/* Direction: Professional tech/SaaS masterclass — light background, vibrant purple-indigo accent, clean sans-serif */
:root {
  --color-bg: #f5f5f8;
  --color-surface: #ffffff;
  --color-surface-elevated: #ececf4;
  --color-border: #dfdff0;
  --color-text-primary: #1a1a2e;
  --color-text-secondary: #555570;
  --color-text-muted: #8888a0;
  --color-primary: #7c3aed;
  --color-primary-hover: #6d28d9;
  --color-accent: #3b82f6;
  --color-accent-glow: rgba(124, 58, 237, 0.2);
  --color-success: #16a34a;
  --color-warning: #d97706;
  --color-danger: #dc2626;
  --font-heading: 'Inter', system-ui, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --shadow-soft: 0 4px 24px rgba(0, 0, 0, 0.08);
  --shadow-glow: 0 0 40px rgba(124, 58, 237, 0.1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-body);
  background: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.65;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

a { color: var(--color-accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Section rhythm */
section { padding: 100px 24px; }
@media (min-width: 768px) { section { padding: 110px 40px; } }
@media (min-width: 1280px) { section { padding: 120px 60px; } }

.container { max-width: 1100px; margin: 0 auto; }

/* Countdown */
.countdown { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.countdown-item {
  background: var(--color-surface-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 16px 20px;
  min-width: 80px;
  text-align: center;
}
.countdown-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--color-primary);
  line-height: 1;
}
.countdown-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-muted);
  margin-top: 4px;
}

/* Buttons */
.btn-primary {
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--color-primary); color: #fff;
  padding: 14px 32px; border-radius: var(--radius-md);
  font-weight: 600; font-size: 1rem;
  border: none; cursor: pointer;
  min-height: 48px; transition: background 150ms ease, box-shadow 150ms ease;
}
.btn-primary:hover { background: var(--color-primary-hover); box-shadow: var(--shadow-glow); }
.btn-primary:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
.btn-primary:active { transform: scale(0.98); }

.btn-secondary {
  display: inline-flex; align-items: center; justify-content: center;
  background: transparent; color: var(--color-text-primary);
  padding: 14px 32px; border-radius: var(--radius-md);
  font-weight: 600; font-size: 1rem;
  border: 1px solid var(--color-border); cursor: pointer;
  min-height: 48px; transition: border-color 150ms ease, background 150ms ease;
}
.btn-secondary:hover { border-color: var(--color-primary); background: var(--color-surface-elevated); }
.btn-secondary:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }

/* Cards */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: border-color 150ms ease, box-shadow 150ms ease;
}
.card:hover { border-color: var(--color-primary); box-shadow: var(--shadow-glow); }

/* Learning grid */
.learn-grid {
  display: grid; gap: 24px;
  grid-template-columns: 1fr;
}
@media (min-width: 768px) { .learn-grid { grid-template-columns: repeat(2, 1fr); } }
.learn-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 28px;
  transition: border-color 150ms ease, transform 150ms ease;
}
.learn-item:hover { border-color: var(--color-primary); transform: translateY(-2px); }
.learn-icon {
  width: 44px; height: 44px; border-radius: var(--radius-sm);
  background: var(--color-accent-glow); display: flex; align-items: center; justify-content: center;
  color: var(--color-accent); margin-bottom: 16px; font-size: 1.2rem;
}

/* Agenda timeline */
.timeline { position: relative; padding-left: 32px; }
.timeline::before {
  content: ''; position: absolute; left: 11px; top: 0; bottom: 0;
  width: 2px; background: var(--color-border);
}
.timeline-item { position: relative; padding-bottom: 32px; }
.timeline-item::before {
  content: ''; position: absolute; left: -32px; top: 4px;
  width: 14px; height: 14px; border-radius: 50%;
  background: var(--color-primary); border: 3px solid var(--color-bg);
}
.timeline-item:last-child { padding-bottom: 0; }
.timeline-time {
  font-weight: 700; color: var(--color-accent);
  font-size: 0.9rem; letter-spacing: 0.02em;
}

/* FAQ accordion */
.faq-item { border-bottom: 1px solid var(--color-border); }
.faq-question {
  width: 100%; text-align: left; background: none; border: none;
  cursor: pointer; padding: 24px 0; display: flex; align-items: center;
  justify-content: space-between; font-size: 1.05rem; font-weight: 600;
  color: var(--color-text-primary); font-family: var(--font-body);
  transition: color 150ms ease;
}
.faq-question:hover { color: var(--color-accent); }
.faq-question:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
.faq-chevron { transition: transform 300ms ease; color: var(--color-text-muted); font-size: 1.2rem; }
.faq-item.open .faq-chevron { transform: rotate(180deg); }
.faq-item.open .faq-question { color: var(--color-accent); }
.faq-answer {
  max-height: 0; overflow: hidden; transition: max-height 300ms ease, padding 300ms ease;
  color: var(--color-text-secondary); line-height: 1.7;
}
.faq-item.open .faq-answer { max-height: 500px; padding-bottom: 24px; }

/* Form */
.form-group { margin-bottom: 20px; }
.form-label { display: block; font-size: 0.875rem; font-weight: 600; margin-bottom: 6px; color: var(--color-text-secondary); }
.form-input {
  width: 100%; padding: 12px 16px; background: var(--color-surface-elevated);
  border: 1px solid var(--color-border); border-radius: var(--radius-sm);
  color: var(--color-text-primary); font-size: 1rem; font-family: var(--font-body);
  transition: border-color 150ms ease; min-height: 48px;
}
.form-input:focus { outline: none; border-color: var(--color-primary); box-shadow: 0 0 0 3px var(--color-accent-glow); }
.form-input.error { border-color: var(--color-danger); }
.form-error { color: var(--color-danger); font-size: 0.8rem; margin-top: 4px; display: none; }
.form-error.show { display: block; }
.form-success {
  background: rgba(34, 197, 94, 0.1); border: 1px solid var(--color-success);
  border-radius: var(--radius-md); padding: 24px; text-align: center; color: var(--color-success);
}

/* Nav */
.nav { position: sticky; top: 0; z-index: 50; background: rgba(245, 245, 248, 0.85); backdrop-filter: blur(12px); border-bottom: 1px solid var(--color-border); }
.nav-inner { max-width: 1100px; margin: 0 auto; padding: 16px 24px; display: flex; align-items: center; justify-content: space-between; }
.nav-logo { font-family: var(--font-heading); font-weight: 800; font-size: 1.25rem; color: var(--color-text-primary); }
.nav-logo span { color: var(--color-primary); }
.nav-links { display: none; gap: 32px; list-style: none; }
@media (min-width: 768px) { .nav-links { display: flex; } }
.nav-links a { color: var(--color-text-secondary); font-size: 0.9rem; font-weight: 500; transition: color 150ms ease; }
.nav-links a:hover { color: var(--color-text-primary); text-decoration: none; }
.nav-links a.active { color: var(--color-primary); }

/* Hero glow */
.hero-glow {
  position: absolute; width: 600px; height: 600px; border-radius: 50%;
  background: radial-gradient(circle, rgba(124, 58, 237, 0.06) 0%, transparent 70%);
  top: 50%; left: 50%; transform: translate(-50%, -50%); pointer-events: none;
}

/* Badge */
.badge {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--color-surface-elevated); border: 1px solid var(--color-border);
  border-radius: 100px; padding: 8px 16px; font-size: 0.8rem;
  color: var(--color-text-secondary); font-weight: 500;
}

/* Section heading */
.section-heading { text-align: center; margin-bottom: 64px; }
.section-heading h2 { font-size: 2rem; margin-bottom: 16px; }
@media (min-width: 768px) { .section-heading h2 { font-size: 2.5rem; } }
.section-heading p { color: var(--color-text-secondary); max-width: 600px; margin: 0 auto; font-size: 1.05rem; }

/* Speaker */
.speaker-card { display: flex; flex-direction: column; align-items: center; text-align: center; }
.speaker-avatar {
  width: 96px; height: 96px; border-radius: 50%; object-fit: cover;
  border: 3px solid var(--color-primary); margin-bottom: 20px;
}
.speaker-name { font-size: 1.25rem; margin-bottom: 4px; }
.speaker-role { color: var(--color-accent); font-size: 0.9rem; font-weight: 500; }

/* Responsive tweaks */
@media (max-width: 767px) {
  .countdown-item { min-width: 64px; padding: 12px 14px; }
  .countdown-number { font-size: 1.8rem; }
}

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