:root {
  --color-primary: #1a2a6c;
  --color-primary-dark: #0f1b4a;
  --color-accent: #b91c6c;
  --color-accent-light: #e64980;
  --color-bg: #f5f0fd;
  --color-surface: #ffffff;
  --color-text: #1a1a2e;
  --color-text-light: #5a5a7a;
  --color-border: #d4c7f0;
  --font-family: system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

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

.container {
  max-width: 1024px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* Header */
header {
  background: var(--color-primary);
  color: #fff;
  padding: 1rem 0;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
}

.logo {
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}

nav a {
  color: #e0dbff;
  text-decoration: none;
  margin-left: 1.5rem;
  font-size: 0.95rem;
  transition: color 0.2s;
}

nav a:hover {
  color: #fff;
  text-decoration: underline;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 60%, var(--color-accent) 100%);
  color: #fff;
  text-align: center;
  padding: 5rem 0 4rem;
}

.hero h1 {
  font-size: 3rem;
  margin-bottom: 0.5rem;
  letter-spacing: -1px;
}

.subtitle {
  font-size: 1.25rem;
  max-width: 600px;
  margin: 0 auto 1rem;
  opacity: 0.9;
}

.date-location {
  font-size: 1rem;
  margin-bottom: 2rem;
  opacity: 0.8;
}

.btn {
  display: inline-block;
  padding: 0.8rem 2rem;
  background: var(--color-accent);
  color: #fff;
  text-decoration: none;
  border-radius: 8px;
  font-weight: 600;
  transition: background 0.2s;
  border: none;
  cursor: pointer;
}

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

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

/* Sections */
.section {
  padding: 3.5rem 0;
}

.section:nth-child(even) {
  background: var(--color-surface);
}

.section h2 {
  font-size: 2rem;
  margin-bottom: 1.5rem;
  color: var(--color-primary-dark);
}

.section p {
  margin-bottom: 1rem;
  color: var(--color-text-light);
  max-width: 720px;
}

/* Schedule */
.schedule {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.schedule-item {
  display: flex;
  align-items: flex-start;
  gap: 1.5rem;
  padding: 1rem;
  background: var(--color-bg);
  border-radius: 8px;
  border-left: 4px solid var(--color-accent);
}

.time {
  font-weight: 700;
  color: var(--color-accent);
  min-width: 4rem;
  font-size: 1.1rem;
}

.schedule-item h3 {
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
  color: var(--color-text);
}

.schedule-item p {
  font-size: 0.95rem;
  margin: 0;
  color: var(--color-text-light);
}

/* Speakers */
.speakers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 2rem;
  margin-top: 1.5rem;
}

.speaker {
  text-align: center;
  padding: 1.5rem 1rem;
  background: var(--color-surface);
  border-radius: 12px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
  transition: box-shadow 0.2s;
}

.speaker:hover {
  box-shadow: 0 4px 20px rgba(0,0,0,0.1);
}

.speaker-photo {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background-size: cover;
  background-position: center;
  margin: 0 auto 1rem;
  border: 3px solid var(--color-accent-light);
}

.speaker h3 {
  font-size: 1.1rem;
  margin-bottom: 0.25rem;
  color: var(--color-primary-dark);
}

.speaker .role {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-accent);
  margin-bottom: 0.5rem;
}

.speaker .bio {
  font-size: 0.9rem;
  color: var(--color-text-light);
  line-height: 1.4;
}

/* Form */
#registration-form {
  max-width: 500px;
  margin: 1.5rem auto 0;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

#registration-form label {
  font-weight: 600;
  font-size: 0.95rem;
}

#registration-form input,
#registration-form select {
  padding: 0.6rem 0.8rem;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 1rem;
  font-family: inherit;
  background: var(--color-surface);
  transition: border-color 0.2s;
}

#registration-form input:focus,
#registration-form select:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 2px rgba(185,28,108,0.15);
}

#registration-form button {
  align-self: flex-start;
  margin-top: 0.5rem;
}

.form-feedback {
  margin-top: 1rem;
  font-weight: 600;
  color: var(--color-accent);
  text-align: center;
}

/* Contact */
.contact-email,
.contact-phone {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--color-primary-dark);
}

.contact-email {
  margin-bottom: 0.25rem;
}

/* Footer */
footer {
  background: var(--color-primary-dark);
  color: #c4c0e0;
  text-align: center;
  padding: 2rem 0;
  font-size: 0.9rem;
}

footer p {
  margin-bottom: 0.5rem;
}

/* Responsive */
@media (max-width: 640px) {
  .header-content {
    flex-direction: column;
    gap: 0.5rem;
  }

  nav a {
    margin: 0 0.75rem;
    font-size: 0.85rem;
  }

  .hero {
    padding: 3rem 0 2.5rem;
  }

  .hero h1 {
    font-size: 2.2rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .schedule-item {
    flex-direction: column;
    gap: 0.5rem;
  }

  .time {
    min-width: auto;
  }

  .speakers-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 480px) {
  .speakers-grid {
    grid-template-columns: 1fr;
  }
}