:root {
  --bg: #1a1a1a;
  --card: #2c2c2c;
  --text: #f5f5f5;
  --muted: #b0b0b0;
  --accent: #6c6c6c;
  --white: #ffffff;
}

body {
  margin: 0;
  font-family: "Segoe UI", Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

/* ===== HEADER ===== */
.top-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.5rem;
  border-bottom: 2px solid var(--accent);
  position: sticky;
  top: 0;
  background: var(--bg);
  z-index: 100;
}

.brand {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--white);
}

.links {
  display: flex;
  align-items: center;
}

.links a {
  color: var(--muted);
  text-decoration: none;
  margin-left: 1rem;
  transition: color 0.3s;
}

#auth-btn {
  margin-left: 1.5rem; /* adds space before the Sign In button */
}

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

/* ===== HERO ===== */
.hero {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  padding: 5rem 1rem;
  max-width: 1100px;
  margin: auto;
  gap: 2rem;
}

.hero-text {
  flex: 1 1 45%;
}

.hero-text h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.hero-text p {
  color: var(--muted);
  margin-bottom: 2rem;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
}

.hero-image {
  flex: 1 1 45%;
  text-align: center;
}

.hero-image img {
  width: 100%;
  max-width: 480px;
  border-radius: 1rem;
  box-shadow: 0 4px 15px rgba(0,0,0,0.4);
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-block;
  padding: 0.9rem 2rem;
  border-radius: 9999px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  cursor: pointer;
  border: none;
}

.primary {
  background: var(--card);
  color: var(--white);
}

.primary:hover {
  background: var(--accent);
}

.secondary {
  border: 2px solid var(--accent);
  color: var(--muted);
  background: transparent;
}

.secondary:hover {
  border-color: var(--white);
  color: var(--white);
}

.small {
  padding: 0.5rem 1.2rem;
  font-size: 0.9rem;
}

.full {
  width: 100%;
}

.large {
  padding: 1.1rem 3rem;
  font-size: 1.1rem;
}

/* ===== GRID & CARDS ===== */
.section {
  padding: 4rem 1rem;
  text-align: center;
  max-width: 1100px;
  margin: auto;
}

.grid {
  display: grid;
  gap: 2rem;
  margin-top: 2rem;
}

.three {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.four {
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}

.card {
  background: var(--card);
  padding: 2rem;
  border-radius: 1rem;
  box-shadow: 0 4px 8px rgba(0,0,0,0.3);
  transition: transform 0.3s;
}

.card:hover {
  transform: translateY(-5px);
}

/* ===== ABOUT / CTA ===== */
.about {
  padding-top: 5rem;   /* adds space above */
  padding-bottom: 5rem; /* adds space below */
}

.about p {
  max-width: 800px;
  margin: 1rem auto 0 auto;
  color: var(--muted);
  line-height: 1.8;
}

.cta h2 {
  margin-bottom: 2rem;
  font-size: 2rem;
}

/* ===== FOOTER ===== */
footer {
  text-align: center;
  border-top: 2px solid var(--accent);
  padding: 2rem 1rem;
  font-size: 0.9rem;
  color: var(--muted);
}

/* ===== MODAL (SIGN IN) ===== */
.modal {
  display: none;
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0, 0, 0, 0.8);
  justify-content: center;
  align-items: center;
}

.modal-content {
  background: var(--card);
  padding: 2rem;
  border-radius: 1rem;
  width: 90%;
  max-width: 350px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.4);
  text-align: center;
}

.modal-content h2 {
  margin-bottom: 1rem;
}

.modal-content input {
  width: 100%;
  padding: 0.8rem;
  margin: 0.5rem 0;
  border-radius: 0.5rem;
  border: none;
  outline: none;
  font-size: 1rem;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .hero {
    flex-direction: column;
    text-align: center;
  }
  .hero-text, .hero-image {
    flex: 1 1 100%;
  }
  .grid.three, .grid.four {
    grid-template-columns: 1fr;
  }
  .hero-buttons {
    justify-content: center;
  }
}