/* ================================
   随机字符串生成器 - 自定义样式
   ================================ */

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

/* ── Header scroll effect ── */
#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);
}

/* ══════════════════════════════════════════
   Generator Section
   ══════════════════════════════════════════ */
.generator-section { padding: 8px 0 32px; }

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}
.panel:hover { box-shadow: 0 8px 30px rgba(0,0,0,0.08); }

.panel-body { padding: 24px; }

/* ── Control Grid ── */
.control-grid {
  display: flex;
  flex-direction: column;
  gap: 20px;
  margin-bottom: 24px;
}

.control-block { }

.config-label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 10px;
}

/* ── Charset Options ── */
.charset-options {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 8px;
}

.charset-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.15s ease;
  background: var(--bg-alt);
}
.charset-option:hover { border-color: rgba(6,182,212,0.4); background: var(--surface); }
.charset-option.selected {
  border-color: #06B6D4;
  background: rgba(6,182,212,0.06);
  box-shadow: 0 0 0 1px rgba(6,182,212,0.2);
}

.charset-option input[type="radio"] { display: none; }

.charset-radio {
  width: 18px;
  height: 18px;
  border: 2px solid var(--border-strong);
  border-radius: 50%;
  flex-shrink: 0;
  position: relative;
  transition: all 0.15s ease;
}
.charset-option.selected .charset-radio {
  border-color: #06B6D4;
}
.charset-option.selected .charset-radio::after {
  content: '';
  position: absolute;
  top: 3px; left: 3px;
  width: 8px; height: 8px;
  background: #06B6D4;
  border-radius: 50%;
}

.charset-name {
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  min-width: 80px;
}

.charset-sample {
  font-size: 11px;
  color: var(--text-muted);
  font-family: 'SF Mono', 'Cascadia Code', monospace;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ── Custom Charset Input ── */
.custom-charset-wrap {
  margin-top: 10px;
}

.custom-charset-input {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
  font-size: 14px;
  color: var(--text);
  transition: all 0.2s ease;
  outline: none;
}
.custom-charset-input:focus {
  border-color: #06B6D4;
  background: var(--surface);
  box-shadow: 0 0 0 3px rgba(6,182,212,0.1);
}
.custom-charset-input::placeholder { color: #9CA3AF; font-family: inherit; }

/* ── Length Control ── */
.length-control {
  display: flex;
  align-items: center;
  gap: 14px;
}

.length-slider {
  flex: 1;
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  background: var(--border);
  border-radius: 100px;
  outline: none;
}
.length-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #06B6D4;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(6,182,212,0.3);
  transition: transform 0.15s ease;
}
.length-slider::-webkit-slider-thumb:hover { transform: scale(1.1); }
.length-slider::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #06B6D4;
  cursor: pointer;
  border: none;
  box-shadow: 0 2px 6px rgba(6,182,212,0.3);
}

.length-value {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  padding: 4px 12px;
  background: #06B6D4;
  color: white;
  font-size: 14px;
  font-weight: 700;
  border-radius: 100px;
}

/* ── Quantity Selector ── */
.quantity-selector {
  display: flex;
  gap: 4px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: 100px;
  padding: 3px;
  width: fit-content;
}

.qty-option {
  padding: 6px 14px;
  background: transparent;
  border: none;
  border-radius: 100px;
  font-family: inherit;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.15s ease;
}
.qty-option:hover { color: var(--text); }
.qty-option.active {
  background: var(--surface);
  color: var(--text);
  box-shadow: 0 1px 3px rgba(0,0,0,0.08);
}

/* ── Generate Bar ── */
.generate-bar {
  display: flex;
  gap: 10px;
  margin-bottom: 24px;
}

.btn-generate {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: linear-gradient(135deg, #06B6D4, #3B82F6);
  border: none;
  border-radius: 100px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 600;
  color: white;
  cursor: pointer;
  transition: all 0.15s ease;
  box-shadow: 0 2px 8px rgba(6,182,212,0.3);
}
.btn-generate:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(6,182,212,0.4);
}
.btn-generate:active { transform: translateY(0); }

.btn-copy-all {
  padding: 12px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 100px;
  font-family: inherit;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.15s ease;
}
.btn-copy-all:hover {
  background: var(--primary-light);
  border-color: rgba(79,70,229,0.25);
  color: var(--primary);
}

/* ── Result List ── */
.result-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.result-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 48px 20px;
}

.result-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-bottom: none;
  background: var(--bg-alt);
  transition: all 0.2s ease;
}
.result-item:first-child { border-radius: var(--radius) var(--radius) 0 0; }
.result-item:last-child { border-bottom: 1px solid var(--border); border-radius: 0 0 var(--radius) var(--radius); }
.result-item:hover { background: var(--surface); }

.result-index {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  min-width: 24px;
  text-align: right;
}

.result-value {
  flex: 1;
  font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
  font-size: 15px;
  color: var(--text);
  word-break: break-all;
}

.result-copy-btn {
  padding: 5px 14px;
  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;
  white-space: nowrap;
}
.result-copy-btn:hover {
  background: var(--primary-light);
  border-color: rgba(79,70,229,0.25);
  color: var(--primary);
}

/* ══════════════════════════════════════════
   Custom scrollbar
   ══════════════════════════════════════════ */
::-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(6, 182, 212, 0.2); color: #1E293B; }

/* ══════════════════════════════════════════
   Guide Section (accordion)
   ══════════════════════════════════════════ */
.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 code {
  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;
}

/* ══════════════════════════════════════════
   Responsive
   ══════════════════════════════════════════ */
@media (max-width: 768px) {
  .page { padding: 0 16px; }

  .charset-options { grid-template-columns: 1fr; }
  .generate-bar { flex-direction: column; }
  .btn-generate, .btn-copy-all { justify-content: center; }
}