/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.5;
    color: #333;
    background-color: #f5f5f5;
}

.gpa-calculator-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

h1 {
    text-align: center;
    margin-bottom: 2rem;
    color: #1a1a1a;
    font-size: 2.5rem;
}

/* Card Styles */
.card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    margin-bottom: 2rem;
}

.card-header {
    padding: 1.5rem;
    border-bottom: 1px solid #eee;
}

.card-header h2 {
    margin: 0;
    font-size: 1.5rem;
    color: #333;
}

.card-content {
    padding: 1.5rem;
}

/* Form Styles */
.form-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 1rem;
}

.form-group {
    margin-bottom: 1rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #666;
}

input, select {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
}

input:focus, select:focus {
    outline: none;
    border-color: #4a90e2;
    box-shadow: 0 0 0 2px rgba(74, 144, 226, 0.2);
}

.btn {
    background-color: #4a90e2;
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.2s;
}

.btn:hover {
    background-color: #357abd;
}

.btn:disabled {
    background-color: #ccc;
    cursor: not-allowed;
}

/* Table Styles */
.table-container {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 1rem;
}

th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #eee;
}

th {
    background-color: #f8f9fa;
    font-weight: 600;
}

.empty-table td {
    text-align: center;
    color: #666;
    padding: 2rem;
}

/* GPA Display Styles */
.gpa-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    align-items: center;
}

.stats p {
    color: #666;
    margin-bottom: 0.5rem;
}

.gpa-display {
    text-align: center;
}

.gpa-number {
    font-size: 2.5rem;
    font-weight: bold;
    color: #4a90e2;
    margin-bottom: 0.5rem;
}

.gpa-display p {
    color: #666;
}

/* Error Message */
.error {
    color: #dc3545;
    margin-top: 1rem;
    font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

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

    .gpa-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .gpa-display {
        margin-bottom: 1rem;
    }

    h1 {
        font-size: 2rem;
    }
}

/* Delete Button */
.delete-btn {
    background-color: #dc3545;
    color: white;
    border: none;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.875rem;
}

.delete-btn:hover {
    background-color: #c82333;
}