/* Base styles and reset */
:root {
  --bg: #070b10;
  --panel: rgba(13, 20, 29, 0.78);
  --panel-strong: rgba(17, 27, 38, 0.92);
  --text: #f7fbff;
  --muted: #9cabbb;
  --line: rgba(255, 255, 255, 0.12);
  --amber: #ffbf47;
  --amber-strong: #ff9f1c;
  --green: #34d399;
  --blue: #5cc8ff;
  --red: #ff5a66;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.42);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  min-height: 100%;
  background: var(--bg);
}

html,
body {
  min-height: 100%;
  font-family: 'Manrope', sans-serif;
  color: var(--text);
  line-height: 1.6;
}

body {
  background:
    radial-gradient(circle at 18% 12%, rgba(255, 191, 71, 0.2), transparent 28rem),
    radial-gradient(circle at 85% 20%, rgba(92, 200, 255, 0.16), transparent 24rem),
    linear-gradient(145deg, #111823 0%, #070b10 48%, #020406 100%);
  overflow-x: hidden;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 54px 54px;
  mask-image: linear-gradient(to bottom, #000, transparent 82%);
}

/* Utility classes */
.container {
  margin: 0 auto;
  padding: 0 2rem;
}

.text-center {
  text-align: center;
}

.hidden {
  display: none;
}

.fade-in {
  animation: fadeIn 0.45s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Typography */
h1,
h2 {
  font-family: 'Sora', sans-serif;
  letter-spacing: -0.04em;
}

h1 {
  font-size: clamp(1.1rem, 3vw, 1.7rem);
  font-weight: 700;
}

h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

p {
  margin-bottom: 1rem;
}

/* Form elements */
input,
select,
button {
  font: inherit;
}

input[type="number"] {
  width: 100%;
  padding: 0.95rem 1rem;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.07);
  color: var(--text);
  transition: border-color 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.unit-selector {
  width: 100%;
  padding: 0.95rem 1rem;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.07);
  color: var(--text);
  cursor: pointer;
}

.unit-selector option {
  color: #111823;
}

input[type="number"]::placeholder {
  color: rgba(247, 251, 255, 0.4);
}

input[type="number"]:focus,
select:focus-visible,
button:focus-visible,
input[type="range"]:focus-visible {
  outline: none;
  border-color: var(--amber);
  box-shadow: 0 0 0 4px rgba(255, 191, 71, 0.18);
}

button {
  min-height: 3.25rem;
  padding: 0.85rem 1.2rem;
  border: 0;
  border-radius: 999px;
  color: #071016;
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease, filter 0.2s ease;
  font-weight: 800;
}

button:hover {
  transform: translateY(-2px);
  filter: brightness(1.04);
}

button:active {
  transform: translateY(0);
}