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

body {
    background-color: #fff;
    font-family: Arial, sans-serif;
    padding: 20px;
}

.main-wrapper {
    display: flex;
    gap: 20px;
    max-width: 900px;
}

.left-panel {
    width: 320px;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.box-style {
    border: 2px solid #7c7bad;
    background-color: #b8e2c3;
    padding: 15px;
    border-radius: 2px;
}

legend {
    font-size: 13px;
    color: #333;
    padding: 0 5px;
}

.radio-group {
    font-size: 14px;
    margin-bottom: 12px;
    line-height: 1.8;
}

.color-group {
    font-size: 14px;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.color-group input[type="color"] {
    width: 40px;
    height: 25px;
    border: 1px solid #999;
    cursor: pointer;
}

.btn-group {
    display: flex;
    gap: 8px;
}

.btn-group button {
    padding: 4px 8px;
    font-size: 12px;
    background-color: #e1e1e1;
    border: 1px solid #777;
    cursor: pointer;
}

.btn-group button:hover {
    background-color: #d0d0d0;
}

/* DANH SÁCH LI */
#itemList {
    padding-left: 25px;
}

#itemList li {
    background-color: #77acd4;
    color: #ffffff;
    padding: 4px 8px;
    margin-bottom: 6px;
    font-weight: bold;
    font-size: 13px;
    cursor: pointer;
}

#itemList li:hover {
    background-color: #2f6e8f;
}

/* CỘT PHẢI HIỂN THỊ CHỮ */
.right-panel {
    flex: 1;
}

.display-box {
    background-color: #b8e2c3;
    height: 100%;
    min-height: 320px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 60px;
    font-weight: bold;
    font-family: 'Times New Roman', Times, serif;
    color: #0000ff;
    transition: all 0.2s ease;
}

/* CLASS TẠO BÓNG CHỮ */
.text-shadow-effect {
    text-shadow: 2px 3px 7px rgba(0, 0, 0, 0.6);
}