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

body {
  font-family: 'Inter', sans-serif;
  background: linear-gradient(to right, #0f0c29, #302b63, #24243e);
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: 20px;
  color: #f1f1f1;
  position: relative;
}

.converter-container {
  background: black;
  padding: 35px;
  border-radius: 20px;
  box-shadow: 0 0 20px rgba(0,255,255,0.2);
  max-width: 420px;
  width: 100%;
  text-align: center;
  backdrop-filter: blur(8px);
  border: 1px solid rgba(0,255,255,0.1);
  transition: transform 0.3s ease;
}

.converter-container:hover {
  transform: scale(1.015);
}

h1 {
  font-size: 2rem;
  margin-bottom: 10px;
  color: white;
}

.subtext {
  font-size: 0.9rem;
  color: #ccc;
  margin-bottom: 25px;
}

.input-value {
  width: 100%;
  padding: 12px 15px;
  font-size: 1rem;
  border: 2px solid #00eaff;
  border-radius: 10px;
  margin-bottom: 20px;
  background-color: #1c1c2b;
  color: #fff;
  transition: border-color 0.3s;
}

.input-value:focus {
  outline: none;
  border-color: #39f;
}

.select-row {
  display: flex;
  gap: 12px;
  justify-content: space-between;
  margin-bottom: 25px;
}

.select-row div {
  flex: 1;
  display: flex;
  flex-direction: column;
}

label {
  font-size: 0.85rem;
  color: #bbb;
  margin-bottom: 6px;
  text-align: left;
}

select {
  padding: 10px;
  font-size: 1rem;
  border-radius: 10px;
  border: 2px solid #00eaff;
  background-color: #1c1c2b;
  color: #fff;
  transition: border-color 0.3s;
}

select:focus {
  outline: none;
  border-color: #00c6ff;
}

.convert-btn {
  width: 100%;
  padding: 12px;
  font-size: 1rem;
  background: linear-gradient(to right, #00eaff, #007bff);
  color: #000;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  transition: background 0.3s ease, transform 0.2s ease;
  font-weight: bold;
}

.convert-btn:hover {
  background: linear-gradient(to right, #00c6ff, #0056b3);
  transform: translateY(-2px);
}

.result-output {
  margin-top: 25px;
  font-size: 1.5rem;
  font-weight: bold;
  color: #00eaff;
  background-color: #111827;
  padding: 15px;
  border-radius: 10px;
  box-shadow: inset 0 0 10px rgba(0,255,255,0.2);
  min-height: 1.5em;
}

footer {
  position: fixed;
  bottom: 15px;
  width: 100%;
  text-align: center;
  font-size: 0.85rem;
  color: #ddd;
  font-weight: 400;
  z-index: 10;
}

footer a {
  color: #00eaff;
  text-decoration: none;
  font-weight: 600;
}

footer a:hover {
  text-decoration: none;
  color: white;
}

@media (max-width: 480px) {
  .converter-container {
    padding: 25px;
    border-radius: 15px;
  }

  h1 {
    font-size: 1.6rem;
  }

  .input-value,
  select,
  .convert-btn {
    font-size: 0.95rem;
    padding: 10px;
  }

  .result-output {
    font-size: 1.2rem;
  }
}

@media (max-height: 600px) {
  footer {
    position: static;
    margin-top: 20px;
  }

  body {
    justify-content: flex-start;
  }
}