/* 成长岔路口 · 各页面共用：暖纸底；橙色 = 顺境，蓝色 = 逆境，绿色 = AI 生成。PPT 风格定了以后只改这里的颜色和字体 */
:root {
  --ink: #1d2a44;
  --ink-soft: #4a5568;
  --muted: #8a8f99;
  --paper: #f6f3ec;
  --card: #ffffff;
  --line: #e6e0d4;
  --sun: #e07b2e;
  --sun-deep: #c4621a;
  --sun-soft: #fdf0e3;
  --sea: #2c66a8;
  --sea-deep: #1f4f86;
  --sea-soft: #e8f0fa;
  --ai: #1f9a74;
  --ai-soft: #e4f5ee;
  --red: #b8423a;
  --shadow: 0 0.2rem 0.8rem rgba(29, 42, 68, 0.08);
  --title: 'STKaiti', 'KaiTi', 'Kaiti SC', 'KaiTi_GB2312', serif;
  /* 一体机 1920×1080 约 28px；1280×720 开 150% 缩放时 CSS 只有 853×480，最小 14px */
  font-size: clamp(14px, min(1.6vw, 2.65vh), 34px);
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

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

body {
  color: var(--ink);
  background: var(--paper);
  font-family: 'HarmonyOS Sans SC', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
  line-height: 1.6;
  -webkit-tap-highlight-color: transparent;
}

button {
  font: inherit;
  color: inherit;
  cursor: pointer;
  -webkit-touch-callout: none;
  user-select: none;
}

textarea,
input {
  font: inherit;
  color: inherit;
}

/* —— 大屏页面：顶栏 + 主区，铺满一屏不滚动 */
.screen {
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

.bar {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.55rem 1.2rem;
  background: #fff;
  border-bottom: 1px solid var(--line);
  flex: none;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.7rem;
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
}

.brand::before {
  content: '';
  width: 1.1rem;
  height: 1.1rem;
  border-radius: 50%;
  background: conic-gradient(var(--sun) 0 50%, var(--sea) 50% 100%);
  flex: none;
}

.bar h1 {
  margin: 0;
  font-family: var(--title);
  font-size: 1.35rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  white-space: nowrap;
}

.bar .sub {
  color: var(--ink-soft);
  font-size: 0.75rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  min-width: 0;
}

.bar .tools {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex: none;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.35em;
  padding: 0.4em 0.95em;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fff;
  font-size: 0.72rem;
  line-height: 1.3;
  white-space: nowrap;
  text-decoration: none;
  color: var(--ink);
  transition: background 0.15s, transform 0.1s;
}

.btn:hover {
  background: #faf7f0;
}

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

.btn:disabled {
  opacity: 0.5;
  cursor: default;
}

.btn.primary {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}

.btn.sun {
  background: var(--sun);
  border-color: var(--sun);
  color: #fff;
}

.btn.sea {
  background: var(--sea);
  border-color: var(--sea);
  color: #fff;
}

.btn.ai {
  background: var(--ai);
  border-color: var(--ai);
  color: #fff;
}

.btn.big {
  font-size: 0.95rem;
  padding: 0.55em 1.4em;
}

.btn.on {
  background: var(--ink);
  color: #fff;
}

/* 比赛要求：AI 生成的内容显著标明“由AI生成” */
.ai-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.25em;
  padding: 0.12em 0.6em;
  border-radius: 999px;
  background: var(--ai-soft);
  color: var(--ai);
  font-size: 0.6rem;
  font-weight: 600;
  white-space: nowrap;
  vertical-align: middle;
}

.ai-tag::before {
  content: '✦';
}

.demo-flag {
  display: none;
  padding: 0.12em 0.6em;
  border-radius: 999px;
  background: #fff3cd;
  color: #8a6100;
  font-size: 0.6rem;
  white-space: nowrap;
}

.is-demo .demo-flag {
  display: inline-block;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 0.8rem;
  box-shadow: var(--shadow);
}

.qr svg {
  display: block;
  width: 100%;
  height: auto;
}

.toast {
  position: fixed;
  left: 50%;
  bottom: 1.6rem;
  transform: translate(-50%, 1rem);
  max-width: 80vw;
  padding: 0.55em 1.2em;
  border-radius: 999px;
  background: rgba(29, 42, 68, 0.92);
  color: #fff;
  font-size: 0.8rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s;
  z-index: 99;
}

.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

.spin {
  display: inline-block;
  width: 1em;
  height: 1em;
  border: 0.14em solid currentColor;
  border-right-color: transparent;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  vertical-align: -0.12em;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* 话筒音量条 */
.level {
  display: inline-flex;
  align-items: center;
  gap: 0.12em;
  height: 1em;
}

.level i {
  width: 0.16em;
  height: 12%;
  border-radius: 0.1em;
  background: currentColor;
  transition: height 0.08s;
}

/* 弹窗（二维码、详情） */
.mask {
  position: fixed;
  inset: 0;
  background: rgba(29, 42, 68, 0.45);
  display: grid;
  place-items: center;
  z-index: 50;
}

.qr-box {
  display: flex;
  gap: 1.2rem;
  align-items: center;
  max-width: 80vw;
  padding: 1.2rem 1.4rem;
}

.qr-box .qr {
  width: 11rem;
  flex: none;
}

.qr-box h3 {
  margin: 0 0 0.4rem;
}

.qr-box p {
  margin: 0 0 0.4rem;
  font-size: 0.8rem;
}

.qr-box .muted {
  color: var(--muted);
  font-size: 0.62rem;
  word-break: break-all;
}