/* ────────────────────────────────────────────────────────────────
   Tom — Shell Components
   The persistent chrome that wraps every screen: header (two
   variants), bottom tab bar, and right-edge chat trigger + panel.

   Pairs with tom-tokens.css. Per-screen styles live in their own
   file or inline <style> — they consume tokens here, never override
   shell layout.
   ──────────────────────────────────────────────────────────────── */

/* ── App container ─────────────────────────────────────────────── */
.app {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  width: 100%;
  position: relative;
  background: var(--surface);
}

/* ════════════════════════════════════════════════════════════════
   HEADER — two variants
   ────────────────────────────────────────────────────────────────
   .shell-header              base 56px row, flex
     .shell-header--landing   brand-mark + wordmark + spacer + right slot
     .shell-header--sub       back-chev + centred identity + right slot

   Right slot is always the .xp-pill on every screen — gamification
   visible everywhere.
   ════════════════════════════════════════════════════════════════ */

.shell-header {
  flex-shrink: 0;
  height: var(--header-h);
  background: var(--surface);
  padding: 0 16px;
  display: flex;
  align-items: center;
  gap: 10px;
  z-index: 30;
  position: relative;
}

/* Sub-screen header uses a 1fr auto 1fr grid so the centre cluster sits
   at true viewport centre regardless of the back-chev / right-slot
   width difference. Flex-based centring fails when left and right
   children have different widths — the leftover space is asymmetric. */
.shell-header--sub {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
}
.shell-header--sub > .back-chev { justify-self: start; }
.shell-header--sub > .xp-pill   { justify-self: end; }

/* Brand mark — the T disc. Present on landing headers only. */
.brand-mark {
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 15px;
  font-weight: 800;
  letter-spacing: -0.5px;
  box-shadow: 0 0 0 3px var(--surface), 0 0 0 4px var(--hairline);
  flex-shrink: 0;
}

.wordmark {
  font-size: 20px;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.01em;
}

/* Back chevron — present on sub-screen headers, replaces brand+wordmark */
.back-chev {
  width: 36px; height: 36px;
  border: 0;
  background: transparent;
  border-radius: 999px;
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--ink);
  cursor: pointer;
  flex-shrink: 0;
  margin-left: -6px;
}
.back-chev:hover { background: rgba(0,0,0,0.04); }
.back-chev svg { width: 16px; height: 16px; }

/* Centred screen identity on sub-screens. Either text (.screen-title) or
   an interactive control (.kmode-pill etc — defined in per-screen CSS). */
.screen-identity {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-width: 0;
}
.screen-title {
  font-size: 16px;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.spacer { flex: 1; }

/* ── XP / Lv pill — canonical right slot ─────────────────────────
   Lifted from skills-screen-v2. Used identically on every screen. */
.xp-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px 5px 10px;
  background: var(--surface);
  border: 1px solid var(--tab-border);
  border-radius: 999px;
  box-shadow: var(--sh-tab);
  font-size: 12px;
  font-weight: 800;
  color: var(--gold-text);
  font-feature-settings: "tnum" 1;
  cursor: pointer;
  flex-shrink: 0;
}
.xp-pill:hover { filter: brightness(0.98); }
.xp-bolt {
  width: 11px; height: 11px;
  background: var(--gold);
  clip-path: polygon(55% 0, 0 60%, 40% 60%, 25% 100%, 100% 35%, 55% 35%);
  display: inline-block;
}
.xp-pill .lvl {
  color: var(--ink-2);
  font-weight: 700;
  border-left: 1px solid var(--hairline);
  padding-left: 8px;
}

/* ════════════════════════════════════════════════════════════════
   BOTTOM TAB BAR
   ────────────────────────────────────────────────────────────────
   Floating pill, label-only, four destinations. Spec from Tom
   Design System v1.1 §12. Pages must allow var(--nav-reserve) at
   the bottom of their main content for clearance.
   ════════════════════════════════════════════════════════════════ */

.tabbar {
  position: fixed;
  left: 50%;
  transform: translateX(-50%);
  bottom: 16px;
  width: calc(100% - 32px);
  max-width: 420px;
  background: var(--surface);
  border: 1px solid var(--tab-border);
  border-radius: 999px;
  padding: 4px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2px;
  z-index: 20;
  box-shadow: var(--sh-pop);
}
.tabbar .tab {
  appearance: none;
  background: var(--surface);
  border: 0;
  color: var(--ink-2);
  font-weight: 700;
  font-size: 12px;
  padding: 10px 6px;
  border-radius: 999px;
  cursor: pointer;
  line-height: 1;
  text-align: center;
  white-space: nowrap;
}
.tabbar .tab[aria-current="page"] {
  background: var(--ink);
  color: #fff;
}

@media (min-width: 768px) {
  .tabbar { max-width: 343px; }
}

/* ════════════════════════════════════════════════════════════════
   CHAT TRIGGER + PANEL
   ────────────────────────────────────────────────────────────────
   Right-edge floating disc (Copilot-style). Tap → panel slides in
   from right. On mobile: panel becomes a full-width bottom sheet.

   The trigger is built around the brand "T" disc (placeholder for
   Tom's eventual face) with a small speech-bubble notch indicator.
   Pulses once per session via .chat-trigger.is-pulsing — JS sets
   the class on first load and removes it after one cycle.
   ════════════════════════════════════════════════════════════════ */

/* ── Mood-ring system (2026-05-10) ────────────────────────────
   Two CSS variables — --tom-avatar-image and --tom-mood-ring —
   are set on body via [data-tom-state="X"]. They cascade into
   the chat trigger and the chat-panel placeholder mark, swapping
   both the avatar image AND the ring colour together. The ring
   uses note-palette tokens (--note-X) to encode mood: warm hues
   for celebration, cool for listening, purple for thinking, etc.
   The face still does its work, but the ring carries the state
   at any size — particularly important at 44px trigger size and
   for distance / glance readability. */
body[data-tom-state="neutral"] {
  --tom-avatar-image: url("assets/Tom_Avatar.png");
  --tom-mood-ring: var(--hairline);
}
body[data-tom-state="listening"] {
  --tom-avatar-image: url("assets/Tom_Listening.png");
  --tom-mood-ring: var(--note-Fs);
}
body[data-tom-state="encouraging"] {
  --tom-avatar-image: url("assets/Tom_Encouraging.png");
  --tom-mood-ring: var(--note-C);  /* orange — was celebration's colour; --note-A yellow-green was too close to gold */
}
body[data-tom-state="celebration"] {
  --tom-avatar-image: url("assets/Tom_Celebration.png");
  --tom-mood-ring: var(--gold);    /* gold ties to the existing live/completion semantic */
}
body[data-tom-state="thinking"] {
  --tom-avatar-image: url("assets/Tom_Thinking_Processing.png");
  --tom-mood-ring: var(--note-Eb);
}

/* Mood pulse — two intensities.
   Soft pulse runs ambiently on every state to give Tom a quiet
   "alive" cue — the ring breathes by 1px every 4 seconds. Loud
   pulse runs on thinking + celebration to make those states
   visibly active rather than static moods (Tom is processing,
   Tom is celebrating — both deserve attention). Reduced-motion
   suppresses both. */
@keyframes tom-mood-pulse-soft {
  0%, 100% {
    box-shadow:
      0 8px 20px rgba(0, 0, 0, 0.16),
      0 2px 6px  rgba(0, 0, 0, 0.08),
      0 0 0 3px  var(--surface),
      0 0 0 5px  var(--tom-mood-ring);
  }
  50% {
    box-shadow:
      0 8px 20px rgba(0, 0, 0, 0.16),
      0 2px 6px  rgba(0, 0, 0, 0.08),
      0 0 0 3px  var(--surface),
      0 0 0 6px  var(--tom-mood-ring);
  }
}
@keyframes tom-mood-pulse-soft-flat {
  0%, 100% {
    box-shadow:
      0 0 0 3px var(--surface),
      0 0 0 6px var(--tom-mood-ring);
  }
  50% {
    box-shadow:
      0 0 0 3px var(--surface),
      0 0 0 7px var(--tom-mood-ring);
  }
}
@keyframes tom-thinking-pulse {
  0%, 100% {
    box-shadow:
      0 8px 20px rgba(0, 0, 0, 0.16),
      0 2px 6px  rgba(0, 0, 0, 0.08),
      0 0 0 3px  var(--surface),
      0 0 0 5px  var(--tom-mood-ring);
  }
  50% {
    box-shadow:
      0 8px 20px rgba(0, 0, 0, 0.16),
      0 2px 6px  rgba(0, 0, 0, 0.08),
      0 0 0 3px  var(--surface),
      0 0 0 9px  var(--tom-mood-ring);
  }
}
@keyframes tom-thinking-pulse-flat {
  0%, 100% {
    box-shadow:
      0 0 0 3px var(--surface),
      0 0 0 6px var(--tom-mood-ring);
  }
  50% {
    box-shadow:
      0 0 0 3px var(--surface),
      0 0 0 10px var(--tom-mood-ring);
  }
}

.chat-trigger {
  position: fixed;
  right: var(--chat-trigger-right);
  top: var(--chat-trigger-top);
  width: var(--chat-trigger-size);
  height: var(--chat-trigger-size);
  border: 0;
  border-radius: 50%;
  background: var(--ink) var(--tom-avatar-image, url("assets/Tom_Avatar.png")) center / cover no-repeat;
  color: transparent;
  font-family: var(--font-sans);
  font-size: 0;
  font-weight: 800;
  letter-spacing: -0.5px;
  cursor: pointer;
  z-index: 50;
  /* Layered elevation — drop + halo + mood-ring (note-coloured per state) */
  box-shadow:
    0 8px 20px rgba(0, 0, 0, 0.16),
    0 2px 6px  rgba(0, 0, 0, 0.08),
    0 0 0 3px  var(--surface),
    0 0 0 5px  var(--tom-mood-ring, var(--hairline));
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform var(--t-state) var(--ease-out), box-shadow var(--t-state) var(--ease-out);
  animation: tom-mood-pulse-soft 4000ms ease-in-out infinite;
}
/* Loud pulse overrides the soft default on thinking + celebration */
body[data-tom-state="thinking"] .chat-trigger,
body[data-tom-state="celebration"] .chat-trigger {
  animation: tom-thinking-pulse 2400ms ease-in-out infinite;
}
@media (prefers-reduced-motion: reduce) {
  .chat-trigger,
  body[data-tom-state="thinking"] .chat-trigger,
  body[data-tom-state="celebration"] .chat-trigger { animation: none; }
}
.chat-trigger:hover { transform: translateY(-1px); }
.chat-trigger:active { transform: translateY(0); }

/* Speech-bubble notch — sits at the disc's bottom-left corner so it
   reads as "this is a chat bubble that contains Tom". */
.chat-trigger::after {
  content: "";
  position: absolute;
  width: 14px; height: 14px;
  background: var(--ink);
  bottom: -2px;
  left: -2px;
  clip-path: polygon(0 0, 100% 100%, 0 100%);
  border-radius: 0 0 0 4px;
}

/* Pulse-once animation. JS class .is-pulsing → animation runs → JS
   removes class after animation ends. The animation itself is
   independent of state; only its application is gated. */
@keyframes chat-pulse {
  0%   { box-shadow: var(--sh-pop), 0 0 0 3px var(--surface), 0 0 0 4px var(--hairline), 0 0 0 4px rgba(26,26,26,0.4); }
  60%  { box-shadow: var(--sh-pop), 0 0 0 3px var(--surface), 0 0 0 4px var(--hairline), 0 0 0 18px rgba(26,26,26,0); }
  100% { box-shadow: var(--sh-pop), 0 0 0 3px var(--surface), 0 0 0 4px var(--hairline), 0 0 0 18px rgba(26,26,26,0); }
}
.chat-trigger.is-pulsing { animation: chat-pulse 1800ms var(--ease-out-cubic) 1 both; }
@media (prefers-reduced-motion: reduce) {
  .chat-trigger.is-pulsing { animation: none; }
}

/* ── Chat panel ──────────────────────────────────────────────── */
.chat-scrim {
  position: fixed; inset: 0;
  background: rgba(26,26,26,0.18);
  z-index: 60;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--t-drawer) var(--ease-out);
}
.chat-scrim.is-open {
  opacity: 1;
  pointer-events: auto;
}

.chat-panel {
  position: fixed;
  top: 0; right: 0; bottom: 0;
  width: var(--chat-panel-w);
  background: var(--surface);
  z-index: 70;
  transform: translateX(100%);
  transition: transform var(--t-drawer) var(--ease-out-cubic);
  display: flex;
  flex-direction: column;
  /* Lateral shadow — projects leftward into the canvas so the
     panel reads as floating above content, not flush to the edge */
  box-shadow:
    -16px 0 40px rgba(0, 0, 0, 0.14),
    -4px  0 12px rgba(0, 0, 0, 0.06);
}
.chat-panel.is-open { transform: translateX(0); }

.chat-panel__head {
  flex: 0 0 auto;
  height: var(--header-h);
  border-bottom: 1px solid var(--hairline);
  display: flex;
  align-items: center;
  padding: 0 16px;
  gap: 12px;
}
.chat-panel__title {
  font-size: 16px;
  font-weight: 800;
  color: var(--ink);
  flex: 1;
}
.chat-panel__close {
  width: 32px; height: 32px;
  border: 0;
  background: transparent;
  border-radius: 999px;
  cursor: pointer;
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--ink-2);
}
.chat-panel__close:hover { background: rgba(0,0,0,0.04); color: var(--ink); }
.chat-panel__close svg { width: 14px; height: 14px; }

.chat-panel__body {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 32px 20px 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  gap: 16px;
  text-align: center;
  color: var(--ink-2);
}
.chat-panel__placeholder-mark {
  width: 144px; height: 144px;
  border-radius: 50%;
  background: var(--ink) var(--tom-avatar-image, url("assets/Tom_Avatar.png")) center / cover no-repeat;
  color: transparent;
  display: flex; align-items: center; justify-content: center;
  font-size: 0; font-weight: 800; letter-spacing: -0.5px;
  margin-bottom: 8px;
  box-shadow: 0 0 0 3px var(--surface), 0 0 0 6px var(--tom-mood-ring, var(--hairline));
  animation: tom-mood-pulse-soft-flat 4000ms ease-in-out infinite;
}
body[data-tom-state="thinking"] .chat-panel__placeholder-mark,
body[data-tom-state="celebration"] .chat-panel__placeholder-mark {
  animation: tom-thinking-pulse-flat 2400ms ease-in-out infinite;
}
@media (prefers-reduced-motion: reduce) {
  .chat-panel__placeholder-mark,
  body[data-tom-state="thinking"] .chat-panel__placeholder-mark,
  body[data-tom-state="celebration"] .chat-panel__placeholder-mark { animation: none; }
}
.chat-panel__placeholder-title {
  font-size: 16px;
  font-weight: 800;
  color: var(--ink);
}
.chat-panel__placeholder-body {
  font-size: 13px;
  font-weight: 500;
  max-width: 28ch;
  line-height: 1.5;
}

.chat-panel__compose {
  flex: 0 0 auto;
  border-top: 1px solid var(--hairline);
  padding: 12px 16px 16px;
  display: flex;
  gap: 8px;
}
.chat-panel__compose input {
  flex: 1;
  height: 40px;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0 16px;
  font-size: 13px;
  background: var(--page-bg);
  color: var(--ink);
}
.chat-panel__compose input::placeholder { color: var(--label-soft); }
.chat-panel__compose input:disabled { cursor: not-allowed; }

/* ── Mobile fallback — chat becomes a bottom sheet ──────────── */
@media (max-width: 599px) {
  .chat-panel {
    top: auto;
    width: 100%;
    height: 80dvh;
    border-radius: 16px 16px 0 0;
    transform: translateY(100%);
    /* Bottom sheet — shadow projects upward off the top edge */
    box-shadow:
      0 -16px 40px rgba(0, 0, 0, 0.14),
      0 -4px  12px rgba(0, 0, 0, 0.06);
  }
  .chat-panel.is-open { transform: translateY(0); }
  .chat-panel__head::before {
    content: "";
    position: absolute;
    top: 8px; left: 50%;
    transform: translateX(-50%);
    width: 36px; height: 4px;
    border-radius: 2px;
    background: var(--border);
  }
  .chat-panel__head { position: relative; padding-top: 16px; }
}

@media (prefers-reduced-motion: reduce) {
  .chat-scrim, .chat-panel { transition: none; }
}