#sec-calendar-wrapper {
    max-width: 800px;
    margin: 0 auto;
    font-family: sans-serif;
}

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

#sec-calendar-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 5px;
}

.sec-day-header {
    font-weight: bold;
    text-align: center;
    padding: 10px;
    background: #f0f0f0;
}

.sec-day {
    border: 1px solid #ddd;
    min-height: 100px;
    padding: 5px;
    cursor: pointer;
    position: relative;
    background: #fff;
}

.sec-day:hover {
    background: #f9f9f9;
}

.sec-day.empty {
    background: #fcfcfc;
    cursor: default;
}

.sec-date-num {
    font-weight: bold;
    display: block;
    margin-bottom: 5px;
}

.sec-event-item {
    color: #333;
    padding: 2px 5px;
    font-size: 0.8em;
    margin-bottom: 2px;
    border-radius: 3px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    cursor: pointer;
    /* To indicate clickable */
}

.sec-event-item.external {
    border-left: 3px solid #0073aa;
    /* Example indicator */
}

/* Modal */
.sec-modal {
    position: fixed;
    z-index: 9999;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.4);
}

.sec-modal-content {
    background-color: #fefefe;
    margin: 10% auto;
    /* Slightly higher */
    padding: 20px;
    border: 1px solid #888;
    width: 350px;
    /* Wider for form */
    border-radius: 5px;
    position: relative;
}

.sec-close,
.sec-close-reg,
.sec-close-view {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.sec-close:hover,
.sec-close:focus,
.sec-close-reg:hover,
.sec-close-reg:focus,
.sec-close-view:hover,
.sec-close-view:focus {
    color: black;
    text-decoration: none;
    cursor: pointer;
}

.sec-modal-content input,
.sec-modal-content textarea,
.sec-modal-content select {
    /* Include select */
    width: 100%;
    margin-bottom: 10px;
    padding: 5px;
    box-sizing: border-box;
    /* Ensure padding doesn't affect width overflow */
}

.sec-modal-content button {
    background: #0073aa;
    color: #fff;
    border: none;
    padding: 8px 15px;
    cursor: pointer;
    border-radius: 3px;
    width: 100%;
    /* Full width button */
}

.sec-mobile-weekday {
    display: none;
    font-size: 0.9em;
    font-weight: normal;
    margin-left: 5px;
}

/* Month Info Section */
#sec-month-info h4 {
    margin-top: 0;
    margin-bottom: 10px;
    border-bottom: 1px solid #eee;
    padding-bottom: 5px;
}

.sec-month-course-item {
    margin-bottom: 15px;
    padding: 10px;
    background: #f9f9f9;
    border: 1px solid #eee;
    border-radius: 4px;
}

.sec-month-course-title {
    font-weight: bold;
    font-size: 1.1em;
}

.sec-month-course-fee {
    float: right;
    font-weight: bold;
    color: #d54e21;
}

/* Responsive Styles */
@media screen and (max-width: 600px) {
    #sec-calendar-grid {
        display: block;
    }

    .sec-day-header {
        display: none;
    }

    .sec-day.empty {
        display: none;
    }

    .sec-day {
        min-height: auto;
        padding: 10px;
        margin-bottom: 5px;
        border: 1px solid #ddd;
    }

    .sec-date-num {
        font-size: 1.1em;
        margin-bottom: 5px;
        display: flex;
        align-items: center;
    }

    .sec-mobile-weekday {
        display: inline;
    }

    .sec-event-item {
        font-size: 0.9em;
        padding: 3px 5px;
        margin-bottom: 3px;
        white-space: normal;
        /* Allow wrap on mobile vertical? */
        overflow: visible;
        text-overflow: clip;
    }

    .sec-modal-content {
        width: 90%;
        margin: 20% auto;
    }
}