:root {
  color-scheme: light;
  --canvas: #f4e8cb;
  --canvas-soft: #fbf6e9;
  --panel: #cfe2df;
  --panel-strong: #174f4b;
  --primary: #217b74;
  --primary-hover: #135f5a;
  --text: #1e2523;
  --muted: #536661;
  --line: #d7c8a8;
  --white: #fffdf7;
  --shadow: 0 20px 60px rgb(23 79 75 / 12%);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP",
    "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text);
  background: var(--canvas);
  font-size: 16px;
  line-height: 1.75;
  overflow-wrap: anywhere;
}

a {
  color: inherit;
  text-underline-offset: 0.18em;
}

a:focus-visible {
  outline: 3px solid #2eb7dd;
  outline-offset: 4px;
  border-radius: 4px;
}

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  color: #f7f1df;
  background: rgb(23 79 75 / 96%);
  backdrop-filter: blur(14px);
}

.header-inner,
.footer-inner,
.page-shell,
.hero,
.latest-section,
.feature-section,
.about-section,
.cta-section {
  width: min(100% - 40px, 1120px);
  margin-inline: auto;
}

.header-inner {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 1.08rem;
  font-weight: 750;
  text-decoration: none;
}

.brand img {
  border-radius: 50%;
}

.site-header nav,
.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: flex-end;
  gap: 12px 24px;
}

.site-header nav a {
  color: #d1dfda;
  font-size: 0.88rem;
  font-weight: 650;
  text-decoration: none;
}

.site-header nav a:hover {
  color: #fff;
}

.hero {
  display: grid;
  min-height: 650px;
  grid-template-columns: 1.05fr 0.95fr;
  align-items: center;
  gap: clamp(40px, 8vw, 100px);
  padding-block: 88px 100px;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--primary);
  font-size: 0.74rem;
  font-weight: 800;
  letter-spacing: 0.16em;
}

.hero h1 {
  margin: 0;
  font-size: clamp(2.8rem, 7vw, 5.8rem);
  font-weight: 800;
  letter-spacing: -0.055em;
  line-height: 1.13;
}

.hero-lead {
  max-width: 620px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: clamp(1.03rem, 2vw, 1.2rem);
}

.hero-actions,
.join-actions,
.cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
}

.button {
  display: inline-flex;
  min-height: 50px;
  align-items: center;
  justify-content: center;
  padding: 11px 22px;
  border: 1px solid var(--panel-strong);
  border-radius: 999px;
  font-weight: 750;
  text-decoration: none;
  transition: transform 160ms ease, background-color 160ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button.primary {
  color: #fff;
  background: var(--panel-strong);
}

.button.primary:hover {
  background: var(--primary-hover);
}

.button.secondary {
  color: var(--panel-strong);
  background: transparent;
}

.button.secondary:hover {
  background: rgb(255 255 255 / 45%);
}

.hero-notes {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin: 24px 0 0;
  padding: 0;
  color: var(--muted);
  font-size: 0.86rem;
  list-style: none;
}

.hero-notes li::before {
  margin-right: 7px;
  color: var(--primary);
  content: "✓";
  font-weight: 900;
}

.conversation-visual {
  position: relative;
  min-height: 470px;
}

.conversation-visual::before,
.conversation-visual::after {
  position: absolute;
  border: 1px solid rgb(23 79 75 / 12%);
  border-radius: 50%;
  content: "";
}

.conversation-visual::before {
  inset: 8% 5% 8% 8%;
}

.conversation-visual::after {
  inset: 20% 17% 20% 20%;
}

.visual-mark {
  position: absolute;
  z-index: 2;
  inset: 50% auto auto 50%;
  display: grid;
  width: 190px;
  aspect-ratio: 1;
  translate: -50% -50%;
  place-items: center;
  border-radius: 50%;
  color: var(--canvas);
  background: var(--panel-strong);
  box-shadow: var(--shadow);
  font-size: 7rem;
  font-weight: 800;
  line-height: 1;
}

.message-card {
  position: absolute;
  z-index: 3;
  display: grid;
  width: min(300px, 68%);
  min-height: 88px;
  grid-template-columns: 38px 1fr;
  align-items: center;
  gap: 14px;
  padding: 18px;
  border: 1px solid rgb(23 79 75 / 9%);
  border-radius: 20px;
  background: var(--white);
  box-shadow: var(--shadow);
  font-size: 0.88rem;
}

.message-card span {
  width: 38px;
  aspect-ratio: 1;
  border-radius: 50%;
  background: var(--panel);
}

.card-a {
  top: 3%;
  right: 0;
}

.card-b {
  top: 46%;
  left: 0;
}

.card-c {
  right: 3%;
  bottom: 2%;
}

.latest-section,
.feature-section,
.about-section {
  padding-block: 88px;
}

.latest-section {
  width: min(100% - 40px, 1200px);
  padding-inline: clamp(22px, 4vw, 54px);
  border-radius: 34px;
  background: var(--panel-strong);
  color: #f6f0df;
}

.latest-section .eyebrow,
.latest-section .thread-meta {
  color: #a8c8c2;
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 34px;
}

.section-heading.centered {
  justify-content: center;
  text-align: center;
}

.section-heading h2,
.about-section h2,
.cta-section h2,
.join-card h2 {
  margin: 0;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  line-height: 1.3;
}

.text-link {
  flex: none;
  color: #dce9e5;
  font-size: 0.9rem;
  font-weight: 700;
}

.thread-feed {
  display: grid;
  margin: 0;
  padding: 0;
  gap: 10px;
  list-style: none;
}

.thread-feed a {
  display: grid;
  grid-template-columns: 90px 1fr auto;
  align-items: center;
  gap: 18px;
  padding: 18px 20px;
  border: 1px solid rgb(255 255 255 / 10%);
  border-radius: 16px;
  background: rgb(255 255 255 / 5%);
  text-decoration: none;
  transition: background-color 160ms ease, transform 160ms ease;
}

.thread-feed a:hover {
  transform: translateX(4px);
  background: rgb(255 255 255 / 10%);
}

.thread-category {
  color: #9ed5cc;
  font-size: 0.78rem;
  font-weight: 750;
}

.thread-meta {
  font-size: 0.78rem;
}

.empty-feed {
  color: var(--muted);
}

.latest-section .empty-feed {
  color: #bfd0cc;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.feature-grid article {
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: rgb(255 253 247 / 55%);
}

.feature-number {
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 850;
  letter-spacing: 0.12em;
}

.feature-grid h3 {
  margin: 14px 0 10px;
  font-size: 1.2rem;
}

.feature-grid p,
.about-copy,
.cta-section p,
.join-card p {
  color: var(--muted);
}

.feature-grid p {
  margin: 0;
}

.about-section {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 70px;
  border-top: 1px solid var(--line);
}

.about-copy p:first-child {
  margin-top: 0;
}

.cta-section {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 28px;
  margin-block: 54px 100px;
  padding: 34px;
  border-radius: 26px;
  background: var(--panel);
}

.cta-section img {
  border-radius: 50%;
}

.cta-section p {
  margin: 8px 0 0;
}

.cta-section .cta-actions {
  margin: 0;
}

.site-footer {
  color: #cbdad6;
  background: #103b38;
}

.footer-inner {
  display: flex;
  min-height: 100px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  font-size: 0.84rem;
}

.site-footer a {
  color: #cbdad6;
}

/* Thread pages */
.page-shell {
  padding-block: 42px 84px;
}

.thread-shell {
  max-width: 860px;
}

.breadcrumbs {
  display: flex;
  gap: 10px;
  margin-bottom: 24px;
  color: var(--muted);
  font-size: 0.82rem;
}

.thread-document {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 24px;
  background: rgb(255 253 247 / 70%);
  box-shadow: 0 16px 45px rgb(49 43 31 / 7%);
}

.thread-heading {
  padding: clamp(24px, 6vw, 48px);
  border-bottom: 1px solid var(--line);
}

.thread-heading h1 {
  margin: 14px 0 10px;
  font-size: clamp(1.8rem, 5vw, 3rem);
  line-height: 1.35;
}

.category-pill {
  display: inline-flex;
  padding: 4px 11px;
  border-radius: 999px;
  color: var(--panel-strong);
  background: var(--panel);
  font-size: 0.76rem;
  font-weight: 800;
}

.thread-summary {
  margin: 0;
  color: var(--muted);
  font-size: 0.84rem;
}

.post {
  padding: 26px clamp(22px, 6vw, 48px);
}

.post + .post {
  border-top: 1px solid var(--line);
}

.post header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px 12px;
  color: var(--muted);
  font-size: 0.78rem;
}

.post-number {
  color: var(--primary);
  font-weight: 850;
}

.post-body {
  margin-top: 14px;
  white-space: normal;
}

.post footer {
  min-height: 1.5em;
  margin-top: 12px;
  color: var(--primary);
  font-size: 0.8rem;
}

.post-media {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 10px;
  margin-top: 18px;
}

.post-media img {
  width: 100%;
  height: auto;
  max-height: 560px;
  border-radius: 12px;
  object-fit: contain;
  background: #e8ddc5;
}

.join-card {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 32px;
  margin-top: 26px;
  padding: 30px;
  border-radius: 22px;
  background: var(--panel);
}

.join-card h2 {
  font-size: clamp(1.4rem, 3vw, 2rem);
}

.join-card p {
  margin: 8px 0 0;
}

.join-actions {
  margin: 0;
}

.status-page {
  min-height: calc(100vh - 168px);
  padding-top: 100px;
  text-align: center;
}

.status-page h1 {
  margin: 0 0 12px;
  font-size: clamp(2rem, 6vw, 3.5rem);
}

.status-page .button {
  margin-top: 24px;
}

@media (max-width: 820px) {
  .hero {
    min-height: auto;
    grid-template-columns: 1fr;
    padding-block: 64px 76px;
  }

  .conversation-visual {
    min-height: 390px;
  }

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

  .about-section,
  .cta-section,
  .join-card {
    grid-template-columns: 1fr;
  }

  .cta-actions,
  .join-actions {
    margin-top: 8px;
  }

  .thread-feed a {
    grid-template-columns: 74px 1fr;
  }

  .thread-meta {
    grid-column: 2;
  }
}

@media (max-width: 600px) {
  .header-inner,
  .footer-inner,
  .page-shell,
  .hero,
  .latest-section,
  .feature-section,
  .about-section,
  .cta-section {
    width: min(100% - 28px, 1120px);
  }

  .header-inner {
    min-height: 60px;
  }

  .site-header nav a:first-child {
    display: none;
  }

  .site-header nav {
    gap: 14px;
  }

  .site-header nav a {
    font-size: 0.78rem;
  }

  .brand {
    font-size: 0;
  }

  .brand img {
    width: 34px;
    height: 34px;
  }

  .hero h1 {
    font-size: clamp(2.7rem, 15vw, 4.4rem);
  }

  .hero-actions .button,
  .cta-actions .button,
  .join-actions .button {
    width: 100%;
  }

  .conversation-visual {
    min-height: 330px;
  }

  .visual-mark {
    width: 140px;
    font-size: 5rem;
  }

  .message-card {
    min-height: 70px;
    padding: 13px;
    font-size: 0.76rem;
  }

  .latest-section,
  .feature-section,
  .about-section {
    padding-block: 62px;
  }

  .latest-section {
    padding-inline: 18px;
    border-radius: 22px;
  }

  .section-heading {
    align-items: start;
  }

  .thread-feed a {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .thread-meta {
    grid-column: 1;
  }

  .feature-grid article,
  .cta-section,
  .join-card {
    padding: 22px;
  }

  .cta-section img {
    width: 68px;
    height: 68px;
  }

  .footer-inner {
    min-height: 130px;
    flex-direction: column;
    justify-content: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .button,
  .thread-feed a {
    transition: none;
  }
}