/**
 * Reading Themes & Sentence Highlighting Design System
 * 
 * 4 Calibrated Themes:
 * - Light (Cream paper #fdfcf7, dark charcoal text)
 * - Sepia (Warm parchment #f4ecd8, deep espresso text)
 * - Dark (Slate #1e242b, muted ivory text)
 * - OLED Night (Absolute black #000000, silver-white text)
 */

:root {
    --transition-speed: 0.2s;
    background-color: #191d24;
}

/* Light Theme (Cream Paper) */
body.theme-light {
    --bg-primary: #fdfcf7;
    --bg-secondary: #f4f1ea;
    --bg-card: #ffffff;
    --text-primary: #23211e;
    --text-secondary: #635f59;
    --border-color: #e5e0d8;
    --accent-color: #b45309;
    --accent-hover: #92400e;
    --dock-bg: rgba(255, 255, 255, 0.95);
    --dock-border: #e2ddd3;
    
    /* Sentence Highlighting */
    --tts-highlight-bg: #fef08a; /* Soft buttercup yellow */
    --tts-highlight-text: #1a1714;
    --tts-highlight-border: #facc15;
}

/* Sepia Theme (Warm Parchment) */
body.theme-sepia {
    --bg-primary: #f5eedc;
    --bg-secondary: #ebdcb9;
    --bg-card: #fbf6ec;
    --text-primary: #3d2f23;
    --text-secondary: #745f4d;
    --border-color: #dfcdad;
    --accent-color: #8c4c1e;
    --accent-hover: #703c16;
    --dock-bg: rgba(245, 238, 220, 0.96);
    --dock-border: #dac59f;

    /* Sentence Highlighting */
    --tts-highlight-bg: #fed7aa; /* Warm amber peach */
    --tts-highlight-text: #2c1a0e;
    --tts-highlight-border: #f97316;
}

/* Dark Theme (Slate) */
body.theme-dark {
    --bg-primary: #191d24;
    --bg-secondary: #232832;
    --bg-card: #20252e;
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --border-color: #30363d;
    --accent-color: #38bdf8;
    --accent-hover: #0284c7;
    --dock-bg: rgba(25, 29, 36, 0.95);
    --dock-border: #30363d;

    /* Sentence Highlighting */
    --tts-highlight-bg: #854d0e; /* Deep warm amber */
    --tts-highlight-text: #fef08a;
    --tts-highlight-border: #eab308;
}

/* OLED Night Theme (Pure Black) */
body.theme-oled {
    --bg-primary: #000000;
    --bg-secondary: #121212;
    --bg-card: #0d0d0d;
    --text-primary: #ededed;
    --text-secondary: #7a7a7a;
    --border-color: #262626;
    --accent-color: #f59e0b;
    --accent-hover: #d97706;
    --dock-bg: rgba(0, 0, 0, 0.98);
    --dock-border: #262626;

    /* Sentence Highlighting */
    --tts-highlight-bg: #78350f; /* High-contrast golden glow */
    --tts-highlight-text: #fef9c3;
    --tts-highlight-border: #f59e0b;
}

/* Base Body Application */
body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color var(--transition-speed) ease, color var(--transition-speed) ease;
}

/* Sentence Highlighting Styles */
.tts-sentence {
    position: relative;
    border-radius: 3px;
    padding: 2px 0;
    cursor: pointer;
    box-decoration-break: clone;
    -webkit-box-decoration-break: clone;
    transition: background-color 0.15s ease;
}

.tts-sentence:hover {
    background-color: rgba(234, 179, 8, 0.15);
    border-radius: 3px;
}

.tts-sentence.tts-active {
    background-color: var(--tts-highlight-bg) !important;
    color: var(--tts-highlight-text) !important;
    border-radius: 3px;
    padding: 2px 0;
    box-decoration-break: clone;
    -webkit-box-decoration-break: clone;
    box-shadow: none;
    font-weight: 500;
}

/* Chapter Reading Mode Highlighting */
.reader-mode-chapter .reader-chapter-content.tts-active {
    background-color: var(--tts-highlight-bg) !important;
    color: var(--tts-highlight-text) !important;
    border-radius: 8px;
    padding: 20px;
    transition: background-color 0.2s ease, color 0.2s ease;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.reader-mode-chapter .reader-chapter-content.tts-active p,
.reader-mode-chapter .reader-chapter-content.tts-active h1,
.reader-mode-chapter .reader-chapter-content.tts-active h2,
.reader-mode-chapter .reader-chapter-content.tts-active h3,
.reader-mode-chapter .reader-chapter-content.tts-active span {
    color: var(--tts-highlight-text) !important;
}

.reader-mode-chapter .tts-sentence {
    cursor: default;
    background-color: transparent !important;
}

.reader-mode-chapter .tts-sentence:hover {
    background-color: transparent !important;
}

/* Chapter Reading Mode Active Container Highlight */
.reader-chapter-content.tts-chapter-active {
    background-color: var(--tts-highlight-bg);
    color: var(--tts-highlight-text);
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 0 0 1px var(--tts-highlight-border);
    transition: background-color 0.25s ease;
}