/* Reset & Variables */
:root {
  --primary-color: #3A76F0;
  --primary-hover: #2d5dc2;
  --bg-color: #ffffff;
  --bg-secondary: #f4f5f7;
  --text-primary: #1A1A1A;
  --text-secondary: #5f6368;
  --footer-bg: #1B1B1B;
  --hero-bg: #C5CAFF;
  --border-radius: 12px;
  --border-radius-lg: 24px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-color);
  -webkit-font-smoothing: antialiased;
}

a {
  text-decoration: none;
  color: inherit;
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 16px;
}

h1 { font-size: 3.5rem; letter-spacing: -0.02em; }
h2 { font-size: 2.5rem; letter-spacing: -0.01em; }
h3 { font-size: 1.75rem; }

p {
  margin-bottom: 16px;
  font-size: 1.125rem;
}

/* Header */
header {
  position: sticky;
  top: 0;
  background-color: var(--bg-color);
  z-index: 1000;
  padding: 16px 0;
}

.header-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-color);
}

.logo img {
  width: 40px;
  height: 40px;
}

.nav-links {
  display: flex;
  gap: 24px;
  align-items: center;
}

.nav-links a {
  font-weight: 600;
  font-size: 1rem;
  transition: color 0.2s;
}

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

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 8px;
  font-weight: 600;
  text-align: center;
  transition: all 0.2s;
  cursor: pointer;
  border: 2px solid transparent;
}

.btn-primary {
  background-color: var(--bg-color);
  color: var(--primary-color);
  border-color: var(--primary-color);
}

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

.btn-solid {
  background-color: var(--primary-color);
  color: var(--bg-color);
}

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

/* Footer */
footer {
  background-color: var(--footer-bg);
  color: #fff;
  padding: 64px 0 32px;
  margin-top: 64px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 48px;
}

.footer-col h4 {
  font-size: 1.125rem;
  margin-bottom: 24px;
  color: #fff;
}

.footer-col ul li {
  margin-bottom: 12px;
}

.footer-col ul a {
  color: #a0a0a0;
  transition: color 0.2s;
}

.footer-col ul a:hover {
  color: #fff;
}

.footer-bottom {
  border-top: 1px solid #333;
  padding-top: 32px;
  display: flex;
  justify-content: space-between;
  color: #a0a0a0;
  font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 992px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .nav-links {
    display: none; /* In a real project, this would be a hamburger menu */
  }
}

@media (max-width: 768px) {
  h1 { font-size: 2.5rem; }
  h2 { font-size: 2rem; }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}