.container {
    max-width: 800px;
    margin: 50px auto;
    padding: 20px;
    text-align: center;
}

.word-card {
    border: 1px solid #ccc;
    padding: 40px;
    margin: 20px 0;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    will-change: transform;
}

.hidden {
    filter: blur(5px);
    user-select: none;
}

.revealed {
    filter: none;
    transition: filter 0.3s ease;
}

button {
    padding: 10px 20px;
    margin: 10px;
    border: none;
    border-radius: 4px;
    background-color: #4CAF50;
    color: white;
    cursor: pointer;
}

button:hover {
    background-color: #45a049;
}

.progress-bar {
    cursor: pointer;
    position: relative;
    background-color: #eee;
    border-radius: 10px;
    height: 20px;
    margin: 20px 0;
    overflow: visible;
    user-select: none;
}

#progressFill {
    position: absolute;
    left: 0;
    top: 0;
    height: 100%;
    background-color: #4CAF50;
    border-radius: 10px;
    transition: width 0.1s ease;
}

.progress-handle {
    position: absolute;
    right: -12px;
    top: 50%;
    transform: translateY(-50%);
    width: 24px;
    height: 24px;
    background-color: white;
    border: 2px solid #4CAF50;
    border-radius: 50%;
    cursor: grab;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

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

.progress-tooltip {
    position: absolute;
    top: -30px;
    background-color: #333;
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
    pointer-events: none;
    transform: translateX(-50%);
    opacity: 0;
    transition: opacity 0.2s;
    z-index: 100;
}

.progress-bar:hover .progress-tooltip {
    opacity: 1;
}

.stats {
    display: flex;
    justify-content: space-around;
    margin-bottom: 20px;
}

#playPronunciation {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    padding: 10px;
}

.review-options {
    margin-top: 20px;
}

.main-content {
    display: none;
}

.study-section {
    flex: 2;
}

.history-panel {
    flex: 1;
    padding: 20px;
    border-left: 1px solid #ccc;
    max-height: 80vh;
    overflow-y: auto;
}

.history-item {
    padding: 10px;
    border-bottom: 1px solid #eee;
    text-align: left;
}

.history-item.current {
    background-color: #e8f5e9;
}

.word-english {
    font-weight: bold;
}

.word-translation {
    color: #666;
    font-size: 0.9em;
}

.word-card.wrong-word {
    border-color: #ff6b6b;
    background-color: #fff5f5;
}

.word-details {
    font-size: 0.85em;
    color: #666;
    margin-top: 5px;
    padding-top: 5px;
    border-top: 1px dashed #eee;
}

#translation {
    white-space: pre-line;
    line-height: 1.5;
}

.upload-section {
    text-align: center;
    margin: 20px 0;
    padding: 40px;
    border: 3px dashed #4CAF50;
    border-radius: 8px;
    background-color: #f9f9f9;
}

.upload-box {
    margin: 20px 0;
}

.upload-section h2 {
    color: #333;
    margin-bottom: 20px;
}

.upload-section input[type="file"] {
    display: block;
    margin: 0 auto 20px;
    padding: 10px;
}

.jump-control {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 10px;
    margin: 10px 0;
}

.jump-control input {
    width: 100px;
    padding: 5px 10px;
    border: 1px solid #ccc;
    border-radius: 4px;
    text-align: center;
    font-size: 14px;
}

.jump-control input:focus {
    border-color: #4CAF50;
    outline: none;
}

.jump-control button {
    margin: 0;
    padding: 5px 15px;
}

/* 添加高亮动画效果 */
@keyframes highlight {
    0% {
        transform: scale(1);
        box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    }
    50% {
        transform: scale(1.02);
        box-shadow: 0 4px 8px rgba(0,0,0,0.2);
    }
    100% {
        transform: scale(1);
        box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    }
}

.word-card.highlight {
    animation: highlight 1s ease;
}

.confusing-words-panel {
    margin: 20px 0;
    border-top: 1px solid #eee;
    padding-top: 20px;
}

.confusing-words-input {
    display: flex;
    gap: 10px;
    margin-top: 10px;
    flex-wrap: wrap;
    justify-content: center;
}

.confusing-words-input input {
    padding: 8px 12px;
    border: 1px solid #ccc;
    border-radius: 4px;
    width: 150px;
}

.confusing-words-input button {
    background-color: #2196F3;
}

.confusing-words-input button:hover {
    background-color: #1976D2;
}

details {
    margin: 10px 0;
}

summary {
    cursor: pointer;
    color: #2196F3;
    padding: 5px;
    border-radius: 4px;
}

summary:hover {
    background-color: #e3f2fd;
}