/* =========================================================
   R3R Management Consulting — Site Styles
   Design: white background, deep-blue / charcoal ink,
   restrained & international. No flashy animation.
   ========================================================= */

:root {
  --color-bg: #ffffff;
  --color-surface: #f0f7ff;    /* cool blue-grey tint */
  --color-surface-2: #e6f2ff;
  --color-ink: #16202a;        /* charcoal */
  --color-muted: #556c82;
  --color-line: #d8e7f5;
  --color-accent: #0073ff;     /* bright blue */
  --color-accent-2: #00c6ff;   /* cyan */
  --color-accent-soft: #e0f0ff;

  --gradient-primary: linear-gradient(135deg, #004aad 0%, #0073ff 50%, #00c6ff 100%);
  --gradient-hero: linear-gradient(180deg, #ffffff 0%, #f0f8ff 100%);

  --maxw: 1120px;
  --radius: 10px;
  --gap: 24px;

  --font-sans: "Inter", "Helvetica Neue", "Helvetica Now", -apple-system,
    BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", Arial,
    sans-serif;
  --shadow-sm: 0 1px 2px rgba(16, 32, 42, 0.06);
  --shadow-md: 0 6px 24px rgba(16, 32, 42, 0.08);
  --transition: 160ms ease;
}

/* ---------- Reset ---------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}
body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--color-ink);
  background: var(--color-bg);
  line-height: 1.65;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
img,
svg {
  max-width: 100%;
  display: block;
}
a {
  color: var(--color-accent);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
h1,
h2,
h3,
h4 {
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--color-ink);
  margin: 0 0 0.5em;
}
h1 {
  font-size: clamp(2rem, 4.5vw, 3.1rem);
}
h2 {
  font-size: clamp(1.5rem, 3vw, 2.1rem);
}
h3 {
  font-size: 1.2rem;
}
p {
  margin: 0 0 1em;
}
ul {
  margin: 0 0 1em;
  padding-left: 1.15em;
}
li {
  margin: 0.35em 0;
}

/* ---------- Layout helpers ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}
.section {
  padding: 72px 0;
}
.section--surface {
  background: var(--color-surface);
}
.section--tight {
  padding: 48px 0;
}
.eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #0088ff;
  font-weight: 700;
  margin-bottom: 0.6em;
}
.lead {
  font-size: 1.12rem;
  color: var(--color-muted);
  max-width: 60ch;
}
.muted {
  color: var(--color-muted);
}

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(8px);
  border-bottom: 1px solid var(--color-line);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  color: var(--color-ink);
  letter-spacing: 0.02em;
}
.brand:hover {
  text-decoration: none;
}
.brand .logo {
  width: 30px;
  height: 30px;
}
.brand .brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}
.brand .brand-name {
  font-size: 1.02rem;
}
.brand .brand-sub {
  font-size: 0.7rem;
  color: var(--color-muted);
  font-weight: 500;
  letter-spacing: 0.06em;
}
.nav-menu {
  display: flex;
  align-items: center;
  gap: 28px;
}
.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a {
  color: var(--color-ink);
  font-size: 0.95rem;
  font-weight: 500;
}
.nav-links a:hover,
.nav-links a.active {
  color: var(--color-accent);
  text-decoration: none;
}
.nav-right {
  display: flex;
  align-items: center;
  gap: 14px;
}
.lang-toggle {
  border: 1px solid var(--color-line);
  background: var(--color-bg);
  color: var(--color-ink);
  font: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  padding: 6px 12px;
  border-radius: 999px;
  cursor: pointer;
  transition: var(--transition);
}
.lang-toggle:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  border: 0;
  background: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 22px;
  height: 2px;
  background: var(--color-ink);
  display: block;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  font-weight: 600;
  font-size: 0.98rem;
  padding: 12px 22px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  cursor: pointer;
  transition: var(--transition);
  text-align: center;
}
.btn:hover {
  text-decoration: none;
}
.btn--primary {
  background: var(--gradient-primary);
  background-size: 200% 200%;
  color: #fff;
}
.btn--primary:hover {
  filter: brightness(1.08);
}
.btn--ghost {
  background: transparent;
  color: var(--color-accent);
  border-color: var(--color-accent);
}
.btn--ghost:hover {
  background: var(--color-accent-soft);
}

/* ---------- Hero ---------- */
.hero {
  padding: 84px 0 64px;
  background: var(--gradient-hero);
  border-bottom: 1px solid var(--color-line);
}
.hero h1 {
  max-width: 16ch;
}
.hero .lead {
  margin-top: 1.2em;
  max-width: 56ch;
}

/* ---------- Cards / Grid ---------- */
.grid {
  display: grid;
  gap: var(--gap);
}
.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}
.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}
.card {
  background: var(--color-bg);
  border: 1px solid var(--color-line);
  border-radius: var(--radius);
  padding: 26px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}
.card:hover {
  box-shadow: var(--shadow-md);
  border-color: #b3d7ff;
}
.card .card-icon {
  width: 40px;
  height: 40px;
  margin-bottom: 14px;
  color: var(--color-accent);
}
.card h3 {
  margin-bottom: 0.4em;
}
.card p {
  color: var(--color-muted);
  margin-bottom: 0;
  font-size: 0.98rem;
}

/* ---------- Why list ---------- */
.checklist {
  list-style: none;
  padding: 0;
  margin: 0;
}
.checklist li {
  position: relative;
  padding-left: 30px;
  margin: 0.7em 0;
}
.checklist li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.5em;
  width: 16px;
  height: 16px;
  border-radius: 4px;
  background: var(--color-accent-soft);
  border: 1px solid var(--color-accent);
}
.checklist li::after {
  content: "";
  position: absolute;
  left: 5px;
  top: 0.55em;
  width: 6px;
  height: 10px;
  border: solid var(--color-accent);
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

/* ---------- Service detail blocks ---------- */
.service-block {
  border-top: 1px solid var(--color-line);
  padding-top: 40px;
  margin-top: 40px;
}
.service-block:first-of-type {
  border-top: 0;
  padding-top: 0;
  margin-top: 0;
}
.service-block .num {
  font-size: 0.8rem;
  color: var(--color-accent);
  font-weight: 700;
  letter-spacing: 0.12em;
}

/* ---------- CTA band ---------- */
.cta-band {
  background: var(--gradient-primary);
  color: #fff;
  border-radius: var(--radius);
  padding: 44px 36px;
  text-align: center;
}
.cta-band h2 {
  color: #fff;
}
.cta-band p {
  color: rgba(255, 255, 255, 0.85);
  max-width: 52ch;
  margin: 0 auto 1.4em;
}

/* ---------- Contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}
.contact-info p {
  color: var(--color-muted);
}
.contact-info .label {
  font-weight: 600;
  color: var(--color-ink);
  display: block;
  margin-bottom: 2px;
}
.form-field {
  margin-bottom: 18px;
}
.form-field label {
  display: block;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 6px;
}
.form-field input,
.form-field textarea,
.form-field select {
  width: 100%;
  font: inherit;
  font-size: 0.98rem;
  padding: 11px 13px;
  border: 1px solid var(--color-line);
  border-radius: 8px;
  background: #fff;
  color: var(--color-ink);
  transition: var(--transition);
}
.form-field input:focus,
.form-field textarea:focus,
.form-field select:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}
.form-field textarea {
  min-height: 130px;
  resize: vertical;
}
.form-note {
  font-size: 0.82rem;
  color: var(--color-muted);
  margin-top: 10px;
}
.form-status {
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: 8px;
  font-size: 0.92rem;
  display: none;
}
.form-status.ok {
  display: block;
  background: #e8f3ec;
  color: #1d4d3a;
  border: 1px solid #bfe0cd;
}
.form-status.err {
  display: block;
  background: #fbeaea;
  color: #8a2b2b;
  border: 1px solid #f0c8c8;
}

/* ---------- Footer ---------- */
.site-footer {
  position: relative;
  border-top: 1px solid var(--color-line);
  background: var(--color-surface);
  padding: 40px 0 28px;
  font-size: 0.9rem;
  color: var(--color-muted);
}
.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-primary);
}
.footer-grid {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
}
.footer-grid a {
  color: var(--color-muted);
}
.footer-grid a:hover {
  color: var(--color-accent);
}
.footer-bottom {
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px solid var(--color-line);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

/* ---------- 404 ---------- */
.notfound {
  text-align: center;
  padding: 120px 0;
}

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
  .grid-3 {
    grid-template-columns: 1fr;
  }
  .grid-2,
  .contact-grid {
    grid-template-columns: 1fr;
  }
  .nav-links {
    position: fixed;
    inset: 64px 0 auto 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--color-line);
    padding: 8px 20px 16px;
    transform: translateY(-120%);
    transition: transform 200ms ease;
    box-shadow: var(--shadow-md);
  }
  .nav-links.open {
    transform: translateY(0);
  }
  .nav-links li {
    padding: 10px 0;
    border-bottom: 1px solid var(--color-line);
  }
  .nav-links li:last-child {
    border-bottom: 0;
  }
  .nav-toggle {
    display: flex;
  }
  .section {
    padding: 56px 0;
  }
}

@media (max-width: 480px) {
  body {
    font-size: 16px;
  }
  .hero {
    padding: 60px 0 48px;
  }
  .cta-band {
    padding: 32px 22px;
  }
}

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