/* ===== UNIFIED BUTTON BASE ===== */
.quantum-btn {
    padding: 12px 10px;
    background: linear-gradient(135deg, rgba(212, 175, 55, 0.12), rgba(212, 175, 55, 0.05));
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    cursor: pointer;
    font-family: var(--font-main);
    font-size: 0.95em;
    font-weight: 500;
    color: var(--gold-light);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
}

.quantum-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(212, 175, 55, 0.15);
    transform: translate(-50%, -50%);
    transition: width 0.4s, height 0.4s;
}

.quantum-btn:hover::before {
    width: 200px;
    height: 200px;
}

.quantum-btn:hover {
    background: linear-gradient(135deg, rgba(212, 175, 55, 0.22), rgba(212, 175, 55, 0.12));
    border-color: var(--gold);
    transform: translateY(-2px);
    box-shadow: 0 6px 18px rgba(212, 175, 55, 0.25);
}

.quantum-btn:active {
    transform: translateY(0) scale(0.97);
    box-shadow: 0 2px 8px rgba(212, 175, 55, 0.2);
}

.quantum-btn.active {
    background: linear-gradient(135deg, var(--gold), var(--gold-dark));
    color: var(--black);
    border-color: var(--gold);
    box-shadow: 0 0 20px rgba(212, 175, 55, 0.5);
}

.quantum-btn.active::before {
    display: none;
}

.quantum-btn small {
    display: block;
    font-size: 0.72em;
    opacity: 0.7;
    margin-top: 3px;
}

.quantum-btn .btn-symbol {
    display: block;
    font-family: var(--font-main);
    font-size: 1.3em;
    font-weight: 700;
    margin-bottom: 2px;
    background: linear-gradient(135deg, var(--gold-light), var(--gold));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.quantum-btn.active .btn-symbol {
    -webkit-text-fill-color: var(--black);
    background: none;
}

.preset-grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.basis-group {
    margin-bottom: 15px;
}

.basis-group:last-child {
    margin-bottom: 0;
}

.basis-label {
    font-family: var(--font-main);
    font-size: 0.8em;
    color: rgba(212, 175, 55, 0.7);
    letter-spacing: 1px;
    margin-bottom: 8px;
    padding-left: 2px;
}

.animation-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}