body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  background: #f5f5f5;
  margin: 0;
  padding: 0;
}

.container {
  max-width: 520px;
  margin: auto;
  padding: 20px;
  background: #fff;
  min-height: 100vh;
}

h1 {
  margin-bottom: 18px;
}

label {
  display: block;
  margin-top: 10px;
}

.weight-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 4px;
}

.weight-row input {
  width: 120px;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #ccc;
  font-size: 16px;
}

.strength-grid {
  margin-top: 8px;
  display: grid;
  row-gap: 10px;
}

.main-btn {
  margin-top: 16px;
  width: 100%;
  padding: 12px;
  font-size: 16px;
  border: none;
  border-radius: 10px;
  background: #2563eb;
  color: #fff;
}

.result {
  margin-top: 16px;
  padding: 12px;
  border-radius: 8px;
  background: #e0f2fe;
}

.scope {
  margin-top: 16px;
  padding: 12px;
  border-radius: 8px;
  background: #fff3cd;
  font-size: 13px;
}

.ref {
  font-size: 13px;
  margin-top: 14px;
}

.warn {
  font-size: 12px;
  color: #666;
}

/* Floating dark mode button */
#darkToggle {
  position: fixed;
  bottom: 18px;
  right: 18px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: #222;
  color: #fff;
  border: none;
  font-size: 20px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.4);
  cursor: pointer;
  z-index: 9999;
}

/* DARK MODE */
.dark {
  background: #111;
  color: #eee;
}

.dark .container {
  background: #1c1c1c;
}

.dark input,
.dark button {
  background: #222;
  color: #fff;
  border: 1px solid #444;
}

.dark .result {
  background: #0f2a3a;
}

.dark .scope {
  background: #3a2f0f;
}

.dark #darkToggle {
  background: #eee;
  color: #000;
}
body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  background: #f5f5f5;
  margin: 0;
  padding: 0;
}

.container {
  max-width: 520px;
  margin: auto;
  padding: 20px;
  background: #fff;
  min-height: 100vh;
}

h1 {
  margin-bottom: 18px;
}

label {
  display: block;
  margin-top: 10px;
}

.weight-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 4px;
}

.weight-row input {
  width: 120px;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #ccc;
  font-size: 16px;
}

.strength-grid {
  margin-top: 8px;
  display: grid;
  row-gap: 10px;
}

.main-btn {
  margin-top: 16px;
  width: 100%;
  padding: 12px;
  font-size: 16px;
  border: none;
  border-radius: 10px;
  background: #2563eb;
  color: #fff;
}

.result {
  margin-top: 16px;
  padding: 12px;
  border-radius: 8px;
  background: #e0f2fe;
}

.scope {
  margin-top: 16px;
  padding: 12px;
  border-radius: 8px;
  background: #fff3cd;
  font-size: 13px;
}

.ref {
  font-size: 13px;
  margin-top: 14px;
}

.warn {
  font-size: 12px;
  color: #666;
}

/* Floating dark mode button */
#darkToggle {
  position: fixed;
  bottom: 18px;
  right: 18px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background: #222;
  color: #fff;
  border: none;
  font-size: 20px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.4);
  cursor: pointer;
  z-index: 9999;
}

/* DARK MODE */
.dark {
  background: #111;
  color: #eee;
}

.dark .container {
  background: #1c1c1c;
}

.dark input,
.dark button {
  background: #222;
  color: #fff;
  border: 1px solid #444;
}

.dark .result {
  background: #0f2a3a;
}

.dark .scope {
  background: #3a2f0f;
}

.dark #darkToggle {
  background: #eee;
  color: #000;
}

.result {
  border: 1px solid #dbeafe;
}