:root {
  color-scheme: light;
  --bg: #eef3f8;
  --bg-strong: #ffffff;
  --panel: #ffffff;
  --text: #172033;
  --muted: #697386;
  --line: rgba(31, 55, 91, 0.12);
  --line-strong: rgba(31, 55, 91, 0.22);
  --accent: #1976f3;
  --accent-dark: #0f5fd2;
  --accent-soft: rgba(25, 118, 243, 0.12);
  --hot: #f94877;
  --hot-soft: rgba(249, 72, 119, 0.12);
  --sand: #eadfce;
  --sand-dark: #796a59;
  --shadow: 0 16px 34px rgba(24, 48, 87, 0.12);
  --radius-lg: 22px;
  --radius-md: 16px;
  --radius-sm: 11px;
  font-family: "Brigadier", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    linear-gradient(180deg, #1677f2 0 190px, var(--bg) 190px 100%);
  color: var(--text);
}

body.welcome-page {
  background: var(--bg);
}

button,
input {
  font: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

button:disabled {
  cursor: default;
  opacity: 0.48;
}

.app-shell {
  width: min(820px, 100%);
  min-height: 100vh;
  margin: 0 auto;
  padding: 18px 16px 26px;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 16px;
}

.welcome-shell {
  grid-template-rows: 1fr;
  place-items: center;
}

.screen-card,
.welcome-card,
.learn-card,
.training-card,
.finish-card,
.mode-screen,
.course-screen {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--panel);
  box-shadow: var(--shadow);
}

.welcome-card {
  max-width: 520px;
  padding: 26px;
  display: grid;
  gap: 22px;
}

.welcome-copy {
  display: grid;
  gap: 10px;
}

.app-kicker {
  margin: 0;
  color: var(--hot);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0;
}

h1,
h2,
p {
  margin: 0;
}

h1 {
  font-size: 34px;
  line-height: 1.08;
  font-weight: 800;
}

.welcome-copy p:not(.app-kicker) {
  color: var(--muted);
  font-size: 18px;
  line-height: 1.45;
}

.callsign-form {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 54px;
  gap: 12px;
  align-items: center;
}

.field-label {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.text-input {
  width: 100%;
  min-height: 54px;
  border: 2px solid var(--line);
  border-radius: 14px;
  background: #f8fbff;
  color: var(--text);
  padding: 0 16px;
  font-size: 18px;
  outline: none;
  caret-color: var(--hot);
}

.text-input:focus {
  border-color: var(--accent);
  background: #fff;
  box-shadow: 0 0 0 4px var(--accent-soft);
}

.phonetic-answer-form .text-input,
.phonetic-answer-form .text-input:focus {
  border-color: rgba(31, 55, 91, 0.14);
  background: #fff;
  box-shadow: 0 0 0 4px rgba(25, 118, 243, 0.06);
}

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 5px 2px 0;
  color: #fff;
}

.app-header > div {
  min-width: 0;
}

.app-header h1 {
  text-wrap: balance;
}

.app-header .app-kicker {
  color: rgba(255, 255, 255, 0.78);
}

.app-header.compact h1 {
  font-size: 26px;
}

.call-badge {
  flex: 0 0 auto;
  align-self: center;
  max-width: 42%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  border: 1px solid rgba(255, 255, 255, 0.34);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.16);
  color: #fff;
  padding: 8px 12px;
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
}

.call-badge.light {
  border-color: var(--line);
  background: var(--accent-soft);
  color: var(--accent);
  max-width: 34vw;
  min-width: 56px;
}

.mode-screen {
  align-self: start;
  padding: 12px;
  display: grid;
  gap: 12px;
}

.course-shell {
  grid-template-rows: 1fr;
}

.course-screen {
  align-self: start;
  padding: 18px;
  display: grid;
  gap: 18px;
}

.course-heading-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 14px;
  align-items: start;
}

.screen-heading {
  min-width: 0;
  display: grid;
  gap: 7px;
}

.screen-heading h1 {
  font-size: 30px;
  line-height: 1.1;
}

.course-list {
  display: grid;
  gap: 12px;
}

.admin-entry-button {
  width: min(220px, 100%);
  justify-self: center;
}

.admin-screen {
  align-content: start;
}

.admin-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #fff;
  padding: 16px;
  display: grid;
  gap: 12px;
}

.admin-panel h2 {
  font-size: 20px;
  line-height: 1.15;
}

.admin-list {
  display: grid;
  gap: 10px;
}

.admin-row {
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 12px;
  display: grid;
  gap: 4px;
}

.admin-row strong {
  font-size: 18px;
}

.admin-row span,
.admin-row small,
.admin-muted {
  color: var(--muted);
}

.course-card {
  width: 100%;
  min-height: 92px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #fff;
  color: var(--text);
  padding: 14px;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 14px;
  text-align: left;
  cursor: pointer;
}

.course-card:active,
.mode-card:active,
.answer-button:active,
.primary-button:active {
  transform: scale(0.99);
}

.course-pin {
  width: 42px;
  height: 42px;
  border-radius: 50% 50% 50% 10px;
  background: linear-gradient(145deg, var(--hot), #ff7a9a);
  transform: rotate(-45deg);
  position: relative;
  box-shadow: 0 8px 18px rgba(249, 72, 119, 0.24);
}

.course-pin::after {
  content: "";
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #fff;
  inset: 14px;
}

.course-letter-icon {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: linear-gradient(145deg, var(--hot), #ff7a9a);
  color: #fff;
  font-size: 25px;
  font-weight: 950;
  line-height: 1;
  box-shadow: 0 8px 18px rgba(249, 72, 119, 0.24);
}

.course-copy {
  display: grid;
  gap: 4px;
}

.course-copy strong {
  font-size: 18px;
  line-height: 1.15;
}

.course-copy small {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.3;
}

.course-arrow {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  flex: 0 0 34px;
  background: var(--accent-soft);
  color: var(--accent);
}

.course-arrow svg {
  width: 21px;
  height: 21px;
  display: block;
  overflow: visible;
  fill: none;
  stroke: currentColor;
  stroke-width: 3.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.mode-card {
  width: 100%;
  min-height: 104px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--bg-strong);
  color: var(--text);
  padding: 16px;
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 16px;
  text-align: left;
  cursor: pointer;
}

.mode-card.disabled {
  cursor: default;
  opacity: 0.48;
}

.mode-icon {
  width: 46px;
  height: 46px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--hot-soft);
  color: var(--hot);
  font-weight: 800;
}

.fire-icon {
  position: relative;
}

.fire-icon::before {
  content: "";
  width: 24px;
  height: 31px;
  border-radius: 70% 30% 68% 32% / 76% 35% 65% 24%;
  background: currentColor;
  transform: rotate(38deg);
}

.fire-icon::after {
  content: "";
  position: absolute;
  width: 10px;
  height: 16px;
  border-radius: 70% 30% 68% 32% / 76% 35% 65% 24%;
  background: rgba(255, 255, 255, 0.72);
  transform: translateY(5px) rotate(35deg);
}

.mode-card strong {
  display: block;
  font-size: 20px;
  line-height: 1.15;
}

.mode-card small {
  display: block;
  margin-top: 5px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.35;
}

.mode-back-button {
  justify-self: center;
  margin-top: 2px;
}

.learn-shell {
  grid-template-rows: auto 1fr auto;
}

.learn-card {
  min-height: 0;
  padding: 16px;
  display: grid;
  gap: 14px;
}

.training-card,
.finish-card {
  padding: 16px;
  display: grid;
  gap: 16px;
}

.finish-card {
  align-self: start;
  padding: 24px;
  min-height: 62vh;
  place-content: center;
  justify-items: center;
  text-align: center;
}

.finish-card h2 {
  font-size: 30px;
  line-height: 1.12;
}

.finish-card p:not(.app-kicker) {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.4;
}

.result-date {
  color: var(--muted);
  font-size: 15px;
  font-weight: 800;
}

.result-praise {
  max-width: 310px;
  margin: -2px auto 0;
  color: var(--text);
  font-size: 18px;
  font-weight: 850;
}

.learn-title-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.card-counter {
  margin-bottom: 5px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 700;
}

.learn-title-row h2 {
  font-size: 28px;
  line-height: 1.12;
}

.definition-button {
  flex: 0 0 auto;
  width: 30px;
  height: 30px;
  border: 1px solid rgba(100, 116, 139, 0.24);
  border-radius: 50%;
  background: rgba(241, 245, 249, 0.9);
  color: #7b8794;
  font-size: 17px;
  font-weight: 900;
}

.phonetic-info-button {
  font-family: "Brigadier", sans-serif;
  font-style: italic;
  animation: infoButtonSpin 0.72s ease-out 0.18s both;
}

.definition-overlay {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgba(18, 29, 43, 0.26);
  backdrop-filter: blur(4px);
  animation: overlayFade 0.18s ease-out both;
}

.timed-choice-overlay {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgba(18, 29, 43, 0.26);
  backdrop-filter: blur(4px);
  animation: overlayFade 0.18s ease-out both;
}

.timed-choice-popover {
  width: min(360px, 100%);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 24px 60px rgba(31, 55, 91, 0.22);
  padding: 20px;
  text-align: center;
}

.timed-choice-popover strong {
  display: block;
  margin-bottom: 8px;
  font-size: 23px;
  line-height: 1.18;
}

.timed-choice-popover p {
  margin-bottom: 16px;
  color: var(--muted);
  font-size: 16px;
  line-height: 1.4;
}

.timed-choice-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.definition-popover {
  width: min(360px, 100%);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.96);
  box-shadow: 0 24px 60px rgba(31, 55, 91, 0.22);
  padding: 20px;
}

.definition-popover strong {
  display: block;
  margin-bottom: 8px;
  font-size: 21px;
  line-height: 1.18;
}

.definition-popover p {
  color: var(--muted);
  font-size: 16px;
  line-height: 1.45;
}

.phonetic-info-popover p {
  margin: 0;
  color: var(--text);
  font-weight: 400;
}

.study-grid {
  min-height: 0;
  display: grid;
  grid-template-columns: minmax(220px, 0.75fr) minmax(280px, 1.25fr);
  gap: 14px;
}

.single-study-grid {
  grid-template-columns: 1fr;
}

.image-panel {
  min-width: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.76);
  padding: 12px;
  display: grid;
  grid-template-rows: auto 1fr;
  gap: 10px;
}

.image-panel span {
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}

.symbol-frame,
.illustration-frame {
  border-radius: var(--radius-sm);
  background: #fff;
  display: grid;
  place-items: center;
  overflow: hidden;
}

.symbol-frame {
  min-height: 260px;
  padding: 24px;
}

.symbol-frame img {
  max-width: 100%;
  max-height: 230px;
  object-fit: contain;
  animation: imageReveal 1.2s ease-out both;
}

.illustration-frame {
  min-height: 330px;
}

.illustration-frame img {
  width: 100%;
  height: 100%;
  min-height: 330px;
  object-fit: cover;
  animation: optionSlideUp 0.9s ease-out 0.12s both;
}

.alphabet-card-frame {
  min-height: 440px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #fff;
  display: grid;
  place-items: center;
  overflow: hidden;
  animation: optionSlideUp 0.9s ease-out both;
}

.alphabet-card-frame.compact {
  min-height: 320px;
}

.alphabet-card-frame img {
  width: 100%;
  height: 100%;
  min-height: inherit;
  object-fit: contain;
}

.training-symbol-frame {
  min-height: 280px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #fff;
  display: grid;
  place-items: center;
  padding: 26px;
}

.training-symbol-frame img {
  max-width: 100%;
  max-height: 230px;
  object-fit: contain;
  animation: imageReveal 1.2s ease-out both;
}

.training-timer {
  flex: 0 0 auto;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: rgba(25, 118, 243, 0.12);
  color: var(--accent);
  display: grid;
  place-items: center;
  font-size: 20px;
  font-weight: 950;
}

.text-options,
.image-options {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.answer-button {
  position: relative;
  min-height: 68px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.92);
  color: var(--text);
  padding: 12px 14px;
  cursor: pointer;
  font-weight: 750;
  text-align: center;
  overflow: hidden;
}

.answer-button:active {
  transform: scale(0.99);
}

.image-answer {
  min-height: 150px;
  display: grid;
  place-items: center;
  animation: optionSlideUp 0.8s ease-out both;
  background: rgba(255, 255, 255, 0.92);
}

.image-answer:nth-child(2) {
  animation-delay: 0.08s;
}

.image-answer:nth-child(3) {
  animation-delay: 0.16s;
}

.image-answer:nth-child(4) {
  animation-delay: 0.24s;
}

.image-answer img {
  max-width: 100%;
  max-height: 118px;
  object-fit: contain;
}

.answer-button.correct {
  border-color: rgba(52, 199, 89, 0.7);
  background: rgba(52, 199, 89, 0.14);
  animation: answerCorrectFill 0.58s ease-out both;
}

.answer-button.wrong {
  border-color: rgba(255, 59, 48, 0.72);
  background: rgba(255, 59, 48, 0.13);
}

.answer-button.missed-correct {
  border-color: rgba(255, 59, 48, 0.82);
  background: rgba(255, 59, 48, 0.2);
  animation: timeoutAnswerPulse 0.72s ease-out both;
}

.training-card.timeout-flash {
  animation: timeoutFlash 0.72s ease-out both;
}

.training-result {
  min-height: 24px;
  color: var(--muted);
  font-weight: 800;
}

.training-result.correct {
  color: #248a3d;
}

.training-result.wrong {
  color: #d70015;
}

.phonetic-training-card {
  position: relative;
}

.phonetic-answer-form {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 54px;
  gap: 10px;
  align-items: center;
}

.submit-arrow-button {
  width: 54px;
  height: 54px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: var(--accent);
  color: #fff;
  cursor: pointer;
  transition: transform 140ms ease, background 140ms ease, opacity 140ms ease;
}

.submit-arrow-button svg {
  width: 25px;
  height: 25px;
  display: block;
  fill: none;
  stroke: currentColor;
  stroke-width: 3.6;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.submit-arrow-button:active {
  transform: scale(0.94);
  background: var(--accent-dark);
}

.submit-arrow-button:disabled {
  opacity: 0.45;
  cursor: default;
}

.letter-prompt {
  min-height: 240px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #fff;
  display: grid;
  place-items: center;
  color: var(--accent);
  font-size: 112px;
  font-weight: 950;
  animation: optionSlideUp 0.9s ease-out both;
}

.phonetic-feedback {
  position: absolute;
  inset: 0;
  z-index: 5;
  display: grid;
  place-items: center;
  border-radius: inherit;
  color: #fff;
  font-size: 48px;
  font-weight: 950;
  pointer-events: none;
  animation: correctBurst 0.79s ease-out forwards;
}

.phonetic-feedback.correct {
  background: rgba(52, 199, 89, 0.62);
}

.phonetic-feedback.wrong {
  background: rgba(255, 59, 48, 0.62);
}

.answer-burst {
  position: absolute;
  inset: 0;
  z-index: 2;
  display: grid;
  place-items: center;
  border-radius: inherit;
  background: rgba(52, 199, 89, 0.62);
  color: #fff;
  font-size: 28px;
  font-weight: 900;
  pointer-events: none;
  animation: correctBurst 0.79s ease-out forwards;
}

.answer-burst.inline {
  font-size: 24px;
}

.result-chart {
  position: relative;
  width: 190px;
  aspect-ratio: 1;
  border-radius: 50%;
  background: conic-gradient(#34c759 0 var(--correct-percent), #ffb3c1 var(--correct-percent) 100%);
  display: grid;
  place-items: center;
  box-shadow: inset 0 0 0 1px var(--line);
  animation: resultSpin 1.7s cubic-bezier(0.1, 0.82, 0.18, 1) both;
}

.result-chart::before {
  content: "";
  width: 116px;
  aspect-ratio: 1;
  border-radius: 50%;
  background: var(--bg-strong);
  box-shadow: 0 0 0 1px var(--line);
}

.result-chart span {
  position: absolute;
  font-size: 26px;
  font-weight: 850;
}

.chart-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 16px;
  color: var(--muted);
  font-size: 15px;
  font-weight: 700;
}

.chart-legend span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.legend-dot {
  width: 11px;
  height: 11px;
  border-radius: 50%;
}

.correct-dot {
  background: #34c759;
}

.wrong-dot {
  background: #ffb3c1;
}

@keyframes imageReveal {
  from {
    filter: blur(18px);
    opacity: 0.55;
    transform: scale(1.025);
  }

  to {
    filter: blur(0);
    opacity: 1;
    transform: scale(1);
  }
}

@keyframes optionSlideUp {
  from {
    opacity: 0;
    transform: translateY(34px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes correctBurst {
  0% {
    opacity: 0;
    filter: blur(0);
    transform: scale(0.7);
  }

  22% {
    opacity: 1;
    filter: blur(0);
    transform: scale(1);
  }

  100% {
    opacity: 0;
    filter: blur(12px);
    transform: scale(1.75);
  }
}

.phonetic-card-prompt {
  color: var(--accent);
  font-size: 62px;
  font-weight: 950;
  line-height: 1;
  text-align: center;
  animation: optionSlideUp 0.6s ease-out both;
}

@keyframes timeoutFlash {
  0%,
  100% {
    background: rgba(255, 255, 255, 0.86);
  }

  28%,
  62% {
    background: rgba(255, 59, 48, 0.2);
  }
}

@keyframes timeoutAnswerPulse {
  0%,
  100% {
    box-shadow: 0 0 0 rgba(255, 59, 48, 0);
  }

  35%,
  70% {
    box-shadow: 0 0 0 8px rgba(255, 59, 48, 0.12);
  }
}

@keyframes overlayFade {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

@keyframes infoButtonSpin {
  from {
    transform: rotateY(0deg);
  }

  to {
    transform: rotateY(360deg);
  }
}

@keyframes answerCorrectFill {
  0% {
    background: rgba(255, 255, 255, 0.92);
    box-shadow: 0 0 0 rgba(52, 199, 89, 0);
  }

  55% {
    background: rgba(52, 199, 89, 0.34);
    box-shadow: 0 0 0 8px rgba(52, 199, 89, 0.12);
  }

  100% {
    background: rgba(52, 199, 89, 0.14);
    box-shadow: 0 0 0 rgba(52, 199, 89, 0);
  }
}

@keyframes loadingDotsDrift {
  0%,
  100% {
    transform: translateX(0);
  }

  50% {
    transform: translateX(calc(var(--dot-shift) * 1px));
  }
}

@keyframes resultSpin {
  0% {
    transform: rotate(-540deg) scale(0.9);
  }

  72% {
    transform: rotate(-24deg) scale(1.02);
  }

  100% {
    transform: rotate(0) scale(1);
  }
}

@keyframes sideRevealRight {
  to {
    opacity: 0.62;
    transform: translateX(0);
  }
}

@keyframes sideRevealLeft {
  to {
    opacity: 0.62;
    transform: translateX(0);
  }
}

.loader,
.empty-state {
  min-height: 320px;
  display: grid;
  place-items: center;
  padding: 24px;
  color: var(--muted);
  text-align: center;
  line-height: 1.4;
}

.loading-shell {
  min-height: 100dvh;
  width: min(820px, 100%);
  margin: 0 auto;
  padding: 24px;
  display: grid;
  place-items: center;
}

.loading-screen {
  display: grid;
  place-items: center;
}

.loading-dots {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 2px;
  color: var(--text);
  font-size: 32px;
  font-weight: 950;
  line-height: 1;
}

.loading-dots span {
  display: inline-block;
  will-change: transform;
  animation: loadingDotsDrift 1.4s ease-in-out infinite;
}

.loading-dots span:nth-child(1) {
  --dot-shift: -16;
}

.loading-dots span:nth-child(2) {
  --dot-shift: 0;
}

.loading-dots span:nth-child(3) {
  --dot-shift: 16;
}

.bottom-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.training-actions {
  display: flex;
  justify-content: center;
  align-items: center;
}

.finish-button {
  min-height: 48px;
  border: 0;
  border-radius: 999px;
  padding: 0 22px;
  background: var(--sand);
  color: var(--sand-dark);
  cursor: pointer;
  font-weight: 850;
}

.finish-button:active {
  transform: scale(0.99);
}

.side-button,
.next-side-button {
  position: fixed;
  top: 46%;
  z-index: 8;
  width: 58px;
  height: 118px;
  border: 1px solid rgba(25, 118, 243, 0.16);
  background: rgba(197, 226, 255, 0.46);
  color: var(--accent);
  cursor: pointer;
  font-size: 34px;
  font-weight: 950;
  box-shadow: 0 12px 28px rgba(24, 48, 87, 0.12);
  backdrop-filter: blur(12px);
  opacity: 0;
}

.next-side-button,
.side-button-right {
  right: 0;
  border-right: 0;
  border-radius: 30px 0 0 30px;
  transform: translateX(64px);
  animation: sideRevealRight 0.5s ease-out 1.8s forwards;
}

.side-button-left {
  left: 0;
  border-left: 0;
  border-radius: 0 30px 30px 0;
  transform: translateX(-64px);
  animation: sideRevealLeft 0.5s ease-out 1.8s forwards;
}

.next-side-button:disabled {
  color: rgba(25, 118, 243, 0.45);
}

.next-side-button.ready {
  animation-delay: 0s;
}

.next-side-button:active,
.side-button-right:active {
  transform: translateX(2px);
}

.side-button-left:active {
  transform: translateX(-2px);
}

.pager-actions {
  display: flex;
  gap: 10px;
}

.primary-button,
.secondary-button {
  min-height: 50px;
  border-radius: 999px;
  padding: 0 18px;
  cursor: pointer;
  font-weight: 800;
}

.primary-button {
  border: 0;
  background: var(--accent);
  color: #fff;
}

.callsign-form .primary-button {
  font-weight: 400;
}

@font-face {
  font-family: "Brigadier";
  src: url("./fonts/Brigadier-Regular.otf") format("opentype");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}

@font-face {
  font-family: "Brigadier";
  src: url("./fonts/Brigadier-Italic.otf") format("opentype");
  font-style: italic;
  font-weight: 400;
  font-display: swap;
}

@font-face {
  font-family: "Brigadier";
  src: url("./fonts/Brigadier-Bold.otf") format("opentype");
  font-style: normal;
  font-weight: 700;
  font-display: swap;
}

.primary-button:active {
  background: var(--accent-dark);
}

.secondary-button {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.78);
  color: var(--text);
}

.icon-button {
  width: 54px;
  padding: 0;
  font-size: 22px;
}

@media (max-width: 680px) {
  .app-shell {
    padding: 14px 12px 18px;
  }

  h1 {
    font-size: 30px;
  }

  .app-header.compact h1 {
    font-size: 22px;
  }

  .welcome-card {
    padding: 22px;
  }

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

  .text-options,
  .image-options {
    grid-template-columns: 1fr;
  }

  .learn-title-row h2 {
    font-size: 23px;
  }

  .symbol-frame {
    min-height: 190px;
  }

  .symbol-frame img {
    max-height: 165px;
  }

  .illustration-frame,
  .illustration-frame img {
    min-height: 240px;
  }

  .alphabet-card-frame {
    min-height: 300px;
  }

  .alphabet-card-frame.compact {
    min-height: 240px;
  }

  .letter-prompt {
    min-height: 200px;
    font-size: 92px;
  }

  .training-symbol-frame {
    min-height: 210px;
  }

  .training-symbol-frame img {
    max-height: 170px;
  }

  .finish-card h2 {
    font-size: 24px;
  }

  .result-chart {
    width: 160px;
  }

  .result-chart::before {
    width: 98px;
  }
}

.welcome-shell.callsign-welcome-shell {
  place-items: start center;
  padding-top: 210px;
}

.welcome-content {
  width: 100%;
  display: grid;
  justify-items: center;
  gap: 18px;
  transform: translateY(-10vh);
}

.welcome-logo {
  display: block;
  width: min(310px, 76vw);
  height: auto;
  object-fit: contain;
  will-change: transform, opacity;
  animation: welcomeLogoEnter 3s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

.callsign-welcome-shell .welcome-card {
  will-change: transform, opacity;
  animation: welcomeCardEnter 3s cubic-bezier(0.22, 0.61, 0.36, 1) both;
}

@keyframes welcomeLogoEnter {
  from {
    opacity: 0;
    transform: translateY(-180px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes welcomeCardEnter {
  from {
    opacity: 0;
    transform: translateY(180px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}