body {
    margin: 0;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
}

button {
    background-color: #EFEFEF;
    border: 1px solid #767676;
    border-radius: 3px;
    cursor: pointer;
    box-shadow: 5px 4px 10px rgba(0, 0, 0, 0.1);
}

button:hover {
    background-color: #E5E5E5;
    border: 1px solid #4F4F4F;
}

button:active {
    background-color: #f5f5f5;
    box-shadow: none;
}




/*------------------------------------------*/
/*------------- PAGE - Index ---------------*/
/*------------------------------------------*/


#main-box {
    border: 1px solid black;
    padding: 20px;
    width: 40%;
    height: 50%;
    text-align: center;
    position: relative;
    overflow-y: scroll;
}

@media screen and (max-width: 700px) {
  #main-box {
    width: 80%;
    height: 60%;
  }
}

#main-box h1 {
    font-family: Verdana;
}

#main-box span, ul {
    font-family: 'Times New Roman', Times, serif;
}

#established-text {
    position: absolute;
    top: 10px;
    right: 10px;
    font-size: 13px;
}

@media screen and (max-width: 700px) {
  #established-text {
    display: none !important;
  }
}

.a-link-button {
    text-decoration: none;
    color: black;
    cursor: pointer;
    border: 1px solid #ccc;
    border-radius: 4px;
    background-color: #f0f0f0;
    padding: 6px 12px;
    /* max-width: 200px; */
    white-space: nowrap;
    height: 20px;
    line-height: 20px;
}

.a-link-button:hover {
  background-color: #e6e6e6;
}

#language-select {
    position: absolute;
    top: 10px;
    left: 10px;
    font-size: 20px;
}

.lang-selected {
    background-color: #d2d2d2;
}

#main-box span:not(.language-khmer) {
    display: block;
}





/*------------------------------------------*/
/*------------ PAGE - Courses --------------*/
/*------------------------------------------*/


#courses-main-box {
    border: 1px solid black;
    padding: 20px;
    width: 50%;
    height: 80vh;
    text-align: center;
    position: relative;
    overflow-y: scroll;
    box-sizing: border-box;
}

#path-box {
    position: relative;
    padding: 10px;
    border: 1px solid black;
    width: 15%;
    overflow-y: scroll;
    height: 80vh;
    box-sizing: border-box;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 15px;
}

#file-explorer {
    border: 1px solid black;
    width: 99%;
    height: 92%;
    padding-top: 10px;
    padding-left: 10px;
    box-sizing: border-box;
    overflow: scroll;
    text-align: left;
}

#path-input {
    width: 90%;
}

.folder-name {
    font-weight: bold;
}

.folder-name, #file-explorer li {
    cursor: pointer;
}

#file-explorer ul {
    list-style-position: inside;
    padding-left: 20px; 
    margin: 5px 0;
}

#file-courses li {
    list-style: none;
}

#file-courses li::before {
    content: "\1F4DA  ";
}

#file-explorer a {
    text-decoration: none;
    color: black;
}

#back-to-course-page {
    position: absolute;
    top: 5;
    left: 15;
}

#back-to-course-page > a {
    text-decoration: none;
    color: black;
}








/*------------------------------------------*/
/*---------- PAGE - Course Page ------------*/
/*------------------------------------------*/



#course-main-box {
    border: 1px solid black;
    width: 50%;
    height: 80vh;
    width: 50%;
    position: relative;
    overflow-y: scroll;
    box-sizing: border-box;
    padding-top: 40px;
    padding-left: 2%;
}

#back-to-courses {
    position: absolute;
    top: 5;
    left: 15;
}

#back-to-courses > a {
    text-decoration: none;
    color: black;
}



#path-box-lessons {
    position: relative;
    padding: 10px;
    border: 1px solid black;
    width: 15%;
    overflow-y: scroll;
    height: 80vh;
    box-sizing: border-box;
    text-align: center;
    display: flex;
    flex-direction: column;
    gap: 15px;
    padding-top: 17px;
}

#file-explorer-lessons {
    border: 1px solid black;
    width: 99%;
    height: 93%;
    padding-top: 10px;
    padding-left: 10px;
    box-sizing: border-box;
    overflow: scroll;
    text-align: left;
}

#file-explorer-lessons li {
    cursor: pointer;
    list-style: none;
}

#file-explorer-lessons ul {
    list-style-position: inside;
    padding-left: 20px; 
    margin: 5px 0;
}

#file-explorer-lessons li::before {
    content: "📖 ";
}

#file-explorer-lessons li {
    font-weight: 600;
    font-family: sans-serif;
    margin-bottom: 5px;
    width: 100px;
    padding: 3px;
}

#file-explorer-lessons li:hover {
    background-color: rgba(65, 179, 255, 1);
}

.responsive-img {
    width: 100%;
    height: auto;
    max-width: 600px;
}

#course-main-box b {
    font-family: 'Trebuchet MS';
}

.tip {
    background-color: antiquewhite;
    width: 90%;
    border-radius: 3px;
    box-shadow: 3px 3px 10px rgba(0, 0, 0, 0.3);
    padding: 3px;
}

.tip::before {
    content: "💡 TIP: ";
}

.font-verdana {
    font-family: Verdana;
}

.language-khmer {
    display: none;
    /* margin: 0; */
    /* line-height: 1.2; */
}



/*------------------------------------------*/
/*---------- PAGE - Other Page ------------*/
/*------------------------------------------*/

#other-main-box {
    border: 1px solid black;
    padding: 20px;
    width: 50%;
    height: 80vh;
    text-align: center;
    position: relative;
    overflow-y: scroll;
    box-sizing: border-box;
}

.a-link-long-button {
    text-decoration: none;
    color: black;
    cursor: pointer;
    border: 1px solid #ccc;
    border-radius: 4px;
    background-color: #f0f0f0;
    padding: 6px 40px;
}

.a-link-long-button:hover {
  background-color: #e6e6e6;
}









/*------------------------------------------*/
/*-------- PAGE - Acknowledgements ---------*/
/*------------------------------------------*/

.acknowledgement_box {
    border: 1px solid black;
    background-color: lightblue;
    height: 200px;
    box-sizing: border-box;

    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    cursor: grab;
    user-select: none;
    gap: 5px;
}

.acknowledgement_name {
    font-size: 50px;
    font-family: Verdana;
}

.acknowledgement_box:hover {
    background-color: rgb(142, 176, 186);
}

.acknowledgement_desc {
    font-size: 17px;
    font-family: Verdana;
}