:root {
    --nand-primary: #14b8a6;
    --nand-primary-dark: #0d9488;
    --nand-primary-light: #5eead4;
    --nand-primary-bg: #ccfbf1;
    --nand-accent: #06b6d4;
    --nand-surface: #ffffff;
    --nand-surface-alt: #f0fdfa;
    --nand-border: #d1d5db;
    --nand-border-light: #e5e7eb;
    --nand-text: #111827;
    --nand-text-muted: #6b7280;
    --nand-text-light: #9ca3af;
    --nand-success: #10b981;
    --nand-error: #ef4444;
    --nand-shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --nand-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --nand-shadow-md: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --nand-shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --nand-radius: 16px;
    --nand-radius-sm: 12px;
    --nand-transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Calculator Wrapper */
.nand-calculator-wrapper {
    display: flex;
    flex-direction: column;
    gap: 32px;
    margin-bottom: 40px;
}

/* Section Badge */
.section-badge {
    display: inline-block;
    padding: 6px 16px;
    background: var(--nand-primary-bg);
    color: var(--nand-primary-dark);
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-radius: 20px;
    margin-bottom: 20px;
}

/* Single Gate Section */
.gate-section {
    background: linear-gradient(135deg, #f0fdfa 0%, #ffffff 100%);
    border: 2px solid var(--nand-border-light);
    border-radius: var(--nand-radius);
    padding: 32px;
    box-shadow: var(--nand-shadow);
}

.gate-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 24px;
}

.gate-input-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.gate-label {
    font-size: 14px;
    font-weight: 600;
    color: var(--nand-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.toggle-switch {
    display: flex;
    background: var(--nand-surface);
    border: 2px solid var(--nand-border);
    border-radius: var(--nand-radius-sm);
    padding: 4px;
    gap: 4px;
    position: relative;
}

.toggle-switch input[type="radio"] {
    position: absolute;
    opacity: 0;
    width: 0;
    height: 0;
}

.toggle-option {
    padding: 12px 24px;
    font-size: 18px;
    font-weight: 700;
    color: var(--nand-text-muted);
    cursor: pointer;
    border-radius: 8px;
    transition: var(--nand-transition);
    text-align: center;
    min-width: 60px;
    
}

.toggle-switch input[type="radio"]:checked + .toggle-option {
    background: var(--nand-primary);
    color: white;
    box-shadow: var(--nand-shadow-sm);
}

.toggle-switch input[type="radio"]:hover + .toggle-option {
    background: var(--nand-primary-bg);
    color: var(--nand-primary-dark);
}

.gate-operator {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    color: var(--nand-primary);
    font-weight: 700;
    font-size: 16px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.gate-equals {
    font-size: 32px;
    font-weight: 300;
    color: var(--nand-text-muted);
}

.gate-result-display {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.result-badge {
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--nand-primary) 0%, var(--nand-primary-dark) 100%);
    color: white;
    font-size: 36px;
    font-weight: 700;
    border-radius: 50%;
    box-shadow: var(--nand-shadow-md);
    
    transition: var(--nand-transition);
}

.result-label {
    font-size: 12px;
    font-weight: 600;
    color: var(--nand-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Bitwise Section */
.bitwise-section {
    background: var(--nand-surface);
    border: 2px solid var(--nand-border-light);
    border-radius: var(--nand-radius);
    padding: 32px;
    box-shadow: var(--nand-shadow);
}

.bitwise-inputs {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 24px;
    align-items: end;
}

.binary-input-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.binary-label {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    font-weight: 600;
    color: var(--nand-text);
}

.label-icon {
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--nand-primary);
    color: white;
    border-radius: 6px;
    font-weight: 700;
    font-size: 14px;
}

.input-wrapper {
    position: relative;
}

.binary-input {
    width: 100%;
    padding: 16px 20px;
    font-size: 18px;
    
    border: 2px solid var(--nand-border);
    border-radius: var(--nand-radius-sm);
    background: var(--nand-surface-alt);
    color: var(--nand-text);
    transition: var(--nand-transition);
    box-sizing: border-box;
}

.binary-input:focus {
    outline: none;
    border-color: var(--nand-primary);
    background: var(--nand-surface);
    box-shadow: 0 0 0 4px var(--nand-primary-bg);
}

.binary-input::placeholder {
    color: var(--nand-text-light);
}

.input-indicator {
    position: absolute;
    right: 12px;
    top: 50%;
    transform: translateY(-50%);
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--nand-border);
    transition: var(--nand-transition);
}

.binary-input:focus + .input-indicator {
    background: var(--nand-primary);
    box-shadow: 0 0 0 4px var(--nand-primary-bg);
}

.binary-operator {
    padding: 16px 20px;
    background: var(--nand-primary);
    color: white;
    font-weight: 700;
    font-size: 16px;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-radius: var(--nand-radius-sm);
    box-shadow: var(--nand-shadow);
}

.bitwise-result-container {
    margin-top: 24px;
    padding: 24px;
    background: var(--nand-surface-alt);
    border: 2px solid var(--nand-primary);
    border-radius: var(--nand-radius-sm);
    border-left: 4px solid var(--nand-primary);
}

.result-header-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--nand-border-light);
}

.result-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--nand-text);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.copy-btn {
    padding: 8px 12px;
    background: var(--nand-primary);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: var(--nand-transition);
    font-size: 14px;
    font-weight: 600;
}

.copy-btn:hover {
    background: var(--nand-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--nand-shadow);
}

.bitwise-result-display {
    
    font-size: 16px;
    line-height: 2;
    color: var(--nand-text);
}

.bitwise-result-display .result-line {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 0;
}

.bitwise-result-display .result-line strong {
    color: var(--nand-primary-dark);
    font-weight: 700;
    min-width: 80px;
}

/* Truth Table Cards */
.truth-table-cards {
    background: var(--nand-surface);
    border: 2px solid var(--nand-border-light);
    border-radius: var(--nand-radius);
    padding: 32px;
    box-shadow: var(--nand-shadow);
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.truth-card {
    background: var(--nand-surface-alt);
    border: 2px solid var(--nand-border-light);
    border-radius: var(--nand-radius-sm);
    padding: 20px;
    transition: var(--nand-transition);
    cursor: pointer;
}

.truth-card:hover {
    border-color: var(--nand-primary);
    box-shadow: var(--nand-shadow);
    transform: translateY(-2px);
}

.truth-card.active {
    background: var(--nand-primary-bg);
    border-color: var(--nand-primary);
    box-shadow: 0 0 0 4px var(--nand-primary-bg);
}

.card-inputs {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 16px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--nand-border-light);
}

.input-value {
    font-size: 14px;
    font-weight: 600;
    color: var(--nand-text-muted);
    
}

.card-output {
    display: flex;
    flex-direction: column;
    gap: 8px;
    align-items: center;
}

.output-label {
    font-size: 12px;
    font-weight: 600;
    color: var(--nand-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.output-value {
    font-size: 32px;
    font-weight: 700;
    color: var(--nand-primary-dark);
    
}

.truth-card.active .output-value {
    color: var(--nand-primary);
    transform: scale(1.1);
}

/* Toast Notification */
.toast-notification {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: var(--nand-success);
    color: white;
    padding: 16px 20px;
    border-radius: var(--nand-radius-sm);
    box-shadow: var(--nand-shadow-lg);
    display: none;
    z-index: 9999;
    animation: slideUp 0.3s ease-out;
    max-width: 320px;
}

.toast-notification.error {
    background: var(--nand-error);
}

.toast-content {
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 600;
}

@keyframes slideUp {
    from {
        transform: translateY(100px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* Mobile Responsive */
@media (max-width: 767px) {
    .gate-section,
    .bitwise-section,
    .truth-table-cards {
        padding: 20px;
    }

    .gate-controls {
        flex-direction: column;
        gap: 20px;
    }

    .gate-operator,
    .gate-equals {
        transform: rotate(90deg);
    }

    .bitwise-inputs {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .binary-operator {
        text-align: center;
        justify-self: center;
        width: fit-content;
    }

    .cards-grid {
        grid-template-columns: 1fr;
    }

    .result-badge {
        width: 60px;
        height: 60px;
        font-size: 28px;
    }

    .toggle-option {
        padding: 10px 20px;
        min-width: 50px;
    }

    .toast-notification {
        bottom: 16px;
        right: 16px;
        left: 16px;
        max-width: none;
    }
}