/* ================================
   CSS 渐变生成器 - 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: #EC4899;
  --primary-hover: #DB2777;
  --primary-light: rgba(236,72,153,0.08);
  --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.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);
}

/* ══════════════════════════════════════════
   Gradient Section
   ══════════════════════════════════════════ */
.gradient-section { position: relative; z-index: 10; }

.gradient-panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow);
}

.gradient-controls {
  display: flex; align-items: flex-end; gap: 20px; flex-wrap: wrap;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--bg-alt);
}

.control-group {
  display: flex; flex-direction: column; gap: 6px;
}
.control-label {
  font-size: 12px; font-weight: 600; color: var(--text-muted);
  text-transform: uppercase; letter-spacing: 0.05em;
}
.control-select {
  padding: 10px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-family: inherit; font-size: 14px; color: var(--text);
  outline: none; cursor: pointer; min-width: 160px;
  transition: border-color 0.2s ease;
}
.control-select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(236,72,153,0.1);
}
.control-range {
  width: 160px; accent-color: var(--primary);
}
.range-value {
  font-size: 13px; font-weight: 600; color: var(--text-secondary);
}

/* ── Preview Canvas ── */
.gradient-preview-wrapper {
  padding: 0;
  border-bottom: 1px solid var(--border);
}
.gradient-canvas {
  display: block; width: 100%; height: 240px;
  background: repeating-conic-gradient(#f0f0f0 0% 25%, #fff 0% 50%) 50% / 20px 20px;
}

/* ── Color Stops ── */
.gradient-stops {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
}
.gradient-stops-header {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 14px;
}
.btn-add-stop {
  padding: 7px 16px;
  background: var(--primary);
  border: 1px solid transparent;
  border-radius: 100px;
  font-family: inherit; font-size: 12px; font-weight: 600;
  color: white; cursor: pointer;
  transition: background 0.15s ease;
}
.btn-add-stop:hover { background: var(--primary-hover); }

.gradient-stops-list {
  display: flex; flex-direction: column; gap: 8px; margin-bottom: 16px;
}
.stop-row {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
  padding: 10px 14px;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.stop-color {
  width: 36px; height: 36px; border: 2px solid var(--border);
  border-radius: 8px; cursor: pointer; padding: 0;
  background: none; flex-shrink: 0;
}
.stop-position {
  width: 80px; padding: 7px 10px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-family: inherit; font-size: 14px; color: var(--text);
  outline: none;
  transition: border-color 0.2s ease;
}
.stop-position:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(236,72,153,0.1);
}
.stop-pct {
  font-size: 13px; color: var(--text-muted);
}
.stop-remove {
  padding: 6px 12px;
  background: transparent; border: 1px solid var(--border);
  border-radius: 100px;
  font-family: inherit; font-size: 12px; font-weight: 500;
  color: #EF4444; cursor: pointer; margin-left: auto;
  transition: background 0.15s ease;
}
.stop-remove:hover { background: rgba(239,68,68,0.08); }

/* ── Gradient Bar (draggable visual) ── */
.gradient-bar-wrapper { margin-top: 8px; }
.gradient-bar {
  position: relative; height: 32px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  cursor: pointer;
  overflow: visible;
}
.gradient-bar-track {
  position: absolute; inset: 0; border-radius: inherit;
}
.gradient-bar-handles {
  position: absolute; inset: 0;
}
.gradient-handle {
  position: absolute; top: -6px;
  width: 16px; height: 44px;
  background: white;
  border: 2px solid #333;
  border-radius: 6px;
  cursor: grab;
  transform: translateX(-50%);
  box-shadow: 0 2px 6px rgba(0,0,0,0.2);
  z-index: 2;
  transition: box-shadow 0.15s ease;
}
.gradient-handle:active { cursor: grabbing; box-shadow: 0 4px 12px rgba(0,0,0,0.3); }
.gradient-handle.active { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(236,72,153,0.3); }

/* ── CSS Code Output ── */
.gradient-code { padding: 20px 24px; }
.gradient-code-header {
  display: flex; align-items: center; justify-content: space-between;
  margin-bottom: 10px;
}
.gradient-code-title {
  font-size: 15px; font-weight: 700; color: var(--text);
}
.btn-sm {
  padding: 7px 16px;
  background: transparent; border: 1px solid var(--border);
  border-radius: 100px;
  font-family: inherit; font-size: 12px; font-weight: 500;
  color: var(--text-secondary); cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.btn-sm:hover {
  background: var(--primary-light);
  border-color: rgba(236,72,153,0.25);
  color: var(--primary);
}
.gradient-code-block {
  padding: 16px 18px;
  background: #1e1e1e;
  border-radius: var(--radius);
  font-family: 'SF Mono', 'Cascadia Code', 'Fira Code', monospace;
  font-size: 14px; color: #d4d4d4;
  overflow-x: auto; margin: 0; white-space: pre-wrap;
}

/* ══════════════════════════════════════════
   Scrollbar & Selection
   ══════════════════════════════════════════ */
::-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; }

/* ══════════════════════════════════════════
   Guide Section
   ══════════════════════════════════════════ */
.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);
}

/* ══════════════════════════════════════════
   Responsive
   ══════════════════════════════════════════ */
@media (max-width: 768px) {
  .page { padding: 0 16px; }
  .gradient-controls { flex-direction: column; align-items: stretch; }
  .control-range { width: 100%; }
  .gradient-canvas { height: 180px; }
  .stop-row { flex-direction: column; align-items: stretch; }
  .stop-remove { margin-left: 0; align-self: flex-end; }
}