/* ============================================================
   Design Tokens
   ============================================================ */
:root {
  /* Colors */
  --color-bg:           #0a0a0f;
  --color-surface:      #13131a;
  --color-surface-2:    #1a1a24;
  --color-border:       #1e1e2e;
  --color-text:         #e2e2f0;
  --color-muted:        #8888aa;
  --color-accent:       #7c6af7;
  --color-accent-hover: #9b8dff;
  --color-danger:       #f76a6a;
  --color-success:      #6af7a8;

  /* Typography */
  --font-sans:   system-ui, -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono:   "JetBrains Mono", "Fira Code", "Cascadia Code", monospace;
  --text-xs:     0.75rem;
  --text-sm:     0.875rem;
  --text-base:   1rem;
  --text-lg:     1.125rem;
  --text-xl:     1.25rem;
  --text-2xl:    1.5rem;
  --text-3xl:    1.875rem;
  --text-4xl:    2.25rem;
  --text-5xl:    3rem;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Radii */
  --radius-sm: 0.25rem;
  --radius:    0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.4);
  --shadow:    0 4px 16px rgba(0,0,0,0.5);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.6);

  /* Transitions */
  --ease: 0.2s ease;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

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

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

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--ease);
}
a:hover { color: var(--color-accent-hover); }
a:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ============================================================
   Layout Utilities
   ============================================================ */
.container {
  width: 100%;
  max-width: 1120px;
  margin-inline: auto;
  padding-inline: var(--space-6);
}

/* ============================================================
   Buttons
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 600;
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition: background-color var(--ease), color var(--ease),
              border-color var(--ease), opacity var(--ease);
  white-space: nowrap;
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background-color: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
}
.btn-primary:hover:not(:disabled) {
  background-color: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
  color: #fff;
}

.btn-outline {
  background-color: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}
.btn-outline:hover:not(:disabled) {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.btn-ghost {
  background-color: transparent;
  color: var(--color-muted);
  border-color: transparent;
}
.btn-ghost:hover:not(:disabled) {
  color: var(--color-text);
}

.btn-full {
  width: 100%;
}

.btn-lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-base);
}

/* ============================================================
   Form Controls
   ============================================================ */
.input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  color: var(--color-text);
  background-color: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color var(--ease), box-shadow var(--ease);
  outline: none;
}
.input::placeholder { color: var(--color-muted); }
.input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(124,106,247,0.2);
}

.select {
  appearance: none;
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  color: var(--color-text);
  background-color: var(--color-surface-2);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  outline: none;
  cursor: pointer;
}
.select:focus { border-color: var(--color-accent); }

label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-muted);
  margin-bottom: var(--space-2);
}

/* ============================================================
   Navigation
   ============================================================ */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) var(--space-6);
  background-color: rgba(10,10,15,0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav__logo {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
}
.nav__logo:hover { color: var(--color-accent); }

.nav__actions { display: flex; gap: var(--space-3); align-items: center; }

/* ============================================================
   Hero
   ============================================================ */
.hero {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-24) var(--space-6);
  text-align: center;
}

.hero__content { max-width: 720px; }

.hero__headline {
  font-size: clamp(var(--text-3xl), 6vw, var(--text-5xl));
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, var(--color-text) 40%, var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-6);
}

.hero__subheadline {
  font-size: var(--text-lg);
  color: var(--color-muted);
  max-width: 560px;
  margin-inline: auto;
  margin-bottom: var(--space-10);
}

.hero__cta {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
}

/* ============================================================
   Features
   ============================================================ */
.features {
  padding: var(--space-20) var(--space-6);
  border-top: 1px solid var(--color-border);
}

.features__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--space-6);
  max-width: 1120px;
  margin-inline: auto;
}

.feature-card {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: border-color var(--ease), box-shadow var(--ease);
}
.feature-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 1px var(--color-accent), var(--shadow);
}

.feature-card__icon {
  font-size: var(--text-3xl);
  margin-bottom: var(--space-4);
}

.feature-card__title {
  font-size: var(--text-lg);
  font-weight: 700;
  margin-bottom: var(--space-3);
  color: var(--color-text);
}

.feature-card__description {
  font-size: var(--text-sm);
  color: var(--color-muted);
  line-height: 1.7;
}

/* ============================================================
   Footer
   ============================================================ */
.footer {
  padding: var(--space-8) var(--space-6);
  border-top: 1px solid var(--color-border);
  text-align: center;
}

.footer__copy {
  font-size: var(--text-sm);
  color: var(--color-muted);
}

/* ============================================================
   Modal
   ============================================================ */
.modal-wrapper {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-6);
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background-color: rgba(0,0,0,0.7);
  backdrop-filter: blur(4px);
  cursor: pointer;
}

.modal {
  position: relative;
  z-index: 1;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  width: 100%;
  max-width: 440px;
  box-shadow: var(--shadow-lg);
}

.modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--space-6);
}

.modal__title {
  font-size: var(--text-2xl);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.modal__close {
  background: none;
  border: none;
  color: var(--color-muted);
  font-size: var(--text-xl);
  cursor: pointer;
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  line-height: 1;
  transition: color var(--ease);
}
.modal__close:hover { color: var(--color-text); }
.modal__close:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.modal__error {
  background-color: rgba(247,106,106,0.1);
  border: 1px solid rgba(247,106,106,0.3);
  color: var(--color-danger);
  font-size: var(--text-sm);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius);
  margin-bottom: var(--space-4);
}

.modal__oauth {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin-bottom: var(--space-5);
}

.modal__divider {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-block: var(--space-5);
  color: var(--color-muted);
  font-size: var(--text-sm);
}
.modal__divider::before,
.modal__divider::after {
  content: "";
  flex: 1;
  height: 1px;
  background-color: var(--color-border);
}

.modal__magic-link {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 640px) {
  .nav { padding: var(--space-3) var(--space-4); }
  .hero { padding: var(--space-16) var(--space-4); }
  .hero__cta { flex-direction: column; align-items: stretch; }
  .features { padding: var(--space-12) var(--space-4); }
  .modal { padding: var(--space-6); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition-duration: 0.01ms !important; }
}