/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: #1f2a24;
    background-color: #f4f7f5;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 头部 */
header {
    background: linear-gradient(135deg, #0f766e 0%, #15803d 100%);
    color: white;
    padding: 2.2rem 0;
    text-align: center;
}

header h1 {
    font-size: 2.3rem;
    margin-bottom: 0.5rem;
    font-weight: 700;
}

.subtitle {
    font-size: 1.05rem;
    opacity: 0.92;
}

/* 面包屑 */
.breadcrumb {
    background: #e8f2ee;
    border-bottom: 1px solid #d4e7df;
    font-size: 0.9rem;
    color: #4a5a52;
}
.breadcrumb .container {
    padding-top: 0.7rem;
    padding-bottom: 0.7rem;
}
.breadcrumb a {
    color: #0f766e;
    text-decoration: none;
}
.breadcrumb a:hover { text-decoration: underline; }

/* 主体 */
main {
    padding: 2rem 0;
}

.card {
    background: white;
    border-radius: 12px;
    padding: 1.8rem;
    box-shadow: 0 4px 20px rgba(15, 118, 110, 0.08);
    margin-bottom: 1.6rem;
}

.card h2 {
    color: #0f766e;
    margin-bottom: 1.3rem;
    font-size: 1.5rem;
    border-bottom: 2px solid #0f766e;
    padding-bottom: 0.5rem;
}

/* 表单 */
.calculator-form {
    max-width: 720px;
}

.form-row {
    display: flex;
    gap: 1.2rem;
    flex-wrap: wrap;
}

.form-group {
    flex: 1 1 240px;
    margin-bottom: 1.2rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #3a4a42;
}

.form-group input {
    width: 100%;
    padding: 0.7rem 0.8rem;
    border: 2px solid #d4e7df;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.form-group input:focus {
    outline: none;
    border-color: #0f766e;
    box-shadow: 0 0 0 3px rgba(15, 118, 110, 0.12);
}

.calc-btn {
    background: linear-gradient(135deg, #0f766e 0%, #15803d 100%);
    color: white;
    border: none;
    padding: 0.9rem 2.2rem;
    border-radius: 8px;
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    margin-top: 0.4rem;
}

.calc-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(15, 118, 110, 0.3);
}

.hint {
    margin-top: 1rem;
    font-size: 0.85rem;
    color: #6b7a72;
    background: #f0f7f4;
    border-left: 3px solid #0f766e;
    padding: 0.7rem 1rem;
    border-radius: 0 6px 6px 0;
}

/* 结果 */
.result.hidden { display: none; }

.result-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 0.8rem;
}

.result-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.8rem 1rem;
    background: #f4f9f7;
    border-radius: 8px;
    border-left: 3px solid #0f766e;
}

.result-item.highlight {
    background: #e8f2ee;
    border-left-color: #15803d;
    font-weight: 600;
}

.result-label {
    color: #4a5a52;
    font-size: 0.95rem;
}

.result-value {
    font-weight: 700;
    color: #0f766e;
    font-size: 1.05rem;
}

/* 参考表 */
.ref-tables {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.4rem;
}

.ref-table h3 {
    color: #0f766e;
    margin-bottom: 0.8rem;
    font-size: 1.15rem;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.92rem;
}

table th, table td {
    padding: 0.6rem 0.7rem;
    text-align: left;
    border-bottom: 1px solid #e3efe7;
}

table th {
    background: #f0f7f4;
    font-weight: 600;
    color: #0f766e;
}

table tr:hover { background: #f7fbf9; }

.cta {
    margin-top: 1.3rem;
    padding: 0.9rem 1.1rem;
    background: #e8f2ee;
    border-radius: 8px;
    font-size: 0.98rem;
}
.cta a { color: #0f766e; font-weight: 600; }

/* 底部 */
footer {
    background: #0f3d22;
    color: #cfe7d6;
    text-align: center;
    padding: 1.8rem 0;
    margin-top: 2rem;
    font-size: 0.9rem;
}
footer a { color: #9be7b4; }

/* 响应式 */
@media (max-width: 768px) {
    .container { padding: 0 15px; }
    header h1 { font-size: 1.8rem; }
    .card { padding: 1.3rem; }
    .form-row { gap: 0; }
    .form-group { flex: 1 1 100%; }
    table { font-size: 0.85rem; }
}