/* General Card Style */
.card {
    background-color: #ffffff;
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    border: 1px solid #e9ecef;
}

/* How to Use Section */
.how-to-use h2 {
    text-align: center;
    margin-bottom: 2rem;
    color: #343a40;
}

.how-to-use .steps {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
}

@media (min-width: 768px) {
    .how-to-use .steps {
        grid-template-columns: repeat(3, 1fr);
    }
}

.how-to-use .step {
    text-align: center;
}

.how-to-use .step h3 {
    color: #007bff;
    margin-bottom: 0.5rem;
}

/* Review Tool App Section */
.review-tool-app h2 {
    margin-top: 0;
    margin-bottom: 1.5rem;
    color: #343a40;
}

.form-container {
    margin-bottom: 2rem;
}

#add-item-form {
    display: flex;
    gap: 0.5rem;
}

#item-title {
    flex-grow: 1;
    padding: 0.75rem 1rem;
    border: 1px solid #ced4da;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.2s, box-shadow 0.2s;
}

#item-title:focus {
    border-color: #80bdff;
    outline: 0;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}

#add-item-form button {
    white-space: nowrap;
}

/* Study List */
.study-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.study-list li {
    display: grid;
    grid-template-columns: 1fr auto auto;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    border-radius: 8px;
    transition: background-color 0.2s;
}

.study-list li:not(.empty-message):hover {
    background-color: #f8f9fa;
}

.study-list li:not(:last-child) {
    border-bottom: 1px solid #e9ecef;
}

.item-title {
    font-weight: 500;
}

.review-steps {
    display: flex;
    gap: 0.5rem;
}

.review-step {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.3rem 0.6rem;
    border-radius: 15px;
    font-size: 0.8rem;
    background-color: #e9ecef;
    cursor: pointer;
    transition: background-color 0.2s;
}

.review-step:hover {
    background-color: #d1d9e0;
}

.review-step.completed {
    background-color: #d4edda; /* Light green */
    text-decoration: line-through;
    color: #555;
}

.review-step input[type="checkbox"] {
    cursor: pointer;
}

.delete-btn {
    background: none;
    border: none;
    color: #adb5bd;
    font-size: 1.5rem;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.2s;
    padding: 0 0.5rem;
}

.delete-btn:hover {
    color: #dc3545; /* Red */
}

.empty-message {
    text-align: center;
    color: #6c757d;
    padding: 2rem;
}

/* Responsive Adjustments */
@media (max-width: 600px) {
    .study-list li {
        grid-template-columns: 1fr auto;
        grid-template-areas:
            "title delete"
            "steps steps";
    }
    .item-title { grid-area: title; }
    .review-steps { grid-area: steps; justify-content: center; margin-top: 0.5rem; }
    .delete-btn { grid-area: delete; }
}