@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;600;700&display=swap');

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    background-color: #f4f7f6;
    color: #2c3e50;
}

header {
    background-color: #1a252f;
    color: #ffffff;
    padding: 1.5rem 1rem;
    text-align: center;
}

header h1 {
    margin: 0 0 0.5rem 0;
    font-weight: 700;
}

header p {
    margin: 0;
    font-weight: 300;
    opacity: 0.9;
}

.dashboard {
    max-width: 1200px;
    margin: 30px auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 480px 1fr;
    gap: 25px;
}

.card {
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    padding: 25px;
    margin-bottom: 25px;
}

h2 {
    font-weight: 600;
    color: #2980b9;
    border-bottom: 2px solid #ecf0f1;
    padding-bottom: 10px;
    margin-top: 0;
    font-size: 1.25rem;
}

/* Inline Equation Builder */
.equation-inline {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 6px;
    background: #e8f4f8;
    padding: 20px 10px;
    border-radius: 8px;
    border-left: 5px solid #2980b9;
    font-size: 1.4rem;
    margin-top: 15px;
}

.math-text {
    font-weight: 700;
    color: #1a252f;
    font-family: 'Inter', sans-serif;
}

.input-group {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.math-input {
    width: 60px;
    font-size: 1.1rem;
    padding: 6px 4px;
    text-align: center;
    border: 2px solid #bdc3c7;
    border-radius: 6px;
    background: #fff;
    font-family: inherit;
    font-weight: 600;
    color: #2980b9;
    transition: border-color 0.2s;
}

.func-select {
    width: 75px;
    cursor: pointer;
    padding: 6px 2px;
}

.math-input:focus {
    border-color: #3498db;
    outline: none;
}

.input-label {
    font-size: 0.65rem;
    color: #7f8c8d;
    margin-top: 4px;
    font-family: 'Inter', sans-serif;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

/* Properties Panel */
.prop-item {
    margin-bottom: 12px;
    font-size: 0.95rem;
    line-height: 1.4;
}

.prop-label {
    font-weight: 700;
    color: #34495e;
    display: block;
    margin-bottom: 2px;
}

.prop-value {
    color: #00008b;
    font-family: Georgia, serif;
    font-size: 1.05rem;
    background: #eef2f5;
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 600;
}

footer {
    text-align: center;
    padding: 30px 20px;
    color: #95a5a6;
    font-size: 0.9rem;
    font-family: 'Inter', sans-serif;
}

.chart-container {
    position: relative;
    height: 600px;
    width: 100%;
}

/* Review Section */
.review-container {
    max-width: 1200px;
    margin: 10px auto 50px auto;
    padding: 0 20px;
}

.review-title {
    text-align: center;
    font-size: 1.8rem;
    margin-bottom: 25px;
    color: #1a252f;
    border-bottom: none;
}

.review-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 25px;
}

.review-card {
    margin-bottom: 0;
    display: flex;
    flex-direction: column;
}

.explanation {
    background-color: #f8f9fa;
    padding: 15px 20px;
    border-radius: 8px;
    border-left: 4px solid #3498db;
    flex-grow: 1;
}

.explanation p {
    margin: 10px 0;
    font-size: 0.95rem;
}

.explanation strong {
    color: #2c3e50;
}

/* Responsive Design */
@media (max-width: 900px) {
    .dashboard {
        grid-template-columns: 1fr;
    }
    .chart-container {
        height: 400px;
    }
}