/* ==========================================================================
   Poseidon Canonical Button System
   --------------------------------------------------------------------------
   Single source of truth for buttons across every Poseidon dashboard.
   Theme: teal #14b8a6 accent. Drop-in classes — no build step.

   Usage:
     <button class="btn btn-primary">Save</button>
     <button class="btn btn-ghost btn-sm">Cancel</button>
     <a class="btn btn-danger btn-lg" href="...">Delete</a>

   Variants : .btn-primary  .btn-secondary  .btn-ghost  .btn-danger
   Sizes    : .btn-sm (32px)  .btn-md (40px, default)  .btn-lg (48px)
   ========================================================================== */

:root {
  --pb-teal:        #14b8a6; /* teal-500  — base accent            */
  --pb-teal-hover:  #0d9488; /* teal-600  — hover                  */
  --pb-teal-active: #0f766e; /* teal-700  — active / pressed       */
  --pb-teal-ring:   #2dd4bf; /* teal-400  — focus ring (at 50%)    */
  --pb-zinc-800:    #27272a; /* secondary fill                     */
  --pb-zinc-700:    #3f3f46; /* secondary hover                    */
  --pb-red-600:     #dc2626; /* danger fill                        */
  --pb-red-700:     #b91c1c; /* danger hover                       */
  --pb-radius:      8px;
}

/* --------------------------------------------------------------------------
   Base
   -------------------------------------------------------------------------- */
.btn {
  /* layout */
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  box-sizing: border-box;
  /* default size = md */
  height: 40px;
  padding: 0 16px;
  /* type */
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 14px;
  font-weight: 600;
  line-height: 1;
  text-decoration: none;
  white-space: nowrap;
  /* shape */
  border: 1px solid transparent;
  border-radius: var(--pb-radius);
  /* behavior */
  cursor: pointer;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  transition: background-color .15s ease, border-color .15s ease,
              color .15s ease, box-shadow .15s ease, opacity .15s ease;
}

.btn:focus-visible {
  outline: none;
  /* teal-400 at 50% opacity */
  box-shadow: 0 0 0 3px rgba(45, 212, 191, 0.5);
}

.btn:disabled,
.btn[disabled],
.btn.is-disabled,
.btn[aria-disabled="true"] {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* --------------------------------------------------------------------------
   Variants
   -------------------------------------------------------------------------- */

/* Primary — teal fill */
.btn-primary {
  background-color: var(--pb-teal);
  border-color: var(--pb-teal);
  color: #ffffff;
}
.btn-primary:hover {
  background-color: var(--pb-teal-hover);
  border-color: var(--pb-teal-hover);
}
.btn-primary:active {
  background-color: var(--pb-teal-active);
  border-color: var(--pb-teal-active);
}

/* Secondary — zinc-800 fill */
.btn-secondary {
  background-color: var(--pb-zinc-800);
  border-color: var(--pb-zinc-800);
  color: #f4f4f5;
}
.btn-secondary:hover {
  background-color: var(--pb-zinc-700);
  border-color: var(--pb-zinc-700);
}
.btn-secondary:active {
  background-color: #18181b;
  border-color: #18181b;
}

/* Ghost — transparent + teal border */
.btn-ghost {
  background-color: transparent;
  border-color: var(--pb-teal);
  color: var(--pb-teal);
}
.btn-ghost:hover {
  background-color: var(--pb-teal);
  color: #ffffff;
}
.btn-ghost:active {
  background-color: var(--pb-teal-active);
  border-color: var(--pb-teal-active);
  color: #ffffff;
}

/* Danger — red-600 */
.btn-danger {
  background-color: var(--pb-red-600);
  border-color: var(--pb-red-600);
  color: #ffffff;
}
.btn-danger:hover {
  background-color: var(--pb-red-700);
  border-color: var(--pb-red-700);
}
.btn-danger:active {
  background-color: #991b1b;
  border-color: #991b1b;
}

/* --------------------------------------------------------------------------
   Sizes
   -------------------------------------------------------------------------- */
.btn-sm {
  height: 32px;
  padding: 0 12px;
  font-size: 13px;
}
.btn-md {
  height: 40px;
  padding: 0 16px;
  font-size: 14px;
}
.btn-lg {
  height: 48px;
  padding: 0 24px;
  font-size: 16px;
}

/* --------------------------------------------------------------------------
   Mobile — 44px minimum touch target on md/lg (Apple HIG)
   -------------------------------------------------------------------------- */
@media (max-width: 640px), (pointer: coarse) {
  .btn-md,
  .btn-lg {
    min-height: 44px;
  }
  /* iOS zooms any focused input under 16px — force 16px on inputs paired
     with buttons (same .btn-group / form row) to prevent the zoom jump. */
  .btn-group input,
  .btn-group select,
  .btn-group textarea,
  form .btn ~ input,
  form input.btn-input {
    font-size: 16px;
  }
}

/* Optional layout helper for button + input rows */
.btn-group {
  display: inline-flex;
  align-items: stretch;
  gap: 8px;
}

/* --------------------------------------------------------------------------
   Icon-only / compact buttons — toolbar icons + table-row actions.
   Shared + canonical (NOT redefined per dashboard). Preserves the legacy
   compact ghost look so the header toolbar and row-delete icons do not
   balloon when dashboards adopt the canonical system.
   -------------------------------------------------------------------------- */
.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  background: transparent;
  border: 1px solid transparent;
  padding: 6px 12px;
  border-radius: 8px;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 13px;
  line-height: 1;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  transition: background-color .15s ease, border-color .15s ease, color .15s ease;
}
.dark .icon-btn        { border-color: #334155; color: #cbd5e1; }
html:not(.dark) .icon-btn { border-color: #cbd5e1; color: #1e293b; }
.icon-btn:hover        { background: rgba(20, 184, 166, 0.10); }
.icon-btn:focus-visible { outline: none; box-shadow: 0 0 0 3px rgba(45, 212, 191, 0.5); }
.icon-btn:disabled,
.icon-btn[disabled]    { opacity: 0.5; cursor: not-allowed; pointer-events: none; }