/* ============================================================
   Nexus — iOS-style grouped list + channel info
   Metrics derived from Telegram-iOS research:
   inset 16 · row ~44 · section header 13 · section gap 24
   ============================================================ */

:root {
  --ui-inset: 16px;
  --ui-row-h: 44px;
  --ui-section-gap: 24px;
  --ui-icon: 29px;
  --ui-icon-r: 50%;
  --ui-fs-title: 1rem;      /* ~17pt */
  --ui-fs-value: .9rem;     /* ~15pt */
  --ui-fs-section: .8rem;   /* ~13pt */
  --ui-switch-w: 51px;
  --ui-switch-h: 31px;
  --ui-switch-k: 27px;
}

/* ---------- section header / spacer ---------- */
.ui-section { font-size: var(--ui-fs-section); color: var(--nb-text-mute); padding: var(--ui-section-gap) var(--ui-inset) 7px; }
.ui-gap { height: var(--ui-section-gap); }
.app-top-link { color: inherit; text-decoration: none; }

/* ---------- grouped card ---------- */
.ui-list { background: var(--nb-surface); border-radius: var(--r-card); overflow: hidden; margin-bottom: var(--ui-section-gap); }

/* ---------- row ---------- */
.ui-row {
  position: relative; display: flex; align-items: center; gap: 12px;
  min-height: var(--ui-row-h); padding: 8px var(--ui-inset);
  width: 100%; border: 0; font: inherit; text-align: start; cursor: pointer;
  color: var(--nb-text); background: var(--nb-surface); text-decoration: none;
  transition: background .12s ease;
}
.ui-row:active { background: var(--nb-surface-hi); }
.ui-row:not(:last-child)::after {
  content: ''; position: absolute; bottom: 0; inset-inline: 0; height: 1px;
  background: var(--nb-line);
}
.ui-row.has-icon:not(:last-child)::after { inset-inline-start: calc(var(--ui-inset) + var(--ui-icon) + 12px); }

.ui-row-icon { flex: none; width: var(--ui-icon); height: var(--ui-icon); border-radius: var(--ui-icon-r); display: grid; place-items: center; background: var(--nb-surface-hi); color: var(--brand); }
.ui-row-icon.ico-blue { background: rgba(0, 122, 255, .14); color: #007aff; }
.ui-row-icon.ico-green { background: rgba(52, 199, 89, .16); color: #34c759; }
.ui-row-icon.ico-purple { background: rgba(175, 82, 222, .15); color: #af52de; }
.ui-row-icon.ico-gold { background: rgba(255, 149, 0, .15); color: #ff9500; }
.ui-row-icon.ico-red { background: rgba(255, 59, 48, .14); color: #ff3b30; }

.ui-row-main { flex: 1; min-width: 0; display: flex; flex-direction: column; gap: 1px; }
.ui-row-title { font-size: var(--ui-fs-title); line-height: 1.4; }
.ui-row-value { font-size: var(--ui-fs-value); color: var(--nb-text-mute); line-height: 1.4; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.ui-row.is-multiline .ui-row-value { white-space: normal; }
.ui-row-chevron { flex: none; color: var(--nb-text-mute); display: inline-flex; }
.ui-row.is-destructive .ui-row-title { color: var(--err); }
.ui-row.is-destructive .ui-row-icon { background: var(--err-bg); color: var(--err); }

/* ---------- iOS switch ---------- */
.ui-switch { flex: none; position: relative; width: var(--ui-switch-w); height: var(--ui-switch-h); border-radius: var(--r-pill); background: #e9e9ea; transition: background .2s ease; }
.ui-switch > span { position: absolute; top: 2px; inset-inline-start: 2px; width: var(--ui-switch-k); height: var(--ui-switch-k); border-radius: 50%; background: #fff; box-shadow: 0 2px 4px rgba(0, 0, 0, .2); transition: transform .2s var(--ch-ease); }
.ui-switch.is-on { background: #34c759; }
.ui-switch.is-on > span { transform: translateX(-20px); }
[data-theme="dark"] .ui-switch { background: #39393d; }

/* ============================================================
   Channel info page
   ============================================================ */
.ci-page { max-width: 640px; margin-inline: auto; padding: 0 16px 24px; }
.ci-head { text-align: center; padding: 20px 12px 14px; }
.ci-avatar { width: 92px; height: 92px; border-radius: 50%; margin: 0 auto 12px; display: grid; place-items: center; object-fit: cover; background: var(--grad); color: #fff; font-size: 2.2rem; font-weight: 900; box-shadow: 0 12px 30px -12px rgba(30, 120, 210, .55); }
.ci-name { font-size: 1.4rem; font-weight: 800; line-height: 1.5; }
.ci-sub { color: var(--nb-text-mute); font-size: .9rem; }

.ci-actions { display: flex; gap: 6px; padding: 4px 0 10px; }
.ci-action { flex: 1; display: flex; flex-direction: column; align-items: center; gap: 5px; padding: 10px 4px; border: 0; border-radius: var(--r-control); background: var(--nb-surface); color: var(--brand); font: inherit; font-size: .72rem; font-weight: 600; cursor: pointer; text-decoration: none; transition: background .15s ease; }
.ci-action:active { background: var(--nb-surface-hi); }
.ci-action .ch-i { color: var(--brand); }

.ci-tabs { display: flex; gap: 4px; background: var(--nb-surface-hi); border-radius: var(--r-control); padding: 4px; margin-bottom: 12px; }
.ci-tab { flex: 1; text-align: center; padding: 7px 6px; border-radius: var(--r-inner); font-size: .84rem; font-weight: 600; color: var(--nb-text-mute); text-decoration: none; transition: background .15s ease, color .15s ease; }
.ci-tab.is-active { background: var(--nb-surface); color: var(--nb-text); box-shadow: 0 1px 2px rgba(0, 0, 0, .06); }

.ci-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 4px; }
.ci-cell { position: relative; aspect-ratio: 1 / 1; border-radius: calc(var(--r-card) - 4px); overflow: hidden; background: var(--nb-surface-hi); }
.ci-cell img { width: 100%; height: 100%; object-fit: cover; }
.ci-cell-text { display: grid; place-items: center; padding: 8px; font-size: .72rem; color: var(--nb-text-mute); text-align: center; }

/* ---------- channel settings form ---------- */
.ci-form { padding: 0; }
.ci-form .form-row { padding: 0 14px; margin: 12px 0; }
.ci-form .form-row:first-child { margin-top: 14px; }
.ci-form .form-row:last-child { margin-bottom: 14px; }
.ci-form .btn { margin: 0 14px 14px; }
.ci-photo { display: flex; align-items: center; gap: 14px; padding: 14px; }
.ci-photo-img { width: 64px; height: 64px; border-radius: 50%; object-fit: cover; background: var(--grad); color: #fff; display: grid; place-items: center; font-size: 1.5rem; font-weight: 900; flex: none; }