/* ─── BUTTON BASE ─── */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--pb-space-2);
    padding: var(--pb-space-3) var(--pb-space-6);
    min-height: 44px;
    font-family: var(--pb-font-display);
    font-size: var(--pb-text-sm);
    font-weight: var(--pb-weight-semibold);
    letter-spacing: 0.04em;
    text-transform: uppercase;
    border-radius: var(--pb-radius-md);
    border: 2px solid transparent;
    cursor: pointer;
    transition: background-color var(--pb-transition-fast),
                border-color var(--pb-transition-fast),
                color var(--pb-transition-fast),
                box-shadow var(--pb-transition-fast),
                transform var(--pb-transition-fast);
    text-decoration: none;
    white-space: nowrap;
    line-height: 1;
}

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

.btn:active { transform: translateY(1px); }

/* ─── PRIMARY ─── */
.btn-primary {
    background-color: var(--pb-blue);
    color: var(--pb-white);
    border-color: var(--pb-blue);
}

.btn-primary:hover {
    background-color: var(--pb-blue-dark);
    border-color: var(--pb-blue-dark);
    color: var(--pb-white);
    box-shadow: 0 4px 16px rgba(30, 136, 210, 0.35);
}

/* ─── SECONDARY (outline) ─── */
.btn-secondary {
    background-color: transparent;
    color: var(--pb-blue);
    border-color: var(--pb-blue);
}

.btn-secondary:hover {
    background-color: var(--pb-blue);
    color: var(--pb-white);
}

/* ─── WHITE (for dark backgrounds) ─── */
.btn-white {
    background-color: var(--pb-white);
    color: var(--pb-navy);
    border-color: var(--pb-white);
}

.btn-white:hover {
    background-color: var(--pb-gray-100);
    color: var(--pb-blue);
}

/* ─── GHOST (for dark backgrounds) ─── */
.btn-ghost {
    background-color: transparent;
    color: var(--pb-white);
    border-color: rgba(255,255,255,0.4);
}

.btn-ghost:hover {
    background-color: rgba(255,255,255,0.1);
    border-color: var(--pb-white);
}

/* ─── SIZES ─── */
.btn-sm {
    padding: var(--pb-space-2) var(--pb-space-4);
    font-size: var(--pb-text-xs);
}

.btn-lg {
    padding: var(--pb-space-4) var(--pb-space-8);
    font-size: var(--pb-text-base);
    border-radius: var(--pb-radius-lg);
}