* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --text-primary: #333333;
    --text-secondary: #666666;
    --accent-color: #4CAF50;
    --accent-hover: #45a049;
    --border-color: #ddd;
    --shadow: rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --text-primary: #e0e0e0;
    --text-secondary: #b0b0b0;
    --accent-color: #66bb6a;
    --accent-hover: #81c784;
    --border-color: #444;
    --shadow: rgba(0, 0, 0, 0.3);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    transition: background-color 0.3s, color 0.3s;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    background-color: var(--bg-secondary);
    border-radius: 20px;
    padding: 30px;
    max-width: 700px;
    width: 100%;
    box-shadow: 0 10px 30px var(--shadow);
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}

h1 {
    font-size: 1.8em;
    color: var(--text-primary);
}

.theme-btn {
    background: none;
    border: 2px solid var(--border-color);
    border-radius: 50%;
    width: 45px;
    height: 45px;
    font-size: 1.5em;
    cursor: pointer;
    transition: transform 0.3s;
}

.theme-btn:hover {
    transform: rotate(20deg);
}

.pdf-section {
    margin-bottom: 25px;
}

.pdf-info {
    margin-top: 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px;
    background-color: var(--bg-primary);
    border-radius: 10px;
    font-size: 0.9em;
    color: var(--text-secondary);
}

.btn {
    padding: 12px 24px;
    border: none;
    border-radius: 10px;
    font-size: 1em;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 600;
}

.btn-primary {
    background-color: var(--accent-color);
    color: white;
    width: 100%;
}

.btn-primary:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px var(--shadow);
}

.btn-secondary {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    width: 100%;
}

.btn-secondary:hover {
    background-color: var(--accent-color);
    color: white;
    border-color: var(--accent-color);
}

.btn-small {
    padding: 6px 12px;
    font-size: 0.85em;
    background-color: var(--bg-primary);
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.controls-section {
    margin-bottom: 25px;
}

.voice-controls {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 20px;
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.control-group label {
    font-size: 0.9em;
    font-weight: 600;
    color: var(--text-secondary);
}

select {
    padding: 10px;
    border-radius: 8px;
    border: 2px solid var(--border-color);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1em;
    cursor: pointer;
}

.progress-section {
    margin-bottom: 20px;
}

.progress-bar {
    position: relative;
    height: 8px;
    background-color: var(--border-color);
    border-radius: 10px;
    cursor: pointer;
    margin-bottom: 10px;
}

.progress-fill {
    height: 100%;
    background-color: var(--accent-color);
    border-radius: 10px;
    width: 0%;
    transition: width 0.3s;
}

.progress-handle {
    position: absolute;
    top: 50%;
    transform: translate(-50%, -50%);
    width: 16px;
    height: 16px;
    background-color: var(--accent-color);
    border-radius: 50%;
    cursor: grab;
    left: 0%;
    box-shadow: 0 2px 5px var(--shadow);
}

.progress-handle:active {
    cursor: grabbing;
}

.time-display {
    display: flex;
    justify-content: space-between;
    font-size: 0.85em;
    color: var(--text-secondary);
}

.playback-controls {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 20px;
}

.btn-control {
    width: 60px;
    height: 60px;
    font-size: 1.5em;
    border-radius: 50%;
    background-color: var(--bg-primary);
    border: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-play {
    width: 80px;
    height: 80px;
    font-size: 2em;
    background-color: var(--accent-color);
    color: white;
    border: none;
}

.btn-play:hover:not(:disabled) {
    background-color: var(--accent-hover);
    transform: scale(1.1);
}

.export-section {
    margin-top: 20px;
}

#export-progress {
    margin-top: 15px;
    text-align: center;
}

#export-progressbar {
    width: 100%;
    height: 25px;
    border-radius: 10px;
}

#export-status {
    display: block;
    margin-top: 8px;
    font-size: 0.9em;
    color: var(--text-secondary);
}

.status {
    text-align: center;
    padding: 15px;
    background-color: var(--bg-primary);
    border-radius: 10px;
    margin-bottom: 15px;
    font-weight: 500;
}

.cache-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85em;
    color: var(--text-secondary);
}

.hidden {
    display: none !important;
}

@media (max-width: 600px) {
    .container {
        padding: 20px;
    }

    h1 {
        font-size: 1.4em;
    }

    .voice-controls {
        grid-template-columns: 1fr;
    }
}