/* --- Local Font Definition --- */
@font-face {
  font-family: 'Noto Sans Limbu';
  font-style: normal;
  font-weight: 400;
  font-display: swap; /* A best practice for performance */
  src: url('fonts/NotoSansLimbu.woff2') format('woff2'); /* Loads the local font file */
}

/* --- Root Variables for Theming --- */
:root {
    --bg-color: #f8f8f8;
    --card-bg: #ffffff;
    --text-color: #333333; 
    --primary-color: #7d4d73; 
    --secondary-color: #707070;
    --border-color: #e0e0e0;
    --highlight-color: #ffe599;
    --header-text-color: #333333;
    --tts-color: #7d4d73;
    --tts-hover-bg: rgba(125, 77, 115, 0.1);
    --btn-hover-bg: rgba(0, 0, 0, 0.05);
}

/* --- Dark Mode Variables --- */
body.dark-mode {
    --bg-color: #1c1c1c;
    --card-bg: #2a2a2a;
    --text-color: #e8e8e8;
    --primary-color: #bfa3b8;
    --secondary-color: #a0a0a0;
    --border-color: #444444;
    --highlight-color: #ffc107;
    --header-text-color: #e8e8e8;
    --tts-color: #bfa3b8;
    --tts-hover-bg: rgba(191, 163, 184, 0.2);
    --btn-hover-bg: rgba(255, 255, 255, 0.1);
}

/* --- General Styles --- */
body {
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
    line-height: 1.6;
    font-family: 'Poppins', Arial, sans-serif;
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 25px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-color);
}

.header-actions {
    display: flex;
    gap: 10px;
}

.letter-header {
    display: flex;
    align-items: center;
    gap: 1em;
    font-size: 2em;
    margin-bottom: 1em;
    color: var(--primary-color);
}
.selected-limbu-letter {
    font-family: 'Noto Sans Limbu', sans-serif;
    font-size: 2.5em;
    font-weight: bold;
}

h1 { 
    color: var(--header-text-color);
    font-size: 2.2em;
    font-weight: 700;
    margin: 0;
    line-height: 1.2;
}

/* --- Controls & Icons --- */
.icon-btn {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--secondary-color);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4em;
    transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

.icon-btn:hover {
    background-color: var(--btn-hover-bg);
    border-color: var(--secondary-color);
    color: var(--primary-color);
}


#controls {
    margin-bottom: 20px;
}

.search-container {
    display: flex;
    align-items: center;
    padding: 10px 15px;
    border: 1px solid var(--border-color);
    border-radius: 25px;
    background-color: var(--card-bg);
    transition: border-color 0.3s;
}

.search-container:focus-within {
    border-color: var(--primary-color);
}

.search-container i {
    color: var(--secondary-color);
    font-size: 1.2em;
    margin-right: 10px;
}

#search-input {
    flex-grow: 1;
    border: none;
    outline: none;
    font-size: 1em;
    background: transparent;
    color: var(--text-color);
}

/* --- Dictionary Entry --- */
.dictionary-entry { 
    border: 1px solid var(--border-color);
    padding: 15px; 
    margin-bottom: 15px; 
    border-radius: 8px;
    background-color: var(--card-bg); 
    box-shadow: 0 1px 3px rgba(0,0,0,0.04);
    transition: background-color 0.3s, box-shadow 0.2s;
    display: flex;
    flex-direction: column;
}

.entry-header {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 8px;
    justify-content: flex-start;
}

.limbu-word { 
    font-size: 1.6em; 
    color: var(--primary-color);
    font-family: 'Noto Sans Limbu', sans-serif;
}

.secondary-info {
    font-size: 1em;
    color: var(--secondary-color);
    font-style: italic;
    font-weight: 400;
}

.meaning-text { 
    margin-top: 8px; 
    color: var(--text-color); 
    white-space: pre-wrap; 
    line-height: 1.5;
}

/* --- TTS Button Styling --- */
.tts-btn {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--tts-color);
    font-size: 1.2em;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s, color 0.2s;
    border-radius: 50%;
    width: 32px;
    height: 32px;
}

.tts-btn:hover {
    background-color: var(--tts-hover-bg);
}

/* --- Highlighting & Loading --- */
.highlight {
    background-color: var(--highlight-color);
    color: black;
    padding: 1px 2px;
    border-radius: 3px;
    font-weight: bold;
}

.loading-message {
    text-align: center;
    padding: 20px;
    font-size: 1.1em;
    color: var(--secondary-color);
}

/* --- Letter Index Styling --- */
.letter-index-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

#letter-index-view h2 {
    color: var(--primary-color);
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 10px;
    margin: 0;
    flex-grow: 1;
}

#letter-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
    gap: 10px;
}

.letter-group-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 5px;
    padding: 15px;
    text-align: center;
    cursor: pointer;
    font-size: 1.5em;
    font-family: 'Noto Sans Limbu', sans-serif;
    font-weight: 700;
    color: var(--primary-color);
    transition: background-color 0.2s, transform 0.1s, box-shadow 0.2s;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.letter-group-card:hover {
    background-color: var(--border-color);
    transform: translateY(-2px);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

body.dark-mode .letter-group-card:hover {
    background-color: #37475a;
}

/* --- Responsive Adjustments --- */
@media screen and (max-width: 600px) {
    body {
        padding: 15px 12px;
    }
    
    h1 {
        font-size: 1.75em; 
    }
    
    header {
        margin-bottom: 15px;
    }
    
    #controls {
        margin-bottom: 15px;
    }

    .entry-header {
        flex-direction: row;
        flex-wrap: wrap;
        gap: 5px;
    }

    .limbu-word {
        font-size: 1.4em;
    }

    .tts-btn {
        width: 28px;
        height: 28px;
        font-size: 1em;
    }

    .secondary-info {
        font-size: 0.9em;
    }
}

/* --- Scroll to Top Button --- */
#scroll-to-top-btn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 1000; /* Ensures it's on top of other content */
    
    /* Initially hidden */
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: opacity 0.3s ease-in-out, visibility 0.3s ease-in-out, transform 0.3s ease-in-out;
}

#scroll-to-top-btn.show {
    /* Class added by JS to show the button */
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}