/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f5f5;
    color: #333;
    line-height: 1.6;
    padding: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

/* 容器 - 经典计算器外壳 */
.container {
    max-width: 400px;
    width: 100%;
    background-color: #fff;
    border: 2px solid #333;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    overflow: hidden;
}

/* 标题区域 */
.header {
    background-color: #333;
    color: #fff;
    padding: 20px;
    text-align: center;
    border-bottom: 2px solid #222;
}

.header h1 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 5px;
}

.subtitle {
    font-size: 12px;
    color: #ccc;
}

/* 主要内容区域 */
.main-content {
    padding: 25px;
}

/* 输入区域 */
.input-section {
    margin-bottom: 0;
}

/* 表单组 */
.form-group {
    margin-bottom: 18px;
}

.form-label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 8px;
    color: #555;
}

/* 单选按钮组 */
.radio-group {
    display: flex;
    gap: 15px;
}

.radio-label {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-size: 14px;
}

.radio-label input[type="radio"] {
    margin-right: 5px;
    cursor: pointer;
}

.radio-text {
    user-select: none;
}

/* 输入框包装 */
.input-wrapper {
    display: flex;
    align-items: center;
    gap: 8px;
}

.number-input {
    flex: 1;
    padding: 10px 12px;
    font-size: 16px;
    border: 2px solid #ddd;
    border-radius: 4px;
    outline: none;
    transition: border-color 0.2s;
}

.number-input:focus {
    border-color: #333;
}

.number-input::placeholder {
    color: #aaa;
}

.input-unit {
    font-size: 14px;
    font-weight: 500;
    color: #666;
    min-width: 50px;
}

/* 按钮组 */
.button-group {
    margin-top: 20px;
    text-align: center;
}

.btn {
    padding: 12px 40px;
    font-size: 16px;
    font-weight: 500;
    border: 2px solid #333;
    border-radius: 4px;
    background-color: #333;
    color: #fff;
    cursor: pointer;
    transition: all 0.2s;
}

.btn:hover {
    background-color: #555;
    border-color: #555;
}

.btn:active {
    transform: translateY(1px);
}

/* 分隔线 */
.divider {
    height: 2px;
    background-color: #e0e0e0;
    margin: 25px 0;
}

/* 结果区域 */
.result-section {
    margin-top: 0;
}

.section-title {
    font-size: 14px;
    font-weight: 500;
    color: #555;
    margin-bottom: 15px;
    text-align: center;
}

/* 结果显示 */
.result-display {
    background-color: #f9f9f9;
    border: 2px solid #ddd;
    border-radius: 4px;
    padding: 20px;
    text-align: center;
    margin-bottom: 15px;
}

.result-label {
    font-size: 14px;
    color: #666;
    margin-bottom: 10px;
}

.result-value {
    font-size: 36px;
    font-weight: 700;
    color: #333;
}

.result-value #wind-chill-value {
    letter-spacing: 1px;
}

.result-unit {
    font-size: 24px;
    font-weight: 400;
    color: #666;
    margin-left: 5px;
}

/* 提示信息 */
.info-text {
    font-size: 12px;
    color: #666;
    text-align: center;
    padding: 10px;
    background-color: #fffbf0;
    border: 1px solid #ffe4a0;
    border-radius: 4px;
    line-height: 1.5;
}

/* 消息框 */
.message-box {
    margin-top: 15px;
    padding: 12px;
    border-radius: 4px;
    display: flex;
    align-items: center;
    gap: 10px;
    position: relative;
    font-size: 13px;
}

.message-box.error {
    background-color: #fee;
    border: 1px solid #fcc;
    color: #c33;
}

.message-box.warning {
    background-color: #ffc;
    border: 1px solid #fc0;
    color: #963;
}

.message-box.success {
    background-color: #efe;
    border: 1px solid #cfc;
    color: #3a3;
}

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

.message-text {
    flex: 1;
}

.message-close {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    color: inherit;
    padding: 0;
    width: 20px;
    height: 20px;
    line-height: 1;
}

.message-close:hover {
    opacity: 0.7;
}

/* 响应式设计 */
@media (max-width: 480px) {
    body {
        padding: 10px;
    }

    .container {
        border-radius: 4px;
    }

    .main-content {
        padding: 20px;
    }

    .header h1 {
        font-size: 18px;
    }

    .result-value {
        font-size: 28px;
    }

    .result-unit {
        font-size: 18px;
    }

    .radio-group {
        flex-direction: column;
        gap: 10px;
    }
}