/* ========================================
   Design System — Curso Claude Code
   Light Editorial Técnico
   ======================================== */

:root {
  /* === Cores ============================================ */
  --paper:        #F7F5EF;
  --paper-sunk:   #EFEBE0;
  --paper-raised: #FFFFFF;
  --paper-hover:  #F1EDE3;

  --ink:          #1B1A17;
  --ink-soft:     #3D3B36;
  --ink-mute:     #6F6C63;

  --rule:         rgba(27, 26, 23, 0.12);
  --rule-strong:  rgba(27, 26, 23, 0.22);

  --rust:         #B8431F;
  --rust-deep:    #8A2F12;
  --rust-wash:    #F4E4DC;

  --success:      #2D6A4F;
  --danger:       #9D2F2F;

  /* === Tipografia ======================================= */
  --font-sans: 'Geist', 'Inter Tight', ui-sans-serif, system-ui, -apple-system, sans-serif;
  --font-mono: 'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, monospace;

  --fs-12: 0.75rem;
  --fs-14: 0.875rem;
  --fs-16: 1rem;
  --fs-18: 1.125rem;
  --fs-22: 1.375rem;
  --fs-28: 1.75rem;
  --fs-36: 2.25rem;
  --fs-52: 3.25rem;

  --lh-tight:  1.05;
  --lh-snug:   1.2;
  --lh-normal: 1.5;
  --lh-loose:  1.7;

  --track-tight: -0.02em;
  --track-flat:   0;
  --track-wide:   0.08em;

  /* === Espaçamento ====================================== */
  --space-xs:  0.25rem;
  --space-sm:  0.5rem;
  --space-md:  1rem;
  --space-lg:  1.5rem;
  --space-xl:  2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* === Radius =========================================== */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;
  --radius-xl: 14px;

  /* === Shadows ========================================== */
  --shadow-sm: 0 1px 0 rgba(27, 26, 23, 0.04);
  --shadow-md: 0 1px 2px rgba(27, 26, 23, 0.06), 0 2px 8px rgba(27, 26, 23, 0.04);
  --shadow-lg: 0 2px 4px rgba(27, 26, 23, 0.06), 0 12px 24px rgba(27, 26, 23, 0.08);

  /* === Motion =========================================== */
  --ease-snap:        cubic-bezier(0.2, 0, 0, 1);
  --duration-fast:    120ms;
  --duration-normal:  200ms;
  --duration-slow:    400ms;
}

/* ========================================
   Reset & Base
   ======================================== */

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  background: var(--paper);
  color: var(--ink);
  line-height: var(--lh-normal);
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: var(--ink);
  text-decoration: underline;
  text-decoration-color: var(--rule-strong);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: text-decoration-color var(--duration-fast) var(--ease-snap),
              color                 var(--duration-fast) var(--ease-snap);
}

a:hover {
  text-decoration-color: var(--rust);
}

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

::selection {
  background: var(--rust-wash);
  color: var(--ink);
}

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

/* ========================================
   Utilities
   ======================================== */

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

.sr-only,
.skip-link {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
  white-space: nowrap;
}

.skip-link:focus {
  position: fixed;
  top: var(--space-md);
  left: var(--space-md);
  width: auto;
  height: auto;
  padding: var(--space-sm) var(--space-md);
  background: var(--ink);
  color: var(--paper);
  text-decoration: none;
  clip: auto;
  z-index: 200;
  border-radius: var(--radius-sm);
}

/* ========================================
   Navigation
   ======================================== */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: var(--space-md) 0;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  background: rgba(247, 245, 239, 0.85);
  border-bottom: 1px solid transparent;
  transition: border-color var(--duration-normal) var(--ease-snap),
              background-color var(--duration-normal) var(--ease-snap);
}

.nav.scrolled {
  border-bottom-color: var(--rule);
  background: rgba(247, 245, 239, 0.95);
}

.nav .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
}

.nav-logo {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  font-weight: 600;
  color: var(--ink);
  text-decoration: none;
  letter-spacing: var(--track-flat);
}

.nav-logo:hover {
  text-decoration: none;
  color: var(--ink);
}

.nav-logo .logo-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  background: var(--ink);
  color: var(--paper);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: 700;
}

.nav-logo .nav-locale {
  color: var(--ink-mute);
  font-weight: 400;
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: var(--ink);
  color: var(--paper);
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: var(--fs-14);
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--duration-fast) var(--ease-snap);
  min-height: 38px;
}

.nav-cta:hover {
  background: var(--rust-deep);
  color: var(--paper);
  text-decoration: none;
}

.nav-cta:focus-visible {
  outline: 2px solid var(--rust);
  outline-offset: 2px;
}

#user-greeting {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--ink-mute);
  letter-spacing: var(--track-wide);
  text-transform: uppercase;
}

/* ========================================
   Hero
   ======================================== */

.hero {
  padding: clamp(6rem, 12vw, 9rem) 0 var(--space-4xl);
  border-bottom: 1px solid var(--rule);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
  align-items: start;
}

@media (min-width: 1024px) {
  .hero-grid {
    grid-template-columns: minmax(0, 1.5fr) minmax(360px, 1fr);
    gap: 5rem;
  }
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: var(--track-wide);
  text-transform: uppercase;
  color: var(--ink-mute);
  margin-bottom: var(--space-xl);
}

.hero-eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--rust);
  border-radius: 50%;
  flex-shrink: 0;
}

.hero h1 {
  font-size: clamp(2rem, 5.5vw, var(--fs-52));
  font-weight: 600;
  line-height: var(--lh-tight);
  letter-spacing: var(--track-tight);
  margin: 0 0 var(--space-lg);
  max-width: 16ch;
}

.hero h1 .lede {
  color: var(--ink-mute);
  display: block;
}

.hero h1 .punch {
  color: var(--ink);
  display: block;
}

.hero-lead {
  font-size: var(--fs-18);
  line-height: var(--lh-loose);
  color: var(--ink-soft);
  max-width: 50ch;
  margin: 0 0 var(--space-2xl);
}

.hero-trust {
  list-style: none;
  padding: 0;
  margin: 0 0 var(--space-2xl);
  display: grid;
  gap: var(--space-sm);
}

.hero-trust li {
  display: flex;
  align-items: baseline;
  gap: var(--space-md);
  font-size: var(--fs-14);
  color: var(--ink-soft);
  line-height: var(--lh-normal);
}

.hero-trust li::before {
  content: "—";
  color: var(--rust);
  font-family: var(--font-mono);
  font-weight: 500;
  flex-shrink: 0;
}

.hero-cta-row {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
}

@media (min-width: 1024px) {
  .hero-cta-row {
    display: none;
  }
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 14px 24px;
  background: var(--ink);
  color: var(--paper);
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: var(--fs-16);
  font-weight: 600;
  cursor: pointer;
  text-decoration: none;
  transition: background var(--duration-fast) var(--ease-snap),
              transform  var(--duration-fast) var(--ease-snap);
  min-height: 48px;
}

.hero-cta:hover {
  background: var(--rust-deep);
  color: var(--paper);
  text-decoration: none;
}

.hero-cta:active {
  transform: translateY(1px);
}

.hero-cta:focus-visible {
  outline: 2px solid var(--rust);
  outline-offset: 3px;
}

.hero-cta-note {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--ink-mute);
  letter-spacing: var(--track-wide);
  text-transform: uppercase;
}

/* Form integrado no hero (desktop) */
.hero-form-card {
  display: none;
}

@media (min-width: 1024px) {
  .hero-form-card {
    display: block;
    position: sticky;
    top: calc(var(--space-4xl) + var(--space-lg));
  }
}

/* ========================================
   Section base
   ======================================== */

.section {
  padding: var(--space-4xl) 0;
  border-bottom: 1px solid var(--rule);
}

.section-header {
  margin-bottom: var(--space-2xl);
  max-width: 640px;
}

.section-tag {
  display: inline-block;
  font-size: var(--fs-12);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: var(--track-wide);
  color: var(--ink-mute);
  margin-bottom: var(--space-md);
  font-family: var(--font-mono);
}

.section-title {
  font-size: clamp(1.75rem, 3.5vw, var(--fs-36));
  font-weight: 600;
  letter-spacing: var(--track-tight);
  line-height: var(--lh-snug);
  color: var(--ink);
}

.section-title .accent {
  color: var(--rust);
}

.section-subtitle {
  color: var(--ink-soft);
  margin-top: var(--space-md);
  font-size: var(--fs-18);
  line-height: var(--lh-loose);
  max-width: 60ch;
}

/* ========================================
   Lessons — editorial list
   ======================================== */

.lessons-list {
  list-style: none;
  padding: 0;
  margin: 0;
  border-top: 1px solid var(--rule);
}

.lesson-row {
  display: grid;
  grid-template-columns: 40px 1fr auto 24px;
  align-items: center;
  gap: var(--space-lg);
  padding: var(--space-lg) var(--space-md);
  border-bottom: 1px solid var(--rule);
  color: var(--ink);
  text-decoration: none;
  position: relative;
  transition: background var(--duration-fast) var(--ease-snap);
}

.lesson-row::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: transparent;
  transition: background var(--duration-fast) var(--ease-snap);
}

.lesson-row:hover,
.lesson-row:focus-visible {
  background: var(--paper-hover);
  text-decoration: none;
}

.lesson-row:hover::before,
.lesson-row:focus-visible::before {
  background: var(--rust);
}

.lesson-row:hover .lesson-title {
  text-decoration: underline;
  text-decoration-color: var(--ink);
  text-underline-offset: 4px;
  text-decoration-thickness: 1px;
}

.lesson-row:focus-visible {
  outline: 2px solid var(--rust);
  outline-offset: -2px;
}

.lesson-num {
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  font-weight: 500;
  color: var(--ink-mute);
}

.lesson-title-wrap {
  display: flex;
  align-items: baseline;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.lesson-title {
  font-size: var(--fs-18);
  font-weight: 500;
  letter-spacing: var(--track-tight);
  color: var(--ink);
}

.lesson-flag {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: var(--track-wide);
  text-transform: uppercase;
  padding: 2px 6px;
  background: var(--rust-wash);
  color: var(--rust-deep);
  border-radius: 2px;
}

.lesson-time {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--ink-mute);
  letter-spacing: var(--track-wide);
  text-transform: uppercase;
  white-space: nowrap;
}

.lesson-arrow {
  font-family: var(--font-mono);
  color: var(--ink-mute);
  transition: transform var(--duration-fast) var(--ease-snap),
              color     var(--duration-fast) var(--ease-snap);
  text-align: right;
}

.lesson-row:hover .lesson-arrow {
  color: var(--rust);
  transform: translateX(3px);
}

@media (max-width: 600px) {
  .lesson-row {
    grid-template-columns: 32px 1fr 24px;
    gap: var(--space-md);
    padding: var(--space-md) var(--space-sm);
  }
  .lesson-time {
    grid-column: 2;
    grid-row: 2;
    margin-top: var(--space-xs);
  }
  .lesson-arrow {
    grid-row: 1 / 3;
    align-self: center;
  }
}

/* ========================================
   About / Terminal
   ======================================== */

.about-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-2xl);
  align-items: start;
}

@media (min-width: 900px) {
  .about-content {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
    gap: var(--space-3xl);
  }
}

.about-text p {
  color: var(--ink-soft);
  margin-top: var(--space-md);
  font-size: var(--fs-16);
  line-height: var(--lh-loose);
  max-width: 55ch;
}

.about-text p:first-of-type {
  margin-top: var(--space-xl);
}

.about-features {
  list-style: none;
  padding: 0;
  margin-top: var(--space-xl);
  display: grid;
  gap: var(--space-sm);
}

.about-features li {
  display: flex;
  align-items: baseline;
  gap: var(--space-md);
  color: var(--ink-soft);
  font-size: var(--fs-14);
  line-height: var(--lh-normal);
}

.about-features li::before {
  content: "—";
  color: var(--rust);
  font-family: var(--font-mono);
  flex-shrink: 0;
}

.about-features strong {
  color: var(--ink);
  font-weight: 600;
}

/* Terminal — único elemento dark da página */
.terminal {
  background: var(--ink);
  border-radius: var(--radius-lg);
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  line-height: var(--lh-loose);
  box-shadow: var(--shadow-lg);
}

.terminal-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-sm) var(--space-md);
  background: rgba(255, 255, 255, 0.04);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.terminal-dots {
  display: inline-flex;
  gap: 6px;
}

.terminal-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.18);
}

.terminal-path {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: rgba(247, 245, 239, 0.55);
}

.terminal-body {
  padding: var(--space-md) var(--space-lg);
  color: rgba(247, 245, 239, 0.88);
  overflow-x: auto;
}

.terminal-line {
  display: block;
  white-space: pre;
}

.terminal-prompt   { color: var(--rust); }
.terminal-command  { color: var(--paper); }
.terminal-output   { color: rgba(247, 245, 239, 0.6); }
.terminal-action   { color: rgba(247, 245, 239, 0.88); }
.terminal-diff-add { color: #6BCB95; }
.terminal-diff-del { color: #E48A8A; }
.terminal-success  { color: #6BCB95; }
.terminal-comment  { color: rgba(247, 245, 239, 0.45); }

/* ========================================
   Form Section
   ======================================== */

.form-section {
  background: var(--paper-sunk);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}

.form-wrapper {
  max-width: 520px;
  margin: 0 auto;
}

.form-card {
  background: var(--paper-raised);
  border: 1px solid var(--rule);
  border-radius: var(--radius-xl);
  padding: clamp(var(--space-xl), 5vw, var(--space-2xl));
}

.form-card .section-tag {
  margin-bottom: var(--space-sm);
}

.form-card .section-title {
  font-size: var(--fs-28);
  line-height: var(--lh-snug);
}

.form-card .section-subtitle {
  font-size: var(--fs-14);
  margin-top: var(--space-md);
}

[data-lead-form] {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  margin-top: var(--space-xl);
}

[data-lead-form] label {
  display: block;
  font-family: var(--font-sans);
  font-size: var(--fs-12);
  font-weight: 500;
  letter-spacing: var(--track-wide);
  text-transform: uppercase;
  color: var(--ink-soft);
  margin-bottom: var(--space-xs);
}

[data-lead-form] input[type="text"],
[data-lead-form] input[type="email"] {
  width: 100%;
  padding: 10px 0;
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--rule-strong);
  border-radius: 0;
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: var(--fs-18);
  outline: none;
  transition: border-bottom-color var(--duration-fast) var(--ease-snap),
              box-shadow         var(--duration-fast) var(--ease-snap);
}

[data-lead-form] input::placeholder {
  color: var(--ink-mute);
  opacity: 0.6;
}

[data-lead-form] input:focus {
  border-bottom-color: var(--ink);
  box-shadow: inset 0 -1px 0 0 var(--ink);
}

[data-lead-form] input[aria-invalid="true"] {
  border-bottom-color: var(--danger);
}

.honeypot {
  position: absolute;
  left: -9999px;
  opacity: 0;
  height: 0;
  width: 0;
  overflow: hidden;
}

.form-submit {
  width: 100%;
  padding: 16px 24px;
  background: var(--ink);
  color: var(--paper);
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-sans);
  font-size: var(--fs-16);
  font-weight: 600;
  letter-spacing: var(--track-flat);
  cursor: pointer;
  transition: background var(--duration-fast) var(--ease-snap),
              transform  var(--duration-fast) var(--ease-snap);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  margin-top: var(--space-sm);
  min-height: 48px;
}

.form-submit:hover {
  background: var(--rust-deep);
}

.form-submit:active {
  transform: translateY(1px);
}

.form-submit:focus-visible {
  outline: 2px solid var(--rust);
  outline-offset: 3px;
}

.form-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.form-note {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  color: var(--ink-mute);
  margin-top: var(--space-md);
  text-align: left;
  letter-spacing: var(--track-flat);
  line-height: var(--lh-normal);
}

.form-error {
  color: var(--danger);
  font-size: var(--fs-14);
  display: none;
  margin-top: var(--space-xs);
}

.form-success {
  display: none;
  text-align: left;
  padding: var(--space-xl) 0 0;
  border-top: 1px solid var(--rule);
  margin-top: var(--space-xl);
}

.form-success h3 {
  color: var(--success);
  margin-bottom: var(--space-sm);
  font-size: var(--fs-22);
  font-weight: 600;
}

.form-success p {
  color: var(--ink-soft);
  font-size: var(--fs-14);
}

/* ========================================
   Footer
   ======================================== */

.footer {
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--rule);
  background: var(--paper);
}

.footer p {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  letter-spacing: var(--track-flat);
  margin: 0;
  color: var(--ink-mute);
  line-height: var(--lh-loose);
}

.footer .footer-legal {
  color: var(--ink-soft);
  margin-bottom: var(--space-xs);
}

.footer .footer-meta {
  color: var(--ink-mute);
}

.footer a {
  color: var(--ink-soft);
  text-decoration: underline;
  text-decoration-color: var(--rule-strong);
  text-underline-offset: 2px;
  transition: text-decoration-color var(--duration-fast) var(--ease-snap),
              color                 var(--duration-fast) var(--ease-snap);
}

.footer a:hover {
  color: var(--rust);
  text-decoration-color: var(--rust);
}

/* ========================================
   Aulas Page
   ======================================== */

.aulas-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-2xl);
  padding-top: 6rem;
  min-height: 100vh;
}

.aulas-sidebar {
  position: sticky;
  top: 5rem;
  height: fit-content;
  max-height: calc(100vh - 6rem);
  overflow-y: auto;
  padding-right: var(--space-md);
  border-right: 1px solid var(--rule);
}

.aulas-sidebar h2 {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  text-transform: uppercase;
  letter-spacing: var(--track-wide);
  color: var(--ink-mute);
  margin-bottom: var(--space-md);
  font-weight: 500;
}

.sidebar-item {
  display: flex;
  align-items: baseline;
  gap: var(--space-md);
  padding: var(--space-md) var(--space-sm);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--duration-fast) var(--ease-snap);
  border-left: 3px solid transparent;
  margin-bottom: var(--space-xs);
}

.sidebar-item:hover {
  background: var(--paper-hover);
}

.sidebar-item.active {
  background: var(--paper-hover);
  border-left-color: var(--rust);
}

.sidebar-item .num {
  font-family: var(--font-mono);
  font-weight: 500;
  font-size: var(--fs-12);
  color: var(--ink-mute);
  flex-shrink: 0;
  width: 24px;
}

.sidebar-item.active .num {
  color: var(--rust);
}

.sidebar-item .name {
  font-size: var(--fs-14);
  color: var(--ink-soft);
  line-height: var(--lh-snug);
}

.sidebar-item.active .name {
  color: var(--ink);
  font-weight: 500;
}

.aulas-main {
  padding-bottom: var(--space-3xl);
}

.video-container {
  position: relative;
  width: 100%;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--ink);
  border: 1px solid var(--rule);
  aspect-ratio: 16 / 9;
  box-shadow: var(--shadow-md);
}

.video-container video,
.video-container iframe {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.video-info {
  margin-top: var(--space-xl);
  max-width: 70ch;
}

.video-info h1 {
  font-size: var(--fs-28);
  font-weight: 600;
  letter-spacing: var(--track-tight);
  margin-bottom: var(--space-sm);
  line-height: var(--lh-snug);
}

.video-info p {
  color: var(--ink-soft);
  line-height: var(--lh-loose);
  font-size: var(--fs-16);
}

/* ========================================
   Animations
   ======================================== */

.fade-in {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity var(--duration-slow) var(--ease-snap),
              transform var(--duration-slow) var(--ease-snap);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.stagger > .fade-in:nth-child(1) { transition-delay: 0ms; }
.stagger > .fade-in:nth-child(2) { transition-delay: 60ms; }
.stagger > .fade-in:nth-child(3) { transition-delay: 120ms; }
.stagger > .fade-in:nth-child(4) { transition-delay: 180ms; }
.stagger > .fade-in:nth-child(5) { transition-delay: 240ms; }
.stagger > .fade-in:nth-child(6) { transition-delay: 300ms; }

/* ========================================
   Responsive
   ======================================== */

@media (max-width: 1023px) {
  .hero h1 {
    max-width: 18ch;
  }
}

@media (max-width: 768px) {
  .hero {
    padding: 6rem 0 var(--space-3xl);
  }

  .section {
    padding: var(--space-3xl) 0;
  }

  .aulas-layout {
    grid-template-columns: 1fr;
    padding-top: 5rem;
    gap: var(--space-lg);
  }

  .aulas-sidebar {
    position: static;
    max-height: none;
    display: flex;
    overflow-x: auto;
    gap: var(--space-sm);
    padding-right: 0;
    padding-bottom: var(--space-md);
    border-right: none;
    border-bottom: 1px solid var(--rule);
    margin-bottom: var(--space-md);
  }

  .aulas-sidebar h2 {
    display: none;
  }

  .sidebar-item {
    flex-shrink: 0;
    margin-bottom: 0;
  }

  .form-card {
    padding: var(--space-xl) var(--space-lg);
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 var(--space-md);
  }

  .nav-cta span {
    display: none;
  }
}