:root {
  --bg: #0a0a0c;
  --bg-2: #121216;
  --panel: rgba(22, 22, 28, 0.72);
  --panel-solid: #16161c;
  --stroke: rgba(255, 255, 255, 0.08);
  --stroke-strong: rgba(255, 255, 255, 0.16);
  --txt: #f3f3f6;
  --txt-dim: #9a9aa8;
  --txt-mute: #6a6a76;
  --accent: #ff5b2e;
  --accent-2: #ffb347;
  --good: #2dd4bf;
  --focus-color: #2dd4bf;
  --radius: 16px;
  --radius-sm: 10px;
  --shadow: 0 18px 48px -28px rgba(0, 0, 0, 0.9);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--txt);
  font-family: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, sans-serif;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

body {
  position: relative;
  overflow-x: hidden;
  background:
    radial-gradient(900px 600px at 80% -10%, rgba(255, 91, 46, 0.12), transparent 60%),
    radial-gradient(700px 500px at -5% 30%, rgba(45, 212, 191, 0.08), transparent 55%),
    var(--bg);
}

.bg-grid {
  position: fixed;
  inset: 0;
  z-index: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse at 50% 0%, #000 30%, transparent 75%);
  pointer-events: none;
}

.app {
  position: relative;
  z-index: 1;
  max-width: 980px;
  margin: 0 auto;
  padding: 48px 24px 80px;
}

/* hero */
.hero { margin-bottom: 36px; }
.eyebrow {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 0.32em;
  color: var(--accent);
  font-weight: 700;
  border: 1px solid rgba(255, 91, 46, 0.35);
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(255, 91, 46, 0.08);
}
.hero h1 {
  font-size: clamp(34px, 6vw, 56px);
  line-height: 1.04;
  margin: 18px 0 12px;
  letter-spacing: -0.02em;
  font-weight: 800;
}
.hero h1 .dot { color: var(--accent); }
.hero h1 .en {
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  font-style: italic;
  letter-spacing: 0.04em;
  margin-left: 4px;
}
.sub { color: var(--txt-dim); font-size: 16px; margin: 0; max-width: 640px; }
.license-note {
  margin-top: 12px; font-size: 12px; color: var(--txt-mute);
  border-left: 2px solid var(--stroke-strong); padding-left: 10px; max-width: 640px;
}

/* panels */
.panel {
  background: var(--panel);
  border: 1px solid var(--stroke);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 20px;
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow);
}
.panel-head {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 12px; margin-bottom: 18px; flex-wrap: wrap;
}
.panel-head h2 { margin: 0; font-size: 18px; font-weight: 700; }
.hint { color: var(--txt-mute); font-size: 13px; }

/* body part grid */
.part-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(110px, 1fr));
  gap: 12px;
}
.part-card {
  position: relative;
  background: var(--panel-solid);
  border: 1px solid var(--stroke);
  border-radius: var(--radius-sm);
  padding: 18px 12px;
  text-align: center;
  cursor: pointer;
  transition: transform 0.16s ease, border-color 0.16s ease, background 0.16s ease;
  user-select: none;
}
.part-card:hover { transform: translateY(-3px); border-color: var(--stroke-strong); }
.part-card .glyph { font-size: 30px; line-height: 1; margin-bottom: 10px; display:block; }
.part-card .label { font-size: 15px; font-weight: 600; }
.part-card .en { display:block; font-size: 11px; color: var(--txt-mute); margin-top: 3px; letter-spacing: 0.04em; }
.part-card.selected {
  border-color: var(--accent);
  background: linear-gradient(180deg, rgba(255,91,46,0.18), rgba(255,91,46,0.05));
  box-shadow: 0 0 0 1px var(--accent), 0 12px 28px -16px rgba(255,91,46,0.5);
}
.part-card.selected::after {
  content: "✓";
  position: absolute; top: 8px; right: 10px;
  color: var(--accent); font-weight: 800; font-size: 14px;
}

/* cta row */
.cta-row {
  display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
  margin-bottom: 24px;
}
.primary-btn {
  position: relative;
  border: none;
  cursor: pointer;
  padding: 14px 28px;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 700;
  color: #1a0e08;
  background: linear-gradient(135deg, var(--accent-2), var(--accent));
  box-shadow: 0 14px 32px -14px rgba(255, 91, 46, 0.7);
  transition: transform 0.14s ease, box-shadow 0.14s ease;
  overflow: hidden;
}
.primary-btn:hover:not(:disabled) { transform: translateY(-2px); box-shadow: 0 18px 38px -14px rgba(255, 91, 46, 0.8); }
.primary-btn:active:not(:disabled) { transform: translateY(0); }
.primary-btn:disabled { opacity: 0.4; cursor: not-allowed; filter: grayscale(0.4); }
.btn-shine {
  position: absolute; top: 0; left: -120%;
  width: 80%; height: 100%;
  background: linear-gradient(100deg, transparent, rgba(255,255,255,0.45), transparent);
  transform: skewX(-18deg);
  transition: left 0.6s ease;
}
.primary-btn:hover .btn-shine { left: 140%; }
.ghost-btn {
  background: transparent; border: 1px solid var(--stroke-strong);
  color: var(--txt-dim); cursor: pointer;
  padding: 14px 20px; border-radius: 12px; font-size: 15px; font-weight: 600;
  transition: all 0.14s ease;
}
.ghost-btn:hover { color: var(--txt); border-color: var(--accent); }
.selection-readout {
  margin-left: auto; color: var(--txt-mute); font-size: 14px;
  border: 1px dashed var(--stroke-strong); padding: 8px 14px; border-radius: 10px;
}
.selection-readout b { color: var(--accent); }

/* result */
.result, .library { animation: fadeUp 0.4s ease; }
@keyframes fadeUp { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: none; } }

.plan-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 12px; }
.plan-item {
  display: grid;
  grid-template-columns: 44px 1fr auto;
  gap: 16px;
  align-items: start;
  background: var(--panel-solid);
  border: 1px solid var(--stroke);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  transition: border-color 0.14s ease;
}
.plan-item:hover { border-color: var(--stroke-strong); }
.plan-num {
  width: 44px; height: 44px; border-radius: 12px;
  display: grid; place-items: center;
  font-weight: 800; font-size: 18px;
  background: linear-gradient(135deg, rgba(255,91,46,0.25), rgba(255,179,71,0.12));
  color: var(--accent-2);
  border: 1px solid rgba(255, 91, 46, 0.3);
}
.plan-body { min-width: 0; }
.plan-name { font-size: 17px; font-weight: 700; margin-bottom: 4px; }
.plan-cn { color: var(--txt-dim); font-size: 13px; margin-bottom: 8px; }
.plan-chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chip {
  font-size: 12px; padding: 3px 9px; border-radius: 999px;
  background: rgba(255,255,255,0.05); border: 1px solid var(--stroke);
  color: var(--txt-dim);
}
.chip.eq { color: var(--good); border-color: rgba(45,212,191,0.3); background: rgba(45,212,191,0.08); }
.chip.target { color: var(--accent-2); border-color: rgba(255,179,71,0.3); background: rgba(255,179,71,0.08); }
.plan-prescribe {
  text-align: right; min-width: 130px;
}
.plan-prescribe .big {
  font-size: 22px; font-weight: 800; color: var(--txt);
  letter-spacing: -0.01em;
}
.plan-prescribe .rest { display:block; color: var(--txt-mute); font-size: 12px; margin-top: 3px; }
.plan-steps {
  grid-column: 2 / -1;
  margin: 4px 0 0; padding: 0 0 0 18px;
  color: var(--txt-dim); font-size: 13.5px; line-height: 1.7;
  border-left: 2px solid var(--accent);
}
.plan-steps li { margin-bottom: 2px; }
.plan-toggle {
  grid-column: 2 / -1;
  background: none; border: none; color: var(--accent);
  cursor: pointer; font-size: 13px; font-weight: 600; padding: 4px 0; text-align: left;
}
.plan-toggle:hover { color: var(--accent-2); }

/* library grid */
.lib-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 10px;
}
.lib-card {
  background: var(--panel-solid);
  border: 1px solid var(--stroke);
  border-radius: var(--radius-sm);
  padding: 14px;
  display: flex; flex-direction: column; gap: 6px;
  transition: border-color 0.14s ease, transform 0.14s ease;
}
.lib-card:hover { border-color: var(--stroke-strong); transform: translateY(-2px); }
.lib-name { font-weight: 700; font-size: 15px; }
.lib-cn { font-size: 13px; color: var(--txt-dim); }
.lib-chips { display: flex; flex-wrap: wrap; gap: 6px; }
.lib-steps { font-size: 13px; color: var(--txt-dim); line-height: 1.65; margin: 4px 0 0; }

/* footer */
.foot { text-align: center; color: var(--txt-mute); font-size: 12px; letter-spacing: 0.18em; margin-top: 36px; font-weight: 600; }

/* loader + toast */
.loader {
  position: fixed; inset: 0; z-index: 50;
  background: rgba(10,10,12,0.85); backdrop-filter: blur(8px);
  display: grid; place-items: center; gap: 14px; color: var(--txt-dim);
}
.spinner {
  width: 42px; height: 42px; border-radius: 50%;
  border: 3px solid var(--stroke-strong); border-top-color: var(--accent);
  animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }
.toast {
  position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%);
  background: var(--panel-solid); border: 1px solid var(--stroke-strong);
  color: var(--txt); padding: 12px 20px; border-radius: 12px;
  font-size: 14px; z-index: 60; box-shadow: var(--shadow);
}
.toast.err { border-color: var(--accent); }

.hidden { display: none !important; }

@media (max-width: 620px) {
  .plan-item { grid-template-columns: 36px 1fr; }
  .plan-prescribe { grid-column: 2; text-align: left; }
  .plan-steps, .plan-toggle { grid-column: 1 / -1; }
  .selection-readout { margin-left: 0; width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}