:root {
  --primary-color: #1a73e8;
  --primary-dark: #0f4cbd;
  --background-color: #f5f7fb;
  --text-color: #1f2933;
  --muted-text: #4a5568;
  --border-radius: 12px;
  --max-width: 900px;
  --font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-family);
  background-color: var(--background-color);
  color: var(--text-color);
  line-height: 1.6;
}

a {
  color: var(--primary-color);
  text-decoration: none;
}

a:hover,
a:focus {
  text-decoration: underline;
}

header {
  background-color: #ffffff;
  border-bottom: 1px solid rgba(15, 76, 189, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
}

.container {
  margin: 0 auto;
  max-width: var(--max-width);
  padding: 0 1.5rem;
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 0;
  gap: 1.5rem;
}

.brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-dark);
  margin: 0;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 1rem;
}

nav a {
  display: block;
  padding: 0.5rem 1rem;
  border-radius: 999px;
  font-weight: 600;
  color: var(--muted-text);
  transition: background-color 0.2s ease, color 0.2s ease;
}

nav a:hover,
nav a:focus {
  background-color: rgba(26, 115, 232, 0.1);
  color: var(--primary-dark);
}

nav a.active {
  background-color: var(--primary-color);
  color: #ffffff;
}

main {
  padding: 3rem 0 4rem;
}

main .container {
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.hero {
  background: linear-gradient(135deg, rgba(26, 115, 232, 0.08), rgba(15, 76, 189, 0.08));
  border-radius: var(--border-radius);
  padding: 3rem;
  text-align: center;
}

.hero h1 {
  margin-top: 0;
  font-size: 2.4rem;
  line-height: 1.2;
}

.hero p {
  color: var(--muted-text);
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
}

.button-group {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 1rem;
}

.button {
  display: inline-block;
  padding: 0.75rem 1.75rem;
  border-radius: 999px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  background-color: var(--primary-color);
  color: #ffffff;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.button.secondary {
  background-color: transparent;
  border: 2px solid var(--primary-color);
  color: var(--primary-dark);
}

.button:hover,
.button:focus {
  background-color: var(--primary-dark);
  color: #ffffff;
  transform: translateY(-1px);
}

.button.secondary:hover,
.button.secondary:focus {
  background-color: rgba(26, 115, 232, 0.1);
  color: var(--primary-dark);
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background-color: #ffffff;
  border-radius: var(--border-radius);
  padding: 1.75rem;
  box-shadow: 0 15px 35px rgba(15, 76, 189, 0.08);
}

.feature-card h3 {
  margin-top: 0;
  font-size: 1.3rem;
}

.feature-card p {
  color: var(--muted-text);
}

.section-title {
  margin: 0;
  font-size: 1.8rem;
}

.cta {
  background-color: #ffffff;
  border-radius: var(--border-radius);
  padding: 2.5rem;
  text-align: center;
  box-shadow: 0 15px 35px rgba(15, 76, 189, 0.08);
}

.cta p {
  color: var(--muted-text);
  margin-bottom: 1.5rem;
}

footer {
  background-color: #0f172a;
  color: #e2e8f0;
  padding: 2rem 0;
}

footer .footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

footer a {
  color: #cbd5f5;
}

footer a:hover,
footer a:focus {
  color: #ffffff;
}

.content-section {
  background-color: #ffffff;
  border-radius: var(--border-radius);
  padding: 2rem;
  box-shadow: 0 10px 25px rgba(15, 76, 189, 0.05);
}

.content-section h1,
.content-section h2,
.content-section h3 {
  color: var(--primary-dark);
}

.content-section p,
.content-section li {
  color: var(--muted-text);
}

.content-section ol,
.content-section ul {
  padding-left: 1.25rem;
}

.content-section li + li {
  margin-top: 0.5rem;
}

form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

label {
  font-weight: 600;
}

input[type="email"],
input[type="password"],
textarea {
  padding: 0.75rem;
  border: 1px solid rgba(15, 76, 189, 0.2);
  border-radius: 8px;
  font-size: 1rem;
  font-family: inherit;
}

input[type="email"]:focus,
input[type="password"]:focus,
textarea:focus {
  outline: 2px solid rgba(26, 115, 232, 0.4);
  border-color: transparent;
}

.alert-text {
  font-size: 0.95rem;
  color: var(--muted-text);
}

.back-link {
  display: inline-block;
  margin-bottom: 1.5rem;
}

@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    align-items: flex-start;
  }

  nav ul {
    width: 100%;
    flex-direction: column;
  }

  nav a {
    width: 100%;
    text-align: center;
  }

  .hero {
    padding: 2.5rem 2rem;
  }

  .hero h1 {
    font-size: 2rem;
  }

  main {
    padding: 2rem 0 3rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}