/* ===== Reset & Base ===== */
*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --color-bg: #0f1117;
  --color-surface: #1a1d27;
  --color-primary: #6c63ff;
  --color-primary-hover: #5a52e0;
  --color-text: #e4e4e7;
  --color-text-muted: #a1a1aa;
  --color-border: #27272a;
  --font-sans: "Inter", system-ui, -apple-system, sans-serif;
  --radius: 8px;
  --max-width: 1100px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

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

/* ===== Utilities ===== */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
}

.btn {
  display: inline-block;
  padding: 0.75rem 1.75rem;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  border: none;
  transition: background 0.2s, transform 0.2s;
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}

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

.section-title {
  font-size: 2rem;
  margin-bottom: 2rem;
  text-align: center;
}

/* ===== Header / Nav ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(15, 17, 23, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  transition: color 0.2s;
}

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

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-text);
  transition: transform 0.3s, opacity 0.3s;
}

/* ===== Hero ===== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 6rem 1.5rem 4rem;
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 1.25rem;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--color-text-muted);
  max-width: 500px;
  margin: 0 auto 2rem;
}

/* ===== Features ===== */
.features {
  padding: 6rem 0;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
  text-align: center;
  transition: transform 0.2s, border-color 0.2s;
}

.feature-card:hover {
  transform: translateY(-4px);
  border-color: var(--color-primary);
}

.feature-icon {
  font-size: 2.5rem;
  margin-bottom: 1rem;
}

.feature-card h3 {
  margin-bottom: 0.5rem;
  font-size: 1.25rem;
}

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

/* ===== About ===== */
.about {
  padding: 6rem 0;
  text-align: center;
}

.about p {
  max-width: 600px;
  margin: 0 auto;
  color: var(--color-text-muted);
  font-size: 1.1rem;
}

/* ===== Contact ===== */
.contact {
  padding: 6rem 0;
}

.contact-form {
  max-width: 520px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.form-group label {
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.form-group input,
.form-group textarea {
  padding: 0.75rem 1rem;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  font-family: inherit;
  font-size: 1rem;
  outline: none;
  transition: border-color 0.2s;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--color-primary);
}

/* ===== Footer ===== */
.footer {
  padding: 2rem 0;
  text-align: center;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

/* ===== Mobile ===== */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    height: 100vh;
    width: 260px;
    background: var(--color-surface);
    flex-direction: column;
    padding: 5rem 2rem 2rem;
    gap: 1.5rem;
    transition: right 0.3s;
    border-left: 1px solid var(--color-border);
  }

  .nav-links.open {
    right: 0;
  }

  .nav-links a {
    font-size: 1.1rem;
  }
}