/* Reset & Base */
html {
  box-sizing: border-box;
  font-size: 62.5%; /* 1rem = 10px */
}

*, *::before, *::after {
  box-sizing: inherit;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Segoe UI', 'Helvetica Neue', sans-serif;
  background-color: #f0fff4; /* light green background */
  color: #1b321b;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* Variables */
:root {
  --green: #8ae68a;
  --green-dark: #4cd64c;
  --green-hover: #45b845;
  --green-accent: #e5fcec;
  --text-dark: #1b321b;
  --card-bg: #ffffff;
  --card-shadow: rgba(0, 0, 0, 0.1);
  --radius: 12px;
  --transition: 0.3s;
}

/* Logo */
.logo-img {
  width: 64px;
  height: 64px;
  object-fit: contain;
}

/* Header */
header {
  width: 100%;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 6px var(--card-shadow);
}

/* Header Logo */
.header-logo-container {
  display: flex;
  align-items: center;
}

/* Nav Bar */
nav ul {
  list-style: none;
  display: flex;
  gap: 2rem;
  margin: 0;
  padding: 0;
}

nav a {
  text-decoration: none;
  color: var(--text-dark);
  font-weight: 600;
  font-size: 1.6rem;
  transition: color var(--transition);
}

nav a:hover {
  color: var(--green-hover);
}

/* Main Content */
main {
  padding: 2rem;
  width: 100%;
  max-width: 1200px;
  flex: 1;
}

/* Footer (optional) */
footer {
  background-color: #dfffe1;
  padding: 1.5rem;
  text-align: center;
  font-size: 1.4rem;
  color: #2c4c2c;
  width: 100%;
}

/* Headings */
h1, h2, h3 {
  color: var(--green-dark);
  margin-bottom: 1rem;
}

h1 {
  font-size: 3.2rem;
}
h2 {
  font-size: 2.4rem;
}
h3 {
  font-size: 1.8rem;
}

/* Paragraph */
p {
  font-size: 1.6rem;
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

/* Buttons */
.btn {
  padding: 0.8rem 1.6rem;
  background-color: rgb(4, 216, 4);
  color: #fff;
  border: none;
  border-radius: var(--radius);
  font-size: 1.6rem;
  font-weight: bold;
  cursor: pointer;
  transition: background-color var(--transition);
  text-decoration: none;
  display: inline-block;
}

.btn:hover {
  background-color: var(--green-hover);
}

/* Cards */
.card {
  background-color: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: 0 4px 8px var(--card-shadow);
  padding: 2rem;
  margin: 2rem 0;
  text-align: center;
  transition: transform 0.2s;
}

.card:hover {
  transform: scale(1.02);
}

/* Utility Classes */
.text-center {
  text-align: center;
}

.mt-2 {
  margin-top: 2rem;
}

.mb-2 {
  margin-bottom: 2rem;
}

/* Image Container */
.logo-container {
  display: flex;
  justify-content: center;
  margin: 2rem 0;
}

.logo-container img {
  width: 100%;
  max-width: 300px;
  height: auto;
  object-fit: contain;
}

/* Responsive Layout */
@media (max-width: 768px) {
  nav ul {
    flex-direction: column;
    gap: 1rem;
  }

  header {
    flex-direction: column;
    align-items: flex-start;
  }

  .logo-img {
    width: 48px;
    height: 48px;
  }
}