/* =============================================
   Button Component — Mercuriale.io
   Unified button system using BEM-style modifiers.
   Uses double-dash (--) to avoid collision with
   existing single-dash (.btn-primary) in admin.css.
   ============================================= */

/* ── Base ── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    min-height: var(--touch-target-min);
    padding: 0.625rem 1.25rem;
    font-size: 0.9375rem;
    font-weight: 600;
    line-height: 1.4;
    text-decoration: none;
    border: 2px solid transparent;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: background-color var(--transition-normal),
                color var(--transition-normal),
                border-color var(--transition-normal),
                box-shadow var(--transition-normal),
                transform var(--transition-fast);
    white-space: nowrap;
    -webkit-tap-highlight-color: transparent;
}

.btn:hover {
    transform: translateY(-1px);
    text-decoration: none;
}

.btn:active {
    transform: translateY(0);
}

.btn:focus-visible {
    outline: 3px solid var(--mercuriale-coral);
    outline-offset: 2px;
}

.btn:disabled,
.btn.is-disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

/* ── Primary (Navy) ── */
.btn--primary {
    background-color: var(--mercuriale-navy);
    border-color: var(--mercuriale-navy);
    color: #fff;
}

.btn--primary:hover {
    background-color: var(--mercuriale-navy-light);
    border-color: var(--mercuriale-navy-light);
    color: #fff;
    box-shadow: 0 4px 12px rgba(30, 58, 95, 0.3);
}

.btn--primary:active {
    background-color: var(--mercuriale-navy-dark);
    border-color: var(--mercuriale-navy-dark);
}

/* ── Secondary (Coral) ── */
.btn--secondary {
    background-color: var(--mercuriale-coral);
    border-color: var(--mercuriale-coral);
    color: #fff;
}

.btn--secondary:hover {
    background-color: var(--mercuriale-coral-light);
    border-color: var(--mercuriale-coral-light);
    color: #fff;
    box-shadow: 0 4px 12px rgba(240, 117, 96, 0.3);
}

.btn--secondary:active {
    background-color: var(--mercuriale-coral-dark);
    border-color: var(--mercuriale-coral-dark);
}

/* ── Danger (Red) ── */
.btn--danger {
    background-color: var(--color-danger);
    border-color: var(--color-danger);
    color: #fff;
}

.btn--danger:hover {
    background-color: var(--color-danger-light);
    border-color: var(--color-danger-light);
    color: #fff;
    box-shadow: 0 4px 12px rgba(220, 38, 38, 0.3);
}

.btn--danger:active {
    background-color: #b91c1c;
    border-color: #b91c1c;
}

/* ── Success (Green) ── */
.btn--success {
    background-color: var(--color-success);
    border-color: var(--color-success);
    color: #fff;
}

.btn--success:hover {
    background-color: var(--color-success-light);
    border-color: var(--color-success-light);
    color: #fff;
    box-shadow: 0 4px 12px rgba(45, 106, 79, 0.3);
}

.btn--success:active {
    background-color: #1b4332;
    border-color: #1b4332;
}

/* ── Ghost (Transparent) ── */
.btn--ghost {
    background-color: transparent;
    border-color: transparent;
    color: var(--mercuriale-navy);
}

.btn--ghost:hover {
    background-color: var(--mercuriale-cream);
    color: var(--mercuriale-navy);
}

.btn--ghost:active {
    background-color: var(--mercuriale-cream-dark);
}

/* ── Outline (Navy border) ── */
.btn--outline {
    background-color: transparent;
    border-color: var(--mercuriale-navy);
    color: var(--mercuriale-navy);
}

.btn--outline:hover {
    background-color: var(--mercuriale-navy);
    border-color: var(--mercuriale-navy);
    color: #fff;
}

.btn--outline:active {
    background-color: var(--mercuriale-navy-dark);
    border-color: var(--mercuriale-navy-dark);
    color: #fff;
}

/* ── Icon-only (square 44x44) ── */
.btn--icon {
    width: var(--touch-target-min);
    min-height: var(--touch-target-min);
    padding: 0;
}

/* ── Size: Small ── */
.btn--sm {
    min-height: 36px;
    padding: 0.375rem 0.875rem;
    font-size: 0.8125rem;
    border-radius: var(--radius-md);
}

/* ── Size: Large ── */
.btn--lg {
    min-height: 52px;
    padding: 0.875rem 1.75rem;
    font-size: 1.0625rem;
}

/* ── Full Width ── */
.btn--full {
    width: 100%;
}

/* ── Loading State ── */
.btn--loading {
    position: relative;
    color: transparent !important;
    pointer-events: none;
}

.btn--loading::after {
    content: '';
    position: absolute;
    width: 1.25rem;
    height: 1.25rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: btn-spin 0.6s linear infinite;
}

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