/* ====== 温暖书桌 · 共享样式 ====== */
/* accent色由各页面 inline 覆写 :root 中的 --accent / --accent-hover */

:root {
  --paper: #FFF9F0;
  --card: #FFFFFF;
  --ink: #3B3228;
  --ink-light: #8B7E6E;
  --border: #E6DDD0;
  --bg: #FDF5E8;
  --radius: 14px;
  --shadow: 0 2px 12px rgba(60, 40, 20, 0.06);
  --container-width: 960px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', -apple-system, sans-serif;
  background: var(--bg);
  min-height: 100vh;
  padding: 40px 24px;
  display: flex;
  justify-content: center;
  -webkit-font-smoothing: antialiased;
  color: var(--ink);
}

.container { max-width: var(--container-width); width: 100%; }

/* ====== 顶部导航 ====== */
.top-nav { margin-bottom: 8px; display: flex; gap: 6px; justify-content: flex-end; }
.top-nav a, .top-nav span.current {
  padding: 6px 16px; border-radius: 20px;
  font-size: 14px; font-weight: 600; text-decoration: none;
  transition: all 0.15s;
}
.top-nav a { color: var(--ink-light); border: 1px solid transparent; }
.top-nav a:hover { color: var(--accent); border-color: var(--accent); background: var(--paper); }
.top-nav span.current { color: #FFFFFF; background: var(--accent); }

.header-badge {
  font-size: 12px; font-weight: 500; color: var(--ink-light);
  background: var(--bg); padding: 6px 14px; border-radius: 20px;
  border: 1px solid var(--border);
}

/* ====== Header ====== */
.header {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px 32px;
  margin-bottom: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.header h1 { font-size: 24px; font-weight: 700; }
.header p { font-size: 14px; color: var(--ink-light); margin-top: 3px; }

/* ====== 控制栏布局 ====== */
.controls-row {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  gap: 16px 28px;
}
.controls-row + .controls-row {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
.control-group { display: flex; flex-direction: column; gap: 6px; }
.control-group > label {
  font-size: 11px; font-weight: 600; color: var(--ink-light);
  letter-spacing: 0.5px; text-transform: uppercase;
}

/* ====== 分段按钮通用 ====== */
.grade-btns, .count-btns, .page-btns, .semester-btns, .mode-btns, .size-btns {
  display: flex;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border);
}
.grade-btn, .count-btn, .page-btn, .semester-btn, .mode-btn, .size-btn {
  padding: 7px 16px; border: none; border-right: 1px solid var(--border);
  background: var(--card); font-size: 13px; font-weight: 500;
  color: var(--ink); cursor: pointer; transition: all 0.15s;
  font-family: inherit;
}
.grade-btn:last-child, .count-btn:last-child, .page-btn:last-child,
.semester-btn:last-child, .mode-btn:last-child, .size-btn:last-child { border-right: none; }
.grade-btn:hover, .count-btn:hover, .page-btn:hover,
.semester-btn:hover, .mode-btn:hover, .size-btn:hover { background: var(--paper); }
.grade-btn.active, .count-btn.active, .page-btn.active,
.semester-btn.active, .mode-btn.active, .size-btn.active { background: var(--accent); color: #FFFFFF; }

/* ====== 自定义数字输入 ====== */
.count-input {
  width: 56px; padding: 7px 8px;
  border: 1px solid var(--border); border-radius: var(--radius);
  font-size: 13px; text-align: center; font-weight: 500;
  color: var(--ink); font-family: inherit; margin-left: 6px;
}
.count-input:focus { outline: none; border-color: var(--accent); box-shadow: 0 0 0 3px rgba(128,128,128,0.15); }

/* ====== 题型/单元 Pills ====== */
.type-btn, .unit-btn {
  padding: 6px 14px; border: 1px solid var(--border); border-radius: 20px;
  background: var(--card); font-size: 13px; color: var(--ink);
  cursor: pointer; transition: all 0.15s; font-family: inherit;
}
.type-btn:hover, .unit-btn:hover { border-color: var(--accent); color: var(--accent); }
.type-btn.active, .unit-btn.active { background: var(--accent); border-color: var(--accent); color: #FFFFFF; }

/* ====== 按钮系统 ====== */
.actions { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.print-tip { font-size: 11px; color: var(--ink-light); line-height: 1.3; max-width: 200px; }
.btn {
  padding: 10px 26px; border: none; border-radius: 24px;
  font-size: 14px; font-weight: 600; cursor: pointer;
  transition: all 0.2s; font-family: inherit;
}
.btn-gen { background: var(--accent); color: #FFFFFF; }
.btn-gen:hover { background: var(--accent-hover); transform: translateY(-1px); box-shadow: 0 4px 16px rgba(128,128,128,0.35); }
.btn-print { background: var(--ink); color: #FFFFFF; }
.btn-print:hover { background: #4A3F35; transform: translateY(-1px); box-shadow: 0 4px 16px rgba(59, 50, 40, 0.25); }

/* ====== 纸张系统 ====== */
.paper {
  background: var(--card);
  border-radius: var(--radius);
  padding: 32px 28px;
  border: 1px solid var(--border);
  margin-bottom: 20px;
  box-shadow: var(--shadow);
}
.paper-header {
  text-align: center;
  margin-bottom: 20px;
  padding-bottom: 14px;
  border-bottom: 1.5px solid var(--ink);
}
.paper-header h2 { font-size: 20px; color: var(--ink); letter-spacing: 2px; font-weight: 600; }
.paper-header .page-num { float: right; font-size: 12px; color: var(--ink-light); }
.paper-meta {
  display: flex; justify-content: center; gap: 18px;
  margin-top: 8px; font-size: 13px; color: var(--ink-light);
  flex-wrap: wrap;
}
.paper-meta .blank {
  display: inline-block; border-bottom: 1px solid var(--ink-light);
  min-width: 72px; margin-left: 2px;
}
.paper-page { page-break-after: always; }

/* ====== 分数竖式 ====== */
.frac {
  display: inline-flex; flex-direction: column; align-items: center;
  vertical-align: middle; line-height: 1; margin: 0 3px;
}
.frac .num { padding: 1px 5px 0; border-bottom: 1.5px solid var(--ink); color: var(--ink); }
.frac .den { padding: 0 5px 1px; color: var(--ink); }

.print-footer { display: none; }

/* ====== 共享打印规则 ====== */
@media print {
  body { background: #ffffff !important; padding: 0; margin: 0; -webkit-print-color-adjust: exact; print-color-adjust: exact; }
  .header, .controls, .btn { display: none !important; }
  .paper {
    background: #ffffff !important; box-shadow: none !important; border-radius: 0;
    padding: 16px 20px; margin: 0; border: none;
    height: 267mm; width: 210mm;
    box-sizing: border-box;
    display: flex; flex-direction: column;
    page-break-after: always;
    break-after: page;
  }
  .paper:last-child { page-break-after: auto; break-after: auto; }
  .paper-header { margin-bottom: 10px; padding-bottom: 8px; }
  .paper-header h2 { font-size: 18px; color: #000000 !important; font-weight: 800; }
  .paper-header .page-num { display: none; }
  .paper-meta { font-size: 12px; gap: 14px; color: #333333 !important; font-weight: 500 !important; }
  .print-footer { display: block; text-align: center; font-size: 6px; color: #999999 !important; padding-top: 2px; flex-shrink: 0; }
  @page { margin: 8mm; size: A4 portrait; }
}

/* ====== 全局页脚 ====== */
.site-footer {
  text-align: center; margin-top: 32px; padding-bottom: 20px;
  font-size: 12px; color: var(--ink-light);
}
.site-footer a { color: var(--ink-light); text-decoration: none; }
.site-footer a:hover { color: var(--accent); }

@media print { .site-footer { display: none; } }

/* ====== 共享响应式 ====== */
@media (max-width: 700px) {
  body { padding: 12px; }
  .header { padding: 20px; flex-direction: column; text-align: center; gap: 10px; }
  .controls { padding: 16px; }
  .paper { padding: 16px; }
  .paper-meta { flex-wrap: wrap; gap: 10px; }
  .top-nav { justify-content: center; }
  .actions .btn { flex: 1; text-align: center; }
  .print-tip { max-width: none; white-space: normal; }
}