/* ============================================================
   ChalTech wireframes — BASE (δομή/layout, κοινό σε όλα τα designs)
   Όλα τα χρώματα, γραμματοσειρές, γωνίες κ.λπ. ορίζονται στο theme.css
   μέσω CSS tokens. Το base.css δεν περιέχει design αποφάσεις.
   ============================================================ */

*, *::before, *::after { box-sizing: border-box; }

/* το smooth scrolling μόνο όταν ο χρήστης δεν έχει ζητήσει λιγότερη κίνηση */
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

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

a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }

h1, h2, h3, h4 {
  color: var(--heading);
  font-family: var(--font-display);
  font-weight: var(--display-weight, 700);
  line-height: 1.18;
  letter-spacing: var(--display-tracking, -0.015em);
  text-wrap: balance;
  margin: 0 0 0.5em;
}
h1 { font-size: clamp(2rem, 5vw, 3.1rem); }
h2 { font-size: clamp(1.5rem, 3.2vw, 2.1rem); }
h3 { font-size: 1.2rem; }

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

:focus-visible {
  outline: 2px solid var(--focus-ring);
  outline-offset: 2px;
  border-radius: 4px;
}

.skip-link {
  position: absolute;
  top: 0;
  left: -9999px;
  z-index: 100;
  background: var(--surface);
  color: var(--heading);
  font-weight: 700;
  padding: 0.7rem 1.2rem;
  border-radius: 0 0 var(--radius-sm) 0;
  box-shadow: var(--card-shadow);
}
.skip-link:focus { left: 0; }

.container {
  max-width: var(--container, 1120px);
  margin-inline: auto;
  padding-inline: clamp(1rem, 4vw, 2rem);
}

.eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent-text, var(--accent));
  margin-bottom: 0.7rem;
}

.section { padding-block: clamp(2.5rem, 7vw, 5rem); }
.section.tint { background: var(--surface-2); }
.section-head { max-width: 46rem; margin-bottom: clamp(1.4rem, 3.5vw, 2.4rem); }
.section-head p { color: var(--muted); font-size: 1.05rem; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.72rem 1.4rem;
  border-radius: var(--btn-radius, 999px);
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 700;
  cursor: pointer;
  border: 2px solid transparent;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background-color 0.15s ease, border-color 0.15s ease;
  text-decoration: none;
}
.btn:hover { text-decoration: none; }

.btn-primary {
  background: var(--btn-primary-bg);
  color: var(--btn-primary-ink);
  box-shadow: var(--btn-primary-shadow, none);
}
.btn-primary:hover { background: var(--accent-strong); transform: translateY(-1px); }

.btn-ghost {
  background: transparent;
  color: var(--heading);
  border-color: var(--btn-ghost-line);
}
.btn-ghost:hover { border-color: var(--sky); }

.btn-sm { padding: 0.5rem 1.05rem; font-size: 0.88rem; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}
.site-header.scrolled {
  border-bottom-color: var(--line);
  box-shadow: var(--header-shadow, none);
}
.header-inner { display: flex; align-items: center; gap: clamp(0.8rem, 2vw, 1.2rem); min-height: 72px; }

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-size: 1.32rem;
  font-weight: 800;
  font-family: var(--font-display);
  color: var(--heading);
  letter-spacing: -0.02em;
}
.brand:hover { text-decoration: none; }
.brand .brand-mark { height: 34px; width: auto; flex: none; }
.brand .tld { color: var(--accent); }

.main-nav { display: flex; gap: clamp(1.1rem, 2vw, 1.6rem); margin-left: auto; }
.main-nav a {
  color: var(--ink);
  font-weight: 600;
  font-size: 0.97rem;
  padding-block: 0.3rem;
  border-bottom: 2px solid transparent;
}
.main-nav a:hover { text-decoration: none; color: var(--heading); }
.main-nav a[aria-current="page"] { color: var(--heading); border-bottom-color: var(--accent-text, var(--accent)); }

.header-actions { display: flex; align-items: center; gap: 0.6rem; }

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 1.5px solid var(--btn-ghost-line);
  background: transparent;
  color: var(--heading);
  cursor: pointer;
  transition: border-color 0.15s ease;
}
.icon-btn:hover { border-color: var(--sky); }
.icon-btn svg { width: 18px; height: 18px; }

.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }
[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: block; }
  :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: none; }
}

.burger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 10px;
  background: transparent;
  border: 1.5px solid var(--btn-ghost-line);
  border-radius: var(--radius-sm);
  cursor: pointer;
}
.burger span { display: block; height: 2px; border-radius: 2px; background: var(--heading); transition: transform 0.25s ease, opacity 0.2s ease; }
body.nav-open .burger span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
body.nav-open .burger span:nth-child(2) { opacity: 0; }
body.nav-open .burger span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.mobile-nav { display: none; border-top: 1px solid var(--line); background: var(--surface); }
body.nav-open .mobile-nav { display: block; }
.mobile-nav ul { list-style: none; margin: 0; padding: 0.6rem 0 1rem; }
.mobile-nav a { display: block; padding: 0.8rem clamp(1rem, 4vw, 2rem); font-weight: 600; color: var(--ink); }
.mobile-nav a:hover { text-decoration: none; background: var(--surface-2); }
.mobile-nav .btn { margin: 0.6rem clamp(1rem, 4vw, 2rem) 0; }

@media (max-width: 880px) {
  .main-nav, .header-actions .btn, .lang-chip { display: none; }
  .burger { display: flex; margin-left: auto; }
  .header-actions { margin-left: auto; }
}

.lang-chip {
  font-size: 0.8rem;
  font-weight: 700;
  font-family: inherit;
  color: var(--muted);
  background: transparent;
  border: 1.5px dashed var(--btn-ghost-line);
  border-radius: 999px;
  padding: 0.32rem 0.7rem;
  cursor: pointer;
}
.lang-chip:hover { color: var(--heading); border-color: var(--sky); }

.mobile-nav .lang-btn {
  display: block;
  width: 100%;
  text-align: left;
  padding: 0.8rem clamp(1rem, 4vw, 2rem);
  font: inherit;
  font-weight: 600;
  color: var(--ink);
  background: transparent;
  border: 0;
  cursor: pointer;
}
.mobile-nav .lang-btn:hover { background: var(--surface-2); }

/* ---------- hero ---------- */
.hero { position: relative; overflow: hidden; padding-block: clamp(2.75rem, 8vw, 6rem) clamp(2.25rem, 6vw, 4.25rem); }
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--hero-backdrop, none);
  pointer-events: none;
}
.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: clamp(1.6rem, 4.5vw, 3.5rem);
  align-items: center;
}
.hero h1 { margin-bottom: 0.55em; }
.hero h1 .accent { color: var(--accent-text, var(--accent)); }
.hero .lede { color: var(--muted); font-size: 1.13rem; max-width: 34rem; margin-bottom: 1.6rem; }
.hero-ctas { display: flex; flex-wrap: wrap; gap: 0.8rem; }
.hero-art { position: relative; }
.hero-art img { width: 100%; max-width: 420px; height: auto; margin-inline: auto; }

.page-hero { position: relative; overflow: hidden; padding-block: clamp(2.25rem, 6vw, 3.75rem) clamp(1.5rem, 4vw, 2.5rem); }
.page-hero::before { content: ""; position: absolute; inset: 0; background: var(--hero-backdrop, none); pointer-events: none; }
.page-hero .container { position: relative; }
.page-hero .lede { color: var(--muted); font-size: 1.1rem; max-width: 40rem; }

@media (max-width: 820px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero-art { order: -1; }
  .hero-art img { max-width: 300px; }
}

/* ---------- trust strip ---------- */
.trust-strip { border-block: 1px solid var(--line); background: var(--surface); }
.trust-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem clamp(1.2rem, 3.5vw, 2.4rem);
  justify-content: center;
  padding-block: clamp(0.8rem, 2vw, 1rem);
  color: var(--muted);
  font-size: 0.93rem;
  font-weight: 600;
}
.trust-inner .dot-sep { color: var(--accent); }

/* ---------- cards ---------- */
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: clamp(1rem, 2.2vw, 1.3rem); }
.card {
  background: var(--card-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius);
  padding: 1.7rem 1.6rem 1.6rem;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.card:hover { transform: translateY(-3px); }
.card .card-icon {
  width: 46px;
  height: 46px;
  border-radius: var(--radius-sm);
  display: grid;
  place-items: center;
  background: var(--surface-2);
  color: var(--sky);
  margin-bottom: 0.4rem;
}
.card .card-icon svg { width: 24px; height: 24px; }
.card h3 { margin-bottom: 0.15rem; }
.card p { color: var(--muted); font-size: 0.96rem; flex: 1; }
.card .card-link { font-weight: 700; font-size: 0.93rem; color: var(--accent-text, var(--accent)); margin-top: 0.4rem; }

/* ---------- process steps ---------- */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: clamp(0.9rem, 2vw, 1.2rem); counter-reset: step; }
.step {
  position: relative;
  background: var(--card-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius);
  padding: 1.4rem 1.3rem 1.2rem;
}
.step::before {
  counter-increment: step;
  content: counter(step, decimal-leading-zero);
  display: block;
  font-size: 0.85rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  color: var(--accent-text, var(--accent));
  margin-bottom: 0.5rem;
}
.step h3 { font-size: 1.05rem; margin-bottom: 0.25rem; }
.step p { color: var(--muted); font-size: 0.92rem; }

/* ---------- zigzag ---------- */
.zig {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: clamp(1.5rem, 4.5vw, 3.5rem);
  align-items: center;
  padding-block: clamp(1.75rem, 4.5vw, 3rem);
}
.zig + .zig { border-top: 1px solid var(--line); }
.zig.flip .zig-media { order: -1; }
.zig h2 { margin-bottom: 0.35em; }
.zig .zig-body p { color: var(--muted); }
.zig ul.checks { list-style: none; margin: 1rem 0 1.4rem; padding: 0; display: grid; gap: 0.5rem; }
.zig ul.checks li { display: flex; gap: 0.6rem; align-items: baseline; font-weight: 600; font-size: 0.98rem; }
.zig ul.checks li::before { content: "✓"; color: var(--accent-text, var(--accent)); font-weight: 800; flex: none; }
.zig-media {
  border-radius: var(--radius);
  overflow: hidden;
  border: var(--card-border, 1px solid var(--line));
  background: var(--surface);
  box-shadow: var(--card-shadow);
}
.zig-media svg { width: 100%; height: auto; display: block; }
@media (max-width: 780px) {
  .zig { grid-template-columns: 1fr; }
  .zig.flip .zig-media { order: 0; }
  .zig-media { max-width: 460px; }
}

/* ---------- split (about) ---------- */
.split { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: clamp(1.6rem, 4.5vw, 3.5rem); align-items: center; }
.split .split-media {
  background: var(--logo-panel-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius);
  padding: clamp(1.5rem, 4vw, 2.5rem);
  display: grid;
  place-items: center;
  box-shadow: var(--card-shadow);
}
.split .split-media img { max-width: 260px; }
.split p { color: var(--muted); }
@media (max-width: 780px) {
  .split { grid-template-columns: 1fr; }
  .split .split-media { max-width: 380px; margin-inline: auto; }
}

/* ---------- CTA banner ---------- */
.cta-banner {
  background: var(--cta-bg);
  color: var(--cta-ink);
  border-radius: calc(var(--radius) + 4px);
  padding: clamp(1.6rem, 4vw, 2.75rem);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: clamp(1rem, 2.5vw, 1.4rem);
  box-shadow: var(--cta-shadow, none);
}
.cta-banner h2 { color: var(--cta-heading); margin: 0 0 0.25rem; }
.cta-banner p { color: var(--cta-muted); margin: 0; }
.cta-banner .btn-primary { flex: none; }

/* ---------- FAQ ---------- */
.faq { max-width: 46rem; }
.faq details {
  background: var(--card-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius-sm);
  margin-bottom: 0.7rem;
  overflow: hidden;
}
.faq summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  padding: 0.95rem 1.2rem;
  font-weight: 700;
  color: var(--heading);
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-size: 1.3rem; font-weight: 600; color: var(--accent-text, var(--accent)); transition: transform 0.2s ease; flex: none; }
.faq details[open] summary::after { transform: rotate(45deg); }
.faq .faq-body { padding: 0 1.2rem 1.1rem; color: var(--muted); font-size: 0.97rem; }

/* ---------- tables (άρθρο 47) ---------- */
.table-wrap {
  overflow-x: auto;
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius);
  background: var(--surface);
  box-shadow: var(--card-shadow);
}
table.info { width: 100%; border-collapse: collapse; font-size: 0.97rem; min-width: 560px; }
table.info th, table.info td { text-align: left; padding: 0.8rem 1.2rem; vertical-align: top; }
table.info th { width: 38%; color: var(--heading); font-weight: 700; background: var(--surface-2); border-right: 1px solid var(--line); }
table.info tr + tr th, table.info tr + tr td { border-top: 1px solid var(--line); }
table.info td { font-variant-numeric: tabular-nums; }

.kad-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.55rem; }
.kad-list li {
  display: flex;
  gap: 0.9rem;
  align-items: baseline;
  background: var(--card-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius-sm);
  padding: 0.7rem 1rem;
  font-size: 0.94rem;
}
.kad-list .kad-code { font-variant-numeric: tabular-nums; font-weight: 700; color: var(--heading); flex: none; }
.kad-list .kad-tag {
  margin-left: auto;
  flex: none;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.12rem 0.6rem;
  white-space: nowrap;
}
.kad-list .kad-tag.main { color: var(--accent-text, var(--accent)); border-color: var(--accent-text, var(--accent)); }
@media (max-width: 620px) {
  .kad-list li { flex-wrap: wrap; }
  .kad-list .kad-tag { margin-left: 0; }
}

/* ---------- contact ---------- */
.contact-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: clamp(0.8rem, 2vw, 1rem);
  align-items: stretch;
}
.contact-card {
  background: var(--card-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius);
  padding: 1.2rem 1.4rem;
  box-shadow: var(--card-shadow);
}
.contact-card :is(h2, h3) { font-size: 1rem; margin-bottom: 0.3rem; }
.contact-card p { color: var(--muted); font-size: 0.95rem; margin: 0; }
.contact-card a { font-weight: 700; }

/* ---------- founder ---------- */
.founder {
  display: flex;
  gap: 1.6rem;
  align-items: center;
  background: var(--card-bg, var(--surface));
  border: var(--card-border, 1px solid var(--line));
  border-radius: var(--radius);
  padding: clamp(1.4rem, 3vw, 2rem);
  box-shadow: var(--card-shadow);
  max-width: 46rem;
}
.founder .avatar {
  width: 92px;
  height: 92px;
  border-radius: 50%;
  flex: none;
  display: grid;
  place-items: center;
  background: var(--avatar-bg);
  color: var(--avatar-ink);
  font-size: 1.9rem;
  font-weight: 800;
}
.founder p { color: var(--muted); font-size: 0.97rem; }
.founder h3 { margin-bottom: 0.15rem; }
.founder .role { color: var(--accent); font-weight: 700; font-size: 0.88rem; }
@media (max-width: 560px) { .founder { flex-direction: column; text-align: center; } }

/* ---------- footer ---------- */
.site-footer { margin-top: clamp(2.5rem, 6vw, 4.25rem); border-top: 1px solid var(--line); background: var(--surface); font-size: 0.94rem; }
.footer-inner { display: grid; grid-template-columns: 1.2fr 1fr 1fr; gap: clamp(1.4rem, 3vw, 2rem); padding-block: clamp(1.8rem, 4vw, 2.4rem) clamp(1.4rem, 3vw, 1.9rem); }
.footer-inner h2 { font-size: 0.82rem; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted); margin-bottom: 0.7rem; }
.footer-inner ul { list-style: none; margin: 0; padding: 0; display: grid; gap: 0.45rem; }
.footer-inner a { color: var(--ink); }
.footer-inner a:hover { color: var(--heading); }
.footer-brand .brand { font-size: 1.15rem; }
.footer-brand p { color: var(--muted); margin-top: 0.6rem; max-width: 26ch; }
.footer-bottom {
  border-top: 1px solid var(--line);
  padding-block: 1rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  justify-content: space-between;
  color: var(--muted);
  font-size: 0.85rem;
}
@media (max-width: 720px) { .footer-inner { grid-template-columns: 1fr; gap: 1.6rem; } }

/* ---------- reveal ---------- */
.reveal { opacity: 1; transform: none; }
@media (prefers-reduced-motion: no-preference) {
  .reveal { opacity: 0; transform: translateY(18px); transition: opacity 0.55s ease, transform 0.55s ease; }
  .reveal.in { opacity: 1; transform: none; }
}

/* ---------- utility ---------- */
.center { text-align: center; }
.mt-2 { margin-top: 2rem; }
.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  margin: -1px; padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}