:root {
  --bg: 6 10 8;
  --panel: 11 16 13;
  --green: 74 222 128;
  --green-dim: 74 222 128;
  --red: 248 90 90;
  --amber: 245 179 60;
  --text: 190 210 195;

  --ease-out-quad: cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

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

body {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  background: rgb(var(--bg));
  color: rgb(var(--text));
  font-family: 'IBM Plex Mono', ui-monospace, SFMono-Regular, monospace;
}

/* Sutil textura CRT: líneas horizontales muy tenues, no distraen. */
.crt {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 0;
  background: repeating-linear-gradient(
    0deg,
    rgb(255 255 255 / 0.015) 0px,
    rgb(255 255 255 / 0.015) 1px,
    transparent 1px,
    transparent 3px
  );
}

.terminal {
  position: relative;
  z-index: 1;
  width: 100%;
  max-width: 480px;
  border-radius: 10px;
  border: 1px solid rgb(var(--green) / 0.25);
  background: rgb(var(--panel));
  box-shadow:
    0 0 0 1px rgb(0 0 0 / 0.4),
    0 30px 60px -25px rgb(0 0 0 / 0.8),
    0 0 40px -12px rgb(var(--green) / 0.15);
  overflow: hidden;
}

.titlebar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 14px;
  background: rgb(0 0 0 / 0.35);
  border-bottom: 1px solid rgb(var(--green) / 0.15);
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  opacity: 0.85;
}

.dot--red {
  background: rgb(var(--red));
}
.dot--yellow {
  background: rgb(var(--amber));
}
.dot--green {
  background: rgb(var(--green));
}

.titlebar-name {
  margin-left: 6px;
  font-size: 0.75rem;
  color: rgb(var(--text) / 0.5);
}

.screen {
  padding: 1.5rem 1.25rem;
}

.line {
  font-size: 0.9rem;
  line-height: 1.8;
  margin-bottom: 0.9rem;
  color: rgb(var(--text) / 0.85);
}

.prompt {
  color: rgb(var(--green));
  font-weight: 600;
}

.caret {
  display: inline-block;
  color: rgb(var(--green));
  animation: blink 1s step-end infinite;
}

@media (prefers-reduced-motion: reduce) {
  .caret {
    animation: none;
  }
}

@keyframes blink {
  0%,
  49% {
    opacity: 1;
  }
  50%,
  100% {
    opacity: 0;
  }
}

.line--field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.input-wrapper {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  border: 1px solid rgb(var(--green) / 0.25);
  border-radius: 6px;
  background: rgb(0 0 0 / 0.35);
  padding: 0.6rem 0.75rem;
  transition: border-color 200ms ease;
}

.input-wrapper:focus-within {
  border-color: rgb(var(--green) / 0.7);
}

input {
  flex: 1;
  min-width: 0;
  background: none;
  border: none;
  outline: none;
  color: rgb(var(--text));
  font: inherit;
  letter-spacing: 0.05em;
}

input::placeholder {
  color: rgb(var(--text) / 0.3);
}

input.is-shaking {
  animation: shake 380ms var(--ease-out-quad);
}

@keyframes shake {
  0%,
  100% {
    transform: translateX(0);
  }
  20% {
    transform: translateX(-6px);
  }
  40% {
    transform: translateX(5px);
  }
  60% {
    transform: translateX(-4px);
  }
  80% {
    transform: translateX(3px);
  }
}

@media (prefers-reduced-motion: reduce) {
  input.is-shaking {
    animation: none;
  }
}

.toggle-btn {
  flex-shrink: 0;
  background: none;
  border: none;
  color: rgb(var(--text) / 0.4);
  font: inherit;
  font-size: 0.75rem;
  cursor: pointer;
  transition: color 150ms ease;
}

.toggle-btn:hover {
  color: rgb(var(--green));
}

.utility-row {
  display: flex;
  gap: 1rem;
}

.ghost-btn {
  background: none;
  border: none;
  padding: 0;
  color: rgb(var(--text) / 0.4);
  font: inherit;
  font-size: 0.78rem;
  cursor: pointer;
  transition: color 150ms ease;
}

.ghost-btn:hover {
  color: rgb(var(--green));
}

.match-hint {
  font-size: 0.78rem;
  min-height: 1.1em;
  color: rgb(var(--text) / 0.3);
  transition: color 150ms ease;
}

.match-hint.is-match {
  color: rgb(var(--green));
}

.match-hint.is-mismatch {
  color: rgb(var(--red));
}

/* ---------- Meter ---------- */
.blocks {
  letter-spacing: 1px;
  font-weight: 600;
}

.blocks .block {
  transition: color 200ms ease;
}

.blocks .block.is-filled.lvl-weak {
  color: rgb(var(--red));
}
.blocks .block.is-filled.lvl-fair {
  color: rgb(var(--amber));
}
.blocks .block.is-filled.lvl-good,
.blocks .block.is-filled.lvl-strong {
  color: rgb(var(--green));
}
.blocks .block:not(.is-filled) {
  color: rgb(var(--text) / 0.15);
}

.meter-label {
  color: rgb(var(--text) / 0.4);
  transition: color 200ms ease;
}

.meter-label.lvl-weak {
  color: rgb(var(--red));
}
.meter-label.lvl-fair {
  color: rgb(var(--amber));
}
.meter-label.lvl-good,
.meter-label.lvl-strong {
  color: rgb(var(--green));
}

/* ---------- Requirements ---------- */
.requirements {
  list-style: none;
  margin-bottom: 1.5rem;
}

.requirements li {
  font-size: 0.85rem;
  color: rgb(var(--text) / 0.4);
  margin-bottom: 0.35rem;
  transition: color 200ms ease;
}

.requirements li .box {
  display: inline-block;
  width: 3ch;
  white-space: nowrap;
  color: rgb(var(--text) / 0.3);
  transition: color 200ms ease;
}

.requirements li.is-valid {
  color: rgb(var(--green));
}

.requirements li.is-valid .box {
  color: rgb(var(--green));
}

/* ---------- Continue button ---------- */
.btn-continue {
  width: 100%;
  padding: 0.7rem;
  font: inherit;
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: rgb(var(--text) / 0.3);
  background: rgb(0 0 0 / 0.35);
  border: 1px solid rgb(var(--text) / 0.15);
  border-radius: 6px;
  cursor: pointer;
  transition:
    color 200ms ease,
    border-color 200ms ease,
    background-color 200ms ease,
    transform 150ms var(--ease-out-quad);
}

.btn-continue.is-ready {
  color: rgb(var(--bg));
  background: rgb(var(--green));
  border-color: rgb(var(--green));
}

.btn-continue:active {
  transform: scale(0.98);
}

.btn-continue.is-shaking {
  animation: shake 380ms var(--ease-out-quad);
}

.btn-continue + .btn-reset {
  margin-top: 0.75rem;
  width: 100%;
  text-align: center;
}

@media (prefers-reduced-motion: reduce) {
  .btn-continue.is-shaking {
    animation: none;
  }
}

input:disabled,
button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.line--success {
  color: rgb(var(--green));
  animation: rise-in 300ms var(--ease-out-quad) both;
}

@keyframes rise-in {
  from {
    opacity: 0;
    transform: translateY(6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  .line--success {
    animation: none;
  }
}

@media (max-width: 480px) {
  .screen {
    padding: 1.25rem 1rem;
  }
}