/* Google Font */
@import url('https://fonts.googleapis.com/css2?family=Montserrat:wght@400;500;600;700&display=swap');

/* CSS Variables for Theme */
:root {
  --primary-bg: #f8fbfd;
  --primary-color: #2079b0;
  --accent-color: #4ca1af;
  --light-accent: #e3f2fd;
  --text-color: #1f2d3d;
  --white: #ffffff;
  --shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

/* Reset and Base Styling */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html, body {
  font-family: 'Montserrat', sans-serif;
  background-color: var(--primary-bg);
  color: var(--text-color);
  scroll-behavior: smooth;
  line-height: 1.6;
}

/* Typography */
h1, h2, h3, h4, h5 {
  font-weight: 600;
  color: var(--text-color);
  margin-bottom: 1rem;
}

h1 { font-size: 2.2rem; }
h2 { font-size: 1.8rem; }
h3 { font-size: 1.5rem; }

/* Buttons */
button {
  background-color: var(--primary-color);
  color: var(--white);
  padding: 12px 24px;
  border: none;
  border-radius: 8px;
  font-weight: 500;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: background 0.3s ease, transform 0.2s ease;
}

button:hover {
  background-color: var(--accent-color);
  transform: translateY(-2px);
}

/* Containers and Layout */
.container {
  width: 90%;
  max-width: 1200px;
  margin: auto;
  padding: 2rem 0;
}

.section {
  margin-top: 3rem;
  margin-bottom: 3rem;
}

/* Card / Module Box */
.card {
  background-color: var(--white);
  border-radius: 12px;
  box-shadow: var(--shadow);
  padding: 2rem;
  transition: transform 0.3s ease;
}

.card:hover {
  transform: translateY(-4px);
}

/* Instruments Panel */
.instrument-panel {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

/* Input Fields */
input, select, textarea {
  width: 100%;
  padding: 10px 14px;
  border-radius: 6px;
  border: 1px solid #ccc;
  margin-top: 0.5rem;
  margin-bottom: 1rem;
  font-size: 1rem;
  font-family: 'Montserrat', sans-serif;
}

/* Labels */
label {
  font-weight: 500;
  margin-bottom: 0.3rem;
  display: inline-block;
}

/* Navigation */
.navbar {
  background-color: var(--white);
  padding: 1rem 2rem;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  position: sticky;
  top: 0;
  z-index: 10;
}

.navbar ul {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}

.navbar a {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  transition: color 0.2s ease;
}

.navbar a:hover {
  color: var(--primary-color);
}

/* Footer */
.footer {
  background-color: var(--light-accent);
  color: #333;
  text-align: center;
  padding: 1rem;
  font-size: 0.9rem;
}

/* Graph and Data Panels */
.graph-container {
  margin-top: 2rem;
  background: var(--white);
  padding: 1.5rem;
  border-radius: 10px;
  box-shadow: var(--shadow);
}

/* Utility Classes */
.text-center { text-align: center; }
.mt-2 { margin-top: 1rem; }
.mt-4 { margin-top: 2rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-4 { margin-bottom: 2rem; }

.flex {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
}

/* Responsive Tweaks */
@media (max-width: 768px) {
  .navbar ul {
    flex-direction: column;
    align-items: flex-start;
  }

  h1 {
    font-size: 1.8rem;
  }
}