/*---------- BODY ----------*/



body,html {
    scroll-behavior: smooth;
}

.welcome_theory {
    min-height: 600px;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 195px 0;

    background-color: #fff;
    background-image: url("img/grammar1.png");
    background-size: cover;
    background-position: center;
}

.welcome__heading_theory {
    margin-right: 800px;
    margin-bottom: 50px;
    font-size: 59px;
    width: 15%;
    line-height: 1;
    letter-spacing: 0.07em;

    text-transform: uppercase;
    color: #111;
}


/*---------- WELCOME BUTTONS ----------*/


.welcome__links > * + * {
    margin-left: 20px;
}
.welcome__links {
    position: relative;
    right: 330px;
}
.link-contrast {
    display: inline-block;
    padding: 10.67px 30px; 

    font-size: 16px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: #fff;

    border-radius: 4px;
    background: #69b9ff;
    transition: background-color 0.1s;
}
.link-contrast:hover {
    background-color: #7AC1FF;
}

.link-contrast:active {
    background-color: #1994FF;
}

.link {
    display: inline-block;
    padding: 10px 30px;

    font-size: 16px;
    letter-spacing: 0.12em;
    text-transform: uppercase;

    border: 1px solid #000;
    border-radius: 4px;
    transition: border-color 0.1s, background-color 0.1s;
}

.link:hover {
    background-color: rgba(255, 255, 255, 0.233);
    border-color: rgba(255,255,255, 0,5);
}

.link:active {
    background-color: rgba(0, 0, 0, 0.233);
}




/*---------- THEORY CONTENT ----------*/




.theory-content {
    padding: 40px 0;
    background-color: #fff;
    border-top: 1px solid #eee;
}

.theory-content h2 {
    font-size: 28px;
    color: #111;
    margin-bottom: 20px;
}

.subtopic {
    margin-bottom: 30px;
}

.subtopic h3 {
    font-size: 24px;
    color: #333;
    margin-bottom: 15px;
}

.content-placeholder {
    padding: 20px;
    border-radius: 8px;
    border: 1px solid #ddd;
}
.content-placeholder li {
    font-size: 20px;
    
}
.content-placeholder p {
    color: #333;
    font-size: 17px;
}


/*---------- EXAMPLES ----------*/


.content-placeholder .examples {
    background-color: #b5dbfc;
    width: 100%;
    padding: 10px;
    border-radius: 7px;
}
.content-placeholder .vocabulary-examples {
    background-color: #b5dbfc;
    width: 60%;
    padding: 3.5px;
    border-radius: 7px;
    margin: 0 left;
    text-align: center;
}

.content-placeholder p2 {
    font-size: 20px;
}
.content-placeholder summary {
    cursor: pointer;
    font-size: 20px;
}
details > summary::marker {
    display: none;
    content: ''; 
}
details > summary::before {

    content:url(img/right2.png);
}
details[open] > summary::before {
    content:url(img/down2.png);
}
.content-placeholder .title-tenses {
    text-align: center;
    font-size: 20px;
}

.content-placeholder img{
    width: 100%;
}




/*---------- ACCORDION STYLES ----------*/




    .theory__accordion {
        margin: 0 auto;
    }

    .accordion-item {
        border: 1px solid #ddd;
        border-radius: 4px;
        margin-bottom: 10px;
        overflow: hidden;
    }
    .accordion-item.active .accordion-content {
        max-height: 500px; 
    }


    .accordion-header {
        width: 100%;
        padding: 15px;
        font-size: 18px;
        text-align: left;
        background-color: #69b9ff;
        color: #fff;
        border: none;
        cursor: button;
        transition: background-color 0.3s;
    }
    .accordion-item .link-header {
        width: 100%;
        padding: 15px;
        font-size: 18px;
        text-align: left;
        background-color: #69b9ff;
        color: #fff;
        border: none;
        cursor: button;
        transition: background-color 0.3s;
    }

    .accordion-header:hover {
        background-color: #7AC1FF;
    }

    .accordion-header:active {
        background-color: #1994FF;
    }

    .accordion-content {
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease-out;
        background-color: #f9f9f9;
    }

    .accordion-content ul {
        list-style: none;
        padding: 0;
        margin: 0;
    }

    .accordion-content li {
        padding: 10px 15px;
        border-bottom: 1px solid #ddd;
    }

    .accordion-content li:last-child {
        border-bottom: none;
    }

    .accordion-content li a {
        text-decoration: none;
        color: #333;
        transition: color 0.3s;
    }

    .accordion-content li a:hover {
        color: #69b9ff;
    }

.grammar-table {
    max-width: 800px;
    margin: 20px auto;
    overflow-x: auto;
}

.grammar-table .table {
    width: 100%;
    border-collapse: collapse;
    background: #fff;
    box-shadow: 0 2px 15px rgba(0,0,0,0.1);
}
.vocabulary-table-common {
    width: 60%;
    border-collapse: collapse;
    margin: 0 left;
    background: #fff;
    box-shadow: 0 2px 15px rgba(0,0,0,0.1);
}

.vocabulary-table-common tr td:nth-child(2) {
    letter-spacing: 2.5px;
}

td {
    width: 25%;
}

th, td {
    padding: 20px;
    border: 1px solid #ddd;
    text-align: left;
}

th {
    padding: 10px;
    background-color: #69b9ff;
    color: #fff;
    font-weight: 600;
}

td {
    background-color: #f9f9f9;
}

td strong,b {
    color: #333;
    font-weight: 600;
}




/*---------- QUESTION DIV SECTION TEXTS ----------*/




.question {
    margin: 20px;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
}

.question-button {
    margin: 15px;
    padding: 8px 18px;
    font-size: 16px;
    cursor: pointer;
    border-radius: 4px;
    border: 1px solid #69b9ff;
}

.submit {
    margin: 15px;
    padding: 8px 18px;
    font-size: 16px;
    cursor: pointer;
    border-radius: 4px;
    border: 1px solid #69b9ff;
}
input {
    border: 1px solid #ddd;
}

input[type="text"] {
    padding: 3px;
    font-size: 14px;
    width: 115px;
    margin-left: 10px;
}

.result {
    margin-left: 10px;
    font-weight: bold;
}

.result.correct {
    color: green;
}

.result.wrong {
    color: red;
}


/*---------- VOCABULARY ----------*/

.content-placeholder details li {
    font-size: 17.5px;
    line-height: 28px;
}
.vocabulary-details {
    font-size: 16px;
    color: #333;
}   

.title {
    font-size: 25px;
    text-align: center;
    margin-bottom: 20px;
}
.feedback.correct {
    color: green;
}
.feedback.incorrect {
    color: red;
}