* { box-sizing: border-box; user-select: none; -webkit-tap-highlight-color: transparent; }

body {
    background: #dfe6e9;
    margin: 20px;
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

.main-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 20px;
    background: #2c3e50;
    color: white;
    padding: 12px 24px;
    border-radius: 60px;
    box-shadow: 0 8px 12px rgba(0,0,0,0.2);
}

.main-header h1 {
    margin: 0;
    font-size: 2.2rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.header-actions {
    margin-left: auto;
    display: flex;
    align-items: center;
    gap: 12px;
}

.lang-select {
    background: #ecf0f1;
    border: 1px solid #cbd5e1;
    color: #2c3e50;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 40px;
    padding: 10px 14px;
    cursor: pointer;
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
}

.lang-select:focus {
    outline: 2px solid #3b82f6;
    outline-offset: 2px;
}

.help-btn {
    background: #ecf0f1;
    border: none;
    color: #2c3e50;
    font-size: 1.8rem;
    font-weight: bold;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    transition: 0.2s;
    margin-left: 0;
}

.help-btn:hover { background: #bdc3c7; transform: scale(1.05); }
.help-btn:active { transform: scale(0.95); }

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    white-space: nowrap;
    border: 0;
}

.spec-panel {
    background: white;
    border-radius: 28px;
    box-shadow: 0 20px 35px -8px rgba(0,0,0,0.2);
    padding: 24px 20px 32px 20px;
    margin-bottom: 30px;
    border: 1px solid #b0c4d9;
}

.spec-panel h2 {
    font-size: 1.6rem;
    font-weight: 600;
    margin: 0 0 10px 0;
    color: #0f172a;
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
}

.spec-panel h2 small {
    font-size: 1rem;
    font-weight: 400;
    background: #e9eef3;
    color: #1e3a5f;
    padding: 4px 14px;
    border-radius: 40px;
}

.spec-toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin: 20px 0 25px 0;
    align-items: center;
}

.btn {
    background: white;
    border: 1px solid #cbd5e1;
    padding: 12px 26px;
    border-radius: 60px;
    font-size: 1.1rem;
    font-weight: 500;
    color: #1e293b;
    cursor: pointer;
    box-shadow: 0 4px 8px rgba(0,0,0,0.02);
    transition: 0.15s;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.btn-primary {
    background: #0f172a !important;
    border: 1px solid #0f172a !important;
    color: #ffffff !important;
    box-shadow: 0 4px 12px rgba(15, 23, 42, 0.3);
}

.btn-primary:hover { background: #1e293b !important; }
.btn:active { transform: scale(0.96); background: #e9eef3; }

.table-wrapper {
    overflow-x: auto;
    margin: 18px 0 28px 0;
    border-radius: 20px;
    border: 1px solid #dde3e9;
    background: #ffffff;
    box-shadow: 0 6px 12px rgba(0,0,0,0.04);
}

.spec-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 380px;
    font-size: 1.1rem;
}

.spec-table th {
    background: #f8fafc;
    font-weight: 600;
    color: #0b1e33;
    padding: 18px 10px;
    font-size: 1.2rem;
    border-bottom: 2px solid #b9c7d9;
}

.spec-table td {
    text-align: center;
    padding: 16px 8px;
    border-bottom: 1px solid #dde3e9;
    font-weight: 500;
}

.spec-table .fixed-col {
    background-color: #f2f6fc;
    font-weight: 600;
    color: #022b54;
}

.f-cell {
    cursor: pointer;
    font-weight: 700;
    font-size: 1.3rem;
    transition: 0.1s;
    border-radius: 16px;
    user-select: none;
    min-width: 75px;
    padding: 12px 8px;
    touch-action: manipulation;
}

.f-cell[data-val="0"] { background-color: #ffffff; color: #0f172a; }
.f-cell[data-val="0"]:hover { background-color: #f1f5f9; }
.f-cell[data-val="1"] { background-color: #fff3e3; color: #d97706; }
.f-cell[data-val="1"]:hover { background-color: #ffe0b9; }
.f-cell[data-val="X"] { background-color: #e2e8f0; color: #64748b; font-style: italic; }
.f-cell[data-val="X"]:hover { background-color: #cbd5e1; }

.kmap-wrapper {
    background: white;
    border-radius: 24px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    padding: 24px;
    margin: 25px 0 30px 0;
}

.kmap-title {
    text-align: center;
    margin-bottom: 15px;
    font-size: 1.45rem;
    color: #1e293b;
    font-weight: 600;
}

.kmap-table {
    border-collapse: collapse;
    margin: 0 auto;
    box-shadow: 0 4px 12px rgba(0,0,0,0.05);
}

.kmap-table th, .kmap-table td {
    width: 58px;
    height: 58px;
    text-align: center;
    vertical-align: middle;
    font-size: 1.45rem;
    border: 3px solid #e2e8f0;
    transition: all 0.2s;
}

.kmap-table th {
    background: #f1f5f9;
    font-weight: 700;
    color: #475569;
    font-size: 1rem;
}

.kmap-cell {
    cursor: pointer;
    font-weight: 700;
    touch-action: manipulation;
}

.kmap-cell[data-val="0"] { background: #f8fafc; color: #334155; }
.kmap-cell[data-val="1"] { background: #fefce8; color: #ca8a04; }
.kmap-cell[data-val="X"] { background: #ecfeff; color: #0e7490; font-style: italic; }
.kmap-cell:hover { transform: scale(1.15); box-shadow: 0 0 0 4px #3b82f6 inset; }

.expr-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.expr-box {
    background: #f0f4fa;
    border-radius: 24px;
    padding: 22px 25px;
    margin: 8px 0;
    border-left: 6px solid #1e293b;
}

.expr-box.simp-sop { border-left-color: #10b981; background: #ecfdf5; }
.expr-box.simp-pos { border-left-color: #8b5cf6; background: #f5f3ff; }

.expr-title {
    font-weight: 600;
    font-size: 1.1rem;
    color: #0b2b44;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.expr-output {
    background: #ffffffd6;
    padding: 16px 20px;
    border-radius: 20px;
    font-family: 'Courier New', Courier, monospace;
    font-size: 1.2rem;
    font-weight: 600;
    word-break: break-word;
    white-space: pre-wrap;
    line-height: 1.6;
    border: 1px solid #bacde0;
    box-shadow: inset 0 1px 5px #0000000d;
}

.d-care { color: #94a3b8; font-style: italic; }

#canvas {
    border: 3px solid #2c3e50;
    background-color: #f1f3f5;
    width: 100%;
    height: auto;
    display: block;
    border-radius: 20px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
    touch-action: none;
    margin-top: 20px;
}

.draggable { cursor: grab; touch-action: none; }
.draggable:active { cursor: grabbing; }

#toolbar {
    margin-bottom: 16px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    background: #e9ecef;
    padding: 16px 20px;
    border-radius: 40px;
    align-items: center;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

button {
    padding: 10px 18px;
    border: none;
    background: #3498db;
    color: white;
    font-weight: 600;
    border-radius: 40px;
    cursor: pointer;
    transition: 0.15s;
    box-shadow: 0 2px 6px rgba(0,0,0,0.2);
    min-width: 70px;
    font-size: 1rem;
    border: 1px solid rgba(255,255,255,0.3);
    touch-action: manipulation;
}

button:active { transform: scale(0.96); background: #2980b9; }
button.wire-active { background: #e67e22; box-shadow: 0 0 0 3px #f39c12; }
button.sim-active { background: #27ae60; box-shadow: 0 0 0 3px #2ecc71; }

.status-text {
    margin-left: auto;
    font-family: 'Fira Mono', monospace;
    font-weight: 600;
    color: #1e272e;
    background: white;
    padding: 8px 20px;
    border-radius: 40px;
    box-shadow: inset 0 1px 4px rgba(0,0,0,0.2);
    font-size: 0.95rem;
}

#helpModal {
    display: none;
    position: fixed;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    border: 2px solid #2c3e50;
    border-radius: 24px;
    padding: 30px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    z-index: 2000;
    max-width: 90vw;
    max-height: 85vh;
    overflow: auto;
}

#closeHelp {
    float: right;
    cursor: pointer;
    font-size: 28px;
    font-weight: bold;
    margin-left: 20px;
}

.overlay {
    display: none;
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1999;
}

@media (max-width: 768px) {
    .expr-grid { grid-template-columns: 1fr; }
    .btn { padding: 8px 16px; font-size: 1rem; }
    .main-header h1 { font-size: 1.8rem; }
    .header-actions { flex-wrap: wrap; justify-content: flex-end; }
}