* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: #f8f9fa;
    padding: 15px;
    font-size: 13px;
}

.container {
    max-width: 850px;
    margin: 0 auto;
}

h1 {
    text-align: center;
    font-size: 18px;
    color: #2c3e50;
    margin-bottom: 5px;
}

.subtitle {
    text-align: center;
    color: #666;
    font-size: 12px;
    margin-bottom: 15px;
}

.comparison-table {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
    overflow: hidden;
}

.header-row {
    display: grid;
    grid-template-columns: 60px 1fr 1fr;
    background: #2c3e50;
    color: white;
    font-weight: bold;
    text-align: center;
}

.header-row > div {
    padding: 12px 10px;
    border-right: 1px solid rgba(255,255,255,0.2);
}

.header-row > div:last-child {
    border-right: none;
}

.data-row {
    display: grid;
    grid-template-columns: 60px 1fr 1fr;
    border-bottom: 1px solid #eee;
}

.data-row:last-child {
    border-bottom: none;
}

.level-col {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 10px;
    background: #f8f9fa;
}

.level-badge {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 14px;
    color: white;
}

.level-0 .level-badge { background: #95a5a6; }
.level-2 .level-badge { background: #3498db; }
.level-3 .level-badge { background: #f39c12; }
.level-4 .level-badge { background: #e67e22; }
.level-5 .level-badge { background: #e74c3c; }

.sae-col, .textbook-col {
    padding: 12px 15px;
    border-right: 1px solid #eee;
}

.textbook-col {
    border-right: none;
}

.data-row strong {
    display: block;
    color: #2c3e50;
    margin-bottom: 4px;
    font-size: 13px;
}

.data-row p {
    color: #666;
    font-size: 11px;
    line-height: 1.4;
}

.threshold-row {
    background: linear-gradient(90deg, #fff5f5 0%, #ffe5e5 50%, #fff5f5 100%);
    border-top: 2px dashed #e74c3c;
    border-bottom: 2px dashed #e74c3c;
}

.threshold-label {
    text-align: center;
    padding: 8px;
    color: #c0392b;
    font-weight: bold;
    font-size: 11px;
    letter-spacing: 1px;
}

.threshold-icon {
    margin: 0 8px;
}

.level-3, .level-4, .level-5 {
    background: linear-gradient(90deg, #fff 0%, #fff5f5 100%);
}

.key-insight {
    margin-top: 15px;
    padding: 12px 15px;
    background: #e8f6f3;
    border-left: 4px solid #1abc9c;
    border-radius: 4px;
    font-size: 12px;
    line-height: 1.5;
}

@media (max-width: 600px) {
    body {
        padding: 10px;
        font-size: 12px;
    }

    h1 {
        font-size: 15px;
    }

    .header-row, .data-row {
        grid-template-columns: 45px 1fr 1fr;
    }

    .level-badge {
        width: 26px;
        height: 26px;
        font-size: 12px;
    }

    .sae-col, .textbook-col {
        padding: 10px;
    }

    .data-row strong {
        font-size: 11px;
    }

    .data-row p {
        font-size: 10px;
    }
}