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

:root {
  --color-bg: #061426;
  --color-panel: #0b1b2f;
  --color-glass: rgba(10, 24, 43, 0.82);
  --color-gold: #f1c75b;
  --color-gold-dark: #d7a941;
  --color-gold-border: rgba(241, 199, 91, 0.55);
  --color-text: #fff7e6;
  --color-muted: #cbd8e6;
  --color-teal: #14b8a6;
  --color-teal-soft: #8ee8dc;
  --color-notice-border: rgba(241, 199, 91, 0.35);
  --radius: 14px;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.42);
}

body {
  position: relative;
  min-height: 100vh;
  padding: 14px 10px 28px;
  font-family: "Apple SD Gothic Neo", "Malgun Gothic", "Segoe UI", sans-serif;
  color: var(--color-text);
  line-height: 1.4;
  background:
    radial-gradient(circle at top right, rgba(20, 184, 166, 0.16), transparent 32%),
    radial-gradient(circle at bottom left, rgba(241, 199, 91, 0.12), transparent 34%),
    linear-gradient(135deg, #061426 0%, #0b1b2f 55%, #061426 100%);
  -webkit-tap-highlight-color: transparent;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 64px 64px;
  opacity: 0.35;
}

button,
select {
  font: inherit;
}

a {
  color: inherit;
}

.site-header {
  width: min(1180px, 100%);
  margin: 0 auto 16px;
  color: var(--color-text);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 14px;
  background: rgba(8, 20, 36, 0.9);
  border: 1px solid var(--color-gold-border);
  border-radius: 22px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.site-brand {
  display: inline-flex;
  align-items: center;
  flex: 0 0 auto;
  gap: 12px;
  color: var(--color-text);
  text-decoration: none;
}

.site-brand__logo {
  width: 50px;
  height: 50px;
  border: 1px solid rgba(241, 199, 91, 0.38);
  border-radius: 14px;
  object-fit: cover;
  background: rgba(255, 255, 255, 0.06);
}

.site-brand__text {
  display: grid;
  gap: 2px;
  line-height: 1.05;
}

.site-brand__text strong {
  font-size: 0.98rem;
  letter-spacing: 0.02em;
}

.site-brand__text span {
  color: var(--color-muted);
  font-size: 0.84rem;
  font-weight: 700;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.site-nav a {
  color: rgba(255, 247, 230, 0.88);
  font-size: 0.92rem;
  font-weight: 800;
  text-decoration: none;
  transition: color 0.18s, border-color 0.18s, background 0.18s, box-shadow 0.18s, transform 0.18s;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--color-gold);
  outline: none;
}

.site-nav--main {
  flex: 1 1 260px;
  justify-content: center;
  min-width: 0;
}

.site-header__tools {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex: 1 1 560px;
  gap: 12px;
  flex-wrap: wrap;
}

.site-nav--services {
  justify-content: flex-end;
}

.site-service-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 38px;
  padding: 7px 12px;
  color: #fff5d9;
  white-space: nowrap;
  background: rgba(241, 199, 91, 0.1);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 999px;
}

.site-service-link:hover,
.site-service-link:focus-visible,
.site-service-link.is-current {
  color: #fff9e8;
  background: rgba(241, 199, 91, 0.18);
  border-color: rgba(246, 218, 145, 0.92);
  box-shadow: 0 0 20px rgba(241, 199, 91, 0.18);
  transform: translateY(-1px);
}

.language-switcher {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
  flex-wrap: wrap;
}

.lang-character-btn {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 54px;
  height: 54px;
  min-width: 54px;
  min-height: 54px;
  padding: 3px;
  overflow: hidden;
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 999px;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.24);
  text-decoration: none;
  transition: transform 0.18s, border-color 0.18s, background 0.18s, box-shadow 0.18s;
}

.lang-character-img {
  display: block;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  object-fit: contain;
  background: transparent;
}

.lang-character-btn span {
  position: absolute;
  right: 2px;
  bottom: 2px;
  min-width: 22px;
  padding: 1px 4px;
  color: #061426;
  background: var(--color-gold);
  border-radius: 999px;
  font-size: 0.58rem;
  font-weight: 900;
  line-height: 1.4;
  text-align: center;
}

.lang-character-btn:hover,
.lang-character-btn:focus-visible,
.language-switcher a.active,
.language-switcher button.active {
  background: rgba(241, 199, 91, 0.16);
  border-color: rgba(246, 218, 145, 0.92);
  box-shadow: 0 0 0 2px rgba(241, 199, 91, 0.72), 0 0 24px rgba(241, 199, 91, 0.36);
  outline: none;
  transform: translateY(-2px);
}

.guide-video-section {
  width: min(1180px, 100%);
  margin: 0 auto 16px;
  padding: 24px;
  display: grid;
  grid-template-columns: 0.95fr 1.15fr;
  gap: 24px;
  align-items: center;
  color: var(--color-text);
  background: rgba(8, 20, 36, 0.86);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 24px;
  box-shadow: 0 24px 70px rgba(0, 0, 0, 0.32);
  backdrop-filter: blur(16px);
}

.guide-video-copy {
  color: var(--color-text);
}

.section-kicker {
  margin: 0 0 8px;
  color: var(--color-gold);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.guide-video-copy h2 {
  margin: 0;
  color: var(--color-text);
  font-size: clamp(1.55rem, 3vw, 2.4rem);
  line-height: 1.15;
}

.guide-video-subtitle {
  margin: 8px 0 16px;
  color: var(--color-teal);
  font-weight: 800;
}

.guide-video-copy p {
  color: var(--color-muted);
  line-height: 1.65;
}

.guide-video-copy p + p {
  margin-top: 10px;
}

.guide-video-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 14px;
  padding: 12px 18px;
  color: #061426;
  background: linear-gradient(135deg, var(--color-gold), var(--color-gold-dark));
  border: 1px solid rgba(241, 199, 91, 0.78);
  border-radius: 999px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 12px 28px rgba(0, 0, 0, 0.2);
  font-weight: 900;
  text-decoration: none;
  transition: transform 0.18s, box-shadow 0.18s, background 0.18s;
}

.guide-video-link:hover,
.guide-video-link:focus-visible {
  background: linear-gradient(135deg, #f6d271, var(--color-gold-dark));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.24), 0 16px 34px rgba(0, 0, 0, 0.26);
  outline: none;
  transform: translateY(-1px);
}

.guide-video-frame {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: #061426;
  border: 1px solid rgba(241, 199, 91, 0.38);
  border-radius: 18px;
  box-shadow: 0 18px 50px rgba(0, 0, 0, 0.34);
}

.guide-video-frame iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

.app {
  max-width: 500px;
  margin: 0 auto;
  padding: 18px 14px 20px;
  color: var(--color-text);
  background: rgba(8, 20, 36, 0.86);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 24px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.app__header {
  text-align: center;
  margin-bottom: 12px;
  padding-bottom: 14px;
  border-bottom: 1px solid rgba(241, 199, 91, 0.26);
}

.home-link {
  display: inline-flex;
  margin-bottom: 10px;
  color: var(--color-muted);
  font-size: 0.76rem;
  font-weight: 700;
  text-decoration: none;
  transition: color 0.18s, transform 0.18s;
}

.home-link:hover {
  color: var(--color-gold);
  transform: translateY(-1px);
}

.app__eyebrow {
  margin-bottom: 6px;
  color: var(--color-gold);
  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.app__title {
  font-size: 1.45rem;
  color: var(--color-text);
  line-height: 1.2;
}

.app__subtitle {
  margin-top: 6px;
  color: var(--color-muted);
  font-size: 0.9rem;
}

.toolbar {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 8px;
}

.mode-picker,
.stage-picker {
  grid-column: 1 / -1;
  display: grid;
  gap: 5px;
  color: var(--color-muted);
  font-size: 0.8rem;
  font-weight: 700;
}

.mode-picker select,
.stage-picker select {
  min-height: 42px;
  width: 100%;
  padding: 8px 14px;
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 999px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08);
}

.mode-picker select option,
.stage-picker select option {
  color: #061426;
  background: #fff7e6;
}

.audio-status {
  min-height: 22px;
  margin: 6px 0 10px;
  color: var(--color-teal-soft);
  text-align: center;
  font-size: 0.8rem;
}

.audio-status.is-warning {
  color: var(--color-gold);
}

.status {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 12px;
}

.status__item {
  padding: 8px 4px;
  text-align: center;
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.055);
  border: 1px solid rgba(241, 199, 91, 0.28);
  border-radius: var(--radius);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06);
}

.status__label {
  display: block;
  color: var(--color-muted);
  font-size: 0.72rem;
}

.status__value {
  display: block;
  color: var(--color-gold);
  font-size: 1.05rem;
  font-weight: 800;
}

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

.card {
  position: relative;
  aspect-ratio: 1 / 1;
  border: 0;
  background: transparent;
  cursor: pointer;
  perspective: 800px;
  touch-action: manipulation;
  user-select: none;
}

.card:active {
  transform: scale(0.97);
}

.card:focus-visible {
  outline: 3px solid var(--color-gold);
  outline-offset: 2px;
  border-radius: var(--radius);
}

.card__inner {
  display: block;
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.35s;
  transform-style: preserve-3d;
}

.card.is-open .card__inner,
.card.is-matched .card__inner {
  transform: rotateY(180deg);
}

.card__face {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 8px 6px;
  text-align: center;
  border: 1px solid rgba(241, 199, 91, 0.28);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backface-visibility: hidden;
  overflow: hidden;
}

.card__back {
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background:
    radial-gradient(circle at center, rgba(241, 199, 91, 0.14), transparent 58%),
    linear-gradient(145deg, #0b1b2f 0%, #061426 100%);
  border: 1px solid rgba(241, 199, 91, 0.45);
}

.card__back::before {
  content: "";
  display: block;
  width: 78%;
  height: 78%;
  background-image: url("./assets/logo.png");
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  filter: drop-shadow(0 10px 18px rgba(0, 0, 0, 0.35));
}

.card__front {
  transform: rotateY(180deg);
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.07);
  border-color: rgba(241, 199, 91, 0.34);
}

.card__word {
  color: var(--color-text);
  font-size: clamp(0.9rem, 5.2vw, 1.45rem);
  font-weight: 900;
  line-height: 1.1;
  word-break: keep-all;
}

.card__vi {
  color: var(--color-teal-soft);
  font-size: 0.82rem;
  font-weight: 700;
  line-height: 1.2;
}

.card__en,
.card__pron {
  color: var(--color-muted);
  font-size: 0.72rem;
  line-height: 1.15;
}

.card__pron {
  color: var(--color-gold);
  font-style: italic;
}

.card.is-matched .card__front {
  border: 2px solid var(--color-teal);
  background: rgba(20, 184, 166, 0.11);
  box-shadow: 0 0 0 1px rgba(20, 184, 166, 0.35), 0 18px 40px rgba(20, 184, 166, 0.16);
}

.card.is-matched .card__front::after {
  content: "성공";
  margin-top: 2px;
  padding: 2px 9px;
  color: #061426;
  background: var(--color-teal);
  border-radius: 999px;
  font-size: 0.68rem;
  font-weight: 800;
}

.controls {
  display: flex;
  margin-top: 14px;
}

.medical-notice {
  margin-top: 12px;
  padding: 10px 12px;
  color: var(--color-text);
  background: rgba(8, 20, 36, 0.72);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 14px;
  font-size: 0.78rem;
  line-height: 1.45;
}

.btn,
.btn-mini {
  min-height: 44px;
  padding: 10px 12px;
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 999px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.08);
  font-weight: 800;
  cursor: pointer;
  touch-action: manipulation;
  transition: transform 0.18s, border-color 0.18s, background 0.18s, box-shadow 0.18s;
}

.btn {
  width: 100%;
  min-height: 50px;
  font-size: 1rem;
}

.btn--primary {
  color: #061426;
  background: linear-gradient(135deg, #f1c75b, #d7a941);
  border-color: rgba(241, 199, 91, 0.78);
}

.btn:active:not(:disabled),
.btn-mini:active:not(:disabled) {
  transform: translateY(0);
}

.btn:disabled,
.btn-mini:disabled {
  opacity: 0.48;
  cursor: not-allowed;
}

@media (hover: hover) {
  .btn:hover:not(:disabled),
  .btn-mini:hover:not(:disabled) {
    transform: translateY(-1px);
    border-color: rgba(241, 199, 91, 0.75);
    background: rgba(255, 255, 255, 0.09);
  }

  .btn--primary:hover:not(:disabled) {
    background: linear-gradient(135deg, #f6d271, #d7a941);
  }
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  background: rgba(0, 0, 0, 0.62);
  backdrop-filter: blur(8px);
}

.modal[hidden],
.modal .btn[hidden] {
  display: none;
}

.modal__content {
  width: min(100%, 340px);
  padding: 24px 20px;
  text-align: center;
  color: var(--color-text);
  background: rgba(8, 20, 36, 0.92);
  border: 1px solid rgba(241, 199, 91, 0.42);
  border-radius: 20px;
  box-shadow: 0 12px 42px rgba(0, 0, 0, 0.25);
}

.modal__title {
  margin-bottom: 8px;
  font-size: 1.4rem;
  color: var(--color-gold);
}

.modal__text {
  margin-bottom: 8px;
}

.modal__content .btn {
  margin-top: 10px;
}

@media (max-width: 980px) {
  .site-header__inner {
    align-items: flex-start;
    flex-wrap: wrap;
  }

  .site-nav--main {
    order: 3;
    flex-basis: 100%;
    justify-content: flex-start;
  }

  .site-header__tools {
    flex-basis: 100%;
    justify-content: flex-start;
  }

  .site-nav--services,
  .language-switcher {
    justify-content: flex-start;
  }

  .guide-video-section {
    grid-template-columns: 1fr;
    padding: 18px;
  }
}

@media (max-width: 560px) {
  body {
    padding: 10px 8px 24px;
  }

  .site-header {
    margin-bottom: 12px;
  }

  .site-header__inner {
    padding: 12px;
    border-radius: 18px;
  }

  .site-brand__logo {
    width: 44px;
    height: 44px;
  }

  .site-brand__text strong {
    font-size: 0.9rem;
  }

  .site-nav {
    gap: 8px;
  }

  .site-nav--main a {
    font-size: 0.86rem;
  }

  .site-service-link {
    min-height: 36px;
    padding: 6px 10px;
    font-size: 0.82rem;
  }

  .lang-character-btn {
    width: 46px;
    height: 46px;
    min-width: 46px;
    min-height: 46px;
  }

  .lang-character-img {
    width: 40px;
    height: 40px;
  }

  .guide-video-section {
    margin-bottom: 12px;
    padding: 16px 14px;
    border-radius: 18px;
  }

  .guide-video-copy h2 {
    font-size: 1.45rem;
  }

  .guide-video-frame {
    border-radius: 14px;
  }

  .guide-video-link {
    width: 100%;
  }
}

@media (min-width: 620px) {
  .app {
    max-width: 760px;
  }

  .app__title {
    font-size: 1.7rem;
  }

  .toolbar {
    grid-template-columns: 1fr 1.15fr 0.85fr 0.85fr;
    align-items: end;
  }

  .mode-picker,
  .stage-picker {
    grid-column: auto;
  }

  .board {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .card__word {
    font-size: clamp(1rem, 2.2vw, 1.45rem);
  }
}

.board.sentence-mode {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.board.sentence-mode .card {
  aspect-ratio: auto;
  min-height: 280px;
}

.board.sentence-mode .card__inner {
  min-height: 280px;
}

.board.sentence-mode .card__face {
  padding: 16px;
  overflow: visible;
}

.board.sentence-mode .card__back {
  overflow: hidden;
}

.board.sentence-mode .card__front {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 8px;
}

.board.sentence-mode .card__word {
  font-size: 1.22rem;
  line-height: 1.25;
  word-break: keep-all;
  overflow-wrap: anywhere;
}

.board.sentence-mode .card__vi {
  font-size: 0.95rem;
  line-height: 1.35;
  word-break: keep-all;
  overflow-wrap: anywhere;
}

.board.sentence-mode .card__en {
  font-size: 0.88rem;
  line-height: 1.35;
  overflow-wrap: anywhere;
}

.board.sentence-mode .card__pron {
  font-size: 0.82rem;
  line-height: 1.3;
  overflow-wrap: anywhere;
}

@media (min-width: 900px) {
  .board.sentence-mode {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .board.sentence-mode {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 520px) {
  .board.sentence-mode .card,
  .board.sentence-mode .card__inner {
    min-height: 260px;
  }

  .board.sentence-mode .card__face {
    padding: 14px;
  }

  .board.sentence-mode .card__word {
    font-size: 1.14rem;
  }
}