/* ==========================================================================
   通天路 · 圈子广场 /circles（2026-09-18 波次）
   仅 circles.html {% block extra_head %} 引用（晚于 vendor_head，可覆盖同特异性规则）。
   约束（docs/frontend-architecture.md §3.5 · shadcn 边框口径）：
   - 颜色全部走主题变量（--card/--border/--muted/--ring/--brand-*）
   - 卡片 = 1px var(--border) + var(--card) + 中性 shadow；hover 走背景/阴影，无彩色边框
   - 间距走 Tailwind spacing scale 等价 rem；圆角 0.75 / 1 / 1.25 / 1.5rem
   - 零外链图片 / 字体 / CDN；动效 160–180ms；尊重 prefers-reduced-motion
   - 触达 ≥44px；320–1920 无横滚（min-width:0 + overflow-wrap）
   ========================================================================== */

/* ---- 封面 / hero 主题 token（亮色） ------------------------------------ */
:root {
  --circles-cover-a: color-mix(in srgb, var(--brand-gold-soft) 58%, var(--card));
  --circles-cover-b: color-mix(in srgb, var(--brand-blue) 22%, var(--card));
  --circles-cover-glow: color-mix(in srgb, var(--brand-gold) 36%, transparent);
  --circles-hero-sky: color-mix(in srgb, var(--brand-gold-soft) 54%, var(--card));
  --circles-hero-low: color-mix(in srgb, var(--brand-blue) 14%, var(--card));
}

html.dark,
[data-theme="dark"],
:root.dark {
  --circles-cover-a: color-mix(in srgb, var(--brand-gold-soft) 46%, var(--background));
  --circles-cover-b: color-mix(in srgb, var(--brand-blue) 30%, var(--background));
  --circles-cover-glow: color-mix(in srgb, var(--brand-gold) 26%, transparent);
  --circles-hero-sky: color-mix(in srgb, var(--brand-gold-soft) 38%, var(--background));
  --circles-hero-low: color-mix(in srgb, var(--brand-blue) 26%, var(--background));
}

/* ---- 页面纵向节奏 -------------------------------------------------------- */
.circles-page {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  min-width: 0;
}

@media (min-width: 640px) {
  .circles-page {
    gap: 1.5rem;
  }
}

/* ==========================================================================
   1. 页头（标题 + 一句话说明 + 总数 / 游客登录 CTA）
   ========================================================================== */
.circles-hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  min-width: 0;
  padding: 1.25rem;
  border-radius: 1.25rem;
  border: 1px solid var(--border);
  background:
    radial-gradient(120% 150% at 88% -18%, var(--circles-cover-glow) 0%, transparent 56%),
    linear-gradient(135deg, var(--circles-hero-sky) 0%, var(--card) 58%, var(--circles-hero-low) 100%);
}

@media (min-width: 640px) {
  .circles-hero {
    flex-direction: row;
    align-items: flex-end;
    justify-content: space-between;
    gap: 1.5rem;
    padding: 1.75rem 2rem;
    border-radius: 1.5rem;
  }
}

.circles-hero__copy {
  position: relative;
  z-index: 1;
  min-width: 0;
}

.circles-hero__title {
  margin: 0;
  font-size: clamp(1.5rem, 3vw, 2.125rem);
  line-height: 1.25;
  font-weight: 700;
  color: var(--foreground);
  overflow-wrap: anywhere;
}

.circles-hero__tagline {
  margin: 0.375rem 0 0;
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--muted-foreground);
  overflow-wrap: anywhere;
}

@media (min-width: 768px) {
  .circles-hero__tagline {
    font-size: 1rem;
  }
}

.circles-hero__meta {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 0.75rem;
  margin: 0;
  min-width: 0;
}

.circles-hero__count {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  min-height: 2.25rem;
  padding-inline: 0.875rem;
  border-radius: 9999px;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--foreground);
  font-size: 0.8125rem;
  font-weight: 600;
  white-space: nowrap;
}

.circles-hero__count-icon {
  color: var(--brand-gold-strong);
}

.circles-hero__login {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  min-height: 2.75rem;
  padding-inline: 1.1rem;
  border-radius: 9999px;
  background: var(--primary);
  color: var(--primary-foreground);
  font-size: 0.8125rem;
  font-weight: 600;
  white-space: nowrap;
  text-decoration: none;
  transition: background-color 160ms ease;
}

.circles-hero__login:hover {
  background: color-mix(in srgb, var(--primary) 90%, transparent);
}

.circles-hero__login:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
}

/* 山影装饰（品牌 hero 语言；纯 CSS/SVG，无外链） */
.circles-hero__art {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 0;
  width: 100%;
  height: 3.5rem;
  opacity: 0.3;
  pointer-events: none;
}

.circles-hero__ridge--far {
  fill: color-mix(in srgb, var(--brand-blue) 30%, transparent);
}

.circles-hero__ridge--near {
  fill: color-mix(in srgb, var(--foreground) 16%, transparent);
}

/* ==========================================================================
   2. 我加入的圈子（登录 + 非空）
   ========================================================================== */
.circles-section-title {
  margin: 0 0 0.75rem;
  font-size: 1.125rem;
  line-height: 1.4;
  font-weight: 650;
  color: var(--foreground);
  overflow-wrap: anywhere;
}

.circles-joined__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.625rem;
  min-width: 0;
}

@media (min-width: 640px) {
  .circles-joined__list {
    grid-template-columns: repeat(auto-fill, minmax(11rem, 1fr));
  }
}

.circles-joined__item {
  min-width: 0;
}

.circles-joined__link {
  display: flex;
  align-items: center;
  gap: 0.625rem;
  min-width: 0;
  min-height: 3.25rem;
  padding: 0.5rem 0.75rem;
  border-radius: 0.75rem;
  border: 1px solid var(--border);
  background: var(--card);
  text-decoration: none;
  transition: background-color 160ms ease;
}

.circles-joined__link:hover {
  background: color-mix(in srgb, var(--muted) 42%, var(--card));
}

.circles-joined__link:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
}

.circles-joined__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  width: 2rem;
  height: 2rem;
  border-radius: 50%;
  overflow: hidden;
  background: var(--muted);
  color: var(--brand-gold-strong);
  font-size: 0.8125rem;
  font-weight: 700;
  line-height: 1;
}

.circles-joined__icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.circles-joined__copy {
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  min-width: 0;
}

.circles-joined__name {
  font-size: 0.8125rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--foreground);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.circles-joined__meta {
  font-size: 0.6875rem;
  line-height: 1.5;
  color: var(--muted-foreground);
  font-variant-numeric: tabular-nums;
}

.circles-joined__check {
  flex: none;
  color: var(--brand-gold-strong);
}

/* ==========================================================================
   3. 分组 + 圈子卡片网格（1 / 2 / 3 / 4 列）
   ========================================================================== */
.circles-groups {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  min-width: 0;
}

@media (min-width: 640px) {
  .circles-groups {
    gap: 2rem;
  }
}

.circles-group {
  min-width: 0;
}

.circles-group__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.375rem 0.75rem;
  margin-bottom: 0.75rem;
  min-width: 0;
}

.circles-group__title {
  margin: 0;
  font-size: 1.125rem;
  line-height: 1.4;
  font-weight: 650;
  color: var(--foreground);
  overflow-wrap: anywhere;
}

.circles-group__desc {
  margin: 0;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--muted-foreground);
  overflow-wrap: anywhere;
}

.circles-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 0.75rem;
  min-width: 0;
}

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

@media (min-width: 1024px) {
  .circles-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }
}

@media (min-width: 1280px) {
  .circles-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

/* ---- 卡片 ---------------------------------------------------------------- */
.circle-card {
  display: flex;
  flex-direction: column;
  min-width: 0;
  overflow: hidden;
  border-radius: 1rem;
  border: 1px solid var(--border);
  background: var(--card);
  box-shadow: 0 1px 2px rgb(42 33 24 / 0.06);
  transition: background-color 180ms ease, box-shadow 180ms ease;
}

.circle-card:hover {
  background: color-mix(in srgb, var(--muted) 26%, var(--card));
  box-shadow: 0 10px 28px -22px rgb(42 33 24 / 0.55);
}

.circle-card__cover {
  position: relative;
  display: block;
  height: 5.5rem;
  overflow: hidden;
  background: linear-gradient(120deg, var(--circles-cover-a) 0%, var(--circles-cover-b) 100%);
}

.circle-card__cover-img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  max-width: none;
  object-fit: cover;
  object-position: center 45%;
}

.circle-card__cover-glow {
  position: absolute;
  right: 10%;
  top: -40%;
  width: 6rem;
  aspect-ratio: 1;
  border-radius: 50%;
  background: radial-gradient(circle, var(--circles-cover-glow) 0%, transparent 68%);
  filter: blur(2px);
  pointer-events: none;
}

.circle-card__cover:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: -2px;
}

.circle-card__body {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  flex: 1 1 auto;
  gap: 0.5rem;
  min-width: 0;
  margin-top: -1.375rem;
  padding: 0 1rem 1rem;
}

.circle-card__icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: none;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  /* shadcn avatar ring-background 等价：card 色挖孔环（fix-borders-shadcn §4.2 保留项） */
  border: 3px solid var(--card);
  overflow: hidden;
  background: var(--muted);
  color: var(--brand-gold-strong);
  box-shadow: 0 1px 2px rgb(42 33 24 / 0.08);
}

.circle-card__icon-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.circle-card__initial {
  font-size: 1rem;
  font-weight: 700;
  line-height: 1;
}

.circle-card__name {
  margin: 0;
  min-width: 0;
  font-size: 1rem;
  line-height: 1.4;
  font-weight: 650;
}

.circle-card__link {
  color: var(--foreground);
  text-decoration: none;
  overflow-wrap: anywhere;
}

.circle-card__link:hover {
  text-decoration: underline;
  text-underline-offset: 3px;
}

.circle-card__link:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
  border-radius: 0.25rem;
}

.circle-card__desc {
  margin: 0;
  min-width: 0;
  font-size: 0.8125rem;
  line-height: 1.6;
  color: var(--muted-foreground);
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 2;
  overflow: hidden;
  overflow-wrap: anywhere;
}

.circle-card__meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 0.375rem;
  margin: 0;
  font-size: 0.75rem;
  line-height: 1.5;
  color: var(--muted-foreground);
}

.circle-card__dot {
  color: color-mix(in srgb, var(--muted-foreground) 55%, transparent);
}

.circle-card__action {
  margin-top: auto;
  padding-top: 0.25rem;
}

.circle-card__form {
  margin: 0;
}

.circle-card__join {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.375rem;
  width: 100%;
  min-height: 2.75rem;
  padding-inline: 0.875rem;
  border-radius: 0.75rem;
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--foreground);
  font-size: 0.8125rem;
  font-weight: 600;
  white-space: nowrap;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 160ms ease, border-color 160ms ease;
}

.circle-card__join:hover {
  background: var(--muted);
  border-color: var(--border);
}

.circle-card__join.is-member {
  background: var(--muted);
  color: var(--muted-foreground);
}

.circle-card__join:focus-visible {
  outline: 2px solid var(--ring);
  outline-offset: 2px;
}

/* ==========================================================================
   4. 空态（宏 ui::empty_state 承担视觉，此处只保证间距）
   ========================================================================== */
.circles-empty {
  min-width: 0;
}

/* ==========================================================================
   5. 动效 · prefers-reduced-motion
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  .circle-card,
  .circle-card__join,
  .circles-joined__link,
  .circles-hero__login {
    transition: none !important;
    transform: none !important;
    animation: none !important;
  }
}