:root {
  --bg: #f0f4f8;
  --panel: #ffffff;
  --ink: #12202f;
  --muted: #607182;
  --line: #d9e3ec;
  --primary: #00706e;
  --primary-deep: #005e5c;
  --accent: #d97d17;
  --ok: #1f8d50;
  --warn: #b86d12;
  --danger: #c7433e;
  --radius: 8px;
  --shadow: 0 12px 28px rgba(0, 30, 60, 0.11);
  --control-height: 48px;
  --action-col-width: 188px;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  height: 100%;
}

body {
  color: var(--ink);
  font-family: "SF Pro Text", "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  letter-spacing: 0;
  background:
    radial-gradient(circle at 12% -8%, rgba(0, 112, 110, 0.2), transparent 36%),
    radial-gradient(circle at 90% 0%, rgba(217, 125, 23, 0.15), transparent 35%),
    var(--bg);
  overflow: hidden;
}

button,
input {
  font: inherit;
}

button {
  border: 0;
}

h1,
h2,
h3,
p {
  margin: 0;
}

.app-shell {
  width: min(1520px, calc(100vw - 16px));
  height: calc(100vh - 12px);
  margin: 6px auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 8px;
}

.main-panel,
.quiz-surface,
.rail-block,
.metric-card,
.settings-strip,
.topbar {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow);
}

.main-panel {
  min-width: 0;
  min-height: 0;
  padding: 10px;
  display: grid;
  grid-template-rows: auto auto auto minmax(0, 1fr);
  gap: 8px;
}

.topbar,
.brand-lockup,
.top-actions,
.settings-strip,
.setting-group,
.question-head,
.question-meta,
.feedback-row,
.action-cluster,
.section-head {
  display: flex;
  align-items: center;
}

.topbar,
.question-head,
.feedback-row {
  justify-content: space-between;
  gap: 12px;
}

.brand-lockup {
  gap: 8px;
}

.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  border-radius: var(--radius);
  color: #fff;
  font-size: 16px;
  font-weight: 800;
  background: linear-gradient(140deg, var(--primary), var(--accent));
}

.eyebrow {
  margin-bottom: 2px;
  color: var(--primary);
  font-size: 11px;
  font-weight: 800;
  text-transform: uppercase;
}

h1 {
  font-size: 19px;
  line-height: 1.18;
}

h2 {
  font-size: 18px;
  line-height: 1.24;
}

h3 {
  font-size: 18px;
}

.top-actions {
  gap: 6px;
}

.icon-button,
.mini-button,
.primary-button,
.tool-button {
  min-height: 34px;
  border-radius: var(--radius);
  cursor: pointer;
  color: var(--ink);
  font-weight: 700;
  background: #e8eef4;
  transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.12s ease;
}

.icon-button {
  width: 36px;
  display: grid;
  place-items: center;
  font-size: 16px;
}

a.icon-button {
  color: var(--ink);
  text-decoration: none;
}

.file-button {
  position: relative;
}

.danger {
  color: #fff;
  background: var(--danger);
}

.icon-button:hover,
.mini-button:hover,
.primary-button:hover,
.tool-button:hover {
  transform: translateY(-1px);
  box-shadow: 0 10px 20px rgba(0, 80, 90, 0.18);
}

.settings-strip {
  padding: 8px;
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 8px;
}

.setting-group {
  gap: 6px;
  flex-wrap: wrap;
}

.setting-group label {
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.setting-group input[type="number"] {
  width: 84px;
  height: 32px;
  padding: 0 8px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #f8fbfd;
}

.setting-group input[type="range"] {
  width: min(180px, 100%);
}

.toggle-line {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  white-space: nowrap;
}

.range-label {
  margin-left: auto;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
}

.mini-button {
  min-width: 78px;
  padding: 0 10px;
  background: #dce8f1;
}

.start-button {
  color: #fff;
  background: linear-gradient(140deg, var(--primary), var(--primary-deep));
}

.start-button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.stop-button {
  color: #fff;
  background: linear-gradient(140deg, #cf4a46, #b43734);
}

.metric-strip {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 8px;
}

.metric-card {
  padding: 8px 10px;
  box-shadow: none;
}

.metric-card span,
.answer-glance span {
  display: block;
  margin-bottom: 5px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 700;
  text-transform: uppercase;
}

.metric-card strong {
  font-size: 20px;
}

.quiz-surface {
  min-height: 0;
  padding: 10px;
  display: grid;
  grid-template-rows: max-content max-content max-content max-content max-content;
  grid-auto-rows: max-content;
  gap: 6px;
  align-content: start;
  align-self: start;
  height: max-content;
}

.reason-badge {
  min-width: 92px;
  height: 30px;
  padding: 0 12px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  color: #fff;
  font-size: 12px;
  font-weight: 800;
  background: var(--primary);
}

.question-meta {
  gap: 8px;
}

.hint-timer {
  min-width: 86px;
  height: 30px;
  padding: 0 8px 0 6px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid #cfdbe6;
  border-radius: 999px;
  background: #f7fbff;
}

.hint-timer.hidden {
  display: none;
}

.hint-timer.paused {
  border-color: #e2b980;
  background: #fff8ec;
}

.hint-timer-ring {
  --ring-deg: 360deg;
  position: relative;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: conic-gradient(var(--accent) var(--ring-deg), #dce5ee 0deg);
}

.hint-timer-ring::after {
  content: "";
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  background: #fff;
}

.hint-timer-text {
  color: #355067;
  font-size: 11px;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  letter-spacing: 0;
}

.prompt-block {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 10px;
  display: grid;
  gap: 8px;
  background: #fbfdff;
}

.ja-example {
  font-size: 20px;
  font-weight: 700;
  line-height: 1.38;
}

.en-masked {
  color: #1f384f;
  font-size: 16px;
  line-height: 1.42;
  white-space: pre-wrap;
}

.answer-form {
  display: grid;
  grid-template-columns: 1fr var(--action-col-width);
  gap: 8px;
  margin: 0;
  align-items: stretch;
}

#answerInput {
  width: 100%;
  height: var(--control-height);
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  font-size: 19px;
  font-weight: 700;
  background: #fff;
}

#answerInput:focus {
  outline: 2px solid rgba(0, 112, 110, 0.26);
  border-color: var(--primary);
}

.primary-button {
  color: #fff;
  font-size: 16px;
  background: linear-gradient(140deg, var(--primary), var(--primary-deep));
}

#submitButton {
  width: 100%;
  min-height: var(--control-height);
  height: var(--control-height);
}

.feedback-row {
  display: grid;
  grid-template-columns: 1fr var(--action-col-width);
  gap: 8px;
  margin: 0;
  align-items: stretch;
}

.answer-form + .feedback-row {
  margin-top: 0;
}

.feedback-panel {
  min-height: var(--control-height);
  padding: 8px 10px;
  border-radius: var(--radius);
  display: grid;
  gap: 3px;
  border: 1px solid transparent;
}

.feedback-panel strong {
  font-size: 15px;
}

.feedback-panel span {
  font-size: 13px;
  line-height: 1.35;
}

.feedback-panel.neutral {
  border-color: #c9d7e4;
  background: #f5f8fb;
}

.feedback-panel.correct {
  border-color: #b7e2c6;
  background: #effaf3;
  color: #186c3f;
}

.feedback-panel.wrong {
  border-color: #f4c8be;
  background: #fff3f0;
  color: #8f2f28;
}

.action-cluster {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 6px;
  min-height: var(--control-height);
  align-items: stretch;
  align-self: stretch;
}

.tool-button {
  min-width: 0;
  min-height: 34px;
  padding: 0 10px;
  background: #e5edf4;
}

.action-cluster .tool-button {
  min-height: var(--control-height);
  height: 100%;
}

.tool-button.strong {
  color: #fff;
  background: linear-gradient(140deg, var(--accent), #c96b10);
}

.tool-button:disabled,
.primary-button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.answer-glance {
  min-height: 72px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 6px 10px;
  display: grid;
  gap: 4px;
  background: #fbfdff;
}

.answer-glance strong {
  font-size: 18px;
}

.answer-meaning {
  border-top: 1px solid #e3ebf3;
  padding-top: 4px;
  display: grid;
  gap: 2px;
}

.answer-meaning-label {
  color: #5e7386;
  font-size: 11px;
  font-weight: 700;
}

.answer-meaning-text {
  margin: 0;
  color: #1f384f;
  font-size: 13px;
  line-height: 1.4;
  white-space: pre-wrap;
}

.side-panel {
  min-width: 0;
  min-height: 0;
  display: grid;
  grid-template-rows: 1fr;
  gap: 8px;
}

.rail-block {
  min-height: 0;
  padding: 10px;
  display: grid;
  grid-template-rows: auto 1fr;
  gap: 8px;
}

.section-head {
  justify-content: space-between;
}

.queue-list,
.log-list {
  min-height: 0;
  overflow: auto;
  display: grid;
  gap: 8px;
}

.queue-item,
.log-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 8px 10px;
  background: #fcfeff;
}

.queue-item strong,
.log-item strong {
  display: block;
  margin-bottom: 3px;
}

.queue-item span,
.log-item span:not(.badge) {
  color: #455b6f;
  font-size: 12px;
  line-height: 1.45;
}

.log-item {
  display: grid;
  gap: 4px;
}

.badge {
  width: fit-content;
  min-width: 46px;
  padding: 2px 8px;
  border-radius: 999px;
  color: #f8fbff;
  font-size: 11px;
  font-weight: 800;
  text-align: center;
  text-shadow: 0 1px 1px rgba(0, 0, 0, 0.25);
}

.badge.ok {
  background: var(--ok);
}

.badge.ng {
  background: var(--danger);
}

.badge.show {
  background: var(--warn);
}

.badge.hint {
  background: #2e77c8;
}

.empty {
  color: #6b7f90;
}

.shake {
  animation: shake 0.24s ease;
}

@keyframes shake {
  0% { transform: translateX(0); }
  25% { transform: translateX(-4px); }
  50% { transform: translateX(4px); }
  75% { transform: translateX(-3px); }
  100% { transform: translateX(0); }
}

@media (max-width: 1180px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .side-panel {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr;
  }
}

@media (max-width: 880px) {
  .settings-strip {
    grid-template-columns: 1fr;
  }

  .metric-strip {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .answer-form {
    grid-template-columns: 1fr;
  }

  .feedback-row {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .action-cluster {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .side-panel {
    grid-template-columns: 1fr;
  }

  .ja-example {
    font-size: 20px;
  }
}