/* =========================================================
   5.06 Fetch–Decode–Execute Widget
   ========================================================= */

.fde-widget {
    position: relative;
    margin: 1.5rem 0;
    padding: 1.5rem;
    border-radius: 28px;
    background:
        radial-gradient(circle at top left, rgba(219, 234, 254, 0.9), transparent 34%),
        #f8fafc;
    border: 1px solid #dbe3ef;
    box-shadow: 0 18px 45px rgba(15, 23, 42, 0.08);
    overflow: hidden;
}

.fde-top-panel {
    display: grid;
    grid-template-columns: 1.45fr 0.75fr;
    gap: 1rem;
    align-items: stretch;
}

.fde-register-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0.9rem;
}

.fde-register,
.fde-component,
.fde-memory-cell,
.fde-flow-step,
.fde-explanation-box {
    border-radius: 20px;
    background: white;
    border: 1px solid #e2e8f0;
    box-shadow: 0 10px 25px rgba(15, 23, 42, 0.05);
}

.fde-register {
    padding: 1rem;
    min-height: 120px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: transform 0.25s ease, border-color 0.25s ease, background 0.25s ease;
}

.fde-register-label {
    display: inline-flex;
    width: fit-content;
    padding: 0.25rem 0.55rem;
    border-radius: 999px;
    background: #eff6ff;
    color: #1d4ed8;
    font-weight: 800;
    font-size: 0.75rem;
    letter-spacing: 0.05em;
}

.fde-register strong {
    font-size: 1.25rem;
    color: #0f172a;
    word-break: break-word;
}

.fde-register small {
    color: #64748b;
    line-height: 1.35;
}

.fde-cpu-area {
    display: grid;
    gap: 0.9rem;
}

.fde-component {
    padding: 1rem;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 0.45rem;
    transition: all 0.25s ease;
}

.fde-component strong {
    color: #0f172a;
    font-size: 1.05rem;
}

.fde-component span {
    color: #64748b;
}

.fde-memory-panel {
    margin-top: 1rem;
}

.fde-memory-panel h3 {
    margin-bottom: 0.7rem;
}

.fde-memory-list {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.9rem;
}

.fde-memory-cell {
    padding: 0.85rem 1rem;
    display: grid;
    gap: 0.25rem;
    transition: all 0.25s ease;
}

.fde-memory-cell span {
    color: #64748b;
    font-size: 0.85rem;
    font-weight: 700;
}

.fde-memory-cell strong {
    color: #0f172a;
}

.fde-flow-panel {
    display: grid;
    grid-template-columns: repeat(6, minmax(120px, 1fr));
    gap: 0.75rem;
    margin-top: 1.2rem;
    overflow-x: auto;
    padding-bottom: 0.25rem;
}

.fde-flow-step {
    padding: 0.8rem 0.9rem;
    font-size: 0.85rem;
    font-weight: 700;
    color: #334155;
    text-align: center;
    min-height: 62px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.25s ease;
}

.fde-flow-step.active,
.fde-register.active,
.fde-component.active,
.fde-memory-cell.active {
    border-color: #2563eb;
    background: #dbeafe;
    transform: translateY(-2px);
}

.fde-flow-step.done {
    border-color: #22c55e;
    background: #dcfce7;
    color: #14532d;
}

.fde-controls {
    display: flex;
    gap: 0.65rem;
    flex-wrap: wrap;
    margin-top: 1.25rem;
}

.fde-explanation-box {
    margin-top: 1rem;
    padding: 1rem 1.15rem;
    color: #334155;
}

.fde-explanation-box h3 {
    margin-top: 0;
    margin-bottom: 0.45rem;
    color: #0f172a;
}

.fde-explanation-box p {
    margin-bottom: 0;
}

.fde-token {
    position: absolute;
    top: 1rem;
    right: 1rem;
    z-index: 3;
    padding: 0.35rem 0.65rem;
    border-radius: 999px;
    background: #0f172a;
    color: white;
    font-size: 0.8rem;
    font-weight: 800;
    opacity: 0;
    transform: translateY(-8px);
    transition: all 0.25s ease;
    pointer-events: none;
}

.fde-token.visible {
    opacity: 1;
    transform: translateY(0);
}

@media (max-width: 900px) {
    .fde-top-panel {
        grid-template-columns: 1fr;
    }

    .fde-register-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .fde-memory-list {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 560px) {
    .fde-register-grid {
        grid-template-columns: 1fr;
    }

    .fde-widget {
        padding: 1rem;
    }
}