/* ================================
   Buttons: Phượng Hoàng V2
   Primary, Secondary, Ghost, Danger,
   Icon buttons, Floating Zalo
   ================================ */

/* ── Base Button ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--ph-space-2xs);
  height: 44px;
  padding: 0 var(--ph-space-md);
  font: var(--ph-text-button);
  border: none;
  border-radius: var(--ph-radius-sm);
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  transition: background var(--ph-duration-fast) var(--ph-ease-out),
              transform var(--ph-duration-instant) var(--ph-ease-in-out),
              box-shadow var(--ph-duration-fast) var(--ph-ease-out);
  -webkit-user-select: none;
  user-select: none;
}

.btn:active {
  transform: scale(0.97);
}

.btn:disabled,
.btn.disabled {
  opacity: var(--ph-opacity-disabled);
  cursor: not-allowed;
  pointer-events: none;
  transform: none;
}

/* ── Button Sizes ── */
.btn-lg {
  height: 52px;
  padding: 0 var(--ph-space-lg);
  font: var(--ph-text-button);
  font-size: 1.0625rem;
}

/* ── Primary Button ── */
.btn-primary {
  background: var(--ph-accent);
  color: var(--ph-text-on-accent);
}

.btn-primary:hover {
  background: var(--ph-accent-hover);
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: scale(0.97);
}

/* ── Secondary Button ── */
.btn-secondary {
  background: transparent;
  color: var(--ph-accent);
  border: var(--ph-border-width-medium) solid var(--ph-accent);
}

.btn-secondary:hover {
  background: var(--ph-accent-subtle);
  transform: translateY(-1px);
}

/* ── Ghost Button ── */
.btn-ghost {
  background: transparent;
  color: var(--ph-text-secondary);
}

.btn-ghost:hover {
  background: var(--ph-surface-secondary);
  color: var(--ph-text-primary);
  transform: translateY(-1px);
}

/* ── Danger Button ── */
.btn-danger {
  background: var(--ph-danger);
  color: var(--ph-text-on-accent);
}

.btn-danger:hover {
  background: var(--ph-danger);
  transform: translateY(-1px);
}

/* ── Icon Button ── */
.btn-icon {
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: var(--ph-border-width-thin) solid var(--ph-border-default);
  border-radius: var(--ph-radius-sm);
  color: var(--ph-text-secondary);
  cursor: pointer;
  transition: all var(--ph-duration-fast) var(--ph-ease-out);
}

.btn-icon:hover {
  border-color: var(--ph-border-hover);
  color: var(--ph-accent);
}

.btn-icon:active {
  transform: scale(0.95);
}

/* ── Loading Spinner ── */
.btn-spinner {
  width: 16px;
  height: 16px;
  border: 2px solid transparent;
  border-top-color: currentColor;
  border-radius: 50%;
  animation: btn-spin 0.6s linear infinite;
}

@keyframes btn-spin {
  to { transform: rotate(360deg); }
}

/* ── Button Group ── */
.btn-group {
  display: flex;
  gap: var(--ph-space-sm);
  flex-wrap: wrap;
}

@media (max-width: 767px) {
  .btn-group {
    flex-direction: column;
  }
  .btn-group .btn {
    width: 100%;
  }
}

/* ── Quote Button (Primary CTA, compact) ── */
.ph-btn-quote {
  display: inline-flex;
  align-items: center;
  padding: .65rem 1.35rem;
  background: var(--ph-accent);
  color: var(--ph-text-on-accent);
  border: none;
  border-radius: var(--ph-radius-sm);
  font-size: .875rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  font-family: var(--ph-font-body);
  transition: filter var(--ph-duration-fast), transform var(--ph-duration-fast);
  box-shadow: 0 2px 10px rgba(29,139,44,.14);
  min-height: 44px;
}
.ph-btn-quote:hover {
  filter: brightness(1.08);
  transform: translateY(-1px);
}

/* ── Zalo Button (Secondary, outlined) ── */
.ph-btn-zalo {
  display: inline-flex;
  align-items: center;
  padding: .65rem 1.35rem;
  background: var(--ph-surface-primary);
  color: var(--ph-accent);
  border: 1px solid var(--ph-accent);
  border-radius: var(--ph-radius-sm);
  font-size: .875rem;
  font-weight: 600;
  text-decoration: none;
  white-space: nowrap;
  font-family: var(--ph-font-body);
  transition: background var(--ph-duration-fast), color var(--ph-duration-fast);
  min-height: 44px;
}
.ph-btn-zalo:hover {
  background: var(--ph-accent-subtle);
}