.page-contact {
  --fb-rail-w: 340px;
  --fb-gap: clamp(32px, 5vw, 64px);
  --fb-card-line: rgba(28, 42, 68, 0.95);
  background: var(--c-void);
  color: var(--c-text);
  padding-top: clamp(20px, 3vw, 40px);
  padding-bottom: clamp(64px, 9vw, 120px);
  overflow-x: clip;
}

.page-contact .breadcrumb {
  margin-bottom: clamp(22px, 4vw, 44px);
}

.page-contact .contact-hero {
  max-width: 820px;
}

.page-contact .contact-hero .eyebrow {
  color: var(--c-cyan);
}

.page-contact .contact-hero h1 {
  margin: 14px 0 0;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(2rem, 7vw, 4.1rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
  color: var(--c-text);
}

.page-contact .contact-hero .lead {
  margin: 18px 0 0;
  max-width: 40em;
  font-size: clamp(1rem, 1.5vw, 1.125rem);
  line-height: 1.78;
  color: var(--c-muted);
}

.page-contact .contact-hero .chip-row {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.page-contact .fb-shell {
  margin-top: clamp(38px, 6vw, 76px);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(36px, 5vw, 56px);
}

.page-contact .fb-main {
  min-width: 0;
}

.page-contact .fb-steps {
  position: relative;
  display: grid;
  gap: var(--fb-gap);
}

.page-contact .fb-step {
  min-width: 0;
}

.page-contact .fb-step__head {
  display: flex;
  align-items: flex-start;
  gap: 14px;
}

.page-contact .fb-step__head .chapter-num {
  flex: none;
  min-width: 2.1em;
  font-family: var(--font-mono);
  font-size: clamp(1.7rem, 5vw, 2.75rem);
  line-height: 0.9;
  letter-spacing: -0.03em;
  color: rgba(69, 224, 224, 0.32);
  -webkit-text-stroke: 1px var(--c-cyan);
}

.page-contact .fb-step__head .chapter-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.3rem, 3.4vw, 1.9rem);
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.page-contact .fb-step__head .chapter-lede {
  margin: 10px 0 0;
  max-width: 40em;
  font-size: 0.96rem;
  line-height: 1.75;
  color: var(--c-muted);
}

.page-contact .fb-step__foot {
  margin: 20px 0 0;
  padding-left: 14px;
  border-left: 2px solid var(--c-line);
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--c-muted);
}

.page-contact .media-frame {
  margin: 24px 0 0;
  border: 1px solid var(--c-line);
  border-radius: 0;
  overflow: hidden;
  background: var(--c-night);
}

.page-contact .media-frame img {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
}

/* 折叠问答（反馈类型） */
.page-contact .fold {
  margin-top: 24px;
  display: grid;
  gap: 10px;
}

.page-contact .fold__item {
  border: 1px solid var(--c-line);
  background: var(--c-panel);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-contact .fold__item:hover {
  border-color: rgba(69, 224, 224, 0.5);
  transform: translateY(-2px);
}

.page-contact .fold__trigger {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 18px;
  background: transparent;
  border: 0;
  color: var(--c-text);
  font: inherit;
  font-weight: 700;
  font-size: 0.98rem;
  text-align: left;
  cursor: pointer;
}

.page-contact .fold__trigger:focus-visible {
  outline: 2px solid var(--c-focus);
  outline-offset: 2px;
}

.page-contact .fold__icon {
  flex: none;
  width: 10px;
  height: 10px;
  border-right: 1.5px solid var(--c-cyan);
  border-bottom: 1.5px solid var(--c-cyan);
  transform: rotate(45deg);
  transition: transform var(--dur) var(--ease);
}

.page-contact .fold__trigger[aria-expanded="true"] .fold__icon {
  transform: rotate(-135deg);
}

.page-contact .fold__panel {
  padding: 0 18px 18px;
  color: var(--c-muted);
  font-size: 0.93rem;
  line-height: 1.78;
}

.page-contact .fold__panel p {
  margin: 0;
}

/* 随信信息 */
.page-contact .info-grid {
  margin-top: 24px;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 12px;
}

.page-contact .info-card {
  padding: 16px 16px 16px 18px;
  background: rgba(16, 26, 46, 0.72);
  border: 1px solid var(--c-line);
  border-left: 2px solid var(--c-cyan);
  transition: border-color var(--dur) var(--ease), transform var(--dur) var(--ease);
}

.page-contact .info-card:hover {
  border-color: rgba(69, 224, 224, 0.55);
  transform: translateY(-2px);
}

.page-contact .info-card__key {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--c-cyan);
}

.page-contact .info-card p {
  margin: 0;
  font-size: 0.92rem;
  line-height: 1.72;
  color: var(--c-text);
}

/* 渠道说明 */
.page-contact .channel-notes {
  margin-top: 24px;
  border-top: 1px solid var(--c-line);
}

.page-contact .channel-note-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 6px;
  padding: 18px 0;
  border-bottom: 1px solid var(--c-line);
}

.page-contact .channel-note-row__key {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  color: var(--c-amber);
}

.page-contact .channel-note-row p {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.78;
  color: var(--c-muted);
}

/* 订阅 */
.page-contact .subscribe-card {
  margin-top: 24px;
  padding: clamp(20px, 4vw, 30px);
  border: 1px solid rgba(69, 224, 224, 0.28);
}

.page-contact .subscribe-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 14px;
}

.page-contact .subscribe-steps li {
  display: grid;
  grid-template-columns: 2.6em minmax(0, 1fr);
  gap: 10px;
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--c-text);
}

.page-contact .subscribe-steps .mono {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  color: var(--c-cyan);
  padding-top: 0.28em;
}

.page-contact .subscribe-card__note {
  margin: 20px 0 0;
  padding-top: 16px;
  border-top: 1px dashed rgba(69, 224, 224, 0.25);
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--c-muted);
}

.page-contact .subscribe-card__note a {
  color: var(--c-cyan);
  text-decoration: underline;
  text-underline-offset: 3px;
}

/* 延伸阅读 */
.page-contact .fb-more {
  margin-top: clamp(36px, 5vw, 56px);
  padding: clamp(20px, 4vw, 28px);
  border: 1px solid var(--c-line);
  background: var(--c-night);
}

.page-contact .fb-more__title {
  margin: 0 0 16px;
  font-size: 1.02rem;
  font-weight: 800;
  letter-spacing: -0.01em;
}

.page-contact .fb-more__list {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 12px;
}

.page-contact .fb-more__list li {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 4px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--c-line);
}

.page-contact .fb-more__list li:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-contact .fb-more__list a {
  color: var(--c-cyan);
  font-weight: 700;
  font-size: 0.94rem;
  text-decoration: none;
}

.page-contact .fb-more__list a:hover {
  text-decoration: underline;
  text-underline-offset: 4px;
}

.page-contact .fb-more__list a:focus-visible {
  outline: 2px solid var(--c-focus);
  outline-offset: 3px;
}

.page-contact .fb-more__list span {
  font-size: 0.86rem;
  line-height: 1.7;
  color: var(--c-muted);
}

/* 右侧渠道卡片 */
.page-contact .channel-rail {
  min-width: 0;
}

.page-contact .channel-card {
  position: relative;
  overflow: hidden;
  padding: clamp(20px, 3vw, 26px);
  border: 1px solid rgba(240, 178, 60, 0.3);
  background: var(--c-panel);
}

.page-contact .channel-card__bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.16;
  pointer-events: none;
}

.page-contact .channel-card__inner {
  position: relative;
  z-index: 1;
}

.page-contact .channel-card__kicker {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: var(--c-amber);
}

.page-contact .channel-card__title {
  margin: 8px 0 18px;
  font-size: 1.2rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--c-text);
}

.page-contact .channel-list {
  margin: 0;
  display: grid;
  gap: 14px;
}

.page-contact .channel-list__row {
  padding-bottom: 12px;
  border-bottom: 1px solid var(--c-line);
}

.page-contact .channel-list__row:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.page-contact .channel-list dt {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  color: var(--c-muted);
  margin-bottom: 5px;
}

.page-contact .channel-list dd {
  margin: 0;
  font-size: 0.94rem;
  line-height: 1.6;
  word-break: break-word;
  color: var(--c-text);
}

.page-contact .channel-list dd.mono {
  font-family: var(--font-mono);
  font-size: 0.86rem;
  letter-spacing: 0.01em;
}

.page-contact .channel-card__note {
  margin: 18px 0 0;
  padding-top: 14px;
  border-top: 1px dashed var(--c-line);
  font-size: 0.8rem;
  line-height: 1.72;
  color: var(--c-muted);
}

.page-contact .rail-links {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 2px;
}

.page-contact .rail-links a {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 9px 0;
  font-size: 0.88rem;
  color: var(--c-text);
  text-decoration: none;
  border-bottom: 1px solid rgba(28, 42, 68, 0.7);
  transition: color var(--dur) var(--ease);
}

.page-contact .rail-links a:hover {
  color: var(--c-cyan);
}

.page-contact .rail-links a:focus-visible {
  outline: 2px solid var(--c-focus);
  outline-offset: 3px;
}

.page-contact .rail-links .mono {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--c-cyan);
  letter-spacing: 0.08em;
}

@media (min-width: 640px) {
  .page-contact .info-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-contact .fb-more__list li {
    grid-template-columns: 9em minmax(0, 1fr);
    align-items: baseline;
    gap: 14px;
  }

  .page-contact .channel-note-row {
    grid-template-columns: 6.5em minmax(0, 1fr);
    gap: 16px;
    align-items: start;
  }

  .page-contact .channel-note-row__key {
    padding-top: 0.28em;
  }
}

@media (min-width: 760px) {
  .page-contact .fb-steps::before {
    content: "";
    position: absolute;
    left: 1.05em;
    top: 0.4em;
    bottom: 0.4em;
    width: 1px;
    background: linear-gradient(180deg, var(--c-cyan) 0%, rgba(69, 224, 224, 0.18) 55%, transparent 100%);
    pointer-events: none;
  }

  .page-contact .fb-step__head {
    gap: 22px;
  }

  .page-contact .fb-step__body,
  .page-contact .fb-step > .fold,
  .page-contact .fb-step > .info-grid,
  .page-contact .fb-step > .channel-notes,
  .page-contact .fb-step > .subscribe-card,
  .page-contact .fb-step > .media-frame,
  .page-contact .fb-step > .fb-step__foot {
    margin-left: calc(2.1em + 22px);
  }
}

@media (min-width: 960px) {
  .page-contact .fb-shell {
    grid-template-columns: minmax(0, 1fr) var(--fb-rail-w);
    align-items: start;
    gap: clamp(40px, 4vw, 68px);
  }

  .page-contact .channel-rail {
    position: sticky;
    top: calc(var(--header-h) + 24px);
  }

  .page-contact .contact-hero h1 {
    max-width: 14em;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-contact .fold__item,
  .page-contact .info-card,
  .page-contact .fold__icon,
  .page-contact .rail-links a {
    transition: none;
  }

  .page-contact .fold__item:hover,
  .page-contact .info-card:hover {
    transform: none;
  }
}
<<<END>>>