/* ================================
   CSS 单位换算工具 - 自定义样式
   配色与 Leowh 主页统一
   ================================ */

:root {
  --bg: #FAFAF9;
  --bg-alt: #F5F5F4;
  --surface: #FFFFFF;
  --border: #E7E5E4;
  --border-strong: #D6D3D1;
  --text: #1E293B;
  --text-secondary: #52525B;
  --text-muted: #71717A;
  --primary: #4F46E5;
  --primary-hover: #4338CA;
  --primary-light: rgba(79, 70, 229, 0.08);
  --secondary: #F97316;
  --accent: #EC4899;
  --success: #059669;
  --radius: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow: 0 4px 12px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.08);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', 'Noto Sans SC', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
}

.toast {
  position: fixed; top: 24px; right: 24px;
  background: var(--text); color: var(--bg);
  padding: 10px 18px; border-radius: 100px;
  font-size: 14px; font-weight: 500;
  display: flex; align-items: center; gap: 8px;
  z-index: 1000;
  transform: translateX(calc(100% + 40px));
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
  box-shadow: 0 4px 16px rgba(0,0,0,0.12);
}
.toast.show { transform: translateX(0); }
.toast-dot { width: 8px; height: 8px; background: var(--success); border-radius: 50%; }

.page { max-width: 960px; margin: 0 auto; padding: 0 32px; }

#header.scrolled {
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  box-shadow: 0 2px 20px rgba(0,0,0,0.06);
}

.tool-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

.tool-panel h2 {
  font-size: 16px; font-weight: 700;
  color: var(--text);
  margin-bottom: 20px;
}

.input-row {
  display: flex; gap: 10px; align-items: center;
  margin-bottom: 20px;
}

.input-field {
  flex: 1; min-width: 120px;
  padding: 12px 14px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-family: inherit; font-size: 15px; color: var(--text);
  transition: all 0.2s ease;
  outline: none;
}
.input-field:focus {
  border-color: var(--primary);
  background: var(--surface);
  box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

select.input-field {
  min-width: auto;
  flex: 0 0 auto;
}

.setting-row {
  display: flex; gap: 16px; align-items: center;
  margin-bottom: 20px; flex-wrap: wrap;
}

.setting-label {
  font-size: 13px; color: var(--text-secondary);
  white-space: nowrap;
}

.setting-pills {
  display: flex; gap: 4px;
}

.setting-pill {
  padding: 5px 12px;
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 100px;
  font-family: inherit; font-size: 12px; font-weight: 500;
  color: var(--text-muted); cursor: pointer;
  transition: all 0.15s ease;
}
.setting-pill:hover { border-color: rgba(79,70,229,0.25); color: var(--primary); }
.setting-pill.active { background: var(--primary); border-color: var(--primary); color: white; }

.result-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 10px;
}

.result-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  transition: all 0.2s ease;
}
.result-card:hover {
  border-color: var(--primary);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(79, 70, 229, 0.08);
}

.result-card-unit {
  font-size: 11px; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.result-card-value {
  font-family: 'SF Mono', 'Cascadia Code', monospace;
  font-size: 16px; font-weight: 600;
  color: var(--text);
  word-break: break-all;
}

.result-card-copy {
  float: right;
  font-size: 11px;
  color: var(--primary);
  background: none;
  border: none;
  cursor: pointer;
  font-weight: 500;
  opacity: 0;
  transition: opacity 0.15s ease;
}
.result-card:hover .result-card-copy { opacity: 1; }

.guide-section {
  margin-top: 16px;
  margin-bottom: 64px;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}
.guide-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  padding: 14px 20px;
  background: none;
  border: none;
  cursor: pointer;
  transition: background 0.15s ease;
}
.guide-toggle:hover { background: var(--bg-alt); }
.guide-toggle-title {
  display: flex; align-items: center; gap: 8px;
  font-size: 14px; font-weight: 600; color: #1E293B;
}
.guide-toggle.open .toggle-arrow { transform: rotate(180deg); }
.toggle-arrow {
  transition: transform 0.2s ease;
  color: var(--text-muted);
}
.guide-list { padding: 0 20px 20px; }
.guide-list.hidden { display: none; }
.guide-item {
  padding: 16px 0; border-top: 1px solid var(--border);
}
.guide-item:first-child { border-top: 1px solid var(--border); }
.guide-item-title {
  font-size: 14px; font-weight: 600;
  color: #1E293B; margin-bottom: 6px;
}
.guide-item-body {
  font-size: 13px; color: var(--text-secondary);
  line-height: 1.8;
}
.guide-item-body kbd {
  padding: 1px 6px;
  background: var(--bg-alt);
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  font-family: 'SF Mono', 'Cascadia Code', monospace;
  font-size: 12px;
  color: var(--text-secondary);
}

::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: #f1f5f9; }
::-webkit-scrollbar-thumb { background: #A5B4FC; border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: #4F46E5; }

::selection { background: rgba(79, 70, 229, 0.2); color: #1E293B; }

@media (max-width: 768px) {
  .page { padding: 0 16px; }
  .input-row { flex-wrap: wrap; }
  .input-field { min-width: 100%; }
  .result-grid { grid-template-columns: 1fr; }
}