:root {
  --accent: #1dca5c;
  --bg-color: #0f131a;
  --card-bg: #000;
  --text-color: #eaeaea;
  --subtitle-color: #9ca3af;
  --input-bg: #1f1f1f;
  --input-border: #333;
  --warning-color: #ff4c4c;
  --inactive-btn: #555;
}

* {
  box-sizing: border-box;
}

body {
  font-family: "Inter", sans-serif;
  background: var(--bg-color);
  color: var(--text-color);
  margin: 0;
  padding: 20px;
}

.container {
  max-width: 420px;
  margin: 0 auto;
  text-align: center;
}

h1::after {
  content: "";
  display: block;
  width: 60px;
  height: 3px;
  background: var(--accent);
  margin: 8px auto 0;
  border-radius: 2px;
  box-shadow: 0 0 8px rgba(29, 202, 92, 0.6);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.6; transform: scaleX(1); }
  50% { opacity: 1; transform: scaleX(1.2); }
}

.subtitle {
  color: var(--subtitle-color);
  margin-bottom: 1.5rem;
}

.card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: 0 0 12px rgba(0, 0, 0, 0.3);
  text-align: left;
}

label {
  display: block;
  margin-top: 1rem;
  margin-bottom: 0.4rem;
  font-size: 0.9rem;
  color: var(--subtitle-color);
}

input[type="number"],
input[type="range"] {
  width: 100%;
  background: var(--input-bg);
  border: 1px solid var(--input-border);
  color: var(--text-color);
  border-radius: 8px;
  padding: 10px;
  font-size: 1rem;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  height: 6px;
  border-radius: 5px;
  background: var(--input-border);
  outline: none;
  margin-bottom: 4px;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
}

.result {
  margin-top: 2rem;
  text-align: center;
}

.result h2 {
  color: var(--accent);
  font-size: 1.3rem;
  margin-bottom: 0.3rem;
}

#note, #howItWorks-description, #howItWorks {
  color: var(--subtitle-color);
  text-align: center;
}

#howItWorks-details {
  color: var(--subtitle-color);
  font-size: 0.75rem;
  margin-top: 0.5rem;
  line-height: 1.4;
}


.credit {
  text-align: center;
  color: var(--subtitle-color);
}

.credit a {
  color: var(--accent);
  text-decoration: none;
}

.credit a:hover {
  text-decoration: underline;
}

.warning {
  color: var(--warning-color);
  font-size: 0.85rem;
  margin-top: 0.5rem;
}

.buttons {
  text-align: right;
  margin-top: 1rem;
}

button {
  padding: 0.5rem 1rem;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s ease;
  background-color: var(--inactive-btn);
  color: #fff;
  border: none;
}

.theme-buttons {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 1rem;
}

.theme-buttons button.active {
  background-color: var(--accent);
  color: #fff;
  border: none;
}

body.light {
  --bg-color: #f5f5f5;
  --card-bg: #ffffff;
  --text-color: #1f1f1f;
  --accent: #1dca5c;
  --subtitle-color: #6b7280;
  --input-bg: #e5e7eb;
  --input-border: #d1d5db;
  --warning-color: #e11d48;
}

body.pink {
  --bg-color: #ffe6f0;
  --card-bg: #ffb6d5;
  --text-color: #3d003d;
  --accent: #ff4ca1;
  --subtitle-color: #550033;
  --input-bg: #ffd6eb;
  --input-border: #ff9ac1;
  --warning-color: #ff1a75;
}

body, 
.card, 
input, 
button {
  transition: background-color 0.5s ease, 
              color 0.5s ease, 
              border-color 0.5s ease,
              box-shadow 0.5s ease;
}