/* Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 18px; /* Slightly larger base */
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen,
    Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
  background-color: #fafbfc;
  color: #1a1a1a;
  line-height: 1.65;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Site Header */
.site-header {
  position: sticky;
  top: 0;
  background: #ffffff;
  border-bottom: 1px solid #ddd;
  padding: 1.25rem 2.5rem;
  display: flex;
  align-items: center;
  z-index: 10;
  box-shadow: 0 2px 4px rgb(0 0 0 / 0.05);
}

/* Logo */
.logo-link {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  color: #00aaff;
  font-weight: 700;
  font-size: 1.65rem;
  text-decoration: none;
  user-select: none;
  transition: color 0.3s ease;
}

.logo-link:hover,
.logo-link:focus {
  color: #008ecc;
  outline: none;
}

.logo-link svg {
  height: 40px;
  width: 40px;
  fill: currentColor;
  flex-shrink: 0;
}

/* Main container */
main {
  flex-grow: 1;
  max-width: 960px;
  margin: 3rem auto;
  padding: 0 2rem;
}

/* Sections */
section {
  margin-bottom: 4rem;
}

h1 {
  font-size: 2.75rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: #222;
}

h2 {
  font-size: 2.0rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: #333;
}

/* Paragraphs */
p {
  font-size: 1.125rem;
  margin-top: 0;
  margin-bottom: 1.5rem;
  color: #444;
  max-width: 600px;
  line-height: 1.7;
}

/* Buttons */
button,
.cta-button {
  background-color: #00aaff;
  color: #fff;
  border: none;
  padding: 0.85em 2em;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 700;
  font-size: 1.125rem;
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
  box-shadow: 0 3px 6px rgba(0, 170, 255, 0.4);
}

button:hover,
.cta-button:hover,
button:focus,
.cta-button:focus {
  background-color: #008ecc;
  box-shadow: 0 6px 12px rgba(0, 142, 204, 0.6);
  outline: none;
}

/* Forms */
.signup-form {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  max-width: 420px;
  margin: 1rem 0;
}

.signup-form label {
  font-weight: 600;
  font-size: 1rem;
  color: #222;
}

.signup-form input[type="email"] {
  padding: 0.9em 1em;
  border: 2px solid #ccc;
  border-radius: 8px;
  font-size: 1.125rem;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
  font-weight: 400;
  color: #222;
}

.signup-form input[type="email"]:focus {
  border-color: #00aaff;
  box-shadow: 0 0 6px rgba(0, 170, 255, 0.5);
  outline: none;
}

/* Footer */
.site-footer {
  background-color: #fff;
  border-top: 1px solid #ddd;
  text-align: center;
  padding: 2rem 1rem;
  font-size: 0.95rem;
  color: #666;
  user-select: none;
}

/* Utility */
.mt-0 {
  margin-top: 0 !important;
}

.mb-0 {
  margin-bottom: 0 !important;
}