/* ============================================================
   SKY LIGHT — Design System
   Light, airy, cloud-like aesthetic with sky blue accents
   ============================================================ */

/* --- Tailwind CDN loaded via <script> in PHP --- */

/* --- Custom Properties --- */
:root {
  --sky-50:  #f0f9ff;
  --sky-100: #e0f2fe;
  --sky-200: #bae6fd;
  --sky-300: #7dd3fc;
  --sky-400: #38bdf8;
  --sky-500: #0ea5e9;
  --sky-600: #0284c7;
  --sky-700: #0369a1;
  --sky-800: #075985;
  --sky-900: #0c4a6e;
  --white:   #ffffff;
  --gray-50: #f9fafb;
  --gray-100:#f3f4f6;
  --gray-200:#e5e7eb;
  --gray-600:#4b5563;
  --gray-700:#374151;
  --gray-800:#1f2937;
  --gray-900:#111827;
}

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

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

body {
  font-family: 'Inter', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  background-color: var(--white);
  color: var(--gray-800);
  line-height: 1.7;
  overflow-x: hidden;
}

/* --- Sky Gradient Accents --- */
.sky-gradient-top {
  background: linear-gradient(180deg, var(--sky-50) 0%, var(--white) 100%);
}

.sky-gradient-section {
  background: linear-gradient(180deg, var(--sky-50) 0%, var(--white) 40%, var(--white) 100%);
}

.sky-gradient-accent {
  background: linear-gradient(135deg, var(--sky-400), var(--sky-500));
}

.sky-gradient-soft {
  background: linear-gradient(135deg, var(--sky-100), var(--sky-50), var(--white));
}

/* --- Cloud-like decorative elements --- */
.cloud-divider {
  position: relative;
}

.cloud-divider::before {
  content: '';
  position: absolute;
  top: -40px;
  left: 50%;
  transform: translateX(-50%);
  width: 200px;
  height: 40px;
  background: radial-gradient(ellipse at center, var(--sky-200) 0%, transparent 70%);
  border-radius: 50%;
  opacity: 0.6;
}

/* --- Cards with Sky Shadow --- */
.card-sky {
  background: var(--white);
  border-radius: 1rem;
  box-shadow:
    0 4px 6px -1px rgba(14, 165, 233, 0.08),
    0 2px 4px -2px rgba(14, 165, 233, 0.05),
    0 0 0 1px rgba(14, 165, 233, 0.04);
  transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.card-sky:hover {
  transform: translateY(-6px);
  box-shadow:
    0 12px 24px -6px rgba(14, 165, 233, 0.15),
    0 4px 8px -4px rgba(14, 165, 233, 0.08),
    0 0 0 1px rgba(14, 165, 233, 0.08);
}

/* --- Feature Icon Wrapper --- */
.icon-sky-circle {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--sky-100), var(--sky-200));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--sky-500);
  font-size: 1.4rem;
  transition: all 0.3s ease;
  flex-shrink: 0;
}

.card-sky:hover .icon-sky-circle {
  background: linear-gradient(135deg, var(--sky-400), var(--sky-500));
  color: var(--white);
  transform: scale(1.08);
}

/* --- Stats Counter --- */
.stat-number {
  font-size: 2.8rem;
  font-weight: 800;
  background: linear-gradient(135deg, var(--sky-400), var(--sky-600));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* --- Navbar --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.82);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(14, 165, 233, 0.08);
  transition: all 0.3s ease;
}

.navbar.scrolled {
  box-shadow: 0 1px 3px rgba(14, 165, 233, 0.08);
  background: rgba(255, 255, 255, 0.94);
}

.nav-link {
  color: var(--gray-700);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem 1rem;
  border-radius: 0.5rem;
  transition: all 0.25s ease;
  text-decoration: none;
}

.nav-link:hover,
.nav-link.active {
  color: var(--sky-500);
  background: var(--sky-50);
}

/* --- Hero Section --- */
.hero-section {
  padding-top: 7rem;
  padding-bottom: 5rem;
  position: relative;
  overflow: hidden;
}

.hero-bg-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.15;
  pointer-events: none;
}

.hero-orb-1 {
  width: 400px;
  height: 400px;
  background: var(--sky-300);
  top: -100px;
  right: -80px;
}

.hero-orb-2 {
  width: 300px;
  height: 300px;
  background: var(--sky-200);
  bottom: -60px;
  left: -60px;
}

/* --- CTA Buttons --- */
.btn-sky {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 2rem;
  border-radius: 9999px;
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: all 0.3s ease;
  cursor: pointer;
  border: none;
}

.btn-sky-primary {
  background: linear-gradient(135deg, var(--sky-400), var(--sky-500));
  color: var(--white);
  box-shadow: 0 4px 14px rgba(14, 165, 233, 0.28);
}

.btn-sky-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(14, 165, 233, 0.36);
}

.btn-sky-outline {
  background: var(--white);
  color: var(--sky-500);
  border: 2px solid var(--sky-300);
}

.btn-sky-outline:hover {
  background: var(--sky-50);
  border-color: var(--sky-400);
  transform: translateY(-2px);
}

/* --- Section Titles --- */
.section-label {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--sky-500);
  background: var(--sky-50);
  padding: 0.3rem 1rem;
  border-radius: 9999px;
  margin-bottom: 0.75rem;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 1rem;
  line-height: 1.3;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--gray-600);
  max-width: 600px;
  margin: 0 auto;
}

/* --- FAQ Accordion --- */
.faq-item {
  border-bottom: 1px solid var(--sky-100);
  overflow: hidden;
}

.faq-question {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 1.25rem 0;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--gray-800);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  transition: color 0.25s ease;
}

.faq-question:hover {
  color: var(--sky-500);
}

.faq-icon {
  font-size: 1.1rem;
  color: var(--sky-400);
  transition: transform 0.35s ease;
  flex-shrink: 0;
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s ease, padding-bottom 0.4s ease;
}

.faq-item.active .faq-answer {
  max-height: 300px;
  padding-bottom: 1.25rem;
}

.faq-answer p {
  color: var(--gray-600);
  line-height: 1.8;
  margin: 0;
}

/* --- Testimonial Card --- */
.testimonial-card {
  background: var(--white);
  border-radius: 1rem;
  padding: 2rem;
  position: relative;
  box-shadow:
    0 4px 6px -1px rgba(14, 165, 233, 0.06),
    0 2px 4px -2px rgba(14, 165, 233, 0.04);
  transition: all 0.35s ease;
}

.testimonial-card:hover {
  transform: translateY(-4px);
  box-shadow:
    0 12px 24px -6px rgba(14, 165, 233, 0.12),
    0 4px 8px -4px rgba(14, 165, 233, 0.06);
}

.testimonial-card::before {
  content: '\201C';
  font-size: 4rem;
  line-height: 1;
  color: var(--sky-200);
  position: absolute;
  top: 1rem;
  left: 1.5rem;
  font-family: serif;
}

/* --- Footer --- */
.footer {
  background: var(--gray-50);
  border-top: 1px solid var(--sky-100);
  padding: 3rem 0 2rem;
}

.footer a {
  color: var(--gray-600);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer a:hover {
  color: var(--sky-500);
}

/* --- Stats Section --- */
.stats-section {
  background: linear-gradient(135deg, var(--sky-50) 0%, var(--white) 50%, var(--sky-50) 100%);
}

/* --- Mobile Menu --- */
.mobile-menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--gray-700);
  cursor: pointer;
  padding: 0.25rem;
}

@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: block;
  }

  .nav-links {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.97);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--sky-100);
    padding: 1rem;
    gap: 0.5rem;
  }

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

  .section-title {
    font-size: 1.7rem;
  }

  .stat-number {
    font-size: 2.2rem;
  }
}

/* --- Breadcrumb --- */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--gray-600);
  padding: 0.5rem 0;
}

.breadcrumb a {
  color: var(--sky-500);
  text-decoration: none;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

.breadcrumb span {
  color: var(--gray-400);
}

/* --- Contact Form --- */
.form-input {
  width: 100%;
  padding: 0.85rem 1.1rem;
  border: 1.5px solid var(--sky-200);
  border-radius: 0.75rem;
  font-size: 0.95rem;
  color: var(--gray-800);
  background: var(--white);
  transition: all 0.25s ease;
  outline: none;
  font-family: inherit;
}

.form-input:focus {
  border-color: var(--sky-400);
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.1);
}

.form-input::placeholder {
  color: var(--gray-400);
}

textarea.form-input {
  resize: vertical;
  min-height: 140px;
}

/* --- Animations --- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes floatCloud {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.animate-fade-in-up {
  animation: fadeInUp 0.7s ease forwards;
}

.animate-delay-100 { animation-delay: 0.1s; }
.animate-delay-200 { animation-delay: 0.2s; }
.animate-delay-300 { animation-delay: 0.3s; }
.animate-delay-400 { animation-delay: 0.4s; }
.animate-delay-500 { animation-delay: 0.5s; }

/* --- Scroll Reveal --- */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* --- Decorative Clouds --- */
.cloud-float {
  animation: floatCloud 5s ease-in-out infinite;
}

.cloud-float-slow {
  animation: floatCloud 7s ease-in-out infinite;
}

/* --- Badge --- */
.badge-sky {
  display: inline-block;
  background: linear-gradient(135deg, var(--sky-400), var(--sky-500));
  color: var(--white);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.2rem 0.7rem;
  border-radius: 9999px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* --- Page Header (for inner pages) --- */
.page-header {
  padding-top: 6rem;
  padding-bottom: 3rem;
  background: linear-gradient(180deg, var(--sky-50) 0%, var(--white) 100%);
  text-align: center;
}

.page-header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 0.5rem;
}