:root {
    --bg-color: #e0e0e0;
    --card-bg-color: #303030;
    --header-card-bg-color: #f7f7f7;
    --text-color: #000000;
    --text-color-2: #ffffff;
    --accent-color: #008653;
    --accent-color-2: #00b46f;
    --medium-gray: #757575;
    --button-gray: #505050;
    --font-logo: 'knewave', cursive;
    --font-body: 'Roboto', sans-serif;
    --underline-color: #ffffff;

    /* GAME VARIABLES */
    --game-bg-color: #3a3a3a;
    --game-correct-color: #4CAF50;
    --game-incorrect-color: #D32F2F;
}

body { margin: 0; font-family: var(--font-body); background-color: var(--bg-color); color: var(--text-color); line-height: 1.6; max-width: 100%; overflow-x: hidden; }
.font-container { font-size: 16px; }
.page-container { max-width: clamp(320px, 1200px, 90vw); margin: 0 auto; box-sizing: border-box; }
header { height: auto; min-height: 70px; background-color: var(--card-bg-color); display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; padding: 15px 5vw; margin-bottom: 3em; }
.logo { font-family: var(--font-logo); font-size: clamp(1.8em, 4vw, 2.5em); color: var(--accent-color-2); margin-right: 20px; }
nav a { color: white; text-decoration: none; margin-left: clamp(15px, 3vw, 30px); font-size: clamp(1em, 2.5vw, 1.5em); transition: color 0.3s ease; }
nav a:hover { color: var(--accent-color); }
.chapter-title-card { background-color: var(--card-bg-color); padding: clamp(1em, 3vw, 2em) clamp(1.5em, 4vw, 2.6em); border-radius: 1.5em; margin-bottom: 3em; text-align: center; }
.chapter-title-card h2 { margin: 0; font-size: clamp(1.5em, 4vw, 2.5em); color: var(--accent-color-2); font-weight: 500; }
.collapsible-card { background-color: var(--header-card-bg-color); border-radius: 1.5em; margin-bottom: 25px; overflow: hidden; }
.collapsible-header { display: flex; justify-content: space-between; align-items: center; padding: clamp(1em, 3vw, 1.8em) clamp(1.5em, 4vw, 2.6em); cursor: pointer; background-color: var(--card-bg-color); }
.collapsible-header h3 { margin: 0; font-size: clamp(1.8em, 4.5vw, 2.8em); font-weight: 500; color: var(--text-color-2); }
.toggle-button { background-color: #4a4a4a; border: 1px solid #666; color: white; width: 32px; height: 32px; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 24px; font-weight: bold; cursor: pointer; padding: 0; line-height: 1; transition: background-color 0.3s ease; flex-shrink: 0; }
.toggle-button:hover { background-color: #5a5a5a; }
.collapsible-content-wrapper { max-height: 10000px; opacity: 1; overflow: hidden; transition: max-height 0.7s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.5s ease-out 0.1s; }
.collapsible-content-wrapper.collapsed { max-height: 0; opacity: 0; transition: max-height 0.5s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease-in; }
.collapsible-content-inner { padding: 2em clamp(1.5em, 5vw, 4em); }
.story-image { display: block; width: 100%; max-width: 600px; margin-left: auto; margin-right: auto; height: auto; border-radius: 1em; margin-bottom: 25px; }
.content-block { border-radius: 1em; background-color: #ffffff; padding: clamp(1em, 3vw, 2em); margin-bottom: 25px; position: relative; }
.content-block:last-child { margin-bottom: 0; }
.content-block h4 { font-size: clamp(1.5em, 3.5vw, 2.2em); color: var(--text-color); margin-top: 0; margin-bottom: 0.75em; font-weight: 500; position: relative; padding-bottom: 0.5em; }
.content-block h4::after { content: ''; display: block; width: 100%; height: 1px; background-color: var(--underline-color); position: absolute; bottom: 0; left: 0; }
.story-text-section p { margin-bottom: 10px; font-size: clamp(1em, 2vw, 1.3em); }
.audio-player-section { margin-bottom: 2em !important; }
.audio-controls { display: flex; gap: 15px; margin-bottom: 20px; flex-wrap: wrap; align-items: center; }
.audio-btn { padding: 10px 18px; border: none; border-radius: 25px; font-size: clamp(0.9em, 2vw, 1em); font-weight: 500; cursor: pointer; transition: background-color 0.3s ease, transform 0.1s ease; display: inline-flex; align-items: center; justify-content: center; line-height: 1; }
.audio-btn:active { transform: scale(0.95); }
.play-pause-btn { background-color: var(--accent-color); color: white; padding: 12px; min-width: 50px; height: 50px; border-radius: 50%; display: inline-flex; align-items: center; justify-content: center; line-height: 1; }
.play-pause-btn:hover { background-color: #cc8e11; }
.play-pause-btn svg.icon { width: 24px; height: 24px; }
.play-pause-btn .icon-play { display: inline-block; }
.play-pause-btn .icon-pause { display: none; }
.play-pause-btn.playing .icon-play { display: none; }
.play-pause-btn.playing .icon-pause { display: inline-block; }
.stop-btn { background-color: var(--button-gray); color: var(--text-color-2); padding: 10px 20px; height: 50px; }
.stop-btn:hover { background-color: #505050; }
.audio-progress { display: flex; align-items: center; gap: 12px; margin-bottom: 10px; }
.time-display { font-size: clamp(0.85em, 1.8vw, 1em); color: var(--light-gray); min-width: 40px; text-align: center; }
.progress-bar-container { flex-grow: 1; height: 10px; border-radius: 5px; position: relative; }
#progressBar { -webkit-appearance: none; appearance: none; width: 100%; height: 10px; border-radius: 5px; cursor: pointer; margin: 0; padding: 0; outline: none; background: var(--medium-gray); border: none; display: block; }
#progressBar::-webkit-slider-runnable-track { width: 100%; height: 10px; background: transparent; border: none; border-radius: 5px; }
#progressBar::-webkit-slider-thumb { -webkit-appearance: none; appearance: none; width: 20px; height: 20px; background: var(--accent-color); border-radius: 50%; border: 2px solid var(--card-bg-color); cursor: pointer; margin-top: -5px; box-shadow: 0 1px 3px rgba(0,0,0,0.2); }
#progressBar::-moz-range-track { width: 100%; height: 10px; background: var(--medium-gray); border: none; border-radius: 5px; }
#progressBar::-moz-range-progress { background-color: var(--accent-color); height: 10px; border-radius: 5px; }
#progressBar::-moz-range-thumb { width: 20px; height: 20px; background: var(--accent-color); border-radius: 50%; border: 2px solid var(--card-bg-color); cursor: pointer; box-shadow: 0 1px 3px rgba(0,0,0,0.2); }
.audio-status { font-size: clamp(0.8em, 1.6vw, 0.9em); color: #bebebe; margin: 0; }

/* ----------------------------- ADJECTIVE-SUBJECT RULES SECTION ----------------------------- */

#learn-rules-section .collapsible-content-inner {
    background-color: white;
    padding: 2em clamp(1.5em, 5vw, 4em);
}

.adjektiv-rules-container {
    color: #000;
}

.rules-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 30px;
    margin-bottom: 2.5em;
}
.rules-row:last-child {
    margin-bottom: 0;
}

/* --- Column general styles --- */
.rules-list-col, .rules-text-col {
    flex: 2 1 350px;
}
.rules-image-col {
    flex: 1 1 200px;
    text-align: center;
}
.rules-image-col img {
    max-width: 100%;
    height: auto;
    vertical-align: middle;
}

/* --- Top Row --- */
.top-row .rules-list-col ul {
    list-style: none;
    padding: 0;
    margin: 0;
    font-size: clamp(1.1em, 2.2vw, 1.4em);
    line-height: 1.6;
}
.top-row .rules-list-col li {
    position: relative;
    padding-left: 25px;
    margin-bottom: 1em;
}
.top-row .rules-list-col li::before {
    content: '•';
    position: absolute;
    left: 0;
    font-size: 1.5em;
    color: #000;
    top: 0;
}
.top-row .book-col {
    flex-basis: 250px;
    text-align: right;
}
.top-row .book-col img {
    max-width: 400px;
    width: 350px;
}

/* --- Middle Row --- */
.middle-row {
    gap: 20px;
    margin: 3em 0;
}
.middle-row .illustration-col {
    flex-basis: 350px;
}
.middle-row .large-text-col p {
    font-size: clamp(1.6em, 3.5vw, 2.2em);
    font-weight: 400;
    line-height: 1.4;
    margin: 0;
}

/* --- Bottom Row --- */
.bottom-row {
    align-items: flex-start;
}
.bottom-row .example-col {
    font-size: clamp(1.1em, 2.3vw, 1.4em);
    line-height: 1.8;
}

.bottom-row .example-col h4 {
    font-size: 1.1em;
    font-weight: 700;
    margin: 0 0 0.8em 0;
    text-decoration: underline;
}
.bottom-row .example-col p {
    margin: 0 0 0.3em 0;
}
.bottom-row .example-col .example-statement {
    font-style: italic;
    margin-bottom: 0.8em !important;
}
.bottom-row .example-col em {
    font-style: normal;
    font-style: italic;
}
.bottom-row .question-hint {
    color: #555;
    font-size: 0.9em;
}
.bottom-row .example-box-col {
    flex-basis: 50%;
}

/* ----------------------------- FIND THE SUBJECT GAME STYLES ----------------------------- */


.game-container { 
    text-align: center; 
    padding-bottom: 2em; 
    margin-bottom: 5em; 
}

.game-title { font-size: clamp(2em, 5vw, 3em); color: var(--accent-color); margin-bottom: 0.4em; }
.game-instructions { font-size: clamp(1em, 2.2vw, 1.2em); color: black; margin-bottom: 2em; max-width: 550px; margin-left: auto; margin-right: auto; line-height: 1.5; }
.game-instructions span { color: var(--accent-color); font-weight: 1000; }
.game-area { background-color: #f0f0f0; border-radius: 20px; padding: 30px clamp(15px, 4vw, 40px); box-shadow: inset 0 2px 8px rgba(0,0,0,0.1); }

.sentence-display {
    font-size: clamp(2em, 5vw, 3.5em);
    font-weight: 700;
    color: #333;
    background-color: #fff;
    padding: 20px 30px;
    border-radius: 15px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    margin: 0.5em 0;
    min-height: 1.5em;
}

.game-feedback-display { min-height: 3.5em; display: flex; justify-content: center; align-items: center; perspective: 500px; margin-bottom: 1em; }
.game-feedback-display p { font-size: clamp(1.4em, 3.5vw, 2em); color: var(--text-color-2); font-weight: bold; padding: 12px 25px; border-radius: 12px; box-shadow: 0 4px 10px rgba(0,0,0,0.25); display: inline-block; opacity: 0; transform: translateY(30px) rotateX(-30deg) scale(0.8); transition: opacity 0.6s ease-out, transform 0.6s cubic-bezier(0.175, 0.885, 0.32, 1.275); cursor: default; }
.game-feedback-display p.show { opacity: 1; transform: translateY(0) rotateX(0deg) scale(1); }
.game-feedback-display p.correct { background: linear-gradient(135deg, var(--game-correct-color), #388E3C); }
.game-feedback-display p.incorrect { background: linear-gradient(135deg, var(--game-incorrect-color), #C62828); }

.subject-choices-container { display: flex; justify-content: center; gap: 15px; flex-wrap: wrap; }
.game-choice-btn {
    padding: 12px 25px;
    font-size: clamp(1.1em, 2.8vw, 1.4em);
    font-weight: 500;
    border: 2px solid var(--card-bg-color);
    background-color: white;
    color: var(--card-bg-color);
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.2s ease-in-out;
    box-shadow: 0 3px 6px rgba(0,0,0,0.1);
}
.game-choice-btn:hover:not(:disabled) { background-color: var(--card-bg-color); color: white; transform: translateY(-3px) scale(1.02); }
.game-choice-btn:disabled { opacity: 0.5; cursor: not-allowed; }

@keyframes shake { 10%, 90% { transform: translate3d(-1px, 0, 0); } 20%, 80% { transform: translate3d(2px, 0, 0); } 30%, 50%, 70% { transform: translate3d(-4px, 0, 0); } 40%, 60% { transform: translate3d(4px, 0, 0); } }
.shake { animation: shake 0.7s cubic-bezier(.36,.07,.19,.97) both; }

/* ----------------------------- Mobile Layout Adjustments ----------------------------- */
/* --- Responsive Adjustments for Rules Section --- */
@media (max-width: 850px) {
    .rules-row {
        flex-direction: column;
        gap: 30px;
    }
    .rules-list-col, .rules-text-col, .rules-image-col {
        flex-basis: 100% !important; /* Stack columns */
        width: 100%;
        text-align: center;
    }
    .top-row .rules-list-col, .bottom-row .example-col {
        text-align: left; /* Keep list and example left-aligned */
        align-self: flex-start;
        width: 100%;
    }
    .top-row .book-col {
        text-align: center;
    }
    .middle-row { /* Puts text below the image on mobile */
        flex-direction: column;
    }
}

@media (max-width: 600px) {

    header { 
        flex-direction: column;
        gap: 15px; 
        padding-top: 20px; 
        padding-bottom: 20px; 
    }

    .logo { 
        margin-right: 0;
    }

    nav { 
        display: flex; 
        justify-content: center; 
        gap: 25px; 
        width: 100%; 
    }

    nav a { 
        margin-left: 0; 
    }
}

/* ===================== NEXT CHAPTER BUTTON STYLES ===================== */
.next-chapter-container {
    text-align: center;
    margin: 4em 0 6em 0; /* Adds space above and below the button */
    padding: 0 20px; /* Prevents button from touching screen edges on mobile */
}

.next-chapter-btn {
    display: inline-block;
    background-color: var(--accent-color);
    color: white;
    padding: 16px 35px;
    font-size: clamp(1.1em, 3vw, 1.4em);
    font-weight: 700;
    text-decoration: none;
    border-radius: 50px; /* A pill shape to match other buttons */
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.next-chapter-btn:hover {
    background-color: var(--accent-color-2);
    transform: translateY(-3px) scale(1.03);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.25);
}