/* Sicherheits- & Netzwerktechnik — main stylesheet
   Mobile-first. No frameworks, no build step. */

:root {
  --color-bg: #0b1220;
  --color-bg-alt: #101a2c;
  --color-surface: #14203a;
  --color-surface-2: #1a2947;
  --color-border: #24365c;
  --color-text: #eef2f9;
  --color-text-muted: #a9b7d1;
  --color-accent: #22d3b6;
  --color-accent-strong: #17b89e;
  --color-accent-contrast: #04241d;
  --color-focus: #7cf0dd;
  --color-danger: #ff6b6b;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue",
    Arial, "Noto Sans", sans-serif, "Apple Color Emoji", "Segoe UI Emoji";

  --max-width: 1180px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 22px;

  --space-1: 0.5rem;
  --space-2: 0.75rem;
  --space-3: 1rem;
  --space-4: 1.5rem;
  --space-5: 2rem;
  --space-6: 3rem;
  --space-7: 4.5rem;
  --space-8: 6rem;

  color-scheme: dark;
}

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

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

/* Anchor targets sit far enough below the sticky header (72px) so in-page
   navigation doesn't scroll a heading underneath it. */
[id] {
  scroll-margin-top: 88px;
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: hidden;
}

img,
svg {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
}

h1,
h2,
h3,
h4 {
  line-height: 1.2;
  margin: 0 0 var(--space-3);
  font-weight: 700;
}

p {
  margin: 0 0 var(--space-3);
  color: var(--color-text-muted);
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

button {
  font: inherit;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Focus visibility (accessibility requirement — never remove without replacement) */
a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible,
[tabindex]:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.skip-link {
  position: absolute;
  left: var(--space-2);
  top: -60px;
  background: var(--color-accent);
  color: var(--color-accent-contrast);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  font-weight: 700;
  z-index: 1000;
  transition: top 0.15s ease;
}

.skip-link:focus {
  top: var(--space-2);
}

/* Layout helpers */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.section {
  padding: var(--space-7) 0;
}

.section-header {
  max-width: 700px;
  margin: 0 0 var(--space-5);
}

.section-header .eyebrow {
  display: inline-block;
  color: var(--color-accent);
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-size: 0.8rem;
  margin-bottom: var(--space-2);
}

.section-header h2 {
  font-size: clamp(1.6rem, 4vw, 2.25rem);
}

.section-header p {
  font-size: 1.05rem;
}

.section-alt {
  background: var(--color-bg-alt);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-1);
  padding: 0.85rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 700;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.12s ease, background-color 0.12s ease, border-color 0.12s ease;
  min-height: 44px;
  line-height: 1.2;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-accent-contrast);
}

.btn-primary:hover {
  background: var(--color-accent-strong);
}

.btn-secondary {
  background: transparent;
  border-color: var(--color-border);
  color: var(--color-text);
}

.btn-secondary:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.btn-block {
  width: 100%;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--color-border);
}

/* The frosted background lives on a pseudo-element rather than directly on
   .site-header: `backdrop-filter` (like `filter`) creates a new CSS
   containing block for `position: fixed` descendants, which would break the
   fullscreen mobile nav nested inside this header. A pseudo-element has no
   descendants of its own, so it can carry the effect without trapping the
   nav's fixed positioning. */
.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  background: rgba(11, 18, 32, 0.92);
  backdrop-filter: saturate(140%) blur(8px);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  height: 72px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  font-weight: 800;
  font-size: 1.1rem;
  letter-spacing: 0.01em;
  color: var(--color-text);
}

.brand img {
  width: 34px;
  height: 34px;
}

.brand .brand-sub {
  display: block;
  font-size: 0.6rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--color-accent);
  text-transform: uppercase;
}

.brand .brand-wordmark {
  display: block;
  max-width: 200px;
  font-size: clamp(0.72rem, 2.6vw, 0.95rem);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: 0.01em;
  text-transform: uppercase;
}

.nav-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text);
}

.nav-toggle svg {
  width: 22px;
  height: 22px;
}

.primary-nav {
  position: fixed;
  inset: 72px 0 0 0;
  background: var(--color-bg);
  padding: var(--space-4);
  transform: translateY(-8px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.15s ease, transform 0.15s ease;
  overflow-y: auto;
}

.primary-nav.is-open {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.primary-nav ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.primary-nav a:not(.btn) {
  display: block;
  padding: var(--space-3) var(--space-2);
  text-decoration: none;
  font-weight: 600;
  border-bottom: 1px solid var(--color-border);
}

.primary-nav .nav-cta {
  margin-top: var(--space-3);
}

@media (min-width: 900px) {
  .nav-toggle {
    display: none;
  }

  .primary-nav {
    position: static;
    inset: auto;
    background: transparent;
    padding: 0;
    opacity: 1;
    transform: none;
    pointer-events: auto;
    overflow: visible;
  }

  .primary-nav ul {
    flex-direction: row;
    align-items: center;
    gap: var(--space-4);
  }

  .primary-nav a:not(.btn) {
    padding: 0;
    border-bottom: none;
    font-size: 0.95rem;
  }

  .primary-nav .nav-cta {
    margin-top: 0;
  }
}

/* Hero */
.hero {
  padding: var(--space-8) 0 var(--space-7);
  background:
    radial-gradient(60% 60% at 85% 0%, rgba(34, 211, 182, 0.16), transparent 60%),
    var(--color-bg);
}

.hero .container {
  display: grid;
  gap: var(--space-6);
  align-items: center;
}

.hero h1 {
  font-size: clamp(2rem, 5.5vw, 3.2rem);
  max-width: 18ch;
}

.hero .lead {
  font-size: 1.1rem;
  max-width: 56ch;
}

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

.hero-tagline {
  color: var(--color-accent);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-size: 0.95rem;
  margin: 0 0 var(--space-3);
}

.trust-line {
  margin-top: var(--space-5);
  color: var(--color-text-muted);
  font-size: 0.9rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.2rem;
}

.hero-visual {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: linear-gradient(160deg, var(--color-surface), var(--color-surface-2));
  padding: var(--space-5);
  aspect-ratio: 4 / 3;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-visual svg {
  width: 100%;
  height: 100%;
}

@media (min-width: 960px) {
  .hero .container {
    grid-template-columns: 1.1fr 0.9fr;
  }
}

/* Services */
.card-grid {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .card-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1000px) {
  .card-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4);
  height: 100%;
}

.card .icon {
  width: 46px;
  height: 46px;
  border-radius: var(--radius-sm);
  background: rgba(34, 211, 182, 0.12);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-3);
}

.card .icon svg {
  width: 24px;
  height: 24px;
}

.card h4 {
  font-size: 1.1rem;
}

.card p {
  font-size: 0.95rem;
  margin-bottom: 0;
}

.service-group {
  margin-bottom: var(--space-6);
}

.service-group:last-child {
  margin-bottom: 0;
}

.service-group-title {
  font-size: 1.05rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
  padding-bottom: var(--space-2);
  margin-bottom: var(--space-3);
  border-bottom: 1px solid var(--color-border);
}

/* Why us */
.why-list {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: 1fr;
}

@media (min-width: 700px) {
  .why-list {
    grid-template-columns: repeat(2, 1fr);
  }
}

.why-item {
  display: flex;
  gap: var(--space-3);
  align-items: flex-start;
}

.why-item .icon {
  flex-shrink: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: rgba(34, 211, 182, 0.12);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
}

.why-item .icon svg {
  width: 20px;
  height: 20px;
}

.why-item h3 {
  font-size: 1rem;
  margin-bottom: 0.25rem;
}

.why-item p {
  font-size: 0.92rem;
  margin-bottom: 0;
}

/* Process */
.process-list {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
  counter-reset: step;
}

@media (min-width: 760px) {
  .process-list {
    grid-template-columns: repeat(5, 1fr);
  }
}

.process-step {
  position: relative;
  padding-top: var(--space-6);
}

.process-step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  top: 0;
  left: 0;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-accent);
  color: var(--color-accent-contrast);
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
}

.process-step h3 {
  font-size: 1rem;
}

.process-step p {
  font-size: 0.9rem;
  margin-bottom: 0;
}

/* Use cases */
.usecase-grid {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(2, 1fr);
}

@media (min-width: 640px) {
  .usecase-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 1000px) {
  .usecase-grid {
    grid-template-columns: repeat(6, 1fr);
  }
}

.usecase-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-3);
  text-align: center;
  font-size: 0.9rem;
  font-weight: 600;
}

.usecase-item .icon {
  width: 36px;
  height: 36px;
  margin: 0 auto var(--space-2);
  color: var(--color-accent);
}

/* FAQ */
.faq-list {
  max-width: 820px;
}

.faq-item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  margin-bottom: var(--space-2);
  overflow: hidden;
}

.faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: var(--space-3) var(--space-4);
  font-weight: 700;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-3);
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  color: var(--color-accent);
  font-size: 1.4rem;
  font-weight: 400;
  flex-shrink: 0;
}

.faq-item[open] summary::after {
  content: "\2212";
}

.faq-item .faq-answer {
  padding: 0 var(--space-4) var(--space-4);
  color: var(--color-text-muted);
  font-size: 0.95rem;
}

/* Contact */
.contact-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
}

@media (min-width: 900px) {
  .contact-grid {
    grid-template-columns: 0.9fr 1.1fr;
  }
}

.contact-info-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.contact-info-item {
  display: flex;
  gap: var(--space-3);
  align-items: flex-start;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-3);
}

.contact-info-item .icon {
  width: 40px;
  height: 40px;
  flex-shrink: 0;
  border-radius: 50%;
  background: rgba(34, 211, 182, 0.12);
  color: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
}

.contact-info-item .icon svg {
  width: 20px;
  height: 20px;
}

.contact-info-item h3 {
  font-size: 0.95rem;
  margin-bottom: 0.15rem;
}

.contact-info-item a,
.contact-info-item .value {
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.95rem;
}

.contact-info-item a:hover {
  color: var(--color-accent);
}

/* Form */

/* Honeypot: hidden from every real visitor (sighted or screen-reader) and
   removed from tab order. Off-screen positioning (not display:none) so
   unsophisticated bots that skip display:none fields still fill it in. */
.hp-field {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.form-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
}

.form-row {
  display: grid;
  gap: var(--space-3);
  margin-bottom: var(--space-3);
  grid-template-columns: 1fr;
}

@media (min-width: 560px) {
  .form-row.two-col {
    grid-template-columns: 1fr 1fr;
  }
}

.field label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
}

.field .hint {
  display: block;
  font-size: 0.8rem;
  color: var(--color-text-muted);
  margin-top: 0.3rem;
}

.field input,
.field select,
.field textarea {
  width: 100%;
  padding: 0.75rem 0.85rem;
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-text);
  font: inherit;
  min-height: 44px;
}

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

.field input:invalid[data-touched="true"],
.field textarea:invalid[data-touched="true"] {
  border-color: var(--color-danger);
}

.field-error {
  color: var(--color-danger);
  font-size: 0.82rem;
  margin-top: 0.3rem;
  display: none;
}

.field-error.is-visible {
  display: block;
}

.checkbox-field {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
}

.checkbox-field input {
  width: 20px;
  height: 20px;
  min-height: auto;
  flex-shrink: 0;
  margin-top: 0.15rem;
}

.checkbox-field label {
  font-size: 0.88rem;
  font-weight: 400;
  color: var(--color-text-muted);
}

.checkbox-field a {
  color: var(--color-accent);
}

.form-status {
  margin-top: var(--space-3);
  font-size: 0.9rem;
  display: none;
}

.form-status.is-visible {
  display: block;
}

.form-status.is-error {
  color: var(--color-danger);
}

.form-status.is-success {
  color: var(--color-accent);
}

.form-note {
  font-size: 0.82rem;
  color: var(--color-text-muted);
  margin-top: var(--space-3);
  margin-bottom: 0;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-6) 0 var(--space-5);
  background: var(--color-bg-alt);
}

.footer-grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: 1fr;
  margin-bottom: var(--space-5);
}

@media (min-width: 760px) {
  .footer-grid {
    grid-template-columns: 1.2fr 1fr 1fr;
  }
}

.footer-brand .brand {
  margin-bottom: var(--space-2);
}

.footer-brand p {
  font-size: 0.9rem;
  max-width: 40ch;
}

.footer-col h3 {
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-2);
}

.footer-col ul {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-col a {
  text-decoration: none;
  font-size: 0.92rem;
  color: var(--color-text);
}

.footer-col a:hover {
  color: var(--color-accent);
}

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-4);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--color-text-muted);
}

/* Legal pages */
.legal-page main {
  padding: var(--space-7) 0 var(--space-8);
}

.legal-page h1 {
  font-size: clamp(1.6rem, 4vw, 2.2rem);
}

.legal-page h2 {
  font-size: 1.2rem;
  margin-top: var(--space-5);
}

.legal-page .todo {
  border: 1px dashed var(--color-accent);
  background: rgba(34, 211, 182, 0.08);
  border-radius: var(--radius-sm);
  padding: var(--space-3);
  font-size: 0.9rem;
  margin: var(--space-2) 0 var(--space-4);
}

.legal-page .todo strong {
  color: var(--color-accent);
}

.legal-page a.back-link {
  display: inline-block;
  margin-bottom: var(--space-4);
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 600;
}