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

:root {
    --primary: #4a90d9;
    --primary-light: #e8f1fb;
    --primary-lighter: #f4f8fd;
    --text: #2c3e50;
    --text-light: #7f8c9b;
    --border: #c5d8ec;
    --white: #ffffff;
    --hover: #3a7bc8;
    --success-bg: #d4edda;
    --success-text: #155724;
    --success-border: #c3e6cb;
    --error-bg: #fdf0ef;
    --error-text: #d9534f;
    --error-border: #f5c6cb;
}

body {
    font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
    background-color: var(--primary-lighter);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 20px;
}

/* ===== 头部 ===== */
header {
    text-align: center;
    padding: 30px 0 20px;
}

header h1 {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 8px;
}

header .subtitle {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* ===== 卡片 ===== */
.card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 20px;
    margin-bottom: 20px;
}

.card h2 {
    font-size: 1.1rem;
    color: var(--primary);
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--primary-light);
}

/* ===== 输入区 ===== */
.input-group {
    margin-bottom: 15px;
}

.input-group label {
    display: block;
    font-size: 0.9rem;
    color: var(--text-light);
    margin-bottom: 5px;
}

textarea,
input[type="number"] {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-family: "Consolas", "Courier New", monospace;
    font-size: 0.95rem;
    resize: vertical;
    background: var(--white);
    color: var(--text);
    transition: border-color 0.2s;
}

textarea:focus,
input[type="number"]:focus {
    outline: none;
    border-color: var(--primary);
}

textarea[readonly] {
    background: var(--primary-lighter);
}

select {
    width: 100%;
    padding: 8px 10px;
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.95rem;
    background: var(--white);
    color: var(--text);
    cursor: pointer;
}

select:focus {
    outline: none;
    border-color: var(--primary);
}

.hint-text {
    font-size: 0.85rem;
    color: var(--text-light);
    margin-top: -5px;
}

/* ===== 按钮 ===== */
.btn-group {
    display: flex;
    gap: 10px;
    margin-top: 10px;
    flex-wrap: wrap;
}

.btn-primary,
.btn-secondary {
    padding: 10px 25px;
    border: none;
    border-radius: 6px;
    font-size: 0.95rem;
    cursor: pointer;
    transition: background-color 0.2s;
}

.btn-primary {
    background: var(--primary);
    color: var(--white);
    flex: 1;
}

.btn-primary:hover {
    background: var(--hover);
}

.btn-secondary {
    background: var(--primary-light);
    color: var(--primary);
}

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

/* ===== 输出区 ===== */
.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.result-label {
    font-size: 0.9rem;
    color: var(--text-light);
    font-weight: 600;
}

.copy-btn {
    padding: 5px 15px;
    border: 1px solid var(--border);
    border-radius: 4px;
    background: var(--primary-light);
    color: var(--primary);
    font-size: 0.85rem;
    cursor: pointer;
    transition: background-color 0.2s;
}

.copy-btn:hover {
    background: var(--border);
}

.copy-btn.copied {
    background: var(--success-bg);
    color: var(--success-text);
    border-color: var(--success-border);
}

/* ===== 错误提示 ===== */
.error-msg {
    color: var(--error-text);
    background: var(--error-bg);
    border: 1px solid var(--error-border);
    border-radius: 6px;
    padding: 10px 15px;
    margin-bottom: 15px;
    font-size: 0.9rem;
}

/* ===== 响应式 ===== */
@media (max-width: 600px) {
    .container {
        padding: 10px;
    }

    header h1 {
        font-size: 1.5rem;
    }

    .btn-group {
        flex-direction: column;
    }

    .btn-primary,
    .btn-secondary {
        width: 100%;
        flex: none;
    }
}