/* ==========================================================================
   Robinsight — Design System & Styles
   Clean, modern, lightweight. No frameworks.
   ========================================================================== */

/* --- CSS Custom Properties (Design Tokens) --- */
:root {
  /* Colors */
  --color-navy:       #0f1b2d;
  --color-navy-light: #1a2940;
  --color-teal:       #0ea5a0;
  --color-teal-dark:  #0c8c88;
  --color-teal-light: #e0f7f6;
  --color-white:      #ffffff;
  --color-gray-50:    #f8fafc;
  --color-gray-100:   #f1f5f9;
  --color-gray-200:   #e2e8f0;
  --color-gray-300:   #cbd5e1;
  --color-gray-400:   #94a3b8;
  --color-gray-500:   #64748b;
  --color-gray-600:   #475569;
  --color-gray-700:   #334155;
  --color-gray-800:   #1e293b;
  --color-gray-900:   #0f172a;

  /* Typography */
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* Font Sizes */
  --text-xs:   0.75rem;
  --text-sm:   0.875rem;
  --text-base: 1rem;
  --text-lg:   1.125rem;
  --text-xl:   1.25rem;
  --text-2xl:  1.5rem;
  --text-3xl:  1.875rem;
  --text-4xl:  2.25rem;
  --text-5xl:  3rem;

  /* Spacing */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout */
  --max-width: 1200px;
  --max-width-narrow: 800px;

  /* Borders & Radius */
  --radius-sm:  0.375rem;
  --radius-md:  0.5rem;
  --radius-lg:  0.75rem;
  --radius-xl:  1rem;
  --radius-full: 9999px;

  /* Shadows */
  --shadow-sm:  0 1px 2px 0 rgba(0,0,0,0.05);
  --shadow-md:  0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg:  0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
  --shadow-xl:  0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;
}


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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-gray-700);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--color-teal);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-teal-dark);
}

h1, h2, h3, h4, h5, h6 {
  color: var(--color-navy);
  line-height: 1.2;
  font-weight: 700;
}

h1 { font-size: var(--text-5xl); }
h2 { font-size: var(--text-4xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl);  }

p + p { margin-top: var(--space-4); }


/* --- Layout Utilities --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-6);
  padding-right: var(--space-6);
}

.container--narrow {
  max-width: var(--max-width-narrow);
}

.section {
  padding-top: var(--space-20);
  padding-bottom: var(--space-20);
}

.section--gray {
  background-color: var(--color-gray-50);
}

.section--navy {
  background-color: var(--color-navy);
  color: var(--color-gray-200);
}

.section--navy h2,
.section--navy h3,
.section--navy h4 {
  color: var(--color-white);
}

.grid {
  display: grid;
  gap: var(--space-8);
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

.text-center { text-align: center; }
.text-left   { text-align: left; }

.mt-4  { margin-top: var(--space-4); }
.mt-6  { margin-top: var(--space-6); }
.mt-8  { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }
.mb-4  { margin-bottom: var(--space-4); }
.mb-6  { margin-bottom: var(--space-6); }
.mb-8  { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }


/* --- Navigation --- */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-gray-200);
  padding: var(--space-4) 0;
}

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

.nav__logo img {
  height: 36px;
  width: auto;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  list-style: none;
}

.nav__links a {
  color: var(--color-gray-600);
  font-size: var(--text-sm);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: color var(--transition-fast);
}

.nav__links a:hover,
.nav__links a.active {
  color: var(--color-teal);
}

.nav__toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
}

.nav__toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-navy);
  margin: 5px 0;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav__toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav__toggle.open span:nth-child(2) {
  opacity: 0;
}
.nav__toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}


/* --- Buttons --- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-3) var(--space-6);
  font-size: var(--text-sm);
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  line-height: 1.5;
}

.btn--primary {
  background-color: var(--color-teal);
  color: var(--color-white);
  border-color: var(--color-teal);
}

.btn--primary:hover {
  background-color: var(--color-teal-dark);
  border-color: var(--color-teal-dark);
  color: var(--color-white);
}

.btn--outline {
  background-color: transparent;
  color: var(--color-teal);
  border-color: var(--color-teal);
}

.btn--outline:hover {
  background-color: var(--color-teal);
  color: var(--color-white);
}

.btn--white {
  background-color: var(--color-white);
  color: var(--color-navy);
  border-color: var(--color-white);
}

.btn--white:hover {
  background-color: var(--color-gray-100);
  border-color: var(--color-gray-100);
}

.btn--lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-base);
}


/* --- Hero --- */
.hero {
  background-color: var(--color-navy);
  color: var(--color-gray-200);
  padding: var(--space-24) 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(14,165,160,0.15) 0%, transparent 70%);
  border-radius: 50%;
}

.hero__content {
  position: relative;
  z-index: 1;
  max-width: 720px;
}

.hero h1 {
  color: var(--color-white);
  margin-bottom: var(--space-6);
  font-size: var(--text-5xl);
  line-height: 1.1;
}

.hero p {
  font-size: var(--text-lg);
  margin-bottom: var(--space-8);
  color: var(--color-gray-300);
  max-width: 600px;
}

.hero__actions {
  display: flex;
  gap: var(--space-4);
  flex-wrap: wrap;
}


/* --- Section Headers --- */
.section-header {
  margin-bottom: var(--space-12);
}

.section-header__label {
  display: inline-block;
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-teal);
  margin-bottom: var(--space-3);
}

.section-header h2 {
  margin-bottom: var(--space-4);
}

.section-header p {
  font-size: var(--text-lg);
  color: var(--color-gray-500);
  max-width: 600px;
}

.section-header.text-center p {
  margin-left: auto;
  margin-right: auto;
}


/* --- Cards --- */
.card {
  background: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.card__icon {
  width: 48px;
  height: 48px;
  background-color: var(--color-teal-light);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-5);
  color: var(--color-teal);
  font-size: var(--text-2xl);
}

.card h3 {
  margin-bottom: var(--space-3);
  font-size: var(--text-xl);
}

.card p {
  color: var(--color-gray-500);
  font-size: var(--text-sm);
  line-height: 1.7;
}


/* --- Partner Logos --- */
.partners-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: var(--space-6);
  align-items: center;
  justify-items: center;
}

.partners-grid img {
  max-height: 56px;
  width: auto;
  filter: grayscale(100%);
  opacity: 0.6;
  transition: all var(--transition-base);
}

.partners-grid img:hover {
  filter: grayscale(0%);
  opacity: 1;
}


/* --- Featured Project --- */
.featured-project {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: center;
}

.featured-project__image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.featured-project__image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.featured-project__content h3 {
  font-size: var(--text-3xl);
  margin-bottom: var(--space-4);
}

.featured-project__content p {
  color: var(--color-gray-500);
  margin-bottom: var(--space-6);
}


/* --- FAQ / Accordion --- */
.faq-list {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--color-gray-200);
}

.faq-item__question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-5) 0;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-navy);
  text-align: left;
  line-height: 1.4;
}

.faq-item__question:hover {
  color: var(--color-teal);
}

.faq-item__icon {
  flex-shrink: 0;
  width: 24px;
  height: 24px;
  margin-left: var(--space-4);
  transition: transform var(--transition-base);
  color: var(--color-gray-400);
}

.faq-item.open .faq-item__icon {
  transform: rotate(45deg);
  color: var(--color-teal);
}

.faq-item__answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.faq-item.open .faq-item__answer {
  max-height: 500px;
}

.faq-item__answer p {
  padding-bottom: var(--space-5);
  color: var(--color-gray-500);
  font-size: var(--text-sm);
  line-height: 1.7;
}


/* --- CTA Banner --- */
.cta-banner {
  background: linear-gradient(135deg, var(--color-navy) 0%, var(--color-navy-light) 100%);
  border-radius: var(--radius-xl);
  padding: var(--space-16);
  text-align: center;
  color: var(--color-gray-200);
}

.cta-banner h2 {
  color: var(--color-white);
  margin-bottom: var(--space-4);
}

.cta-banner p {
  margin-bottom: var(--space-8);
  font-size: var(--text-lg);
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}


/* --- Testimonials --- */
.testimonial {
  background: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
}

.testimonial__quote {
  font-size: var(--text-sm);
  line-height: 1.8;
  color: var(--color-gray-600);
  margin-bottom: var(--space-6);
  font-style: italic;
  position: relative;
  padding-left: var(--space-5);
  border-left: 3px solid var(--color-teal);
}

.testimonial__author {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.testimonial__avatar {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-full);
  object-fit: cover;
}

.testimonial__name {
  font-weight: 600;
  color: var(--color-navy);
  font-size: var(--text-sm);
}

.testimonial__role {
  font-size: var(--text-xs);
  color: var(--color-gray-400);
}


/* --- About Page --- */
.about-intro {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: start;
}

.about-intro__image {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.principles-list {
  list-style: none;
  display: grid;
  gap: var(--space-4);
}

.principles-list li {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-gray-600);
}

.principles-list li::before {
  content: '→';
  color: var(--color-teal);
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 1px;
}


/* --- Contact Form --- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-12);
  align-items: start;
}

.form-group {
  margin-bottom: var(--space-5);
}

.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-navy);
  margin-bottom: var(--space-2);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-size: var(--text-base);
  color: var(--color-gray-700);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  background: var(--color-white);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-teal);
  box-shadow: 0 0 0 3px rgba(14,165,160,0.15);
}

.form-group textarea {
  min-height: 160px;
  resize: vertical;
}

.form-success {
  display: none;
  padding: var(--space-4);
  background-color: var(--color-teal-light);
  color: var(--color-teal-dark);
  border-radius: var(--radius-md);
  font-weight: 500;
  text-align: center;
}

.contact-info h3 {
  margin-bottom: var(--space-4);
}

.contact-info p {
  color: var(--color-gray-500);
  margin-bottom: var(--space-6);
}

.contact-info__email {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-teal);
}


/* --- Project Detail --- */
.project-hero {
  background: linear-gradient(135deg, var(--color-navy) 0%, var(--color-navy-light) 100%);
  color: var(--color-gray-200);
  padding: var(--space-16) 0;
}

.project-hero h1 {
  color: var(--color-white);
  font-size: var(--text-4xl);
  max-width: 720px;
}

.project-content {
  padding: var(--space-16) 0;
}

.project-content h2 {
  font-size: var(--text-2xl);
  margin-top: var(--space-10);
  margin-bottom: var(--space-4);
}

.project-content h2:first-child {
  margin-top: 0;
}

.project-content p {
  margin-bottom: var(--space-4);
  max-width: 720px;
}

.project-content ul {
  margin-left: var(--space-6);
  margin-bottom: var(--space-6);
  color: var(--color-gray-600);
}

.project-content li {
  margin-bottom: var(--space-2);
  line-height: 1.7;
}


/* --- Projects Grid --- */
.projects-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
}

.project-card {
  background: var(--color-white);
  border: 1px solid var(--color-gray-200);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: box-shadow var(--transition-base), transform var(--transition-base);
  display: flex;
  flex-direction: column;
}

.project-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.project-card__client {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.project-card__client-logo {
  height: 24px;
  width: auto;
  flex-shrink: 0;
}

.project-card__client-name {
  font-size: var(--text-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-teal);
}

.project-card h3 {
  font-size: var(--text-lg);
  margin-bottom: var(--space-3);
  line-height: 1.3;
}

.project-card p {
  color: var(--color-gray-500);
  font-size: var(--text-sm);
  line-height: 1.7;
  flex-grow: 1;
}

.project-card__link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-teal);
  margin-top: var(--space-5);
}

.project-card__link:hover {
  color: var(--color-teal-dark);
}

.project-card__services {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-4);
}

.project-card__tag {
  font-size: var(--text-xs);
  background-color: var(--color-gray-100);
  color: var(--color-gray-600);
  padding: var(--space-1) var(--space-3);
  border-radius: var(--radius-full);
}

/* --- Project Page Meta --- */
.project-meta {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--color-gray-200);
}

.project-meta__client {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.project-meta__client img {
  height: 32px;
  width: auto;
}

.project-meta__client span {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-navy);
}

/* --- Projects Page Filter (future) --- */
.projects-filter {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-bottom: var(--space-10);
}

.projects-filter__btn {
  padding: var(--space-2) var(--space-5);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--radius-full);
  background: var(--color-white);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-gray-600);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.projects-filter__btn:hover,
.projects-filter__btn.active {
  background-color: var(--color-teal);
  border-color: var(--color-teal);
  color: var(--color-white);
}


/* --- Footer --- */
.footer {
  background-color: var(--color-navy);
  color: var(--color-gray-400);
  padding: var(--space-12) 0;
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.footer__logo img {
  height: 28px;
  width: auto;
  filter: brightness(0) invert(1);
  opacity: 0.7;
}

.footer__links {
  display: flex;
  gap: var(--space-6);
  list-style: none;
}

.footer__links a {
  color: var(--color-gray-400);
  font-size: var(--text-sm);
}

.footer__links a:hover {
  color: var(--color-teal);
}

.footer__copy {
  font-size: var(--text-xs);
  color: var(--color-gray-500);
  width: 100%;
  text-align: center;
  margin-top: var(--space-8);
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-navy-light);
}


/* --- Stats --- */
.stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-8);
  text-align: center;
}

.stat__number {
  font-size: var(--text-4xl);
  font-weight: 800;
  color: var(--color-teal);
  line-height: 1;
  margin-bottom: var(--space-2);
}

.stat__label {
  font-size: var(--text-sm);
  color: var(--color-gray-400);
}


/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 968px) {
  .grid--3 { grid-template-columns: repeat(2, 1fr); }
  .grid--4 { grid-template-columns: repeat(2, 1fr); }
  .projects-grid { grid-template-columns: repeat(2, 1fr); }
  .featured-project { grid-template-columns: 1fr; }
  .about-intro { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .stats { grid-template-columns: repeat(3, 1fr); }

  h1 { font-size: var(--text-4xl); }
  h2 { font-size: var(--text-3xl); }
}

@media (max-width: 768px) {
  .nav__links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-white);
    flex-direction: column;
    padding: var(--space-6);
    border-bottom: 1px solid var(--color-gray-200);
    box-shadow: var(--shadow-lg);
    gap: var(--space-4);
  }

  .nav__links.open {
    display: flex;
  }

  .nav__toggle {
    display: block;
  }

  .grid--2,
  .grid--3,
  .grid--4,
  .projects-grid {
    grid-template-columns: 1fr;
  }

  .hero { padding: var(--space-16) 0; }
  .hero h1 { font-size: var(--text-3xl); }
  .section { padding-top: var(--space-12); padding-bottom: var(--space-12); }

  .cta-banner { padding: var(--space-10); }

  .partners-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .stats { grid-template-columns: 1fr; gap: var(--space-6); }

  .footer__inner { flex-direction: column; text-align: center; }
}

@media (max-width: 480px) {
  .partners-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .hero__actions { flex-direction: column; }
  .hero__actions .btn { width: 100%; }
}