/* ============================================================
   电子学计算器 - Fashionistas 主题同款样式
   配色/字体对齐 dalaotech.com 的 WordPress 主题 Fashionistas 1.9
   ============================================================ */

:root {
  --bg: #fff;
  --text: #333;
  --muted: #666;
  --accent: #1fa0ae;        /* Fashionistas 特色青蓝 */
  --accent-dark: #178893;
  --border: #e6e6e6;
  --border-strong: #333;
  --card-bg: #fff;
  --font-body: Georgia, "Times New Roman", Times, serif;
  --font-head: "Oswald", Arial, Helvetica, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
}

a {
  color: var(--accent);
  text-decoration: none;
}
a:hover { color: var(--accent-dark); text-decoration: underline; }

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-head);
  color: var(--text);
  font-weight: 500;
  letter-spacing: .3px;
}

code {
  font-family: "Courier New", Consolas, monospace;
  background: #f4f8f9;
  color: var(--accent-dark);
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 14px;
}

/* ============ WordPress 风格页头 ============ */
.wp-header {
  border-bottom: 1px solid var(--border);
  background: #fff;
}
.wp-header-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 28px 20px 14px;
  text-align: center;
}
.wp-site-title {
  font-family: var(--font-head);
  font-size: 34px;
  font-weight: 600;
  letter-spacing: 1px;
  color: var(--text);
  text-transform: uppercase;
}
.wp-site-title:hover { color: var(--text); text-decoration: none; }
.wp-tagline {
  display: block;
  font-family: var(--font-body);
  font-style: italic;
  color: var(--muted);
  font-size: 14px;
  margin-top: 4px;
}

.wp-nav {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 20px;
  border-top: 3px solid var(--border-strong);
  border-bottom: 1px solid var(--border);
}
.wp-nav a {
  font-family: var(--font-head);
  font-size: 15px;
  letter-spacing: .5px;
  text-transform: uppercase;
  color: var(--text);
  display: inline-block;
  padding: 14px 18px 14px 0;
  margin-right: 4px;
}
.wp-nav a:hover { color: var(--accent); text-decoration: none; }
.wp-nav a.current { color: var(--accent); }

/* ============ 布局容器 ============ */
.container {
  max-width: 980px;
  margin: 0 auto;
  padding: 30px 20px 50px;
}

.page-header { margin-bottom: 26px; }
.page-header h1 {
  font-size: 30px;
  margin: 0 0 8px;
}
.page-header p {
  color: var(--muted);
  margin: 0;
  font-size: 16px;
}

/* ============ 卡片 ============ */
.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 22px 24px;
  margin-bottom: 24px;
}
.card-title {
  font-family: var(--font-head);
  font-size: 18px;
  text-transform: uppercase;
  letter-spacing: .5px;
  color: var(--text);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 8px;
  margin-bottom: 18px;
}
.muted-sub {
  font-family: var(--font-body);
  text-transform: none;
  letter-spacing: 0;
  font-size: 13px;
  color: var(--muted);
  float: right;
  font-weight: 400;
}

/* ============ 工具合集网格 ============ */
.calc-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  margin-top: 10px;
}
.calc-card {
  display: block;
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 24px 22px;
  transition: border-color .15s, transform .15s;
}
.calc-card:hover {
  border-color: var(--accent);
  text-decoration: none;
  transform: translateY(-2px);
}
.calc-card h3 {
  font-size: 19px;
  margin: 14px 0 8px;
}
.calc-card p {
  color: var(--muted);
  font-size: 14.5px;
  margin: 0 0 14px;
  min-height: 64px;
}
.card-icon {
  width: 52px; height: 52px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 24px;
  font-family: var(--font-head);
}
.arrow {
  font-family: var(--font-head);
  color: var(--accent);
  font-size: 14px;
  letter-spacing: .5px;
}

/* ============ 表单 ============ */
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px 22px;
}
.form-group { display: flex; flex-direction: column; }
.form-group.full { grid-column: 1 / -1; }
.form-group label {
  font-family: var(--font-head);
  font-size: 13px;
  letter-spacing: .5px;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 6px;
}
.input-row { display: flex; gap: 8px; }
.input-row input {
  flex: 1;
  min-width: 0;
}
input[type="number"], select, input[type="text"] {
  font-family: var(--font-body);
  font-size: 15px;
  color: var(--text);
  background: #fff;
  border: 1px solid #ccc;
  border-radius: 3px;
  padding: 9px 10px;
}
input[type="number"]:focus, select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(31,160,174,.15);
}
select {
  background: #fff;
  cursor: pointer;
}
select.standalone {
  width: 100%;
  max-width: 320px;
}

.radio-group {
  display: flex;
  gap: 22px;
  flex-wrap: wrap;
  align-items: center;
}
.radio-group label {
  font-family: var(--font-body);
  text-transform: none;
  letter-spacing: 0;
  color: var(--text);
  font-size: 15px;
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
}
.radio-group input { width: auto; }

/* ============ 按钮 ============ */
.btn-row { margin-top: 20px; display: flex; gap: 12px; }
.btn {
  font-family: var(--font-head);
  font-size: 15px;
  letter-spacing: .5px;
  text-transform: uppercase;
  padding: 11px 22px;
  border: none;
  border-radius: 3px;
  cursor: pointer;
  transition: background .15s;
}
.btn-primary {
  background: var(--accent);
  color: #fff;
  border-bottom: 3px solid var(--accent-dark);
}
.btn-primary:hover { background: var(--accent-dark); }
.btn-secondary {
  background: #333;
  color: #fff;
  border-bottom: 3px solid #666;
}
.btn-secondary:hover { background: #666; }

/* ============ 结果区 ============ */
.result-box {
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 6px 18px;
  background: #fcfdfd;
}
.result-item {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 11px 0;
  border-bottom: 1px dashed var(--border);
  gap: 16px;
}
.result-item:last-child { border-bottom: none; }
.result-label {
  font-family: var(--font-body);
  color: var(--muted);
  font-size: 15px;
}
.result-value {
  font-family: var(--font-head);
  color: var(--text);
  font-size: 17px;
  text-align: right;
  font-weight: 500;
}
.result-value .unit {
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--muted);
  font-weight: 400;
}

/* ============ 图表 ============ */
.chart-container {
  margin-top: 20px;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 10px;
  background: #fafbfc;
}
.chart-container canvas { width: 100%; height: 220px; display: block; }

/* ============ 公式说明 ============ */
.formula-note {
  margin-top: 20px;
  padding: 16px 18px;
  background: #f4f8f9;
  border-left: 4px solid var(--accent);
  border-radius: 0 4px 4px 0;
  font-size: 14.5px;
  color: #455a64;
  line-height: 1.8;
}

/* ============ 页脚 ============ */
.footer {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 22px 20px;
  color: var(--muted);
  font-size: 13.5px;
  font-family: var(--font-body);
}
.footer a { color: var(--accent); }

/* ============ 提示条 ============ */
.hint {
  margin-top: 14px;
  font-size: 13.5px;
  color: var(--muted);
  background: #f4f8f9;
  border-left: 3px solid var(--accent);
  padding: 10px 12px;
  border-radius: 0 4px 4px 0;
  line-height: 1.7;
}
.hint code { font-size: 13px; }

/* τ 桥梁提示条（②组显示取自①组的 τ） */
.tau-banner {
  margin: 4px 0 14px;
  font-size: 14px;
  font-weight: 600;
  font-family: var(--font-head);
  letter-spacing: .3px;
  color: var(--accent);
  background: #eaf6f8;
  border: 1px solid #bfe3e8;
  padding: 9px 12px;
  border-radius: 4px;
}
.tau-banner.warn { color: #b45309; background: #fef3e2; border-color: #f5d9a8; }

/* 标签内小字说明 */
.form-group label small {
  display: block;
  font-family: var(--font-body);
  text-transform: none;
  letter-spacing: 0;
  color: var(--muted);
  font-size: 12px;
  margin-top: 2px;
}

/* ============ 被锁定（求解目标）的输入态 ============ */
input:disabled, select:disabled {
  background: #f1f4f5;
  color: #9aa7ad;
  cursor: not-allowed;
  border-color: #e0e6e8;
}
.row-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 10px;
}
.solve-pick {
  font-family: var(--font-body);
  text-transform: none;
  letter-spacing: 0;
  font-size: 13px;
  color: var(--muted);
  display: flex;
  align-items: center;
  gap: 5px;
  cursor: pointer;
  white-space: nowrap;
  margin-bottom: 4px;
}
.form-group.solved .row-head label,
.form-group.solved .row-head .flabel-main { color: var(--accent); }

/* ============ 求解状态提示 ============ */
.solve-status {
  margin-top: 12px;
  font-size: 14px;
  color: var(--accent);
  font-family: var(--font-body);
}

/* ============ 分压器左右分栏 ============ */
.split {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 24px;
  align-items: start;
}
.panel {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 22px 24px;
  position: sticky;
  top: 16px;
}
.panel-note {
  font-size: 14px;
  color: var(--muted);
  margin: 0 0 16px;
  line-height: 1.6;
}
.style-accent { color: var(--accent) !important; }

/* ============ 响应式（适合 WP 内容栏/iframe 窄宽） ============ */
@media (max-width: 860px) {
  .split { grid-template-columns: 1fr; }
  .panel { position: static; }
}
@media (max-width: 700px) {
  .form-grid { grid-template-columns: 1fr; }
  .wp-site-title { font-size: 26px; }
  .page-header h1 { font-size: 24px; }
}