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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
}

header {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

header h1 {
    color: #333;
    font-size: 2rem;
}

.gpa-display {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 15px 30px;
    border-radius: 10px;
    color: white;
}

.gpa-label {
    font-size: 0.9rem;
    opacity: 0.9;
    margin-right: 10px;
}

.gpa-value {
    font-size: 2rem;
    font-weight: bold;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.section-header h2,
.section-header h3 {
    color: #333;
}

.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
}

.btn-primary {
    background: #667eea;
    color: white;
}

.btn-primary:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
}

.btn-danger {
    background: #dc3545;
    color: white;
}

.btn-danger:hover {
    background: #c82333;
}

.courses-section {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.courses-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.course-card {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    padding: 25px;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    border-color: #667eea;
}

.course-card h3 {
    color: #333;
    margin-bottom: 10px;
    font-size: 1.3rem;
}

.course-info {
    display: flex;
    justify-content: space-between;
    margin-top: 15px;
    padding-top: 15px;
    border-top: 2px solid rgba(0, 0, 0, 0.1);
}

.course-info-item {
    text-align: center;
}

.course-info-label {
    font-size: 0.8rem;
    color: #666;
    display: block;
    margin-bottom: 5px;
}

.course-info-value {
    font-size: 1.2rem;
    font-weight: bold;
    color: #667eea;
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: #666;
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.empty-state p {
    font-size: 1.1rem;
    margin-bottom: 20px;
}

.course-view {
    background: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.course-view-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 15px;
}

.course-view-header h2 {
    color: #333;
    flex-grow: 1;
}

.course-grade-display {
    background: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
    padding: 20px;
    border-radius: 10px;
    color: white;
    text-align: center;
    margin-bottom: 30px;
}

.grade-label {
    font-size: 1rem;
    opacity: 0.9;
    display: block;
    margin-bottom: 10px;
}

.grade-value {
    font-size: 3rem;
    font-weight: bold;
}

.assignments-section {
    margin-top: 30px;
}

.assignments-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.assignment-card {
    background: #f8f9fa;
    padding: 20px;
    border-radius: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-left: 4px solid #667eea;
}

.assignment-info h4 {
    color: #333;
    margin-bottom: 8px;
}

.assignment-details {
    display: flex;
    gap: 20px;
    font-size: 0.9rem;
    color: #666;
}

.assignment-grade {
    text-align: right;
}

.assignment-grade-value {
    font-size: 1.8rem;
    font-weight: bold;
    color: #667eea;
    display: block;
}

.assignment-weight {
    font-size: 0.85rem;
    color: #666;
}

.delete-assignment-btn {
    background: #dc3545;
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.9rem;
}

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

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
}

.modal-content {
    background: white;
    padding: 0;
    border-radius: 15px;
    width: 90%;
    max-width: 500px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
}

.modal-header {
    padding: 25px;
    border-bottom: 1px solid #e9ecef;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    color: #333;
    margin: 0;
}

.close-btn {
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: #999;
    line-height: 1;
}

.close-btn:hover {
    color: #333;
}

.modal-body {
    padding: 25px;
}

.modal-body label {
    display: block;
    margin-bottom: 8px;
    color: #333;
    font-weight: 600;
}

.modal-body input {
    width: 100%;
    padding: 12px;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    font-size: 1rem;
    margin-bottom: 20px;
    transition: border-color 0.3s ease;
}

.modal-body input:focus {
    outline: none;
    border-color: #667eea;
}

.modal-body small {
    display: block;
    margin-top: -15px;
    margin-bottom: 20px;
    color: #666;
    font-size: 0.85rem;
}

.modal-footer {
    padding: 20px 25px;
    border-top: 1px solid #e9ecef;
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

.hidden {
    display: none !important;
}

@media (max-width: 768px) {
    header {
        flex-direction: column;
        text-align: center;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .courses-list {
        grid-template-columns: 1fr;
    }

    .course-view-header {
        flex-direction: column;
        align-items: stretch;
    }

    .assignment-card {
        flex-direction: column;
        align-items: flex-start;
        gap: 15px;
    }

    .assignment-grade {
        text-align: left;
    }
}