/* ==========================================================================
   IT-Beratung Andreas Hähnel — Stylesheet
   ========================================================================== */

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

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color .25s ease, color .25s ease;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

img, svg { max-width: 100%; display: block; height: auto; }
a { color: var(--color-accent); text-decoration: none; transition: color .15s ease; }
a:hover { color: var(--color-accent-hover); }

h1, h2, h3, h4 { line-height: 1.2; font-weight: 700; letter-spacing: -0.02em; color: var(--color-heading); }
h1 { font-size: clamp(2rem, 5vw, 3.25rem); }
h2 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); margin-bottom: 1rem; }
h3 { font-size: 1.25rem; margin-bottom: .5rem; }

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

/* Theme Variables -----------------------------------------------------------*/
:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f5f7fb;
  --color-surface: #ffffff;
  --color-border: #e4e8ef;
  --color-text: #1f2937;
  --color-text-muted: #5b6472;
  --color-heading: #0d1b2a;
  --color-accent: #1974f9;
  --color-accent-hover: #1558c7;
  --color-accent-soft: rgba(25, 116, 249, 0.08);
  --color-cyan: #28c9fb;
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 4px 16px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 12px 32px rgba(15, 23, 42, 0.12);
  --radius: 12px;
  --radius-lg: 20px;
  --content-max: 1120px;
}

[data-theme="dark"] {
  --color-bg: #0b1220;
  --color-bg-alt: #111a2e;
  --color-surface: #16203a;
  --color-border: #25304a;
  --color-text: #d7deea;
  --color-text-muted: #9aa5b8;
  --color-heading: #ffffff;
  --color-accent: #3e8dff;
  --color-accent-hover: #6aa5ff;
  --color-accent-soft: rgba(62, 141, 255, 0.12);
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-bg: #0b1220;
    --color-bg-alt: #111a2e;
    --color-surface: #16203a;
    --color-border: #25304a;
    --color-text: #d7deea;
    --color-text-muted: #9aa5b8;
    --color-heading: #ffffff;
    --color-accent: #3e8dff;
    --color-accent-hover: #6aa5ff;
    --color-accent-soft: rgba(62, 141, 255, 0.12);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.5);
  }
}

/* Layout Primitives ---------------------------------------------------------*/
.container {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

section { padding: 4rem 0; }
@media (min-width: 768px) { section { padding: 5.5rem 0; } }

.section-head { text-align: center; margin-bottom: 3rem; }
.section-head p { color: var(--color-text-muted); max-width: 44rem; margin: 0 auto; }

.eyebrow {
  display: inline-block;
  color: var(--color-accent);
  font-weight: 600;
  font-size: .875rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  margin-bottom: .75rem;
}

/* Header --------------------------------------------------------------------*/
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--color-bg) 90%, transparent);
  backdrop-filter: saturate(160%) blur(12px);
  -webkit-backdrop-filter: saturate(160%) blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: .75rem;
  padding-bottom: .75rem;
}

.brand { display: flex; align-items: center; gap: .75rem; }
.brand img,
.hero-logo { transition: filter .25s ease; }
.brand img { height: 28px; width: auto; }

/* Logo SVG uses white text + blue mark → invert for light mode so it stays readable */
[data-theme="light"] .brand img,
[data-theme="light"] .hero-logo { filter: invert(1) hue-rotate(180deg); }
@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) .brand img,
  :root:not([data-theme="dark"]) .hero-logo { filter: invert(1) hue-rotate(180deg); }
}

.nav {
  display: flex;
  align-items: center;
  gap: .5rem;
}

.nav a.nav-link {
  color: var(--color-text);
  font-weight: 500;
  padding: .5rem .75rem;
  border-radius: 8px;
}
.nav a.nav-link:hover { background: var(--color-accent-soft); color: var(--color-accent); }

@media (max-width: 720px) {
  .nav a.nav-link { display: none; }
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--color-border);
  border-radius: 10px;
  background: var(--color-surface);
  color: var(--color-text);
  cursor: pointer;
  transition: all .15s ease;
}
.icon-btn:hover { color: var(--color-accent); border-color: var(--color-accent); }
.icon-btn svg { width: 18px; height: 18px; }

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: .25rem;
  padding: .25rem;
  border: 1px solid var(--color-border);
  border-radius: 10px;
  background: var(--color-surface);
}
.lang-switch a {
  padding: .3rem .6rem;
  border-radius: 7px;
  font-size: .875rem;
  font-weight: 600;
  color: var(--color-text-muted);
}
.lang-switch a.active { background: var(--color-accent); color: #fff; }
.lang-switch a:not(.active):hover { color: var(--color-accent); }

/* Hero ----------------------------------------------------------------------*/
.hero {
  padding: 5rem 0 4rem;
  background:
    radial-gradient(circle at 15% 10%, var(--color-accent-soft), transparent 45%),
    radial-gradient(circle at 85% 85%, color-mix(in srgb, var(--color-cyan) 15%, transparent), transparent 50%);
}
@media (min-width: 768px) { .hero { padding: 7rem 0 5rem; } }

.hero h1 { margin-bottom: 1rem; }
.hero .subtitle {
  font-size: clamp(1.05rem, 2vw, 1.2rem);
  color: var(--color-text-muted);
  max-width: 40rem;
  margin-bottom: 2rem;
}

.hero-logo {
  max-width: 360px;
  margin-bottom: 2rem;
}

.cta-group {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: .5rem;
  padding: .75rem 1.25rem;
  border-radius: 10px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
  font-size: 1rem;
  transition: all .15s ease;
  text-decoration: none;
}
.btn-primary { background: var(--color-accent); color: #fff; }
.btn-primary:hover { background: var(--color-accent-hover); color: #fff; }
.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}
.btn-secondary:hover { border-color: var(--color-accent); color: var(--color-accent); }

/* Services & Cards ----------------------------------------------------------*/
.services, .portfolio, .skills, .contact, .about { position: relative; }
.about { background: var(--color-bg-alt); }
.portfolio { background: var(--color-bg-alt); }

.grid { display: grid; gap: 1.25rem; }
.grid-2 { grid-template-columns: 1fr; }
.grid-3 { grid-template-columns: 1fr; }
.grid-4 { grid-template-columns: 1fr; }

@media (min-width: 640px) {
  .grid-2 { grid-template-columns: repeat(2, 1fr); }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 960px) {
  .grid-3 { grid-template-columns: repeat(3, 1fr); }
  .grid-4 { grid-template-columns: repeat(4, 1fr); }
}

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.75rem;
  box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); border-color: color-mix(in srgb, var(--color-accent) 40%, var(--color-border)); }

.card-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: var(--color-accent-soft);
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1rem;
}
.card-icon svg { width: 22px; height: 22px; }
.card p { color: var(--color-text-muted); }

/* About ---------------------------------------------------------------------*/
.about-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: center;
}
@media (min-width: 900px) {
  .about-grid { grid-template-columns: 1fr 1fr; gap: 4rem; }
}
.about-text p { color: var(--color-text-muted); }
.about-text p + p { margin-top: 1rem; }

/* Skills --------------------------------------------------------------------*/
.skill-group {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.5rem;
}
.skill-group h3 {
  font-size: 1.05rem;
  margin-bottom: 1rem;
  color: var(--color-accent);
  display: flex;
  align-items: center;
  gap: .5rem;
}
.skill-group h3 svg { width: 18px; height: 18px; }
.skill-list { display: flex; flex-wrap: wrap; gap: .5rem; list-style: none; padding: 0; }
.skill-list li {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  padding: .3rem .75rem;
  font-size: .875rem;
  color: var(--color-text-muted);
}

/* Portfolio -----------------------------------------------------------------*/
.portfolio-card {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding: 2rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: transform .2s ease, box-shadow .2s ease;
}
.portfolio-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.portfolio-badge {
  align-self: flex-start;
  font-size: .75rem;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--color-accent);
  background: var(--color-accent-soft);
  padding: .25rem .6rem;
  border-radius: 999px;
}
.portfolio-card h3 { margin-bottom: 0; }
.portfolio-card p { color: var(--color-text-muted); }
.portfolio-card .link {
  margin-top: auto;
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  font-weight: 600;
}

/* Contact / Form ------------------------------------------------------------*/
.contact-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
}
@media (min-width: 900px) {
  .contact-grid { grid-template-columns: 1fr 1.2fr; }
}

.contact-info {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 2rem;
}
.contact-info h3 { margin-bottom: 1rem; }
.contact-info dl { margin: 0; }
.contact-info dt {
  font-size: .75rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--color-text-muted);
  margin-top: 1.1rem;
}
.contact-info dt:first-child { margin-top: 0; }
.contact-info dd { margin: .2rem 0 0; font-weight: 500; }
.contact-info dd a { color: var(--color-text); }
.contact-info dd a:hover { color: var(--color-accent); }

form.contact-form {
  display: grid;
  gap: 1rem;
}
.field { display: flex; flex-direction: column; gap: .4rem; }
.field label {
  font-size: .875rem;
  font-weight: 600;
  color: var(--color-text);
}
.field input,
.field textarea {
  font: inherit;
  padding: .75rem .9rem;
  border-radius: 10px;
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  color: var(--color-text);
  transition: border-color .15s ease, box-shadow .15s ease;
  width: 100%;
}
.field textarea { resize: vertical; min-height: 140px; }
.field input:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-accent-soft);
}
.row-2 {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}
@media (min-width: 640px) { .row-2 { grid-template-columns: 1fr 1fr; } }

.consent {
  display: flex;
  gap: .6rem;
  align-items: flex-start;
  font-size: .875rem;
  color: var(--color-text-muted);
}
.consent input { margin-top: .2rem; width: auto; }

.form-status {
  padding: .75rem 1rem;
  border-radius: 10px;
  font-size: .9rem;
  display: none;
}
.form-status.success {
  display: block;
  background: rgba(34, 197, 94, 0.12);
  color: #16a34a;
  border: 1px solid rgba(34, 197, 94, 0.3);
}
.form-status.error {
  display: block;
  background: rgba(239, 68, 68, 0.12);
  color: #dc2626;
  border: 1px solid rgba(239, 68, 68, 0.3);
}

/* Footer --------------------------------------------------------------------*/
.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--color-border);
  background: var(--color-bg-alt);
  padding: 2.5rem 0;
  color: var(--color-text-muted);
  font-size: .9rem;
}
.footer-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem 2rem;
  align-items: center;
  justify-content: space-between;
}
.footer-grid ul {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  list-style: none;
  padding: 0;
  margin: 0;
}
.footer-grid a { color: var(--color-text-muted); }
.footer-grid a:hover { color: var(--color-accent); }
.social {
  display: flex;
  gap: .5rem;
  list-style: none;
  padding: 0;
  margin: 0;
}
.social a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
}
.social a:hover { border-color: var(--color-accent); }
.social svg { width: 16px; height: 16px; }

/* Legal pages (Impressum / Datenschutz) -------------------------------------*/
.legal { padding-top: 3rem; padding-bottom: 4rem; }
.legal .container { max-width: 760px; }
.legal h1 { margin-bottom: 1.5rem; }
.legal h2 { margin-top: 2.5rem; font-size: 1.35rem; }
.legal h3 { margin-top: 1.5rem; font-size: 1.1rem; }
.legal p, .legal li { color: var(--color-text); }
.legal ul { padding-left: 1.25rem; margin-bottom: 1rem; }
.legal ul li { margin-bottom: .25rem; }
.legal address { font-style: normal; }

/* Visually hidden -----------------------------------------------------------*/
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0);
  white-space: nowrap; border: 0;
}

/* Reduce motion -------------------------------------------------------------*/
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
}