* {
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, #4e54c8, #8f94fb);
  min-height: 100vh;
  margin: 0;
  padding: 2rem 1rem;
  display: flex;
  justify-content: center;
  align-items: flex-start;
  color: #fff;
}

h1 {
  text-align: center;
  font-weight: 700;
  font-size: 3rem;
  margin-bottom: 2rem;
  text-shadow: 2px 2px 8px rgba(0,0,0,0.3);
  user-select: none;
  letter-spacing: 1.2px;
  color: #f0f8ff;
}

form#sizeForm {
  background: rgba(255, 255, 255, 0.18);
  padding: 2.5rem 3rem;
  border-radius: 20px;
  max-width: 480px;
  width: 100%;
  box-shadow: 0 16px 36px rgba(0,0,0,0.3);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  user-select: none;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}

form label {
  font-weight: 700;
  font-size: 1.15rem;
  color: #e0e7ff;
  text-shadow: 0 0 4px rgba(0,0,0,0.4);
}

form input[type="number"],
form select {
  padding: 0.75rem 1.2rem;
  border-radius: 16px;
  border: none;
  font-size: 1.15rem;
  font-weight: 600;
  background: rgba(255, 255, 255, 0.35);
  color: #111;
  box-shadow:
    inset 3px 3px 7px rgba(255,255,255,0.75),
    inset -3px -3px 7px rgba(0,0,0,0.15);
  transition: background-color 0.3s ease, color 0.3s ease, box-shadow 0.3s ease;
}

form input[type="number"]::placeholder {
  color: #666;
}

form input[type="number"]:focus,
form select:focus {
  outline: none;
  background: #fff;
  color: #222;
  box-shadow:
    0 0 10px 4px #7c92ff,
    inset 1px 1px 3px rgba(255,255,255,0.9);
}

form button {
  margin-top: 1rem;
  padding: 0.85rem 0;
  background: #ff4d6d;
  border: none;
  border-radius: 18px;
  font-weight: 800;
  font-size: 1.35rem;
  color: #fff;
  cursor: pointer;
  box-shadow: 0 8px 22px rgba(255, 77, 109, 0.75);
  transition: background-color 0.3s ease, transform 0.2s ease, box-shadow 0.3s ease;
  user-select: none;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

form button:hover {
  background: #ff1e49;
  box-shadow: 0 12px 32px rgba(255, 30, 73, 0.9);
  transform: scale(1.07);
}

form button:active {
  transform: scale(0.96);
}

.results {
  margin-top: 2.5rem;
  background: rgba(255, 255, 255, 0.22);
  border-radius: 20px;
  padding: 2rem 2.5rem;
  max-width: 480px;
  width: 100%;
  box-shadow: 0 14px 38px rgba(0,0,0,0.38);
  user-select: none;
  color: #fff;
  text-align: center;
  font-weight: 600;
  letter-spacing: 0.03em;
}

.results h2 {
  margin: 0 0 1.3rem 0;
  font-weight: 900;
  font-size: 2rem;
  color: #fafafa;
  text-shadow: 2px 2px 10px rgba(0,0,0,0.5);
}

.results table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0 12px;
  font-weight: 700;
  font-size: 1.15rem;
  background: transparent;
  border-radius: 14px;
  overflow: hidden;
}

.results th,
.results td {
  padding: 1rem 1.3rem;
  background: rgba(255, 255, 255, 0.15);
  color: #f5f5f5;
  text-shadow: 0 0 3px rgba(0,0,0,0.35);
  transition: background-color 0.3s ease;
}

.results th {
  background: #6c63ff;
  color: #fff;
  font-size: 1.25rem;
  text-align: center;
  letter-spacing: 0.07em;
  user-select: none;
}

.results td {
  text-align: center;
  border-radius: 10px;
}

.results tr:nth-child(even) td {
  background: rgba(255, 255, 255, 0.10);
}

@media (max-width: 480px) {
  h1 {
    font-size: 2.2rem;
  }
  form#sizeForm, .results {
    padding: 1.8rem 2rem;
  }
  form button {
    font-size: 1.2rem;
  }
  .results h2 {
    font-size: 1.6rem;
  }
  .results table {
    font-size: 1rem;
  }
}