.page-contact {
  --co-rule: rgba(199, 207, 204, 0.22);
  --co-rule-soft: rgba(199, 207, 204, 0.12);
  --co-cut: 16px;
}

/* ---------- 顶部区块 ---------- */
.page-contact .co-top {
  padding-bottom: clamp(48px, 7vw, 88px);
}

.page-contact .co-hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(22px, 3vw, 36px);
  align-items: end;
  padding-block: clamp(24px, 5vw, 48px) clamp(20px, 4vw, 36px);
}

.page-contact .co-hero__eyebrow {
  margin: 0 0 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--cyan);
}

.page-contact .co-hero__title {
  margin: 0 0 18px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(29px, 5.4vw, 56px);
  line-height: 1.14;
  letter-spacing: -0.02em;
  color: var(--mist);
}

.page-contact .co-hero__lede {
  margin: 0;
  max-width: 60ch;
  font-size: 17px;
  line-height: 1.78;
  color: var(--silver);
}

.page-contact .co-coord {
  border-top: 1px solid var(--co-rule);
  padding-top: 6px;
}

.page-contact .co-coord__row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding: 11px 0;
  border-bottom: 1px solid var(--co-rule-soft);
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.04em;
}

.page-contact .co-coord__key {
  color: var(--silver-dim);
}

.page-contact .co-coord__val {
  color: var(--mist);
  text-align: right;
}

.page-contact .co-coord__val--cyan {
  color: var(--cyan);
}

.page-contact .co-coord__val--amber {
  color: var(--amber);
}

/* ---------- 出血图带 ---------- */
.page-contact .co-strip {
  margin: clamp(20px, 3.5vw, 40px) 0 clamp(40px, 6vw, 72px);
}

.page-contact .co-strip img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(
    var(--co-cut) 0,
    100% 0,
    100% calc(100% - var(--co-cut)),
    calc(100% - var(--co-cut)) 100%,
    0 100%,
    0 var(--co-cut)
  );
  filter: saturate(0.42) contrast(1.06) brightness(0.92);
}

.page-contact .co-strip__cap {
  margin: 12px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.04em;
  line-height: 1.7;
  color: var(--silver-dim);
}

/* ---------- 四类合作方向 ---------- */
.page-contact .co-directions-head {
  margin-bottom: clamp(20px, 3vw, 32px);
}

.page-contact .co-directions {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(14px, 2vw, 22px);
}

.page-contact .co-dir {
  position: relative;
  overflow: hidden;
  padding: clamp(22px, 2.6vw, 30px) clamp(18px, 2vw, 24px) clamp(20px, 2.4vw, 26px);
  background: var(--ink-mid);
  clip-path: polygon(
    var(--co-cut) 0,
    100% 0,
    100% calc(100% - var(--co-cut)),
    calc(100% - var(--co-cut)) 100%,
    0 100%,
    0 var(--co-cut)
  );
  transition: background-color var(--dur) var(--ease);
}

.page-contact .co-dir:hover {
  background: #175a4c;
}

.page-contact .co-dir::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 46px;
  height: 3px;
  background: var(--cyan);
  transition: width var(--dur) var(--ease);
}

.page-contact .co-dir::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  width: 46px;
  height: 46px;
  pointer-events: none;
  background-image: repeating-linear-gradient(
    45deg,
    rgba(199, 207, 204, 0.1) 0 1px,
    transparent 1px 5px
  );
}

.page-contact .co-dir:hover::before,
.page-contact .co-dir:focus-within::before {
  width: 100%;
}

.page-contact .co-dir--amber::before {
  background: var(--amber);
}

.page-contact .co-dir__no {
  display: block;
  margin-bottom: 12px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--cyan);
}

.page-contact .co-dir--amber .co-dir__no {
  color: var(--amber);
}

.page-contact .co-dir__title {
  margin: 0 0 8px;
  font-family: var(--font-title);
  font-weight: 900;
  font-size: clamp(19px, 2.4vw, 23px);
  letter-spacing: -0.01em;
  color: var(--mist);
}

.page-contact .co-dir__for {
  margin: 0 0 12px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--silver-dim);
}

.page-contact .co-dir__desc {
  margin: 0;
  font-size: 15px;
  line-height: 1.76;
  color: var(--silver);
}

.page-contact .co-dir__link {
  display: inline-block;
  margin-top: 18px;
  padding-bottom: 2px;
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.06em;
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(41, 240, 210, 0.34);
  transition: border-color var(--dur) var(--ease), color var(--dur) var(--ease);
}

.page-contact .co-dir__link:hover,
.page-contact .co-dir__link:focus-visible {
  border-color: var(--cyan);
}

.page-contact .co-dir--amber .co-dir__link {
  color: var(--amber);
  border-bottom-color: rgba(255, 166, 43, 0.34);
}

.page-contact .co-dir--amber .co-dir__link:hover,
.page-contact .co-dir--amber .co-dir__link:focus-visible {
  border-color: var(--amber);
}

/* ---------- 中段：流程与稿件 ---------- */
.page-contact .co-mid {
  padding-block: clamp(48px, 7vw, 88px);
}

.page-contact .co-flow {
  list-style: none;
  margin: 0 0 clamp(40px, 6vw, 72px);
  padding: 0;
}

.page-contact .co-step {
  position: relative;
  padding: 4px 0 26px 30px;
  border-left: 1px solid var(--silver);
}

.page-contact .co-step:last-child {
  padding-bottom: 0;
}

.page-contact .co-step::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 8px;
  width: 9px;
  height: 9px;
  background: var(--ink-mid);
  transform: rotate(45deg);
  transition: background-color var(--dur) var(--ease);
}

.page-contact .co-step:hover::before {
  background: var(--amber-deep);
}

.page-contact .co-step__idx {
  display: block;
  margin-bottom: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--ink-mid);
}

.page-contact .co-step__title {
  margin: 0 0 8px;
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 19px;
  letter-spacing: -0.01em;
  color: var(--graphite);
}

.page-contact .co-step__desc {
  margin: 0;
  max-width: 62ch;
  font-size: 16px;
  line-height: 1.78;
  color: var(--graphite);
}

.page-contact .co-step__time {
  margin: 10px 0 0;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--amber-deep);
}

.page-contact .co-submit-head {
  margin-bottom: clamp(18px, 2.6vw, 28px);
}

.page-contact .co-split {
  display: grid;
  grid-template-columns: 1fr;
  gap: clamp(26px, 3.4vw, 44px);
}

.page-contact .co-submit__title {
  margin: 0 0 10px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--ink-mid);
  font-family: var(--font-title);
  font-weight: 900;
  font-size: 21px;
  letter-spacing: -0.01em;
  color: var(--graphite);
}

.page-contact .co-submit__col--alt .co-submit__title {
  border-bottom-color: var(--amber-deep);
}

.page-contact .co-submit__list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.page-contact .co-submit__list li {
  position: relative;
  padding: 13px 0 13px 20px;
  border-bottom: 1px solid rgba(42, 51, 49, 0.1);
  font-size: 16px;
  line-height: 1.76;
  color: var(--graphite);
}

.page-contact .co-submit__list li strong {
  font-weight: 700;
  color: var(--ink-deep);
}

.page-contact .co-submit__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 22px;
  width: 7px;
  height: 7px;
  background: var(--ink-mid);
}

.page-contact .co-submit__col--alt .co-submit__list li::before {
  background: var(--amber-deep);
}

/* ---------- 下段：联系与问答 ---------- */
.page-contact .co-bottom {
  padding-block: clamp(48px, 7vw, 88px);
}

.page-contact .co-channels {
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.page-contact .co-channel {
  padding: 18px 20px 20px;
  background: rgba(20, 81, 69, 0.55);
  border-left: 3px solid var(--cyan);
}

.page-contact .co-channel--amber {
  border-left-color: var(--amber);
}

.page-contact .co-channel__key {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--silver-dim);
}

.page-contact .co-channel__val {
  margin: 0;
  font-family: var(--font-mono);
  font-size: clamp(15px, 2vw, 18px);
  letter-spacing: 0.02em;
  line-height: 1.6;
  color: var(--mist);
  overflow-wrap: anywhere;
}

.page-contact .co-channel--amber .co-channel__val {
  color: var(--amber);
}

.page-contact .co-channel__hint {
  margin: 8px 0 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--silver-dim);
}

.page-contact .co-contact__note {
  margin: 22px 0 0;
  max-width: 64ch;
  font-size: 15px;
  line-height: 1.8;
  color: var(--silver);
}

.page-contact .co-contact__note a {
  color: var(--cyan);
  text-decoration: none;
  border-bottom: 1px solid rgba(41, 240, 210, 0.34);
  transition: border-color var(--dur) var(--ease);
}

.page-contact .co-contact__note a:hover,
.page-contact .co-contact__note a:focus-visible {
  border-color: var(--cyan);
}

.page-contact .co-contact__figure {
  margin: 0;
  align-self: start;
}

.page-contact .co-contact__figure img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: auto;
  object-fit: cover;
  clip-path: polygon(
    0 0,
    calc(100% - var(--co-cut)) 0,
    100% var(--co-cut),
    100% 100%,
    var(--co-cut) 100%,
    0 calc(100% - var(--co-cut))
  );
  filter: saturate(0.4) contrast(1.06) brightness(0.9);
}

.page-contact .co-faq-head {
  margin-top: clamp(44px, 6vw, 76px);
}

.page-contact .co-faq {
  border-top: 1px solid var(--co-rule);
}

.page-contact .co-faq__item {
  border-bottom: 1px solid var(--co-rule-soft);
}

.page-contact .co-faq__q {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 0;
  cursor: pointer;
  list-style: none;
  font-family: var(--font-title);
  font-weight: 700;
  font-size: 17px;
  line-height: 1.6;
  color: var(--mist);
  transition: color var(--dur) var(--ease);
}

.page-contact .co-faq__q::-webkit-details-marker {
  display: none;
}

.page-contact .co-faq__q::after {
  content: "+";
  flex: none;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--cyan);
  transition: transform var(--dur) var(--ease);
}

.page-contact .co-faq__item[open] .co-faq__q::after {
  transform: rotate(45deg);
}

.page-contact .co-faq__q:hover {
  color: var(--cyan);
}

.page-contact .co-faq__a {
  max-width: 68ch;
  padding: 0 0 22px;
  font-size: 16px;
  line-height: 1.8;
  color: var(--silver);
}

.page-contact .co-cta {
  margin-top: clamp(40px, 5vw, 64px);
  padding-top: clamp(28px, 4vw, 40px);
  border-top: 1px solid var(--co-rule);
  display: grid;
  gap: 20px;
}

.page-contact .co-cta__text {
  margin: 0;
  max-width: 60ch;
  font-size: 17px;
  line-height: 1.78;
  color: var(--mist);
}

.page-contact .co-cta__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

/* ---------- 响应式 ---------- */
@media (min-width: 560px) {
  .page-contact .co-directions {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-contact .co-channels {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-contact .co-channel--wide {
    grid-column: 1 / -1;
  }
}

@media (min-width: 900px) {
  .page-contact .co-hero {
    grid-template-columns: minmax(0, 1.7fr) minmax(0, 1fr);
  }

  .page-contact .co-split {
    grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
    align-items: start;
  }

  .page-contact .co-submit {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-contact .co-coord {
    border-top: 1px solid var(--co-rule);
  }
}

@media (min-width: 1024px) {
  .page-contact .co-directions {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .page-contact .co-flow {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0 clamp(16px, 2vw, 30px);
    padding-top: 30px;
    border-top: 1px solid var(--silver);
  }

  .page-contact .co-step {
    padding: 0;
    border-left: 0;
  }

  .page-contact .co-step::before {
    left: 0;
    top: -36px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .page-contact .co-dir,
  .page-contact .co-dir::before,
  .page-contact .co-dir__link,
  .page-contact .co-step::before,
  .page-contact .co-faq__q,
  .page-contact .co-faq__q::after,
  .page-contact .co-contact__note a {
    transition: none;
  }
}