* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  min-height: 100svh;
  display: grid;
  place-items: center;
  background: #0f1220;
  color: #e7e9ff;
  padding: 24px;
}


section.palidrome {
  width: min(720px, 96vw);
  background: #171a2b;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 16px;
  padding: 24px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  text-align: center;
}

h1 {
  margin: 0 0 16px;
  font-size: clamp(22px, 3.6vw, 30px);
}

.flex {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
}

.vstup,
.vysvetleni {
  width: 100%;
}

.vstup {
  display: flex;
  flex-direction: column;
  gap: 10px;
  align-items: center;
}

.vstup label {
  display: block;
  margin-bottom: 2px;
  color: #cdd3ff;
}

#text-input {
  display: block;
  width: 100%;
  max-width: 680px;
  margin-inline: auto;
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: #121528;
  color: #e7e9ff;
  text-align: center;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}
#text-input::placeholder {
  text-align: center;
  opacity: 0.7;
}
#text-input:focus-visible {
  border-color: #6c8eff;
  box-shadow: 0 0 0 4px rgba(108, 142, 255, 0.18);
}

#check-btn {
  display: inline-block;
  align-self: center;
  margin-top: 10px;
  padding: 12px 16px;
  border: 0;
  border-radius: 12px;
  cursor: pointer;
  font-weight: 600;
  color: #0b1022;
  background: linear-gradient(135deg, #6c8eff, #3de0c2);
  transition: filter 0.15s, transform 0.1s;
}

#result {
  margin-top: 12px;
  font-size: 16px;
  color: #e7e9ff;
  text-align: center;
  min-height: 1.5em;
}
#result.good { color: #3de0c2; }
#result.bad  { color: #ff6b6b; }

.vysvetleni p {
  margin: 0;
  color: #a5abcf;
  line-height: 1.5;
  text-align: center;
}


section.history {
  width: min(720px, 96vw);
  margin: 16px auto 0;
  text-align: center;
}

.arrayHistory {
  background: #171a2b;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 16px;
  
  padding: 24px 88px 24px 24px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  text-align: center;
  position: relative;
}

.arrayHistory h2 {
  margin: 0 0 12px;
  font-size: clamp(22px, 3vw, 28px);
}


#history-list {
  list-style: decimal inside;
  padding-left: 0;
  margin: 0;
  display: grid;
  gap: 10px;
  justify-items: stretch;
  color: #e7e9ff;
}


#history-list:empty::before {
  content: "No history yet";
  color: #a5abcf;
  display: block;
  padding: 12px 0;
}

#history-list li {
  background: #14172a;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 12px;
  padding: 10px 40px 10px 14px; 
  transition: border-color 0.2s, box-shadow 0.2s, transform 0.1s;
  text-align: center;
  position: relative;
}

#history-list li:hover {
  border-color: #6c8eff;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.35);
  transform: translateY(-1px);
}


#history-list li .delete {
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  width: 28px;
  height: 28px;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: #121528;
  color: #e7e9ff;
  cursor: pointer;
  line-height: 1;
  display: inline-grid;
  place-items: center;
  transition: border-color 0.2s, color 0.2s, transform 0.1s;
}
#history-list li .delete:hover {
  border-color: #ff6b6b;
  color: #ff6b6b;
}
#history-list li .delete:active {
  transform: translateY(-50%) scale(0.98);
}
#history-list li .delete:focus-visible {
  outline: 2px solid #6c8eff;
  outline-offset: 2px;
}


#clearHistory {
  position: absolute;
  top: 1rem;
  right: 1rem;
  padding: 0.35rem 0.75rem;
  font-size: 0.9rem;
  border: 1px solid black;
  border-radius: 8px;
  background: rgba(108, 142, 255, 0.14);
  cursor: pointer;
}
#clearHistory:hover { background: #eee; }


@media (max-width: 380px) {
  section.palidrome { padding: 16px; }
  #text-input, #check-btn { font-size: 14px; }
}

@media (min-width: 600px) {
  section.palidrome { padding: 28px; }
  #text-input { max-width: 720px; }
  h1 { font-size: clamp(24px, 3.2vw, 32px); }
}