:root {
  --bg-color: #f9fafb;
  --card-bg: #ffffff;
  --border-color: #d9e0e6;
  --text-color: #1a1f26;
  --subtle-text: #5a6470;

  --primary-color: #2b6cb0;
  --primary-hover: #265a91;
  --gradient-start: #2b6cb0;
  --gradient-end: #63b3ed;
  --success-color: #38a169;

  --header-h: 70px;
}

[data-theme="dark"] {
  --bg-color: #1a202c;
  --text-color: #e2e8f0;
  --card-bg: #2d3748;
  --border-color: #4a5568;
  --primary-color: #63b3ed;
  --primary-hover: #90cdf4;
  --subtle-text: #a0aec0;
  --gradient-start: #63b3ed;
  --gradient-end: #4299e1;
  --success-color: #68d391;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}
body {
  font-family: "Inter", sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  transition: background-color 0.3s, color 0.3s;
}

body.menu-open {
  overflow: hidden;
  touch-action: none;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}
section {
  padding: 80px 0;
}
.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 800;
  text-align: center;
  margin-bottom: 10px;
}
.section-subtitle {
  text-align: center;
  font-size: clamp(1rem, 2.5vw, 1.1rem);
  color: var(--subtle-text);
  margin-bottom: 60px;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}
.btn {
  display: inline-block;
  padding: 12px 28px;
  background-image: linear-gradient(
    to right,
    var(--gradient-start) 0%,
    var(--gradient-end) 100%
  );
  color: white;
  border: none;
  border-radius: 999px;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  transition: transform 0.2s, box-shadow 0.2s;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  -webkit-tap-highlight-color: transparent;
}
.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.15);
}

header {
  position: fixed;
  inset: 0 0 auto 0;
  height: var(--header-h);
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
  padding-top: env(safe-area-inset-top);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
  box-shadow: 0 1px 8px rgba(0, 0, 0, 0.04);
}

[data-theme="dark"] header {
  background-color: rgba(26, 32, 44, 0.9);
}
nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: var(--header-h);
  gap: 12px;
}
.logo {
  font-size: 1.1rem;
  font-weight: 800;
  text-decoration: none;
  color: var(--primary-color);
  white-space: nowrap;
  transition: color 0.2s;
}
.logo:hover {
  color: var(--primary-hover);
}
.nav-group {
  display: flex;
  align-items: center;
  gap: 25px;
}
.nav-links {
  display: flex;
  list-style: none;
  gap: 20px;
}
.nav-links a {
  text-decoration: none;
  color: var(--subtle-text);
  font-weight: 500;
  font-size: 1.05rem;
  transition: color 0.2s;
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--primary-color);
}
.theme-switcher {
  cursor: pointer;
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--subtle-text);
  line-height: 1;
  padding: 0;
  transition: transform 0.2s;
}
.theme-switcher:hover {
  transform: scale(1.1);
}

.hamburger {
  display: none;
}

@media (max-width: 768px) {
  .nav-group {
    display: none;
  }

  .hamburger {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 40px;
    width: 44px;
    cursor: pointer;
    font-size: 1.6rem;
    color: var(--text-color);
    background: none;
    border: 1px solid transparent;
    border-radius: 8px;
    z-index: 1201;
  }

  .mobile-panel {
    position: fixed;
    top: var(--header-h);
    left: 0;
    right: 0;
    z-index: 1200;
    background: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    transform: translateY(-10px);
    opacity: 0;
    visibility: hidden;
    transition: transform 0.18s ease, opacity 0.18s ease, visibility 0.18s ease;
    padding: 12px 16px 100px;
    text-align: center;
  }

  .mobile-panel.open {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .mobile-nav {
    display: flex; /* <-- CHANGED */
    flex-direction: column; /* <-- ADDED */
    align-items: center; /* <-- CHANGED */
    gap: 8px; /* <-- CHANGED (row-gap -> gap) */
    max-width: 1100px;
    margin: 0 auto;
  }

  .mobile-link {
    padding: 12px 6px;
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    font-size: 1.2rem;
  }

  .mobile-link:active,
  .mobile-link:focus,
  .mobile-link:hover {
    color: var(--primary-color);
  }

  .mobile-theme {
    margin-top: 6px;
    background: none;
    border: none;
    font-size: 1.4rem;
    cursor: pointer;
    color: var(--subtle-text);
  }
}

#hero {
  padding-top: calc(var(--header-h) + 60px);
  min-height: 100svh;
  display: flex;
  align-items: center;
  text-align: center;
}
.hero-content {
  max-width: 800px;
  margin: 0 auto;
  padding-top: env(safe-area-inset-top);
}
.hero-content h1 {
  font-size: clamp(2rem, 6vw, 3.5rem);
  font-weight: 800;
  margin-bottom: 16px;
  line-height: 1.2;
}
.hero-content p {
  font-size: clamp(1rem, 3.5vw, 1.2rem);
  color: var(--subtle-text);
  margin-bottom: 28px;
  max-width: 650px;
  margin-left: auto;
  margin-right: auto;
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}
.service-card {
  background: var(--card-bg);
  padding: clamp(22px, 4vw, 40px);
  border-radius: 12px;
  border: 1px solid var(--border-color);
  text-align: center;
  transition: transform 0.3s, box-shadow 0.3s;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.03);
}
.service-card:hover {
  transform: translateY(-6px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
}
.service-icon {
  height: 46px;
  width: 46px;
  margin-bottom: 16px;
  color: var(--primary-color);
}
.service-card h3 {
  font-size: 1.25rem;
  margin-bottom: 10px;
}
.service-card p {
  color: var(--subtle-text);
  font-size: 0.98rem;
}

.case-study {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  align-items: center;
  gap: 40px;
  margin-bottom: 64px;
}
.case-study:last-child {
  margin-bottom: 0;
}
.case-study:nth-child(even) .case-study-company {
  order: 2;
}
.case-study-company {
  background-color: var(--card-bg);
  border-radius: 12px;
  padding: 32px;
  border: 1px solid var(--border-color);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--subtle-text);
  text-align: center;
}
.case-study-content h4 {
  color: var(--primary-color);
  font-weight: 700;
  margin-bottom: 8px;
  font-size: 0.95rem;
  letter-spacing: 0.02em;
}
.case-study-content h3 {
  font-size: clamp(1.25rem, 4.5vw, 2rem);
  margin-bottom: 14px;
}
.case-study-content p {
  color: var(--subtle-text);
  margin-bottom: 18px;
  font-size: 0.98rem;
}
.result-item h5 {
  font-size: clamp(1.5rem, 6vw, 2.2rem);
  font-weight: 800;
  color: var(--primary-color);
}
.result-item p {
  font-size: 0.9rem;
  color: var(--subtle-text);
  margin-bottom: 0;
}

.testimonial-card {
  background: var(--card-bg);
  padding: 24px;
  border-left: 4px solid var(--primary-color);
  margin-bottom: 18px;
}
.testimonial-text {
  font-style: italic;
  color: var(--subtle-text);
  margin-bottom: 16px;
}

#cta {
  background-color: var(--card-bg);
  text-align: center;
}

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s, visibility 0.3s;
  padding: env(safe-area-inset-top) env(safe-area-inset-right)
    env(safe-area-inset-bottom) env(safe-area-inset-left);
}
.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}
.modal-content {
  background: var(--bg-color);
  padding: clamp(20px, 4.5vw, 40px);
  border-radius: 12px;
  width: min(92%, 500px);
  position: relative;
  transform: translateY(20px);
  transition: transform 0.3s;
}
.modal-overlay.active .modal-content {
  transform: translateY(0);
}
.modal-close {
  position: absolute;
  top: 12px;
  right: 12px;
  font-size: 1.5rem;
  color: var(--subtle-text);
  background: none;
  border: none;
  cursor: pointer;
}
#contact-form h3 {
  text-align: center;
  margin-bottom: 16px;
  font-size: 1.4rem;
}
.form-group {
  margin-bottom: 16px;
}
.form-group label {
  display: block;
  margin-bottom: 6px;
  font-weight: 500;
  color: var(--subtle-text);
  font-size: 0.95rem;
}
.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background: var(--card-bg);
  color: var(--text-color);
  font-family: "Inter", sans-serif;
}
#form-result {
  margin-top: 14px;
  text-align: center;
  font-weight: 500;
}
.success-message {
  color: var(--success-color);
  font-size: 1.05rem;
}

/* FOOTER */
footer {
  padding: 30px 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
}
footer p {
  color: var(--subtle-text);
  font-size: 0.9rem;
}

@media (max-width: 900px) {
  .case-study {
    grid-template-columns: 1fr;
    gap: 22px;
  }
  .case-study:nth-child(even) .case-study-company {
    order: 0;
  }
  .case-study-company {
    margin-bottom: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  * {
    animation: none !important;
    transition: none !important;
    scroll-behavior: auto !important;
  }
}