/* ================= Global Styles ================= */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Arial', sans-serif;
  background: linear-gradient(to right, #74ebd5, #ACB6E5);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  align-items: center;
  justify-content: flex-start;
  padding: 20px;
  color: #333;
}

h1 {
  text-align: center;
  color: #fff;
  margin-bottom: 10px;
  text-shadow: 2px 2px 5px rgba(0,0,0,0.3);
}

p.description {
  text-align: center;
  max-width: 500px;
  color: #fff;
  margin-bottom: 20px;
  font-size: 14px;
}

/* ================= Card Layout ================= */
.calculator-card {
  background-color: rgba(255, 255, 255, 0.95);
  padding: 30px 40px;
  border-radius: 15px;
  box-shadow: 0px 8px 20px rgba(0,0,0,0.2);
  max-width: 400px;
  width: 90%;
  text-align: center;
  margin-bottom: 30px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.calculator-card:hover {
  transform: translateY(-5px);
  box-shadow: 0px 12px 25px rgba(0,0,0,0.3);
}

/* ================= Inputs & Buttons ================= */
input[type=number], select {
  width: 80%;
  padding: 12px;
  margin: 10px 0;
  border-radius: 8px;
  border: 1px solid #ccc;
  font-size: 16px;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

input[type=number]:focus, select:focus {
  outline: none;
  border-color: #4CAF50;
  box-shadow: 0 0 5px rgba(76, 175, 80, 0.5);
}

button {
  padding: 12px 25px;
  margin-top: 10px;
  background-color: #4CAF50;
  color: white;
  font-size: 16px;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: 0.3s;
}

button:hover {
  background-color: #45a049;
  transform: scale(1.03);
}

/* ================= Results ================= */
#bmiResult, #ageResult, #calorieResult, #recommendation, #advice, #targetWeightInfo {
  margin-top: 20px;
  font-size: 18px;
  font-weight: bold;
  line-height: 1.4;
}

/* BMI Colors */
.underweight { color: #3498db; }
.normal { color: #27ae60; }
.overweight { color: #f39c12; }
.obese { color: #e74c3c; }

/* ================= Footer ================= */
footer {
  margin-top: 40px;
  padding: 15px;
  text-align: center;
  color: #fff;
  font-size: 14px;
}

footer a {
  color: white;
  text-decoration: none;
  transition: 0.3s;
}

footer a:hover {
  text-decoration: underline;
}

/* ================= Responsive Design ================= */
@media (max-width: 500px) {
  .calculator-card {
    padding: 20px;
  }

  input[type=number], select {
    width: 90%;
  }

  h1 {
    font-size: 24px;
  }

  #bmiResult, #ageResult, #calorieResult, #recommendation, #advice, #targetWeightInfo {
    font-size: 16px;
  }
}

/* ================= Optional Dark Mode ================= */
body.dark-mode {
  background: linear-gradient(to right, #2c3e50, #34495e);
  color: #ecf0f1;
}

body.dark-mode .calculator-card {
  background-color: rgba(44, 62, 80, 0.95);
  box-shadow: 0px 8px 20px rgba(0,0,0,0.5);
}

body.dark-mode input[type=number], body.dark-mode select {
  background-color: #ecf0f1;
  color: #2c3e50;
}

body.dark-mode button {
  background-color: #3498db;
}

body.dark-mode button:hover {
  background-color: #2980b9;
}