
  color: var(--ink);
}

.nav a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}

.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 44px;
  height: 44px;
  padding: 10px;
  border-radius: 12px;
  background: transparent;
}

.menu-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--ink);
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.2s;
}

.menu-toggle span:first-child {
  width: 22px;
}

.menu-toggle span:last-child {
  width: 15px;
  align-self: flex-end;
}

.mobile-nav {
  display: none;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  padding: calc(76px + var(--sp-8)) 0 var(--sp-9);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(58% 46% at 78% 8%, rgba(217, 160, 91, 0.16), transparent 70%),
    radial-gradient(46% 40% at 10% 88%, rgba(217, 160, 91, 0.1), transparent 70%);
  pointer-events: none;
}

.hero__inner {
  position: relative;
  will-change: transform;
}

.hero__title {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(46px, 8.5vw, 92px);
  line-height: 1.04;
  letter-spacing: -0.02em;
  margin: var(--sp-4) 0 var(--sp-5);
}

.hero__title.is-split .char {
  display: inline-block;
  opacity: 0;
  transform: translateY(0.5em);
  transition: opacity 0.55s var(--ease-out), transform 0.55s var(--ease-out);
  will-change: opacity, transform;
}

.hero__title.is-split .char.is-in {
  opacity: 1;
  transform: none;
}

.hero__title em {
  font-style: normal;
  color: var(--accent);
  text-shadow: 0 0 26px rgba(217, 160, 91, 0.28);
}

.hero__sub {
  max-width: 560px;
  font-size: clamp(17px, 2vw, 19px);
  line-height: 1.75;
  color: var(--ink-2);
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-3);
  margin-top: var(--sp-7);
}

.marquee {
  margin-top: var(--sp-7);
  padding: 18px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  -webkit-mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent);
  mask-image: linear-gradient(90deg, transparent, #000 10%, #000 90%, transparent);
}

.marquee__track {
  display: flex;
  width: max-content;
  animation: marquee-scroll 30s linear infinite;
}

.marquee__group {
  display: flex;
  align-items: center;
  gap: var(--sp-7);
  padding-right: var(--sp-7);
  flex: none;
}

.marquee__group span {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 15px;
  color: var(--ink-2);
  white-space: nowrap;
}

.marquee__group em {
  font-style: normal;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--accent);
}

@keyframes marquee-scroll {
  from {
    transform: translateX(0);
  }
  to {
    transform: translateX(-50%);
  }
}

.hero-stats {
  display: flex;
  gap: var(--sp-8);
  margin-top: var(--sp-7);
}

.is-tiltable {
  transform-style: preserve-3d;
  will-change: transform;
  transition: transform 0.2s ease-out;
}

.hero-stat {
  display: flex;
  flex-direction: column;
}

.hero-stat__num {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(30px, 4vw, 40px);
  line-height: 1;
  letter-spacing: -0.02em;
}

.hero-stat__num .suffix {
  color: var(--accent);
}

.hero-stat__label {
  font-size: 13px;
  color: var(--ink-3);
  margin-top: var(--sp-2);
}

/* ---------- 关于我们 ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: var(--sp-8);
  align-items: start;
  margin-bottom: var(--sp-7);
}

.about-intro h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(30px, 4.4vw, 44px);
  line-height: 1.18;
}

.about-body {
  display: grid;
  gap: var(--sp-4);
}

.about-body p {
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-2);
}

.about-body .about-lead {
  font-family: var(--serif);
  font-size: 19px;
  line-height: 1.7;
  color: var(--ink);
}

.about-promises {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-5);
}

.about-promise {
  padding: var(--sp-6);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
}

.about-promise__num {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--accent);
  padding-bottom: var(--sp-2);
  border-bottom: 1px solid rgba(217, 160, 91, 0.25);
  margin-bottom: var(--sp-4);
}

.about-promise h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 21px;
  margin-bottom: var(--sp-2);
}

.about-promise p {
  font-size: 14px;
  color: var(--ink-2);
}

/* ---------- 课程体系 ---------- */
.journey-list {
  position: relative;
  display: grid;
  gap: var(--sp-7);
}

.journey-list::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 8px;
  bottom: 8px;
  width: 1px;
  background: linear-gradient(180deg, var(--accent), var(--line) 85%);
  opacity: 0.55;
}

.journey-step {
  position: relative;
  display: grid;
  grid-template-columns: 32px 1fr;
  align-items: start;
  gap: var(--sp-5);
}

.journey-step__num {
  position: relative;
  z-index: 1;
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--paper);
  border: 1px solid var(--accent);
  color: var(--accent);
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.06em;
}

.journey-step--soon .journey-step__num {
  border-color: var(--line);
  color: var(--ink-3);
}

.journey-step__head {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: baseline;
  gap: var(--sp-4);
  margin-bottom: var(--sp-3);
}

.journey-step__head h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 24px;
}

.journey-step__content > p {
  font-size: 15px;
  color: var(--ink-2);
  max-width: 680px;
}

.journey-step__tag {
  font-size: 13px;
  padding: 6px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  color: var(--ink-2);
  white-space: nowrap;
}

.journey-step__tag--link {
  color: var(--accent);
  border-color: var(--accent);
  transition: background 0.2s, color 0.2s;
}

.journey-step__tag--link:hover {
  background: var(--accent);
  color: #1a1408;
}

.journey-step--soon {
  opacity: 0.62;
}

/* ---------- 理念 ---------- */
.principle-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-6);
}

.principle {
  padding: var(--sp-6);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  transition: transform 0.35s var(--ease-out), box-shadow 0.35s var(--ease-out), border-color 0.35s;
}

.principle:hover {
  transform: translateY(-6px);
  border-color: var(--line);
  box-shadow: var(--shadow);
}

.principle__num {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--accent);
  padding-bottom: var(--sp-2);
  border-bottom: 1px solid var(--line);
  margin-bottom: var(--sp-5);
}

.principle h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 24px;
  margin-bottom: var(--sp-3);
}

.principle p {
  font-size: 15px;
  color: var(--ink-2);
}

/* ---------- 定价 ---------- */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--sp-6);
  align-items: stretch;
}

.pricing-card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: var(--sp-7);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: transform 0.35s var(--ease-out), box-shadow 0.35s var(--ease-out), border-color 0.35s;
}

.pricing-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.pricing-card--hot {
  border-color: var(--accent);
  box-shadow: var(--shadow);
}

.pricing-card__tag {
  position: absolute;
  top: 22px;
  right: 22px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: #1a1408;
  background: var(--accent);
  padding: 6px 14px;
  border-radius: 999px;
}

.pricing-card__head {
  margin-bottom: var(--sp-6);
}

.pricing-card__kicker {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.24em;
  color: var(--ink-3);
}

.pricing-card--hot .pricing-card__kicker {
  color: var(--accent);
}

.pricing-card__head h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 28px;
  margin: var(--sp-3) 0 var(--sp-2);
}

.pricing-card__head p {
  font-size: 15px;
  color: var(--ink-2);
}

.pricing-card__price {
  display: flex;
  align-items: baseline;
  gap: var(--sp-2);
  padding-bottom: var(--sp-5);
  border-bottom: 1px solid var(--line-soft);
  margin-bottom: var(--sp-5);
}

.pricing-card__price strong {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 48px;
  letter-spacing: -0.02em;
}

.pricing-card__price span {
  font-size: 14px;
  color: var(--ink-3);
}

.pricing-card__list {
  list-style: none;
  display: grid;
  gap: var(--sp-3);
  margin-bottom: var(--sp-6);
  flex: 1;
}

.pricing-card__list li {
  position: relative;
  padding-left: 26px;
  font-size: 15px;
  color: var(--ink-2);
}

.pricing-card__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 7px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent-soft);
  border: 1px solid var(--accent);
}

.pricing-card__list li::after {
  content: "";
  position: absolute;
  left: 5px;
  top: 9.5px;
  width: 6px;
  height: 3.5px;
  border-left: 1.5px solid var(--accent);
  border-bottom: 1.5px solid var(--accent);
  transform: rotate(-45deg);
}

.upgrade-note,
.coming-line {
  text-align: center;
  font-size: 14px;
  color: var(--ink-3);
  margin-top: var(--sp-6);
}

.upgrade-note + .coming-line {
  margin-top: var(--sp-3);
}

.coming-line a {
  color: var(--accent);
  border-bottom: 1px solid var(--accent-soft);
}

/* ---------- 测一测 ---------- */
.quiz-card {
  max-width: 720px;
  margin-inline: auto;
  padding: var(--sp-8);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.quiz-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--sp-5);
}

.quiz-step {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--ink-3);
}

.quiz-dots {
  display: flex;
  gap: 6px;
}

.quiz-dots span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--line);
  transition: background 0.3s, transform 0.3s;
}

.quiz-dots span.is-on {
  background: var(--accent);
  transform: scale(1.25);
}

.quiz-q {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(22px, 3vw, 28px);
  line-height: 1.3;
  margin-bottom: var(--sp-6);
}

.quiz-options {
  display: grid;
  gap: var(--sp-3);
}

.quiz-option {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  width: 100%;
  text-align: left;
  padding: 18px 20px;
  font-size: 16px;
  color: var(--ink);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  transition: border-color 0.25s, background 0.25s, transform 0.25s var(--ease-out);
}

.quiz-option:hover {
  border-color: var(--accent);
  background: var(--accent-soft);
  transform: translateX(4px);
}

.quiz-option.is-selected {
  border-color: var(--accent);
  background: var(--accent-soft);
  transform: translateX(4px);
  pointer-events: none;
}

.quiz-option svg {
  width: 18px;
  height: 18px;
  flex: none;
  color: var(--ink-3);
  transition: transform 0.25s, color 0.25s;
}

.quiz-option:hover svg {
  color: var(--accent);
  transform: translateX(3px);
}

.quiz-result {
  text-align: center;
}

.quiz-result__label {
  display: inline-block;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  color: #1a1408;
  background: var(--accent);
  padding: 8px 18px;
  border-radius: 999px;
  margin-bottom: var(--sp-5);
}

.quiz-result h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 28px;
  margin-bottom: var(--sp-3);
}

.quiz-result > p {
  color: var(--ink-2);
  margin-bottom: var(--sp-6);
}

.quiz-result__actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--sp-3);
}

.quiz-retry {
  display: block;
  margin: var(--sp-5) auto 0;
  font-size: 14px;
  color: var(--ink-3);
  border-bottom: 1px solid var(--line);
  transition: color 0.2s;
}

.quiz-retry:hover {
  color: var(--ink);
}

.quiz-q,
.quiz-options {
  animation: quiz-fade 0.3s ease-out;
}

@keyframes quiz-fade {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

/* ---------- 服务 ---------- */
.service-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--sp-6);
}

.service-card {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: var(--sp-7);
  padding: var(--sp-7);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  transition: transform 0.35s var(--ease-out), box-shadow 0.35s;
}

.service-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow);
}

.service-card--wide {
  grid-column: 1 / -1;
  grid-template-columns: 1.6fr 1fr;
}

.service-card__main {
  display: flex;
  flex-direction: column;
}

.service-card__top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  text-transform: uppercase;
  margin-bottom: var(--sp-5);
}

.service-card__mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  font-family: var(--serif);
  font-size: 18px;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 12px;
}

.service-card h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 26px;
  margin-bottom: var(--sp-2);
}

.service-card__sub {
  font-size: 15px;
  color: var(--accent);
  margin-bottom: var(--sp-4);
}

.service-card__desc {
  font-size: 15px;
  color: var(--ink-2);
  margin-bottom: var(--sp-4);
}

.service-tracks {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  list-style: none;
}

.service-tracks li {
  font-size: 13px;
  color: var(--ink-2);
  padding: 6px 14px;
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: 999px;
}

.service-card__side {
  display: flex;
  flex-direction: column;
  border-left: 1px solid var(--line-soft);
  padding-left: var(--sp-6);
}

.service-prices {
  display: grid;
  gap: var(--sp-3);
}

.service-price {
  display: flex;
  align-items: baseline;
  gap: var(--sp-3);
}

.service-price span {
  font-size: 13px;
  color: var(--ink-3);
}

.service-price strong {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 20px;
}

.service-price em {
  font-style: normal;
  font-size: 12px;
  color: var(--ink-3);
}

.service-card__note {
  font-size: 13px;
  color: var(--ink-3);
  margin: var(--sp-5) 0;
}

.service-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
  margin-top: auto;
}

.service-actions .btn {
  padding: 12px 18px;
  font-size: 14px;
}

.service-footnote {
  font-size: 13px;
  color: var(--ink-3);
  text-align: center;
  margin-top: var(--sp-6);
}

/* ---------- 讲师 ---------- */
.teacher-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: var(--sp-8);
  align-items: center;
  margin-bottom: var(--sp-8);
}

.teacher-portrait__frame {
  position: relative;
  aspect-ratio: 4 / 5;
  background: linear-gradient(160deg, #1a1f22, #0e1113);
  border-radius: var(--radius-lg);
  padding: var(--sp-6);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  color: var(--cream);
  overflow: hidden;
}

.teacher-portrait__frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(60% 50% at 50% 0%, rgba(217, 160, 91, 0.35), transparent 70%);
}

.teacher-portrait__frame--image {
  padding: 0;
}

.teacher-portrait__image {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.teacher-portrait__top,
.teacher-portrait__bottom {
  position: relative;
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(240, 235, 224, 0.6);
}

.teacher-portrait__glyph {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: var(--serif);
  font-size: 160px;
  color: rgba(240, 235, 224, 0.08);
}

.teacher-portrait__stamp {
  position: absolute;
  right: 26px;
  bottom: 26px;
  font-family: var(--serif);
  font-size: 15px;
  color: rgba(240, 235, 224, 0.55);
  transform: rotate(-8deg);
  border: 1px solid rgba(240, 235, 224, 0.35);
  padding: 8px 14px;
  border-radius: 6px;
}

.teacher-copy h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(28px, 3.6vw, 40px);
  line-height: 1.2;
  margin-bottom: var(--sp-4);
}

.teacher-copy > p:not(.eyebrow) {
  color: var(--ink-2);
  margin-bottom: var(--sp-5);
}

.teacher-proofs {
  display: grid;
  gap: var(--sp-2);
  list-style: none;
  margin-bottom: var(--sp-5);
}

.teacher-proofs li {
  position: relative;
  padding-left: 22px;
  font-size: 15px;
  color: var(--ink-2);
}

.teacher-proofs li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
}

.teacher-quote {
  font-family: var(--serif);
  font-size: 20px;
  color: var(--accent-deep);
  padding-left: var(--sp-5);
  border-left: 2px solid var(--accent);
  margin-bottom: var(--sp-5);
}

.teacher-sign {
  display: flex;
  align-items: center;
  gap: var(--sp-4);
}

.teacher-sign__name {
  font-family: var(--serif);
  font-size: 28px;
  color: var(--accent);
}

.teacher-sign__meta {
  font-size: 13px;
  color: var(--ink-3);
}

.teacher-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-5);
}

.teacher-person {
  padding: var(--sp-6);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
}

.teacher-person__head {
  display: flex;
  align-items: baseline;
  gap: var(--sp-3);
  padding-bottom: var(--sp-4);
  border-bottom: 1px solid var(--line-soft);
  margin-bottom: var(--sp-4);
}

.teacher-person__head h4 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 22px;
}

.teacher-person__role {
  font-size: 13px;
  color: var(--accent);
}

.teacher-person__training {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  color: var(--ink-3);
  margin-bottom: var(--sp-4);
}

.teacher-person__bio {
  font-size: 15px;
  color: var(--ink-2);
  margin-bottom: var(--sp-4);
}

.teacher-person__awards {
  display: grid;
  gap: var(--sp-2);
  list-style: none;
}

.teacher-person__awards li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--ink-2);
}

.teacher-person__awards li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--accent);
}

/* ---------- 学员反馈 ---------- */
.feedback-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-5);
}

.feedback-card {
  display: flex;
  flex-direction: column;
  gap: var(--sp-5);
  padding: var(--sp-6);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}

.feedback-card blockquote {
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-2);
  flex: 1;
}

.feedback-card figcaption {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding-top: var(--sp-4);
  border-top: 1px solid var(--line-soft);
}

.feedback-card__name {
  font-weight: 600;
  font-size: 14px;
}

.feedback-card__course {
  font-size: 12px;
  color: var(--accent);
  margin-left: auto;
}

.teacher-person--soon {
  opacity: 0.6;
  border-style: dashed;
}

/* ---------- FAQ ---------- */
.faq-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: var(--sp-8);
  align-items: start;
}

.faq-intro {
  position: sticky;
  top: 110px;
}

.faq-intro h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(30px, 3.8vw, 42px);
  line-height: 1.18;
  margin-bottom: var(--sp-4);
}

.faq-intro > p:not(.eyebrow) {
  color: var(--ink-2);
  margin-bottom: var(--sp-5);
}

.faq-list {
  display: grid;
  gap: var(--sp-3);
}

.faq-item {
  background: var(--paper);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.3s;
}

.faq-item:has(.faq-toggle[aria-expanded="true"]) {
  border-color: var(--line);
}

.faq-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  width: 100%;
  text-align: left;
  padding: 20px 24px;
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
}

.faq-icon {
  position: relative;
  width: 20px;
  height: 20px;
  flex: none;
}

.faq-icon::before,
.faq-icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  background: var(--accent);
  transition: transform 0.3s var(--ease);
}

.faq-icon::before {
  width: 14px;
  height: 1.6px;
  transform: translate(-50%, -50%);
}

.faq-icon::after {
  width: 1.6px;
  height: 14px;
  transform: translate(-50%, -50%);
}

.faq-toggle[aria-expanded="true"] .faq-icon::after {
  transform: translate(-50%, -50%) scaleY(0);
}

.faq-panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.4s var(--ease);
}

.faq-panel.is-open {
  grid-template-rows: 1fr;
}

.faq-panel > div {
  overflow: hidden;
}

.faq-panel p {
  padding: 0 24px 22px;
  font-size: 15px;
  color: var(--ink-2);
}

/* ---------- CTA ---------- */
.cta-section {
  padding: 0 0 var(--sp-11);
}

.cta-panel {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-8);
  padding: var(--sp-9);
  background: linear-gradient(150deg, #201710, #0e1113);
  border-radius: var(--radius-lg);
  overflow: hidden;
  position: relative;
}

.cta-panel::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(50% 80% at 88% 10%, rgba(217, 160, 91, 0.4), transparent 65%);
}

.cta-copy {
  position: relative;
  max-width: 560px;
}

.cta-copy h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(28px, 3.8vw, 42px);
  line-height: 1.18;
  color: var(--cream);
  margin-bottom: var(--sp-4);
}

.cta-copy > p:not(.eyebrow) {
  color: rgba(240, 235, 224, 0.7);
}

.cta-actions {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  flex: none;
}

/* ---------- PWA 安装引导（仅手机端显示） ---------- */
.pwa-guide {
  display: none;
  padding: var(--sp-6) 0 var(--sp-9);
}

.pwa-guide__inner {
  padding: 0;
  background: rgba(255, 255, 255, 0.03);
  border: 1px dashed var(--glass-border);
  border-radius: var(--radius);
}

.pwa-guide__toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-3);
  width: 100%;
  padding: var(--sp-4) var(--sp-5);
  text-align: left;
}

.pwa-guide__title {
  font-size: 15px;
  font-weight: 600;
}

.pwa-guide__icon {
  position: relative;
  width: 18px;
  height: 18px;
  flex: none;
}

.pwa-guide__icon::before,
.pwa-guide__icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  background: var(--accent);
  border-radius: 1px;
  transition: transform 0.3s var(--ease);
}

.pwa-guide__icon::before {
  width: 14px;
  height: 1.6px;
  transform: translate(-50%, -50%);
}

.pwa-guide__icon::after {
  width: 1.6px;
  height: 14px;
  transform: translate(-50%, -50%);
}

.pwa-guide__toggle[aria-expanded="true"] .pwa-guide__icon::after {
  transform: translate(-50%, -50%) scaleY(0);
}

.pwa-guide__panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.35s var(--ease);
}

.pwa-guide__panel.is-open {
  grid-template-rows: 1fr;
}

.pwa-guide__panel-inner {
  overflow: hidden;
  padding: 0 var(--sp-5) var(--sp-5);
}

.pwa-guide__sub {
  font-size: 13px;
  color: var(--ink-3);
  margin-bottom: var(--sp-4);
}

.pwa-guide__grid {
  display: grid;
  gap: var(--sp-3);
}

.pwa-step {
  padding: var(--sp-4);
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
}

.pwa-step h3 {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: var(--sp-2);
}

.pwa-step ol {
  list-style: none;
  counter-reset: pwa-step;
  display: grid;
  gap: 6px;
}

.pwa-step li {
  position: relative;
  padding-left: 26px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--ink-2);
  counter-increment: pwa-step;
}

.pwa-step li::before {
  content: counter(pwa-step);
  position: absolute;
  left: 0;
  top: 2px;
  display: grid;
  place-items: center;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  font-family: var(--mono);
  font-size: 11px;
}

/* ---------- Footer ---------- */
.site-footer {
  padding: var(--sp-10) 0 var(--sp-7);
  background: #0a0c0e;
  color: rgba(240, 235, 224, 0.75);
}

.footer-main {
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1.2fr;
  gap: var(--sp-8);
  padding-bottom: var(--sp-8);
  border-bottom: 1px solid rgba(240, 235, 224, 0.12);
}

.footer-brand .brand__cn,
.footer-brand .logo__cn {
  color: var(--cream);
}

.footer-brand .brand__mark,
.footer-brand .logo__mark {
  background: rgba(240, 235, 224, 0.12);
}

.footer-brand > p {
  margin-top: var(--sp-4);
  font-size: 14px;
  color: rgba(240, 235, 224, 0.55);
}

.footer-col h4 {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent-soft);
  margin-bottom: var(--sp-4);
}

.footer-col ul {
  list-style: none;
  display: grid;
  gap: var(--sp-3);
}

.footer-col a,
.footer-contact button {
  font-size: 14px;
  color: rgba(240, 235, 224, 0.75);
  transition: color 0.2s;
}

.footer-col a:hover,
.footer-contact button:hover {
  color: #fff;
}

.footer-contact button {
  text-align: left;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  padding-top: var(--sp-6);
  font-size: 13px;
  color: rgba(240, 235, 224, 0.45);
}

.footer-bottom__links {
  display: flex;
  gap: var(--sp-5);
}

.footer-bottom__links a {
  color: rgba(240, 235, 224, 0.45);
}

.footer-bottom__links a:hover {
  color: #fff;
}

/* ---------- Toast ---------- */
.toast {
  position: fixed;
  left: 50%;
  bottom: 32px;
  transform: translate(-50%, 24px);
  z-index: 300;
  padding: 14px 24px;
  background: var(--dark);
  color: var(--cream);
  font-size: 14px;
  border-radius: 999px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s, transform 0.3s var(--ease-out);
}

.toast.is-visible {
  opacity: 1;
  transform: translate(-50%, 0);
}

/* ============================================================
   课程详情页
   ============================================================ */
.course-page {
  padding: calc(76px + var(--sp-8)) 0 var(--sp-10);
}

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--sp-2);
  font-size: 13px;
  color: var(--ink-3);
  margin-bottom: var(--sp-7);
}

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

.course-fallback {
  padding: var(--sp-10) 0;
  text-align: center;
}

.course-fallback h1 {
  font-family: var(--serif);
  font-size: 32px;
  margin-bottom: var(--sp-4);
}

.course-fallback p {
  color: var(--ink-2);
}

.course-fallback a {
  color: var(--accent);
}

.course-hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: var(--sp-8);
  align-items: center;
  margin-bottom: var(--sp-9);
}

.course-label {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--accent);
  margin-bottom: var(--sp-4);
}

.course-label__dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
}

.course-title {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(36px, 5.5vw, 56px);
  line-height: 1.1;
  letter-spacing: -0.015em;
  margin-bottom: var(--sp-4);
}

.course-subtitle {
  font-size: 18px;
  color: var(--accent);
  margin-bottom: var(--sp-4);
}

.course-summary {
  font-size: 16px;
  color: var(--ink-2);
  margin-bottom: var(--sp-6);
}

.course-meta {
  display: grid;
  grid-template-columns: repeat(3, auto);
  gap: var(--sp-6);
  justify-content: start;
  padding-top: var(--sp-5);
  border-top: 1px solid var(--line);
}

.course-meta__item {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.course-meta__item span {
  font-size: 12px;
  color: var(--ink-3);
}

.course-meta__item strong {
  font-size: 16px;
}

.course-hero-cover {
  position: relative;
}

.course-hero-cover__tag {
  position: absolute;
  left: 20px;
  bottom: 20px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.9);
  background: rgba(0, 0, 0, 0.35);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  padding: 8px 16px;
  border-radius: 999px;
}

.course-layout {
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: var(--sp-8);
  align-items: start;
}

.course-layout--coming {
  grid-template-columns: 1fr;
}

.course-main {
  display: grid;
  gap: var(--sp-8);
}

.content-section h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 28px;
  margin-bottom: var(--sp-5);
  padding-bottom: var(--sp-4);
  border-bottom: 1px solid var(--line);
}

.prose {
  display: grid;
  gap: var(--sp-4);
  color: var(--ink-2);
}

.prose p {
  font-size: 16px;
  line-height: 1.8;
}

.outcome-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--sp-4);
}

.outcome {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-3);
  padding: var(--sp-4);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  font-size: 15px;
  color: var(--ink-2);
}

.outcome svg {
  width: 20px;
  height: 20px;
  flex: none;
  color: var(--accent);
  margin-top: 2px;
}

.audience-box {
  padding: var(--sp-5);
  background: var(--accent-soft);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  font-size: 15px;
  color: var(--ink-2);
}

.curriculum-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--sp-4);
  margin-bottom: var(--sp-5);
}

.curriculum-head h2 {
  border-bottom: none;
  padding-bottom: 0;
  margin-bottom: 0;
}

.curriculum-head > span {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.1em;
  color: var(--ink-3);
}

.curriculum {
  display: grid;
  gap: var(--sp-3);
}

.chapter {
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--paper-2);
}

.chapter-toggle {
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  width: 100%;
  text-align: left;
  padding: 18px 22px;
}

.chapter-toggle__num {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--accent);
  flex: none;
}

.chapter-toggle__title {
  display: flex;
  flex-direction: column;
  font-size: 16px;
  font-weight: 600;
}

.chapter-toggle__title small {
  font-size: 12px;
  font-weight: 400;
  color: var(--ink-3);
}

.chapter-toggle .faq-icon {
  margin-left: auto;
}

.chapter-panel {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.4s var(--ease);
}

.chapter-panel.is-open {
  grid-template-rows: 1fr;
}

.chapter-panel > div {
  overflow: hidden;
}

.lesson-list {
  list-style: none;
  padding: 0 22px 20px;
}

.lesson {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: 12px 0;
  border-top: 1px solid var(--line-soft);
  font-size: 15px;
  color: var(--ink-2);
}

.lesson__play {
  display: grid;
  place-items: center;
  width: 26px;
  height: 26px;
  flex: none;
  color: var(--accent);
  background: var(--accent-soft);
  border-radius: 50%;
}

.lesson__play svg {
  width: 11px;
  height: 11px;
}

.lesson__title {
  flex: 1;
}

.lesson__free {
  font-size: 11px;
  color: var(--accent);
  border: 1px solid var(--accent);
  padding: 2px 8px;
  border-radius: 999px;
}

.teacher-mini {
  display: flex;
  gap: var(--sp-5);
  padding: var(--sp-6);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
}

.teacher-mini__avatar {
  display: grid;
  place-items: center;
  width: 64px;
  height: 64px;
  flex: none;
  font-family: var(--serif);
  font-size: 28px;
  color: var(--cream);
  background: var(--paper-3);
  border-radius: 16px;
}

.teacher-mini__meta {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  color: var(--accent);
  margin-bottom: var(--sp-1);
}

.teacher-mini h3 {
  font-family: var(--serif);
  font-size: 22px;
  margin-bottom: var(--sp-2);
}

.teacher-mini p {
  font-size: 15px;
  color: var(--ink-2);
}

.buy-card {
  position: sticky;
  top: 104px;
  padding: var(--sp-6);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.buy-card__label {
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: var(--sp-4);
}

.buy-card__price strong {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 44px;
}

.buy-card__note {
  font-size: 13px;
  color: var(--ink-3);
  margin: var(--sp-3) 0 var(--sp-5);
}

.buy-card .btn {
  margin-bottom: var(--sp-3);
}

.buy-card__includes {
  list-style: none;
  display: grid;
  gap: var(--sp-3);
  margin: var(--sp-5) 0;
  padding-top: var(--sp-5);
  border-top: 1px solid var(--line-soft);
}

.buy-card__includes li {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-2);
  font-size: 14px;
  color: var(--ink-2);
}

.buy-card__includes svg {
  width: 16px;
  height: 16px;
  flex: none;
  color: var(--accent);
  margin-top: 3px;
}

.buy-card__secure {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-2);
  font-size: 12px;
  color: var(--ink-3);
}

.buy-card__secure svg {
  width: 16px;
  height: 16px;
  flex: none;
  margin-top: 2px;
}

.coming-title {
  font-family: var(--serif);
  font-size: 28px;
  margin-bottom: var(--sp-2);
}

.not-found {
  padding: var(--sp-10) 0;
  text-align: center;
}

.not-found__code {
  font-family: var(--serif);
  font-size: 96px;
  line-height: 1;
  color: var(--accent-soft);
  margin-bottom: var(--sp-4);
}

.not-found h1 {
  font-family: var(--serif);
  font-size: 30px;
  margin-bottom: var(--sp-3);
}

.not-found p {
  color: var(--ink-2);
  margin-bottom: var(--sp-6);
}

/* ---------- cover 卡片图案 ---------- */
.cover {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  aspect-ratio: 4 / 3;
  padding: 22px;
  border-radius: var(--radius);
  background: linear-gradient(150deg, var(--c1), var(--c2));
  color: var(--cink, #fff);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.cover--img {
  padding: 0;
}

.cover--img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.cover--large {
  aspect-ratio: 4 / 5;
  padding: 26px;
  border-radius: var(--radius-lg);
}

.cover--line::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    115deg,
    rgba(255, 255, 255, 0.05) 0 1px,
    transparent 1px 22px
  );
}

.cover--arcs::before {
  content: "";
  position: absolute;
  inset: -20%;
  background:
    radial-gradient(circle at 20% 120%, rgba(255, 255, 255, 0.18), transparent 45%),
    radial-gradient(circle at 90% -10%, rgba(255, 255, 255, 0.16), transparent 50%);
}

.cover__index {
  display: flex;
  flex-direction: column;
  gap: 2px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  opacity: 0.75;
}

.cover__glyph {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font-family: var(--serif);
  font-size: 96px;
  opacity: 0.22;
}

.cover--large .cover__glyph {
  font-size: 150px;
}

.cover__bottom {
  display: flex;
  justify-content: space-between;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  opacity: 0.75;
}

/* ---------- Modal ---------- */
.modal {
  position: fixed;
  inset: 0;
  z-index: 250;
  display: grid;
  place-items: center;
  padding: var(--sp-5);
}

.modal[hidden] {
  display: none;
}

.modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  -webkit-backdrop-filter: blur(6px);
  backdrop-filter: blur(6px);
}

.modal__card {
  position: relative;
  width: min(100%, 520px);
  max-height: calc(100vh - 48px);
  overflow: auto;
  background: var(--paper-2);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  animation: modal-in 0.35s var(--ease-out);
}

@keyframes modal-in {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

.modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 22px 26px;
  border-bottom: 1px solid var(--line-soft);
}

.modal__header h2 {
  font-family: var(--serif);
  font-size: 22px;
}

.modal__close {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  color: var(--ink-3);
  transition: background 0.2s, color 0.2s;
}

.modal__close:hover {
  background: var(--paper-3);
  color: var(--ink);
}

.modal__close svg {
  width: 18px;
  height: 18px;
}

.modal__body {
  padding: 26px;
}

.demo-note {
  display: flex;
  gap: var(--sp-3);
  padding: var(--sp-4);
  font-size: 13px;
  color: var(--ink-2);
  background: var(--accent-soft);
  border-radius: var(--radius-sm);
  margin-bottom: var(--sp-5);
}

.demo-note svg {
  width: 18px;
  height: 18px;
  flex: none;
  color: var(--accent);
}

.order-course {
  display: flex;
  gap: var(--sp-4);
  padding-bottom: var(--sp-5);
  border-bottom: 1px solid var(--line-soft);
  margin-bottom: var(--sp-5);
}

.order-course .cover {
  width: 92px;
  flex: none;
}

.order-course h3 {
  font-family: var(--serif);
  font-size: 20px;
  margin-bottom: var(--sp-2);
}

.order-course p {
  font-size: 13px;
  color: var(--ink-3);
}

.order-lines {
  display: grid;
  gap: var(--sp-3);
  margin-bottom: var(--sp-5);
}

.order-line {
  display: flex;
  justify-content: space-between;
  font-size: 14px;
  color: var(--ink-2);
}

.order-line--total {
  font-size: 16px;
  color: var(--ink);
}

.order-line--total strong {
  font-family: var(--serif);
  font-size: 24px;
  color: var(--accent-deep);
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-4);
  margin-bottom: var(--sp-5);
}

.field {
  display: grid;
  gap: 6px;
}

.field label {
  font-size: 13px;
  font-weight: 600;
}

.field input {
  width: 100%;
  padding: 13px 14px;
  font-size: 15px;
  font-family: inherit;
  color: var(--ink);
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.field input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.field__error {
  display: none;
  font-size: 12px;
  color: #c0392b;
}

.field__error.is-visible {
  display: block;
}

.pay-label {
  font-size: 13px;
  font-weight: 600;
  margin-bottom: var(--sp-3);
}

.pay-methods {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--sp-3);
  margin-bottom: var(--sp-5);
}

.pay-method {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px;
  font-size: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color 0.2s, background 0.2s;
}

.pay-method input {
  display: none;
}

.pay-method svg {
  width: 18px;
  height: 18px;
}

.pay-method.is-selected {
  border-color: var(--accent);
  background: var(--accent-soft);
}

.modal__submit {
  width: 100%;
}

.modal__fineprint {
  font-size: 12px;
  color: var(--ink-3);
  text-align: center;
  margin-top: var(--sp-3);
}

/* ---------- 条款页 ---------- */
.legal-page {
  padding: calc(76px + var(--sp-8)) 0 var(--sp-10);
}

.legal-head {
  max-width: 720px;
  margin-bottom: var(--sp-8);
}

.legal-head h1 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(36px, 5vw, 52px);
  margin-bottom: var(--sp-3);
}

.legal-head > p {
  color: var(--ink-2);
}

.legal-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: var(--sp-8);
  align-items: start;
}

.legal-toc {
  position: sticky;
  top: 104px;
  display: grid;
  gap: var(--sp-2);
  padding: var(--sp-5);
  background: var(--paper-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
}

.legal-toc a {
  font-size: 14px;
  color: var(--ink-2);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: background 0.2s, color 0.2s;
}

.legal-toc a:hover {
  background: var(--accent-soft);
  color: var(--accent-deep);
}

.legal-content {
  display: grid;
  gap: var(--sp-8);
}

.legal-content section h2 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 28px;
  padding-bottom: var(--sp-4);
  border-bottom: 1px solid var(--line);
  margin-bottom: var(--sp-5);
}

.legal-content section h3 {
  font-family: var(--serif);
  font-size: 19px;
  margin: var(--sp-5) 0 var(--sp-3);
}

.legal-content p {
  color: var(--ink-2);
  margin-bottom: var(--sp-4);
}

.legal-content ul {
  display: grid;
  gap: var(--sp-2);
  list-style: none;
  margin-bottom: var(--sp-4);
}

.legal-content li {
  position: relative;
  padding-left: 20px;
  color: var(--ink-2);
}

.legal-content li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
}

.legal-content a {
  color: var(--accent);
}

.legal-note {
  padding: var(--sp-4);
  background: var(--accent-soft);
  border-radius: var(--radius-sm);
}

.legal-note p {
  margin-bottom: 0;
}

/* ---------- 滚动进入动效 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(22px);
  transition: opacity 0.7s var(--ease-out), transform 0.7s var(--ease-out);
  transition-delay: calc(var(--d, 0) * 90ms);
  will-change: opacity, transform;
}

.reveal.is-visible {
  opacity: 1;
  transform: none;
}

/* ============================================================
   玻璃拟态覆盖（核心卡保留 blur，次级卡用半透明实色以保流畅）
   ============================================================ */
.pricing-card,
.service-card,
.quiz-card,
.buy-card {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.18), rgba(255, 255, 255, 0.05));
  -webkit-backdrop-filter: var(--glass-blur);
  backdrop-filter: var(--glass-blur);
  border-color: var(--glass-border);
  box-shadow: var(--glass-shadow);
}

.principle,
.teacher-person,
.faq-item,
.chapter {
  background: var(--paper-2);
  border-color: var(--line-soft);
}

.pricing-card:hover,
.service-card:hover,
.principle:hover {
  box-shadow: 0 24px 60px -28px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.72);
}

.pricing-card--hot {
  border-color: rgba(217, 160, 91, 0.55);
}

.quiz-option {
  background: var(--glass-strong);
  border-color: var(--glass-border);
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 1024px) {
  .section {
    padding: var(--sp-10) 0;
  }

  .nav {
    gap: var(--sp-5);
  }

  .footer-main {
    grid-template-columns: 1.4fr 1fr 1fr;
  }

  .footer-contact {
    grid-column: 1 / -1;
  }

  .course-layout {
    grid-template-columns: 1fr 320px;
  }
}

@media (max-width: 900px) {
  .nav {
    display: none;
  }

  .menu-toggle {
    display: flex;
  }

  .mobile-nav {
    display: block;
    position: fixed;
    top: 76px;
    left: 0;
    right: 0;
    background: var(--paper-2);
    border-bottom: 1px solid var(--line);
    overflow: hidden;
    max-height: 0;
    transition: max-height 0.35s var(--ease);
  }

  .mobile-nav.is-open {
    max-height: calc(100dvh - 76px);
    overflow-y: auto;
  }

  .mobile-nav__inner {
    display: grid;
    gap: 2px;
    padding: var(--sp-3) var(--gutter) var(--sp-6);
  }

  .mobile-nav__inner a {
    font-size: 17px;
    padding: 14px 0;
    border-bottom: 1px solid var(--line-soft);
  }

  .mobile-nav__inner .btn {
    margin-top: var(--sp-4);
  }

  .section-head {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
    margin-bottom: var(--sp-6);
  }

  .section-head__aside {
    justify-self: start;
    max-width: none;
  }

  .section-head__aside p {
    border-left: none;
    padding-left: 0;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-5);
  }

  .about-promises {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
  }

  .journey-step {
    grid-template-columns: auto 1fr;
    align-items: start;
  }

  .journey-step__tag {
    grid-column: 2;
    justify-self: start;
  }

  .principle-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
  }

  .pricing-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
  }

  .service-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
  }

  .service-card,
  .service-card--wide {
    grid-template-columns: 1fr;
    gap: var(--sp-5);
  }

  .service-card__side {
    border-left: none;
    border-top: 1px solid var(--line-soft);
    padding-left: 0;
    padding-top: var(--sp-5);
  }

  .teacher-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-6);
  }

  .teacher-list {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
  }

  .feedback-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-4);
  }

  .faq-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-6);
  }

  .faq-intro {
    position: static;
  }

  .cta-panel {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--sp-6);
  }

  .cta-actions {
    width: 100%;
    flex-direction: row;
    flex-wrap: wrap;
  }

  .course-hero-grid {
    grid-template-columns: 1fr;
    gap: var(--sp-6);
  }

  .course-layout {
    grid-template-columns: 1fr;
  }

  .buy-card {
    position: static;
  }

  .legal-layout {
    grid-template-columns: 1fr;
  }

  .legal-toc {
    position: static;
    grid-template-columns: repeat(4, auto);
  }
}

@media (max-width: 640px) {
  .section {
    padding: 44px 0;
  }

  .pwa-guide {
    display: block;
  }

  .header-inner {
    height: 64px;
  }

  .brand__cn,
  .logo__cn {
    font-size: 16px;
  }

  .header-actions .btn--sm,
  .header-actions .btn--primary {
    display: none;
  }

  .mobile-nav {
    top: 64px;
  }

  .hero {
    padding: calc(64px + 32px) 0 40px;
  }

  .hero__title {
    font-size: clamp(32px, 11vw, 42px);
  }

  .hero__br {
    display: none;
  }

  .hero__sub {
    font-size: 15px;
  }

  .hero__actions .btn {
    width: 100%;
  }

  .hero-stats {
    flex-wrap: wrap;
    gap: var(--sp-5) var(--sp-7);
  }

  .pricing-card {
    padding: 24px;
  }

  .pricing-card__price strong {
    font-size: 34px;
  }

  .quiz-card {
    padding: 24px 20px;
  }

  .service-card {
    padding: 24px;
  }

  .teacher-portrait__frame {
    aspect-ratio: 1 / 1;
  }

  .teacher-portrait__glyph {
    font-size: 110px;
  }

  .cta-panel {
    padding: 40px 24px;
  }

  .cta-actions {
    flex-direction: column;
  }

  .cta-actions .btn {
    width: 100%;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: var(--sp-6);
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--sp-3);
  }

  .course-page,
  .legal-page {
    padding-top: calc(64px + var(--sp-6));
  }

  .course-title {
    font-size: clamp(30px, 9vw, 40px);
  }

  .outcome-grid {
    grid-template-columns: 1fr;
  }

  .form-grid {
    grid-template-columns: 1fr;
  }

  .pay-methods {
    grid-template-columns: 1fr;
  }

  .legal-toc {
    grid-template-columns: 1fr 1fr;
  }

  .mobile-buy {
    display: flex;
    align-items: center;
    gap: var(--sp-4);
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 90;
    background: rgba(13, 11, 8, 0.92);
    -webkit-backdrop-filter: saturate(1.4) blur(14px);
    backdrop-filter: saturate(1.4) blur(14px);
    border-top: 1px solid var(--line);
    padding: 12px 20px calc(12px + env(safe-area-inset-bottom));
    transform: translateY(100%);
    transition: transform 0.35s var(--ease);
  }

  .mobile-buy.is-visible {
    transform: translateY(0);
  }

  .mobile-buy__price {
    display: flex;
    flex-direction: column;
    line-height: 1.2;
  }

  .mobile-buy__price strong {
    font-family: var(--serif);
    font-size: 24px;
  }

  .mobile-buy__price span {
    font-size: 11px;
    color: var(--ink-3);
  }

  .mobile-buy .btn {
    margin-left: auto;
    padding: 13px 24px;
  }

  .section-head h2,
  .about-intro h2,
  .faq-intro h2 {
    font-size: 28px;
  }

  .btn {
    padding: 14px 22px;
    font-size: 14px;
  }

  .principle h3,
  .journey-step__head h3,
  .about-promise h3 {
    font-size: 20px;
  }

  .principle p,
  .about-promise p,
  .journey-step__content > p,
  .service-card__desc {
    font-size: 14px;
  }

  section[id],
  [id] {
    scroll-margin-top: 80px;
  }

  .course-meta {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--sp-4);
  }
}

@media (max-width: 400px) {
  .hero__title {
    font-size: clamp(34px, 12vw, 42px);
  }

  .hero__actions .btn {
    padding: 15px 20px;
  }

  .quiz-option {
    padding: 15px 16px;
    font-size: 15px;
  }

  .about-intro h2,
  .section-head h2 {
    font-size: 28px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }

  .hero__title.is-split .char {
    opacity: 1;
    transform: none;
  }

  .is-tiltable {
    transform: none !important;
  }

  .marquee__track {
    animation: none;
  }
}