/* ============================================================
   STYLE.CSS – ulfvalentin.de
   Mobile-first, pure CSS, keine Frameworks
   ============================================================ */


/* ------------------------------------------------------------
   CSS CUSTOM PROPERTIES (Design Tokens)
------------------------------------------------------------ */
:root {
  --color-bg:        #ffffff;
  --color-bg-alt:    #f5f5f5;
  --color-text:      #1a1a1a;
  --color-text-muted:#666666;
  --color-accent:    #1e3a5f;
  --color-accent-light: #e8eef5;
  --color-border:    #e5e5e5;

  --font-family: 'Inter', system-ui, -apple-system, sans-serif;

  --space-xs:  0.5rem;
  --space-sm:  1rem;
  --space-md:  1.5rem;
  --space-lg:  2.5rem;
  --space-xl:  4rem;
  --space-2xl: 6rem;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,.10);

  --transition: 0.2s ease;

  --max-width: 1100px;
  --max-width-narrow: 720px;

  --header-height: 64px;
}


/* ------------------------------------------------------------
   RESET & BASE
------------------------------------------------------------ */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
  font-size: 16px;
}

body {
  font-family: var(--font-family);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: opacity var(--transition);
}

a:hover {
  opacity: 0.75;
}

ul {
  list-style: none;
}

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}


/* ------------------------------------------------------------
   LAYOUT HELPERS
------------------------------------------------------------ */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

.section-narrow {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

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

.section-alt {
  background: var(--color-bg-alt);
}


/* ------------------------------------------------------------
   TYPOGRAPHY COMPONENTS
------------------------------------------------------------ */
.section-label {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}

.section-title {
  font-size: clamp(1.5rem, 4vw, 2.25rem);
  font-weight: 700;
  line-height: 1.25;
  color: var(--color-text);
  margin-bottom: var(--space-lg);
}

.section-title.mission-headline {
  font-size: clamp(2rem, 5vw, 3rem);
  color: var(--color-accent);
}


/* ------------------------------------------------------------
   BUTTONS
------------------------------------------------------------ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: 0.875rem 1.75rem;
  border-radius: var(--radius-md);
  font-size: 0.9375rem;
  font-weight: 600;
  font-family: inherit;
  line-height: 1;
  transition: background var(--transition), color var(--transition), box-shadow var(--transition), transform var(--transition);
  cursor: pointer;
  text-decoration: none;
}

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

.btn-primary {
  background: var(--color-accent);
  color: #ffffff;
  border: 2px solid var(--color-accent);
}

.btn-primary:hover {
  background: #162e4d;
  border-color: #162e4d;
  box-shadow: var(--shadow-md);
}

.btn-outline {
  background: transparent;
  color: var(--color-accent);
  border: 2px solid var(--color-accent);
}

.btn-outline:hover {
  background: var(--color-accent-light);
}

.btn-full {
  width: 100%;
}

.btn-hero {
  background: #ffffff;
  color: var(--color-accent);
  border: 2px solid #ffffff;
  font-weight: 700;
}

.btn-hero:hover {
  background: transparent;
  color: #ffffff;
  border-color: rgba(255,255,255,0.7);
  transform: translateY(-1px);
}


/* ------------------------------------------------------------
   NAVIGATION
------------------------------------------------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.95);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
  height: var(--header-height);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.nav-logo {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
  text-decoration: none;
}

.nav-logo:hover {
  opacity: 1;
  color: var(--color-accent);
}

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

.nav-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text);
  text-decoration: none;
  transition: color var(--transition);
}

.nav-links a:hover {
  color: var(--color-accent);
  opacity: 1;
}

.nav-cta {
  background: var(--color-accent);
  color: #ffffff !important;
  padding: 0.5rem 1.125rem;
  border-radius: var(--radius-md);
  transition: background var(--transition) !important;
}

.nav-cta:hover {
  background: #162e4d !important;
  opacity: 1 !important;
}

/* Hamburger Button */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 24px;
  height: 18px;
  padding: 0;
  background: none;
  border: none;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform var(--transition), opacity var(--transition);
}


/* ------------------------------------------------------------
   HERO
------------------------------------------------------------ */
.hero {
  min-height: 88vh;
  background-image: url('Ulf Profil 2 arme.jpg');
  background-size: cover;
  background-position: center top;
  position: relative;
  display: flex;
  align-items: center;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    135deg,
    rgba(8, 18, 36, 0.84) 0%,
    rgba(8, 18, 36, 0.52) 100%
  );
}

.hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding-top: var(--space-xl);
  padding-bottom: var(--space-xl);
}

.hero-eyebrow {
  font-size: 0.8125rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.58);
  margin-bottom: var(--space-md);
}

.hero-quote {
  font-size: clamp(1.75rem, 5vw, 3.625rem);
  font-weight: 700;
  line-height: 1.18;
  color: #ffffff;
  max-width: 820px;
  margin-bottom: var(--space-md);
  letter-spacing: -0.025em;
}

.hero-sub {
  font-size: 1rem;
  color: rgba(255,255,255,0.62);
  margin-bottom: var(--space-xl);
  font-weight: 400;
}


/* ------------------------------------------------------------
   ÜBER MICH
------------------------------------------------------------ */
.bio-text p {
  font-size: 1.0625rem;
  color: var(--color-text);
  margin-bottom: var(--space-md);
}

.bio-text p:last-child {
  margin-bottom: 0;
}

.bio-text a {
  font-weight: 500;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.bio-text strong {
  font-weight: 600;
  color: var(--color-accent);
}


/* ------------------------------------------------------------
   CONVIDERA
------------------------------------------------------------ */
.convidera-intro {
  max-width: var(--max-width-narrow);
  margin-bottom: var(--space-xl);
}

.convidera-intro p {
  font-size: 1.0625rem;
  color: var(--color-text);
  margin-bottom: var(--space-md);
  line-height: 1.7;
}

.convidera-intro p:last-child {
  margin-bottom: 0;
}

.convidera-intro a {
  font-weight: 500;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.convidera-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.convidera-card {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  transition: box-shadow var(--transition), transform var(--transition);
}

.convidera-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.convidera-number {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}

.convidera-title {
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
}

.convidera-desc {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  line-height: 1.65;
}

.convidera-cta {
  text-align: center;
}


/* ------------------------------------------------------------
   MISSION
------------------------------------------------------------ */
.section-mission {
  background: var(--color-accent);
}

.section-mission .section-label {
  color: rgba(255,255,255,0.6);
}

.section-mission .section-title {
  color: #ffffff;
}

.mission-text p {
  font-size: 1.0625rem;
  color: rgba(255,255,255,0.85);
  margin-bottom: var(--space-md);
}

.mission-text p:last-child {
  margin-bottom: 0;
}


/* ------------------------------------------------------------
   THEMEN & VORTRÄGE
------------------------------------------------------------ */
.speaker-bio {
  max-width: var(--max-width-narrow);
  margin-bottom: var(--space-xl);
}

.speaker-bio p {
  font-size: 1.0625rem;
  color: var(--color-text);
  margin-bottom: var(--space-md);
}

.speaker-bio p:last-child {
  margin-bottom: 0;
}

.talks-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.talk-card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-lg);
  position: relative;
  transition: box-shadow var(--transition), transform var(--transition);
}

.talk-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.talk-number {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--color-accent);
  margin-bottom: var(--space-sm);
}

.talk-title {
  font-size: 1.125rem;
  font-weight: 700;
  line-height: 1.35;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
}

.talk-desc {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  line-height: 1.65;
  margin-top: var(--space-sm);
}

.speaker-cta {
  text-align: center;
}


/* ------------------------------------------------------------
   EVENTS
------------------------------------------------------------ */
.events-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
}

.events-subheading {
  font-size: 0.875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-muted);
  margin-bottom: var(--space-lg);
  padding-bottom: var(--space-xs);
  border-bottom: 2px solid var(--color-border);
}

.event-item {
  display: flex;
  gap: var(--space-md);
  padding-bottom: var(--space-md);
  border-bottom: 1px solid var(--color-border);
}

.event-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.event-upcoming .event-name {
  color: var(--color-accent);
}

.event-date {
  flex-shrink: 0;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-text-muted);
  min-width: 90px;
  padding-top: 2px;
}

.event-details {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.event-name {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
  line-height: 1.4;
}

.event-org,
.event-talk {
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.event-role {
  display: inline-block;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 2px 8px;
  border-radius: var(--radius-full);
  width: fit-content;
  margin-top: 4px;
}

.role-speaker {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

.role-moderator {
  background: #f0e8ff;
  color: #5b21b6;
}


/* ------------------------------------------------------------
   KONTAKT
------------------------------------------------------------ */
.contact-intro {
  font-size: 1.0625rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xl);
}

.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--color-text);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  font-family: inherit;
  font-size: 1rem;
  color: var(--color-text);
  background: var(--color-bg);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition), box-shadow var(--transition);
  appearance: none;
  -webkit-appearance: none;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(30,58,95,0.12);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: #b0b0b0;
}

.form-group textarea {
  resize: vertical;
  min-height: 140px;
}

.form-success {
  font-size: 0.9375rem;
  color: #15803d;
  min-height: 1.5em;
}

.contact-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-text);
  text-decoration: none;
  transition: color var(--transition);
}

.contact-link:hover {
  color: var(--color-accent);
  opacity: 1;
}

.contact-link svg {
  flex-shrink: 0;
  color: var(--color-accent);
}


/* ------------------------------------------------------------
   FOOTER
------------------------------------------------------------ */
.footer {
  background: var(--color-text);
  color: rgba(255,255,255,0.6);
  padding: var(--space-lg) 0;
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-md);
  text-align: center;
}

.footer-copy {
  font-size: 0.875rem;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-md);
}

.footer-links a {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.6);
  text-decoration: none;
  transition: color var(--transition);
}

.footer-links a:hover {
  color: #ffffff;
  opacity: 1;
}


/* ============================================================
   RESPONSIVE BREAKPOINTS
============================================================ */

/* ---- Tablet (640px+) ---- */
@media (min-width: 640px) {

  .talks-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .talks-grid .talk-card:last-child {
    grid-column: 1 / -1;
  }

  .convidera-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .events-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-xl);
  }

  .contact-links {
    flex-direction: row;
    flex-wrap: wrap;
    gap: var(--space-lg);
  }

  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    text-align: left;
  }
}


/* ---- Desktop (900px+) ---- */
@media (min-width: 900px) {

  .section {
    padding: var(--space-2xl) 0;
  }

  .hero {
    min-height: 90vh;
  }

  /* Talks: 3-column layout */
  .talks-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .talks-grid .talk-card:last-child {
    grid-column: auto;
  }

  /* Mobile nav hidden, desktop nav visible */
  .nav-toggle {
    display: none;
  }

  .nav-links {
    display: flex !important;
    position: static;
    flex-direction: row;
    background: none;
    border: none;
    padding: 0;
    box-shadow: none;
  }
}


/* ---- Mobile Navigation Overlay ---- */
@media (max-width: 899px) {

  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    flex-direction: column;
    align-items: flex-start;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
    padding: var(--space-md);
    gap: var(--space-md);
    box-shadow: var(--shadow-md);
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a {
    font-size: 1rem;
  }

  .nav-cta {
    width: 100%;
    text-align: center;
    padding: 0.75rem 1.125rem !important;
  }

  .nav-toggle[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }

  .nav-toggle[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }

  .site-header {
    position: sticky;
    isolation: isolate;
  }
}