:root {
  --bg: #f0f2f5;
  --panel: #ffffff;
  --line: #d9dde3;
  --text: #1c1e21;
  --muted: #65676b;
  --blue: #1877f2;
  --blue-dark: #0f5ec7;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
}

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

.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(360px, 640px) minmax(0, 1fr);
  gap: 12px 18px;
  align-items: start;
  padding: 8px 18px 10px;
  background: var(--panel);
  border-bottom: 1px solid var(--line);
}

.top-left,
.top-center,
.top-actions,
.brand,
.brand-stack,
.account-stack,
.header-tabs,
.profile-pill,
.post-author,
.engagement-row,
.composer-row,
.composer-tools,
.comment-form,
.view-nav,
.feed-toolbar {
  display: flex;
  align-items: center;
}

.top-actions {
  justify-content: flex-end;
  gap: 8px;
  align-self: start;
}

.account-stack {
  display: grid;
  justify-items: center;
  gap: 4px;
}

.top-left {
  gap: 10px;
  align-items: center;
  min-width: 0;
}

.brand-stack {
  display: grid;
  gap: 4px;
  min-width: 0;
}

.top-center {
  display: grid;
  justify-items: center;
  gap: 6px;
  min-width: 0;
  width: 100%;
}

.brand {
  gap: 8px;
  justify-content: flex-start;
  font-size: 18px;
  font-weight: 800;
  color: var(--blue);
  white-space: nowrap;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  color: white;
  background: var(--blue);
}

.profile-pill {
  gap: 8px;
  padding: 4px 8px 4px 4px;
  border-radius: 999px;
}

.profile-pill:hover,
.icon-btn:hover,
.view-nav a:hover,
.header-tabs a:hover {
  background: #e4e6eb;
}

.profile-pill span:last-child,
.post-author span:last-child {
  display: grid;
  gap: 2px;
}

small,
.meta,
.hint,
.feed-toolbar p,
.engagement-row span {
  color: var(--muted);
}

.avatar {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 50%;
  color: white;
  font-weight: 800;
  text-transform: uppercase;
  flex: 0 0 auto;
}

.avatar.small {
  width: 38px;
  height: 38px;
}

.searchbar input,
.login-strip input,
input,
textarea,
select {
  border: 1px solid var(--line);
  border-radius: 20px;
  background: #f0f2f5;
  color: var(--text);
  font: inherit;
}

.searchbar input {
  width: min(620px, 100%);
  padding: 8px 14px;
}

.login-strip {
  display: flex;
  gap: 8px;
  width: auto;
  flex: 0 1 auto;
  min-width: 0;
}

.login-strip input {
  width: 160px;
  padding: 9px 12px;
}

.login-strip button,
.primary-btn,
.icon-btn,
.ghost-btn,
.comment-form button {
  border: 0;
  border-radius: 20px;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
}

.login-strip button,
.primary-btn {
  background: var(--blue);
  color: white;
  padding: 10px 18px;
}

.primary-btn:hover { background: var(--blue-dark); }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 34px;
  padding: 8px 14px;
  background: #e4e6eb;
  color: var(--text);
}

.page-shell {
  width: min(720px, calc(100% - 28px));
  margin: 18px auto 48px;
}

.header-tabs {
  justify-content: center;
  gap: 6px;
  min-width: 0;
  flex-wrap: wrap;
}

.searchbar {
  width: 100%;
  display: flex;
  justify-content: center;
}

.content,
.feed-list {
  display: grid;
  gap: 14px;
}

.view-nav {
  justify-content: flex-start;
  gap: 8px;
  margin-bottom: 0;
  flex-wrap: wrap;
}

.header-tabs a,
.view-nav a,
.feed-tabs a {
  padding: 7px 12px;
  border-radius: 18px;
  color: var(--muted);
  font-weight: 700;
}

.header-tabs a.active,
.view-nav a.active,
.feed-tabs a.active {
  color: var(--blue);
  background: #e7f0ff;
}

@media (max-width: 1180px) {
  .topbar {
    grid-template-columns: 1fr;
    justify-items: stretch;
  }

  .top-left,
  .top-center,
  .top-actions {
    justify-content: center;
  }

  .top-left {
    flex-wrap: wrap;
  }

  .top-actions {
    justify-content: center;
  }

  .login-strip {
    justify-content: center;
    flex-wrap: wrap;
    width: 100%;
  }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 16px;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.08);
}

.flash-stack {
  display: grid;
  gap: 8px;
  margin-bottom: 14px;
}

.flash {
  padding: 12px 14px;
  border-radius: 8px;
  background: white;
  border: 1px solid var(--line);
  font-weight: 700;
}

.flash.success { color: #137333; }
.flash.error { color: #c5221f; }

.auth-card {
  display: grid;
  gap: 14px;
}

.auth-card h2,
.feed-toolbar h1,
.post-card h2 {
  margin: 0;
}

.auth-form {
  display: grid;
  gap: 10px;
}

.auth-form input {
  padding: 12px 14px;
}

.feed-tabs {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.composer {
  padding: 12px 14px;
}

.simple-composer {
  display: grid;
  gap: 10px;
}

.composer-row {
  align-items: center;
  gap: 10px;
}

textarea {
  width: 100%;
  min-height: 48px;
  resize: vertical;
  padding: 13px 16px;
  border-radius: 24px;
}

.composer-tools {
  gap: 8px;
  flex-wrap: wrap;
  padding-left: 52px;
}

.composer-tools select,
.composer-tools input {
  min-height: 36px;
  padding: 8px 12px;
  border-radius: 18px;
}

.composer-tools input {
  flex: 1 1 140px;
  max-width: 220px;
}

.composer-tools select {
  width: 120px;
}

.composer-tools .primary-btn {
  margin-left: auto;
  min-width: 92px;
  padding: 9px 20px;
}

.feed-toolbar {
  justify-content: space-between;
  gap: 12px;
  padding: 4px 2px;
}

.feed-toolbar h1 {
  font-size: 22px;
}

.feed-toolbar p {
  margin: 6px 0 0;
  max-width: 58ch;
  line-height: 1.5;
}

.feedback-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(260px, 0.8fr);
  gap: 14px;
}

.feedback-panel,
.feedback-form,
.feedback-history {
  display: grid;
  gap: 12px;
}

.feedback-panel h2,
.feedback-history h3 {
  margin: 0;
}

.feedback-form input,
.feedback-form select,
.feedback-form textarea {
  width: 100%;
  padding: 12px 14px;
}

.feedback-form button {
  justify-self: start;
}

.feedback-checklist {
  display: grid;
  gap: 10px;
  color: var(--muted);
  line-height: 1.5;
}

.feedback-history-item {
  display: grid;
  gap: 6px;
  padding: 12px 14px;
  border-radius: 10px;
  background: #f0f2f5;
}

.feedback-history-item p {
  margin: 0;
  line-height: 1.5;
}

.post-card {
  display: grid;
  gap: 12px;
}

.post-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.post-author {
  gap: 10px;
}

.post-kind,
.tag-chip {
  display: inline-flex;
  align-items: center;
  border-radius: 999px;
  white-space: nowrap;
}

.post-kind {
  padding: 6px 10px;
  background: #e7f0ff;
  color: var(--blue);
  font-size: 13px;
  font-weight: 800;
}

.summary {
  margin: 0;
  line-height: 1.5;
  white-space: pre-wrap;
}

.prompt-box {
  margin: 0;
  padding: 14px;
  overflow: auto;
  border-radius: 8px;
  background: #f0f2f5;
  color: #1c1e21;
  font-family: "SFMono-Regular", Menlo, monospace;
  line-height: 1.45;
  white-space: pre-wrap;
}

.tag-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tag-chip {
  padding: 7px 10px;
  background: #f0f2f5;
  color: var(--muted);
  font-size: 13px;
}

.engagement-row {
  gap: 8px;
  flex-wrap: wrap;
  padding-top: 8px;
  border-top: 1px solid var(--line);
}

.ghost-btn {
  padding: 8px 12px;
  background: #f0f2f5;
  color: var(--text);
}

.alt-btn {
  color: var(--blue);
}

.comment-form {
  gap: 8px;
}

.comment-form input {
  flex: 1;
  padding: 10px 12px;
}

.comment-form button {
  padding: 10px 14px;
  background: #e4e6eb;
}

.comment-list {
  display: grid;
  gap: 8px;
}

.comment-item {
  display: grid;
  gap: 3px;
  padding: 10px 12px;
  border-radius: 8px;
  background: #f0f2f5;
}

.profile-hero {
  display: flex;
  gap: 14px;
}

.avatar-orb {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  flex: 0 0 auto;
}

.profile-metrics {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin: 12px 0;
  color: var(--muted);
  font-weight: 700;
}

.profile-follow-btn {
  width: auto;
}

.empty-state {
  text-align: center;
  padding: 44px 20px;
}

.feed-loader {
  display: none;
  padding: 18px;
  color: var(--muted);
  text-align: center;
  font-weight: 700;
}

.feed-loader.visible {
  display: block;
}

@media (max-width: 800px) {
  .topbar {
    grid-template-columns: 1fr;
    justify-items: stretch;
  }

  .top-left {
    flex-wrap: wrap;
  }

  .brand-stack {
    width: 100%;
  }

  .brand {
    justify-content: flex-start;
  }

  .header-tabs {
    justify-content: flex-start;
  }

  .top-actions {
    justify-content: flex-start;
  }

  .searchbar input {
    width: 100%;
  }

  .searchbar input,
  .login-strip input {
    width: 100%;
  }

  .login-strip,
  .top-actions,
  .feed-toolbar,
  .comment-form {
    flex-direction: column;
    align-items: stretch;
  }

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