/* css variables - includes extra error colours for form validation */
:root {
  --primary:    #5B21B6;
  --accent:     #8B5CF6;
  --bg:         #F9F9F9;
  --card-bg:    #FFFFFF;
  --text-dark:  #1A1A1A;
  --text-muted: #6B7280;
  --border:     #E5E7EB;
  --error:      #C62828;
  --error-bg:   #FFEBEE;
}

/* reset default browser margin and padding */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* base body styles */
body {
  font-family: 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text-dark);
  line-height: 1.6;
}

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

/* narrower max width for the form layout */
.container {
  max-width: 700px;
  margin: 0 auto;
  padding: 0 24px 60px;
}

/* navbar - sticks to top while scrolling */
.navbar {
  position: sticky;
  top: 0; z-index: 100;
  background: var(--card-bg);
  border-bottom: 1px solid var(--border);
  height: 64px;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo { font-size: 1.3rem; font-weight: 700; color: var(--primary); }

.nav-links { list-style: none; display: flex; gap: 32px; }

.nav-links a {
  color: var(--text-dark);
  font-size: 0.95rem;
  position: relative;
  transition: color 0.3s ease;
}

/* animated underline that grows on hover */
.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -3px; left: 0;
  width: 0; height: 2px;
  background: var(--primary);
  transition: width 0.3s ease;
}

.nav-links a:hover,
.nav-links a.active { color: var(--primary); font-weight: 600; }
.nav-links a:hover::after { width: 100%; }

/* hidden on desktop, shown on mobile */
.hamburger {
  display: none;
  background: none;
  border: none;
  font-size: 1.6rem;
  cursor: pointer;
  color: var(--text-dark);
}

/* purple gradient banner at the top of the page */
.page-header {
  background: linear-gradient(135deg, #3b0862, #7C3AED);
  color: #fff;
  text-align: center;
  padding: 60px 24px;
  margin-bottom: 40px;
}

.page-header h1 { font-size: 2.5rem; margin-bottom: 12px; }

.page-header p {
  font-size: 1.1rem;
  color: rgba(255,255,255,0.85);
}

/* white card wrapping the entire booking form */
.form-card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 40px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.08);
  border: 1px solid var(--border);
}

/* each logical section of the form, separated by a bottom border */
.form-section {
  margin-bottom: 36px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--border);
}

.form-section:last-of-type { border-bottom: none; }

/* section heading with a left purple accent bar */
.form-section-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 20px;
  padding-left: 10px;
  border-left: 4px solid var(--accent);
}

/* muted (optional) label next to section title */
.optional {
  font-weight: 400;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 6px;
}

/* red asterisk on required fields */
.required { color: var(--error); margin-left: 2px; }

/* shared styles for all input types */
.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="tel"],
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  font-size: 0.95rem;
  font-family: inherit;
  color: var(--text-dark);
  background: #fff;
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
  outline: none;
}

/* purple glow when a field is focused */
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(139,92,246,0.2);
}

/* red border and background when js marks a field invalid */
.form-group input.invalid,
.form-group select.invalid,
.form-group textarea.invalid {
  border-color: var(--error);
  background: var(--error-bg);
}

/* red error text shown below invalid fields */
.error-msg {
  display: block;
  color: var(--error);
  font-size: 0.8rem;
  margin-top: 4px;
  min-height: 18px;
}

/* row of day checkboxes */
.checkbox-row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 4px;
}

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  cursor: pointer;
  user-select: none;
}

/* checkbox styled with the primary purple colour */
.checkbox-label input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--primary);
  cursor: pointer;
}

.repeat-label {
  margin-top: 8px;
  font-size: 0.9rem;
}

/* light purple summary box that updates live as the user fills the form */
.summary-box {
  background: #EDE9FE;
  border: 1.5px solid var(--accent);
  border-radius: 12px;
  padding: 24px;
  margin-bottom: 28px;
}

.summary-box h3 {
  font-size: 1rem;
  color: var(--primary);
  margin-bottom: 14px;
}

.summary-row {
  display: flex;
  gap: 12px;
  margin-bottom: 8px;
  font-size: 0.9rem;
}

.summary-label {
  font-weight: 600;
  color: var(--text-dark);
  min-width: 90px;
}

.summary-val {
  color: var(--text-muted);
}

/* full width submit button */
.btn-submit {
  width: 100%;
  padding: 14px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-submit:hover {
  background: #3B0764;
  transform: translateY(-2px);
}

/* success card shown after booking, hidden by default */
.success-card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 60px 40px;
  text-align: center;
  box-shadow: 0 2px 12px rgba(0,0,0,0.08);
}

/* purple circle containing the tick icon */
.checkmark-circle {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
}

.checkmark-tick {
  color: #fff;
  font-size: 2rem;
  font-weight: 700;
  line-height: 1;
}

.success-card h2 {
  font-size: 1.8rem;
  color: var(--primary);
  margin-bottom: 14px;
}

.success-card p {
  color: var(--text-muted);
  margin-bottom: 28px;
  font-size: 0.95rem;
  line-height: 1.8;
}

/* button styles */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

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

.btn-primary:hover {
  background: #3B0764;
  transform: translateY(-2px);
}

/* footer */
.footer {
  background: var(--primary);
  color: #fff;
  text-align: center;
  padding: 24px;
  font-size: 0.9rem;
  margin-top: 60px;
}

/* mobile styles - breakpoint at 768px */
@media (max-width: 768px) {
  .hamburger { display: block; }

  .nav-links {
    display: none;
    position: absolute;
    top: 64px; left: 0; right: 0;
    background: var(--card-bg);
    flex-direction: column;
    gap: 0;
    border-bottom: 1px solid var(--border);
    box-shadow: 0 4px 12px rgba(0,0,0,0.08);
  }

  .nav-links.nav-open { display: flex; }

  .nav-links li a {
    display: block;
    padding: 14px 24px;
    border-bottom: 1px solid var(--border);
  }

  .form-card { padding: 24px; }

  .checkbox-row { gap: 10px; }

  .page-header h1 { font-size: 1.8rem; }
}