:root {
  --page: #ffffff;
  --ink: #050505;
  --muted: #4b4f56;
  --soft: #8c939c;
  --line: #d8dce1;
  --panel: #f4f5f6;
  --panel-strong: #eceff2;
  --accent: #2f7d95;
  --red: #b7332c;
  --max: 1480px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--page);
  font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif;
  line-height: 1.55;
}

button,
input {
  font: inherit;
}

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

.site-header {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px 48px 16px;
}

.brand {
  display: inline-flex;
  flex-direction: column;
  color: inherit;
  text-decoration: none;
}

.brand-title {
  color: #4f565f;
  font-size: clamp(28px, 3vw, 38px);
  font-weight: 400;
  line-height: 1.05;
  letter-spacing: 0;
}

.brand-subtitle {
  margin-top: 4px;
  color: #000;
  font-size: clamp(18px, 2vw, 24px);
  font-weight: 400;
  line-height: 1.2;
}

.main-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 24px 56px;
  margin-top: 28px;
  padding-left: 24px;
}

.nav-link {
  border: 0;
  padding: 0;
  color: #444b54;
  background: transparent;
  cursor: pointer;
  font-size: clamp(18px, 2vw, 25px);
  line-height: 1.25;
  text-align: left;
  text-transform: uppercase;
}

.nav-link:hover,
.nav-link.is-active {
  color: #000;
}

#app {
  max-width: var(--max);
  margin: 0 auto;
  padding: 24px 48px 60px;
}

.home-kicker {
  margin: 24px 0 22px;
  color: #8c939c;
  font-size: 21px;
  font-weight: 700;
}

.section-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.section-card {
  position: relative;
  min-height: 260px;
  border: 0;
  padding: 0;
  background: #e8ecef;
  cursor: pointer;
  overflow: hidden;
  text-align: left;
}

.section-card:nth-child(4),
.section-card:nth-child(5) {
  min-height: 360px;
}

.section-card img {
  width: 100%;
  height: 100%;
  min-height: inherit;
  object-fit: cover;
  transition: transform 360ms ease, filter 360ms ease;
}

.section-card:hover img {
  transform: scale(1.035);
  filter: contrast(1.05);
}

.section-label {
  position: absolute;
  left: 18px;
  right: 18px;
  bottom: 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  color: #fff;
  text-shadow: 0 2px 14px rgba(0, 0, 0, 0.55);
}

.section-label strong {
  font-size: clamp(21px, 2.2vw, 31px);
  font-weight: 700;
  line-height: 1.12;
}

.section-label span {
  font-size: 14px;
  font-weight: 700;
}

.section-page {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  gap: 42px;
  align-items: start;
}

.section-crumb {
  color: #3f4650;
  font-size: 23px;
  letter-spacing: 4px;
  text-transform: uppercase;
}

.section-title {
  margin: 30px 0 16px;
  font-size: clamp(40px, 5.2vw, 66px);
  line-height: 1.05;
  letter-spacing: 0;
}

.title-suffix {
  display: inline-block;
  margin-left: 0.18em;
  font-size: 0.82em;
  font-weight: inherit;
  line-height: inherit;
}

.section-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-bottom: 36px;
  color: var(--muted);
  font-size: 16px;
  font-weight: 700;
}

.week-rail {
  position: sticky;
  top: 18px;
  padding-top: 106px;
}

.week-rail::before {
  content: "";
  position: absolute;
  top: 125px;
  bottom: 12px;
  left: 23px;
  width: 1px;
  background: var(--line);
}

.week-button {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 48px 1fr;
  align-items: center;
  width: 100%;
  border: 0;
  margin: 0 0 26px;
  padding: 0;
  color: var(--muted);
  background: transparent;
  cursor: pointer;
  text-align: left;
}

.week-icon {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border: 1px solid #aeb5bd;
  border-radius: 50%;
  background: #fff;
  color: #333a42;
  font-size: 16px;
  font-weight: 700;
}

.week-button span:last-child {
  padding-left: 12px;
  font-size: 17px;
  font-weight: 700;
}

.week-button:hover,
.week-button.is-active {
  color: #000;
}

.week-button.is-active .week-icon {
  border-color: #111;
  color: #fff;
  background: #111;
}

.conversation-list {
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.conversation {
  border-top: 1px solid var(--line);
  padding-top: 20px;
}

.conversation-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: start;
  width: 100%;
  border: 0;
  padding: 0;
  background: transparent;
  cursor: pointer;
  text-align: left;
}

.conversation-title {
  margin: 0;
  font-size: clamp(24px, 2.4vw, 36px);
  line-height: 1.22;
}

.conversation-sub {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 10px;
  color: var(--soft);
  font-size: 14px;
  font-weight: 700;
}

.toggle-icon {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  color: #1e2328;
  font-size: 24px;
  line-height: 1;
}

.conversation.is-open .toggle-icon {
  background: #111;
  color: #fff;
}

.conversation-body {
  display: none;
  padding: 24px 0 8px;
}

.conversation.is-open .conversation-body {
  display: block;
}

.preface {
  margin-bottom: 22px;
  color: var(--muted);
  font-size: 16px;
}

.round {
  display: grid;
  grid-template-columns: 160px minmax(0, 1fr);
  gap: 22px;
  border-top: 1px solid var(--panel-strong);
  padding: 24px 0;
}

.round-index {
  color: #555d67;
  font-size: 18px;
  font-weight: 700;
}

.round-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.process-block {
  min-width: 0;
}

.process-block h4 {
  margin: 0 0 10px;
  color: #111;
  font-size: 18px;
  line-height: 1.3;
}

.process-text {
  margin: 0;
  color: #1b1f24;
  font-size: 16px;
  white-space: pre-wrap;
}

.image-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 8px;
  margin-top: 14px;
}

.image-strip img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  background: var(--panel);
}

.empty-note {
  color: var(--soft);
  font-size: 15px;
}

.site-footer {
  max-width: var(--max);
  margin: 0 auto;
  padding: 18px 48px 34px;
  display: flex;
  justify-content: center;
  gap: 10px;
  color: #000;
  font-size: 14px;
}

.back-link {
  display: inline-block;
  margin-bottom: 18px;
  color: #3f4650;
  text-decoration: none;
  font-size: 18px;
  font-weight: 700;
}

@media (max-width: 980px) {
  .site-header,
  #app,
  .site-footer {
    padding-left: 24px;
    padding-right: 24px;
  }

  .main-nav {
    padding-left: 0;
    gap: 16px 28px;
  }

  .section-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .section-page {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .week-rail {
    position: static;
    display: flex;
    gap: 12px;
    padding-top: 0;
    overflow-x: auto;
  }

  .week-rail::before {
    display: none;
  }

  .week-button {
    grid-template-columns: 42px max-content;
    width: auto;
    margin: 0 0 18px;
  }

  .week-icon {
    width: 42px;
    height: 42px;
  }

  .round,
  .round-columns {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .site-header {
    padding-top: 20px;
  }

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

  .section-card,
  .section-card:nth-child(4),
  .section-card:nth-child(5) {
    min-height: 260px;
  }

  .conversation-header {
    grid-template-columns: 1fr;
  }

  .toggle-icon {
    width: 100%;
  }

  .site-footer {
    flex-direction: column;
    align-items: center;
  }
}