/* App shell: navigation (tab bar / rail / sidebar), top bar, page frames, search layer. */

.app { min-height: 100vh; min-height: 100dvh; padding-left: var(--nav-w); }
.main { padding-top: var(--topbar-h); padding-bottom: calc(var(--tabbar-h) + var(--s10)); }
body.is-overlay .main { padding-top: 0; }
.page { width: 100%; max-width: calc(var(--content-max) + var(--gutter) * 2); margin-inline: auto; padding-inline: var(--gutter); }

/* ---------- top bar ---------- */
.topbar { position: fixed; z-index: 50; top: 0; left: var(--nav-w); right: 0; height: var(--topbar-h); padding-top: var(--safe-top); pointer-events: none; }
.topbar-bg { position: absolute; inset: 0; background: var(--material); -webkit-backdrop-filter: var(--blur); backdrop-filter: var(--blur); box-shadow: 0 .5px 0 var(--sep); opacity: var(--bar-bg, 0); transition: opacity var(--t-base) var(--ease); }
.topbar.is-scrolled { --bar-bg: 1; }
.topbar[data-chrome="overlay"] .topbar-bg { transition: none; background: color-mix(in srgb, var(--artwork-bg) 78%, transparent); }
.topbar-inner { position: relative; display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; height: 100%; padding-inline: calc(var(--gutter) - 4px); }
.topbar-inner > * { pointer-events: auto; }
.topbar-start { grid-column: 1; display: flex; align-items: center; justify-self: start; }
.topbar-end { grid-column: 3; display: flex; align-items: center; justify-self: end; gap: var(--s2); }
.topbar-title { min-width: 0; pointer-events: none; }
.topbar-title:empty { display: none; }
.topbar[data-chrome="root"] .topbar-inner { padding-inline: var(--gutter); }

.brand { display: inline-flex; align-items: center; gap: 9px; font-family: var(--font-display); font-size: 19px; font-weight: 700; letter-spacing: -.035em; }
.brand-mark { width: 26px; height: 26px; color: var(--accent); }
.brand--bar { min-height: 44px; }

.round-btn { position: relative; display: grid; place-items: center; width: 36px; height: 36px; border-radius: 50%; background: rgb(30 30 34 / .55); color: var(--text); -webkit-backdrop-filter: saturate(1.5) blur(14px); backdrop-filter: saturate(1.5) blur(14px); box-shadow: 0 0 0 .5px rgb(255 255 255 / .12); transition: transform var(--t-fast) var(--ease), background var(--t-fast); }
.round-btn::after { content: ""; position: absolute; inset: -4px; }              /* 44px touch target */
.round-btn:active { transform: scale(.92); }
.round-btn .icon { width: 20px; height: 20px; }
@media (hover: hover) { .round-btn:hover { background: rgb(60 60 66 / .6); } }
@media (prefers-color-scheme: light) { .topbar:not([data-chrome="overlay"]) .round-btn { background: rgb(255 255 255 / .7); box-shadow: 0 0 0 .5px rgb(0 0 0 / .1); } }

/* ---------- tab bar (phones) ---------- */
.tabbar { position: fixed; z-index: 60; left: 0; right: 0; bottom: 0; display: flex; height: var(--tabbar-h); padding-bottom: var(--safe-bottom); background: var(--material); -webkit-backdrop-filter: var(--blur); backdrop-filter: var(--blur); box-shadow: 0 -.5px 0 var(--sep); }
.tabbar > * { flex: 1 1 0; min-width: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px; color: var(--text-3); font-size: 10px; font-weight: 500; letter-spacing: 0; transition: color var(--t-fast); }
.tabbar .icon { width: 25px; height: 25px; transition: transform var(--t-fast) var(--ease); }
.tabbar > *:active .icon { transform: scale(.88); }
.tabbar .is-active { color: var(--accent-text); }

/* ---------- rail / sidebar (tablet landscape and up) ---------- */
.nav-side { display: none; }
@media (min-width: 820px) {
  .tabbar { display: none; }
  .nav-side { position: fixed; z-index: 55; inset: 0 auto 0 0; width: var(--nav-w); display: flex; flex-direction: column; align-items: center; gap: var(--s2); padding: var(--s5) var(--s2); background: var(--surface); box-shadow: .5px 0 0 var(--sep); overflow-y: auto; }
  .brand-word, .side-search span, .side-search kbd, .side-foot p { display: none; }
  .nav-side .brand { margin-bottom: var(--s4); min-height: 44px; }
  .side-search { display: grid; place-items: center; width: 48px; height: 44px; border-radius: var(--r-sm); color: var(--text-2); transition: background var(--t-fast), color var(--t-fast); }
  .side-search:hover { background: var(--fill); color: var(--text); }
  .side-nav { display: grid; gap: 2px; width: 100%; margin-top: var(--s2); }
  .side-nav a, .side-link { position: relative; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px; min-height: 56px; border-radius: var(--r-sm); color: var(--text-2); font-size: 10.5px; font-weight: 500; transition: background var(--t-fast), color var(--t-fast); }
  .side-nav a:hover, .side-link:hover { background: var(--fill); color: var(--text); }
  .side-nav a.is-active, .side-link.is-active { color: var(--accent-text); background: var(--fill); }
  .side-nav small { position: absolute; top: 6px; right: 12px; min-width: 16px; height: 16px; padding: 0 4px; border-radius: 8px; background: var(--accent); color: var(--on-accent); font-size: 10px; font-weight: 600; line-height: 16px; text-align: center; }
  .side-foot { margin-top: auto; width: 100%; display: grid; gap: var(--s2); }
  .topbar[data-chrome="root"] { display: none; }
  body[data-chrome="root"] .main { padding-top: var(--s10); }
}
@media (min-width: 1180px) {
  .nav-side { align-items: stretch; padding: var(--s6) var(--s4) var(--s5); }
  .brand-word { display: inline; }
  .nav-side .brand { padding-inline: var(--s3); margin-bottom: var(--s5); }
  .side-search { display: flex; align-items: center; justify-content: flex-start; gap: var(--s2); width: 100%; height: 38px; padding: 0 var(--s3); background: var(--fill); font-size: 14px; color: var(--text-3); }
  .side-search span { display: inline; }
  .side-search kbd { display: inline; margin-left: auto; padding: 1px 6px; border-radius: 5px; box-shadow: 0 0 0 .5px var(--sep); font: 11px var(--font); color: var(--text-3); }
  .side-nav { margin-top: var(--s5); }
  .side-nav a, .side-link { flex-direction: row; justify-content: flex-start; gap: 12px; min-height: 40px; padding: 0 var(--s3); font-size: 15px; }
  .side-nav a.is-active, .side-link.is-active { background: var(--fill-hover); }
  .side-nav small { position: static; margin-left: auto; }
  .side-foot p { display: block; padding: var(--s2) var(--s3) 0; color: var(--text-3); font-size: 12px; }
}

/* ---------- page header (large title) ---------- */
.page-head { padding-top: var(--s2); padding-bottom: var(--s4); }
.page-head h1 { font-size: 34px; font-weight: 700; letter-spacing: -.035em; line-height: 1.1; }
.page-head p { margin-top: var(--s1); color: var(--text-2); font-size: 15px; }
@media (min-width: 820px) { .page-head { padding-bottom: var(--s6); } .page-head h1 { font-size: 40px; } }

/* ---------- search ---------- */
.search-layer { position: fixed; z-index: 100; inset: 0; }
.search-layer .scrim { position: absolute; inset: 0; background: rgb(0 0 0 / .45); opacity: 0; transition: opacity var(--t-base) var(--ease); }
.search-panel { position: absolute; inset: 0; display: flex; flex-direction: column; background: var(--bg); padding-top: var(--safe-top); opacity: 0; transform: translateY(14px); transition: opacity var(--t-base) var(--ease), transform var(--t-base) var(--ease-out); }
.search-layer.is-open .scrim { opacity: 1; }
.search-layer.is-open .search-panel { opacity: 1; transform: none; }
.search-bar { position: relative; display: flex; align-items: center; gap: var(--s3); padding: var(--s3) var(--gutter); }
.search-bar > .icon { position: absolute; left: calc(var(--gutter) + 12px); width: 18px; height: 18px; color: var(--text-3); pointer-events: none; }
.search-bar input { flex: 1; min-width: 0; height: 40px; padding: 0 var(--s3) 0 40px; border: 0; border-radius: 12px; background: var(--fill); color: var(--text); font-size: 17px; outline: none; -webkit-appearance: none; appearance: none; }
.search-bar input::placeholder { color: var(--text-3); }
.search-bar input::-webkit-search-cancel-button { display: none; }
.search-bar input:focus-visible { box-shadow: 0 0 0 2px color-mix(in srgb, var(--accent) 70%, transparent); }
.text-btn { min-height: 44px; padding: 0 var(--s1); color: var(--accent-text); font-size: 16px; }
.search-results { flex: 1; overflow-y: auto; overscroll-behavior: contain; padding: var(--s2) 0 calc(var(--s6) + var(--safe-bottom)); }
@media (min-width: 820px) {
  .search-panel { inset: 11vh auto auto 50%; width: min(680px, calc(100vw - 48px)); max-height: 72vh; margin-left: calc(min(680px, 100vw - 48px) / -2); padding-top: 0; border-radius: var(--r-lg); background: var(--surface); box-shadow: var(--shadow-pop); transform: translateY(-8px) scale(.985); }
  .search-bar { padding: var(--s4) var(--s4) var(--s3); box-shadow: 0 .5px 0 var(--sep); }
  .search-bar > .icon { left: calc(var(--s4) + 12px); }
  .search-bar input { background: transparent; font-size: 18px; }
  .search-bar input:focus-visible { box-shadow: none; }
  .text-btn { display: none; }
}