/* Drag and Drop Styles */
.draggable-subject {
    background: #f8fafc;
    border: 1px solid var(--border-color);
    padding: 10px 15px;
    border-radius: 6px;
    cursor: grab;
    display: flex;
    justify-content: space-between;
    align-items: center;
    transition: all 0.2s;
    user-select: none;
}

.draggable-subject:hover {
    background: #f1f5f9;
    border-color: var(--primary);
}

.draggable-subject:active {
    cursor: grabbing;
}

.draggable-subject.dragging {
    opacity: 0.5;
    background: #e2e8f0;
}

.semester-dropzone {
    background: #f8fafc;
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 15px;
    min-height: 150px;
    transition: all 0.2s;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.semester-dropzone.drag-over {
    background: #ecfdf5;
    border-color: var(--primary);
}

.semester-header {
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 5px;
}

/* Remove button in semester */
.remove-subject-btn {
    background: none;
    border: none;
    color: var(--danger);
    cursor: pointer;
    font-size: 14px;
}
.remove-subject-btn:hover {
    color: darkred;
}

/* Modal Styles */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.55);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-overlay.active {
    display: flex;
}

.modal-content {
    background: var(--card-bg);
    width: 100%;
    max-width: 500px;
    border-radius: 12px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    overflow: hidden;
    animation: modalFadeIn 0.3s ease;
}

@keyframes modalFadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.modal-header {
    background: var(--primary);
    color: white;
    padding: 15px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.close-btn {
    background: none;
    border: none;
    color: white;
    font-size: 1.2rem;
    cursor: pointer;
    transition: opacity 0.2s;
}

.close-btn:hover {
    opacity: 0.8;
}

.modal-body {
    padding: 20px;
    max-height: 70vh;
    overflow-y: auto;
}

/* Assigned subject item interactive */
.assigned-subject-item {
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}
.assigned-subject-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 6px -1px rgba(0,0,0,0.1);
}
.assigned-subject-item.configured {
    border-left: 4px solid var(--primary);
}