/* =========================================================
   GRUNDEINSTELLUNGEN
   ========================================================= */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: Arial, Helvetica, sans-serif;
  color: #f4f0ff;
  background:
    radial-gradient(
      circle at 70% 10%,
      rgba(116, 55, 214, 0.25),
      transparent 30%
    ),
    radial-gradient(
      circle at 20% 70%,
      rgba(73, 39, 150, 0.18),
      transparent 30%
    ),
    #090611;

  min-height: 100vh;
  overflow-x: hidden;
}

/* =========================================================
   STERNE
   ========================================================= */

.stars {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;

  background-image:
    radial-gradient(circle, rgba(255, 255, 255, 0.8) 1px, transparent 1px),
    radial-gradient(circle, rgba(180, 150, 255, 0.5) 1px, transparent 1px);

  background-size:
    120px 120px,
    200px 200px;
  background-position:
    20px 30px,
    80px 100px;

  opacity: 0.25;
}

/* =========================================================
   NAVIGATION
   ========================================================= */

.navbar {
  width: 100%;
  height: 80px;

  display: flex;
  align-items: center;
  justify-content: space-between;

  padding: 0 7%;

  border-bottom: 1px solid rgba(255, 255, 255, 0.07);

  background: rgba(9, 6, 17, 0.65);
  backdrop-filter: blur(15px);

  position: relative;
  z-index: 10;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;

  font-size: 21px;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.logo-symbol {
  color: #a878ff;
  font-size: 25px;
}

.logo-accent {
  color: #a878ff;
}

.navbar nav {
  display: flex;
  gap: 35px;
}

.navbar nav a {
  color: #bdb6cc;
  text-decoration: none;
  font-size: 14px;

  transition: color 0.25s ease;
}

.navbar nav a:hover {
  color: #ffffff;
}

/* =========================================================
   HERO
   ========================================================= */

.hero {
  min-height: calc(100vh - 80px);

  max-width: 1200px;
  margin: auto;

  padding: 100px 7%;

  display: flex;
  align-items: center;
  justify-content: space-between;

  position: relative;
}

.hero-content {
  max-width: 650px;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 10px;

  color: #a878ff;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;

  margin-bottom: 25px;
}

.eyebrow span {
  width: 7px;
  height: 7px;

  border-radius: 50%;
  background: #a878ff;

  box-shadow: 0 0 12px #a878ff;
}

.hero h1 {
  font-size: clamp(55px, 7vw, 92px);
  line-height: 0.95;

  letter-spacing: -4px;

  margin-bottom: 30px;
}

.hero h1 span {
  color: #a878ff;

  text-shadow: 0 0 25px rgba(168, 120, 255, 0.3);
}

.hero p {
  max-width: 530px;

  color: #aaa3b8;
  font-size: 17px;
  line-height: 1.7;

  margin-bottom: 35px;
}

.hero-button {
  display: inline-flex;
  align-items: center;
  gap: 30px;

  padding: 15px 20px 15px 25px;

  color: white;
  text-decoration: none;

  background: linear-gradient(135deg, #8050d8, #5d35a7);

  border: 1px solid rgba(190, 150, 255, 0.4);
  border-radius: 8px;

  font-size: 14px;
  font-weight: 600;

  box-shadow: 0 10px 30px rgba(93, 53, 167, 0.3);

  transition: all 0.25s ease;
}

.hero-button span {
  font-size: 18px;
}

.hero-button:hover {
  transform: translateY(-3px);

  box-shadow: 0 15px 40px rgba(128, 80, 216, 0.4);
}

/* =========================================================
   PLANET
   ========================================================= */

.hero-orbit {
  width: 330px;
  height: 330px;

  display: flex;
  align-items: center;
  justify-content: center;

  position: relative;
}

.planet {
  width: 190px;
  height: 190px;

  border-radius: 50%;

  background: radial-gradient(
    circle at 35% 30%,
    #c69cff,
    #8dd045 45%,
    #351c64 75%,
    #150b29
  );

  box-shadow:
    0 0 40px rgba(139, 83, 230, 0.5),
    0 0 100px rgba(91, 45, 160, 0.25);

  position: relative;
}

.planet::after {
  content: "";

  position: absolute;
  width: 40px;
  height: 25px;

  top: 50px;
  left: 35px;

  background: rgba(35, 15, 60, 0.3);

  border-radius: 50%;
  transform: rotate(-20deg);
}

.planet-ring {
  position: absolute;

  width: 310px;
  height: 90px;

  border: 2px solid rgba(187, 145, 255, 0.35);
  border-radius: 50%;

  transform: rotate(-20deg);
}

/* =========================================================
   ALLGEMEINE SECTIONS
   ========================================================= */

.subjects {
  max-width: 1200px;
  margin: auto;

  padding: 100px 7%;
}

.section-heading {
  display: flex;
  gap: 25px;
  align-items: flex-start;

  margin-bottom: 70px;
}

.section-number {
  color: #8050d8;

  font-family: monospace;
  font-size: 14px;
}

.section-label {
  color: #8f879f;

  font-size: 11px;
  font-weight: 700;

  letter-spacing: 2px;

  margin-bottom: 10px;
}

.section-heading h2 {
  font-size: clamp(30px, 4vw, 48px);

  letter-spacing: -1.5px;
}

/* =========================================================
   FACHBEREICHE
   ========================================================= */

.subject-category {
  margin-bottom: 80px;
}

.category-title {
  display: flex;
  align-items: center;
  gap: 18px;

  margin-bottom: 25px;
}

.category-icon {
  width: 50px;
  height: 50px;

  display: flex;
  align-items: center;
  justify-content: center;

  border-radius: 12px;

  font-size: 23px;
}

.chemistry-icon {
  color: #c29aff;

  background: rgba(133, 76, 216, 0.15);

  border: 1px solid rgba(165, 111, 255, 0.2);
}

.engineering-icon {
  color: #bba2ff;

  background: rgba(104, 78, 180, 0.15);

  border: 1px solid rgba(150, 120, 220, 0.2);
}

.category-title h3 {
  font-size: 22px;
  margin-bottom: 4px;
}

.category-title p {
  color: #80798c;
  font-size: 13px;
}

/* =========================================================
   KURS-BUTTONS
   ========================================================= */

.course-grid {
  display: grid;

  grid-template-columns: repeat(4, 1fr);

  gap: 15px;
}

.course-card {
  min-height: 150px;

  padding: 25px;

  display: flex;
  flex-direction: column;
  justify-content: space-between;

  color: white;
  text-decoration: none;

  background: linear-gradient(
    145deg,
    rgba(35, 25, 52, 0.9),
    rgba(20, 14, 30, 0.9)
  );

  border: 1px solid rgba(255, 255, 255, 0.08);

  border-radius: 12px;

  position: relative;
  overflow: hidden;

  transition:
    transform 0.25s ease,
    border-color 0.25s ease,
    background 0.25s ease;
}

.course-card::before {
  content: "";

  position: absolute;

  width: 100px;
  height: 100px;

  right: -50px;
  top: -50px;

  background: #8d52e8;

  filter: blur(60px);

  opacity: 0;

  transition: opacity 0.3s ease;
}

.course-card:hover {
  transform: translateY(-6px);

  border-color: rgba(168, 120, 255, 0.5);

  background: linear-gradient(
    145deg,
    rgba(48, 31, 72, 0.95),
    rgba(24, 16, 36, 0.95)
  );

  box-shadow: 0 15px 40px rgba(0, 0, 0, 0.25);
}

.course-card:hover::before {
  opacity: 0.5;
}

.course-code {
  color: #7f748f;

  font-size: 10px;
  font-weight: 700;

  letter-spacing: 1.5px;
}

.course-card strong {
  font-size: 24px;
  font-weight: 600;

  position: relative;
}

.course-arrow {
  align-self: flex-end;

  color: #9c6dea;
  font-size: 20px;

  position: relative;
}

/* =========================================================
   ÜBER UNS
   ========================================================= */

.about {
  max-width: 1200px;
  margin: auto;

  padding: 40px 7% 120px;
}

.about-card {
  padding: 70px;

  border-radius: 18px;

  background:
    radial-gradient(
      circle at 80% 20%,
      rgba(124, 71, 211, 0.2),
      transparent 35%
    ),
    rgba(24, 16, 35, 0.8);

  border: 1px solid rgba(255, 255, 255, 0.07);
}

.about-card h2 {
  font-size: clamp(35px, 5vw, 60px);

  line-height: 1;

  letter-spacing: -2px;

  margin-bottom: 25px;
}

.about-card h2 span {
  color: #a878ff;
}

.about-card p {
  max-width: 600px;

  color: #aaa3b8;

  line-height: 1.7;
}

/* =========================================================
   FOOTER
   ========================================================= */

footer {
  padding: 35px 7%;

  border-top: 1px solid rgba(255, 255, 255, 0.07);

  display: flex;
  align-items: center;
  justify-content: space-between;

  color: #71697d;

  font-size: 12px;
}

.footer-logo {
  color: white;
  font-weight: 700;
}

.footer-logo:first-letter {
  color: #a878ff;
}

.footer-logo span {
  color: #a878ff;
}

/* =========================================================
   RESPONSIVE DESIGN – TABLET
   ========================================================= */

@media (max-width: 900px) {
  .hero {
    padding-top: 70px;
  }

  .hero-orbit {
    width: 230px;
    height: 230px;
  }

  .planet {
    width: 140px;
    height: 140px;
  }

  .planet-ring {
    width: 220px;
    height: 70px;
  }

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

/* =========================================================
   RESPONSIVE DESIGN – HANDY
   ========================================================= */

@media (max-width: 650px) {
  .navbar {
    height: 70px;
    padding: 0 6%;
  }

  .navbar nav {
    display: none;
  }

  .hero {
    min-height: auto;

    padding: 80px 6% 100px;

    display: block;
  }

  .hero h1 {
    font-size: 58px;
    letter-spacing: -3px;
  }

  .hero p {
    font-size: 15px;
  }

  .hero-orbit {
    display: none;
  }

  .subjects {
    padding: 70px 6%;
  }

  .section-heading {
    margin-bottom: 50px;
  }

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

  .course-card {
    min-height: 125px;
  }

  .about {
    padding: 20px 6% 80px;
  }

  .about-card {
    padding: 40px 30px;
  }

  footer {
    padding: 30px 6%;

    flex-direction: column;
    gap: 15px;

    align-items: flex-start;
  }
}