/* 黑白灰主题 CSS */

/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
    min-height: 100vh;
    position: relative;
}

/* 主题切换按钮 */
.theme-switcher {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
}

.theme-toggle-btn {
    background: linear-gradient(135deg, #2c3e50, #34495e);
    color: white;
    border: none;
    padding: 10px 15px;
    border-radius: 25px;
    cursor: pointer;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    transition: all 0.3s ease;
}

.theme-toggle-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.theme-icon {
    font-size: 16px;
}

.theme-text {
    font-weight: 500;
}

/* 主容器 */
.container {
    max-width: 800px;
    margin: 80px auto 20px;
    padding: 20px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

/* 标签页区域 */
.tabs {
    display: flex;
    background: #f8f9fa;
    border-radius: 10px;
    padding: 5px;
    margin-bottom: 30px;
    box-shadow: inset 0 2px 5px rgba(0, 0, 0, 0.1);
}

.tabs input[type="radio"] {
    display: none;
}

.tab {
    flex: 1;
    padding: 12px 15px;
    text-align: center;
    background: transparent;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: #666;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.tab:hover {
    background: rgba(0, 0, 0, 0.05);
    color: #333;
}

.tabs input[type="radio"]:checked + .tab {
    background: #2c3e50;
    color: white;
    box-shadow: 0 2px 8px rgba(44, 62, 80, 0.3);
}

/* 输入表单区域 */
.input-section {
    background: #fafafa;
    padding: 25px;
    border-radius: 12px;
    margin-bottom: 30px;
    border: 1px solid #e9ecef;
}

.input-section h2 {
    color: #2c3e50;
    margin-bottom: 20px;
    font-size: 20px;
    font-weight: 600;
    text-align: center;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: #495057;
    font-weight: 500;
    font-size: 14px;
}

.form-group input {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid #e9ecef;
    border-radius: 8px;
    font-size: 14px;
    transition: all 0.3s ease;
    background: white;
}

.form-group input:focus {
    outline: none;
    border-color: #2c3e50;
    box-shadow: 0 0 0 3px rgba(44, 62, 80, 0.1);
}

.form-group input::placeholder {
    color: #adb5bd;
}

/* 按钮组 */
.button-group {
    display: flex;
    gap: 15px;
    margin-top: 25px;
}

.button-group button {
    flex: 1;
    padding: 12px 20px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

#startBtn {
    background: linear-gradient(135deg, #2c3e50, #34495e);
    color: white;
}

#startBtn:hover {
    background: linear-gradient(135deg, #34495e, #2c3e50);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(44, 62, 80, 0.3);
}

#stopBtn {
    background: linear-gradient(135deg, #6c757d, #495057);
    color: white;
}

#stopBtn:hover {
    background: linear-gradient(135deg, #495057, #6c757d);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(108, 117, 125, 0.3);
}

/* 倒计时显示区域 */
.countdown-section {
    background: #2c3e50;
    padding: 30px;
    border-radius: 12px;
    text-align: center;
    color: white;
}

.countdown-section h2 {
    margin-bottom: 25px;
    font-size: 18px;
    font-weight: 500;
    color: #ecf0f1;
}

.countdown-display {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.countdown-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    min-width: 80px;
}

.number {
    font-size: 2.5rem;
    font-weight: 700;
    color: #ecf0f1;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    margin-bottom: 5px;
    font-family: 'Courier New', monospace;
}

.label {
    font-size: 14px;
    color: #bdc3c7;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        margin: 70px 15px 20px;
        padding: 15px;
    }
    
    .tabs {
        flex-direction: column;
        gap: 5px;
    }
    
    .tab {
        padding: 10px;
    }
    
    .countdown-display {
        gap: 15px;
    }
    
    .countdown-item {
        min-width: 60px;
    }
    
    .number {
        font-size: 2rem;
    }
    
    .button-group {
        flex-direction: column;
    }
    
    .theme-switcher {
        top: 10px;
        right: 10px;
    }
    
    .theme-toggle-btn {
        padding: 8px 12px;
        font-size: 12px;
    }
}

@media (max-width: 480px) {
    .countdown-display {
        gap: 10px;
    }
    
    .countdown-item {
        min-width: 50px;
    }
    
    .number {
        font-size: 1.5rem;
    }
    
    .label {
        font-size: 12px;
    }
}