.tool-container {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
    background: white;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.instruction {
    margin-bottom: 25px;
    color: #555;
    font-size: 0.95rem;
}

.instruction ul {
    margin: 10px 0;
    padding-left: 20px;
}

.instruction code {
    background: #f0f0f0;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
    color: #d35400;
}

/* 快捷筛选按钮组 */
.quick-filters {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 15px;
    justify-content: center;
}


/* 统一按钮样式 */
.filter-btn {
    padding: 8px 16px;
    background: #3498db;
    color: white;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.filter-btn:hover {
    background: #2980b9;
    transform: translateY(-1px);
}

.filter-btn:active {
    transform: translateY(0);
}

/* 可选：为两行添加轻微视觉区分 */
.quick-filters:nth-child(2) {
    margin-top: 10px;
    padding-top: 15px;
    border-top: 1px dashed #ddd;
}

.input-group {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

#relation-input {
    flex: 1;
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 1rem;
    outline: none;
}

#relation-input:focus {
    border-color: #3498db;
}

#calculate-btn {
    padding: 0 20px;
    background: #8e44ad;
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: bold;
    white-space: nowrap;
}

#calculate-btn:hover {
    background: #7d3c98;
}

.result {
    min-height: 80px;
    padding: 15px;
    background: #f8f9fa;
    border: 2px dashed #bdc3c7;
    border-radius: 8px;
    font-size: 1rem;
    color: #2c3e50;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    cursor: pointer;
    transition: all 0.3s ease;
}

.result:hover {
    background: #e8f4fc;
    border-color: #3498db;
    transform: scale(1.02);
}

.result.success {
    background: #d4edda;
    border-color: #c3e6cb;
    color: #155724;
}

.result.success .result-main {
    font-weight: bold;
    font-size: 1.1rem;
}

.result.success .cn {
    color: #c0392b;
    font-size: 1.2em;
}

.result.success .en {
    color: #2980b9;
    font-style: italic;
}

.result.success .ipa {
    color: #7f8c8d;
    font-family: monospace;
    font-size: 0.9em;
    margin-top: 5px;
}

.result.success .pronounce-hint {
    font-size: 0.8em;
    color: #34495e;
    margin-top: 5px;
    opacity: 0.7;
}

.result.error {
    background: #f8d7da;
    border-color: #f5c6cb;
    color: #721c24;
}
/* 发音状态反馈 */
.result.speaking {
    background: #d1ecf1;
    border-color: #0c5460;
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.03); }
    100% { transform: scale(1); }
}