/* ─────────────────────────────────────────────────────────────────────────────
   Keep IT Simple — Design System
   Dark technical aesthetic, production-ready CSS
   ───────────────────────────────────────────────────────────────────────────── */

/* ─── Custom Properties ──────────────────────────────────────────────────── */
:root {
  /* Colour palette */
  --color-bg:           #0d1117;
  --color-surface:      #161b22;
  --color-surface-2:    #1c2128;
  --color-border:       #21262d;
  --color-border-hover: #30363d;

  --color-text:         #e6edf3;
  --color-text-muted:   #7d8590;
  --color-text-dim:     #484f58;

  --color-accent-blue:  #58a6ff;
  --color-accent-green: #3fb950;
  --color-accent-purple:#bc8cff;
  --color-accent-yellow:#d29922;

  /* Typography */
  --font-sans:  "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono:  "JetBrains Mono", "Cascadia Code", "Fira Code", "Consolas", monospace;

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

  /* Layout */
  --max-width: 1200px;
  --nav-height: 64px;

  /* Animation */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);

  /* Border radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { cursor: pointer; font: inherit; }

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

.accent { color: var(--color-accent-blue); }

/* ─── Reveal animation ───────────────────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s var(--ease-out), transform 0.6s var(--ease-out);
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ─── Buttons ────────────────────────────────────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 0.625rem 1.375rem;
  border-radius: var(--radius-md);
  font-size: 0.9375rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  border: 1px solid transparent;
  transition: background-color 0.15s var(--ease-in-out),
              border-color 0.15s var(--ease-in-out),
              color 0.15s var(--ease-in-out),
              box-shadow 0.15s var(--ease-in-out);
  white-space: nowrap;
  text-decoration: none;
}

.btn--primary {
  background-color: var(--color-accent-blue);
  border-color: var(--color-accent-blue);
  color: var(--color-bg);
  font-weight: 600;
}
.btn--primary:hover,
.btn--primary:focus-visible {
  background-color: #79b8ff;
  border-color: #79b8ff;
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.25);
  outline: none;
}

.btn--ghost {
  background-color: transparent;
  border-color: var(--color-border-hover);
  color: var(--color-text);
}
.btn--ghost:hover,
.btn--ghost:focus-visible {
  border-color: var(--color-text-muted);
  background-color: var(--color-surface);
  outline: none;
}

.btn--full { width: 100%; }

.btn-spinner {
  display: none;
  width: 1rem;
  height: 1rem;
  border: 2px solid rgba(13, 17, 23, 0.3);
  border-top-color: var(--color-bg);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

.btn.is-loading .btn-label { display: none; }
.btn.is-loading .btn-spinner { display: block; }

@keyframes spin { to { transform: rotate(360deg); } }

/* ─── Navigation ─────────────────────────────────────────────────────────── */
.nav-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  background-color: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s var(--ease-in-out);
}

.nav-header.is-scrolled {
  border-bottom-color: var(--color-border);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.nav-logo {
  font-family: var(--font-mono);
  font-size: 1.125rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  color: var(--color-text);
  transition: color 0.15s;
}
.nav-logo:hover { color: var(--color-accent-blue); }

.logo-bracket { color: var(--color-accent-blue); }
.logo-text    { color: var(--color-text); }

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.nav-link {
  font-size: 0.9375rem;
  font-weight: 400;
  color: var(--color-text-muted);
  transition: color 0.15s;
}
.nav-link:hover { color: var(--color-text); }

.nav-link--cta {
  padding: 0.4rem 1rem;
  border: 1px solid var(--color-border-hover);
  border-radius: var(--radius-md);
  color: var(--color-accent-blue);
  font-weight: 500;
  transition: border-color 0.15s, background-color 0.15s;
}
.nav-link--cta:hover {
  border-color: var(--color-accent-blue);
  background-color: rgba(88, 166, 255, 0.08);
  color: var(--color-accent-blue);
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  background: none;
  border: none;
  padding: var(--space-2);
  width: 44px;
  height: 44px;
}
.nav-toggle span {
  display: block;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: transform 0.25s var(--ease-out), opacity 0.25s;
}
.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ─── Hero ───────────────────────────────────────────────────────────────── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: var(--nav-height);
  overflow: clip;
}

/* Subtle dot-grid background */
.hero-grid-bg {
  position: absolute;
  inset: 0;
  background-image:
    radial-gradient(circle at 25% 25%, rgba(88, 166, 255, 0.06) 0%, transparent 50%),
    radial-gradient(circle at 75% 75%, rgba(63, 185, 80, 0.04) 0%, transparent 50%),
    radial-gradient(var(--color-border) 1px, transparent 1px);
  background-size: auto, auto, 32px 32px;
  pointer-events: none;
}

.hero-content {
  position: relative;
  padding-block: var(--space-24);
  max-width: 780px;
}

.hero-eyebrow {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.terminal-prefix { color: var(--color-accent-green); }
.prompt-symbol   { color: var(--color-accent-blue); }
.terminal-cmd    { color: var(--color-text); }

.cursor {
  display: inline-block;
  width: 0.55em;
  height: 1.1em;
  background-color: var(--color-accent-blue);
  vertical-align: text-bottom;
  animation: blink 1.1s step-end infinite;
  border-radius: 1px;
}
@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

.hero-heading {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 300;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--color-text);
  margin-bottom: var(--space-6);
}

.hero-sub {
  font-size: clamp(1rem, 2vw, 1.1875rem);
  line-height: 1.7;
  color: var(--color-text-muted);
  max-width: 600px;
  margin-bottom: var(--space-8);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-bottom: var(--space-12);
}

.hero-meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
}
.meta-label {
  color: var(--color-text-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.meta-value {
  color: var(--color-text-muted);
  padding: var(--space-1) var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: 20px;
  background-color: var(--color-surface);
}

/* Scroll hint chevron */
.hero-scroll-hint {
  position: absolute;
  bottom: var(--space-8);
  left: 50%;
  transform: translateX(-50%);
}
.hero-scroll-hint span {
  display: block;
  width: 20px;
  height: 20px;
  border-right: 2px solid var(--color-text-dim);
  border-bottom: 2px solid var(--color-text-dim);
  transform: rotate(45deg);
  animation: bounce-down 2s ease-in-out infinite;
}
@keyframes bounce-down {
  0%, 100% { transform: rotate(45deg) translateY(0); }
  50%       { transform: rotate(45deg) translateY(6px); }
}

/* ─── Section Shared ─────────────────────────────────────────────────────── */
.section {
  padding-block: var(--space-24);
}
.section--alt {
  background-color: var(--color-surface);
}

.section-header {
  max-width: 640px;
  margin-bottom: var(--space-16);
}

.section-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent-blue);
  margin-bottom: var(--space-3);
}

.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 300;
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--color-text);
}

/* ─── Services Grid ──────────────────────────────────────────────────────── */
.services-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(min(340px, 100%), 1fr));
  gap: var(--space-4);
}

.card {
  position: relative;
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8) var(--space-6) var(--space-6);
  overflow: hidden;
  transition: border-color 0.2s var(--ease-in-out),
              background-color 0.2s var(--ease-in-out);
}
.card:hover {
  border-color: var(--color-border-hover);
  background-color: var(--color-surface-2);
}

/* Top accent bar */
.card-accent {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
}
.card-accent--blue   { background-color: var(--color-accent-blue); }
.card-accent--green  { background-color: var(--color-accent-green); }
.card-accent--purple { background-color: var(--color-accent-purple); }
.card-accent--yellow { background-color: var(--color-accent-yellow); }

.card-icon {
  width: 40px;
  height: 40px;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.card-title {
  font-size: 1.0625rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.card-body {
  font-size: 0.9375rem;
  line-height: 1.65;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}
.card-tags li {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-dim);
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  padding: 2px 8px;
}

/* ─── Process Steps ──────────────────────────────────────────────────────── */
.process-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
  max-width: 720px;
  margin-inline: auto;
}

.process-step {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: var(--space-6);
  align-items: start;
  position: relative;
}

.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background-color: var(--color-bg);
  flex-shrink: 0;
}
.step-number span {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-accent-blue);
}

.step-content {
  padding-top: var(--space-3);
  padding-bottom: var(--space-12);
}

.step-title {
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.step-body {
  font-size: 0.9375rem;
  line-height: 1.7;
  color: var(--color-text-muted);
}

/* Vertical connector line between steps */
.step-connector {
  position: absolute;
  left: calc(52px / 2);
  top: 52px;
  bottom: 0;
  width: 1px;
  background: linear-gradient(to bottom, var(--color-border) 0%, transparent 100%);
}

/* ─── About ──────────────────────────────────────────────────────────────── */
.about-layout {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: var(--space-20);
  align-items: center;
}

.about-body {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--color-text-muted);
  margin-top: var(--space-6);
}
.about-body + .about-body {
  margin-top: var(--space-4);
}

.about-stats {
  display: flex;
  flex-direction: column;
  gap: var(--space-8);
  flex-shrink: 0;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: var(--space-1);
}
.stat-value {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 500;
  letter-spacing: -0.02em;
}
.stat-dot { opacity: 0.4; }
.stat-label {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* ─── Contact ────────────────────────────────────────────────────────────── */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-20);
  align-items: start;
}

.contact-subtext {
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-text-muted);
  margin-top: var(--space-4);
  margin-bottom: var(--space-8);
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}
.contact-details li {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  min-height: 44px;
}
.contact-details a,
.contact-details span {
  padding-block: 0.5rem;
  display: inline-block;
}
.contact-details a {
  color: var(--color-text-muted);
  transition: color 0.15s;
}
.contact-details a:hover { color: var(--color-accent-blue); }
.contact-icon {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  color: var(--color-text-dim);
}

/* Form */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form-label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text-muted);
}
.form-optional {
  font-weight: 400;
  color: var(--color-text-dim);
  font-size: 0.8125rem;
}

.form-input {
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  padding: 0.625rem 0.875rem;
  width: 100%;
  transition: border-color 0.15s, box-shadow 0.15s;
  outline: none;
}
.form-input::placeholder { color: var(--color-text-dim); }
.form-input:hover        { border-color: var(--color-border-hover); }
.form-input:focus        {
  border-color: var(--color-accent-blue);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.15);
}
.form-input.is-invalid   { border-color: #f85149; }
.form-input.is-invalid:focus {
  box-shadow: 0 0 0 3px rgba(248, 81, 73, 0.15);
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

.form-error {
  font-size: 0.8125rem;
  color: #f85149;
  min-height: 1.2em;
}

.form-status {
  font-size: 0.875rem;
  text-align: center;
  min-height: 1.4em;
}
.form-status.is-success { color: var(--color-accent-green); }
.form-status.is-error   { color: #f85149; }

/* ─── Footer ─────────────────────────────────────────────────────────────── */
.site-footer {
  background-color: var(--color-bg);
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-8);
}

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

.footer-logo {
  font-family: var(--font-mono);
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text-muted);
}

.footer-copy {
  font-size: 0.875rem;
  color: var(--color-text-dim);
}

.footer-nav {
  display: flex;
  gap: var(--space-6);
}
.footer-nav a {
  font-size: 0.875rem;
  color: var(--color-text-dim);
  transition: color 0.15s;
}
.footer-nav a:hover { color: var(--color-text-muted); }

/* ─── Responsive ─────────────────────────────────────────────────────────── */
@media (max-width: 900px) {
  .about-layout {
    grid-template-columns: 1fr;
    gap: var(--space-12);
  }
  .about-stats {
    flex-direction: row;
    justify-content: flex-start;
    align-items: flex-start;
  }
  .stat { align-items: flex-start; }

  .contact-layout {
    grid-template-columns: 1fr;
    gap: var(--space-12);
  }

  .services-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  :root { --space-24: 4rem; --space-20: 3rem; --space-16: 2.5rem; }

  .nav-toggle { display: flex; }

  .nav-links {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    z-index: 99;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-4) var(--space-6) var(--space-6);
    transform: translateY(-110%);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.3s var(--ease-out), opacity 0.3s;
  }
  .nav-links.is-open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  .nav-links li {
    border-bottom: 1px solid var(--color-border);
  }
  .nav-links li:last-child { border-bottom: none; }

  .nav-link {
    display: block;
    padding-block: var(--space-4);
    color: var(--color-text);
  }
  .nav-link--cta {
    border: none;
    border-radius: 0;
    padding-inline: 0;
    color: var(--color-accent-blue);
    background: none;
  }
  .nav-link--cta:hover,
  .nav-link--cta:active {
    background: none;
    color: #79b8ff;
  }

  .hero-heading { font-size: clamp(2rem, 9vw, 3rem); }

  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-nav {
    flex-direction: column;
    gap: var(--space-2);
  }
  .footer-nav a {
    padding-block: 0.5rem;
    display: inline-block;
  }

  .process-step {
    grid-template-columns: 52px 1fr;
    gap: var(--space-4);
  }
}

/* ─── Focus visible (keyboard accessibility) ─────────────────────────────── */
:focus-visible {
  outline: 2px solid var(--color-accent-blue);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* ─── Reduced motion ─────────────────────────────────────────────────────── */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  html { scroll-behavior: auto; }
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}