/* MQ Style4 登录/注册页（WE-2466）— 本地 Noto（中西文） */
@import url("mq-style4-fonts.css");

.mq-style4-root,
.mq-style4-root * {
  box-sizing: border-box;
}

/* 抵消站点全局 / UA 默认边距，与原型 *{margin:0} 对齐 */
.mq-style4-root h1,
.mq-style4-root h2,
.mq-style4-root h3,
.mq-style4-root p,
.mq-style4-root ul,
.mq-style4-root ol,
.mq-style4-root figure {
  margin: 0;
  padding: 0;
}

/*
 * 登录分步 #step1/#step2 会打断 field↔.row 的 margin 折叠（原型为扁平 DOM）。
 * 去掉末字段 bottom margin，并把 .row 的 top 调到折叠后的 18px。
 */
.mq-style4-root #step1 > .field:nth-child(2),
.mq-style4-root #step2 > .field:last-child {
  margin-bottom: 0;
}

.mq-style4-root .card > .row {
  margin-top: 18px;
}

.mq-style4-root {
  --mq-ink: #070E1C;
  --mq-paper: #FFFFFF;
  --mq-mist: #C8D6E4;
  --mq-mist2: #DCE7F2;
  --mq-dim: #93A7BC;
  --mq-line: rgba(200, 214, 228, .15);
  --mq-coral: #F4564A;
  --mq-red: #F4564A;
  --mq-blue: #4AA8E8;
  --mq-teal: #4FD6C0;
  --mq-cyan: #37B6E9;
  --mq-gold: #F2B441;
  --mq-btn1: #F4712E;
  --mq-btn2: #E62F52;
  /* 中西文均走本地 Noto */
  --mq-sans: "Noto Sans TC", "Noto Sans SC", "PingFang TC", "Microsoft JhengHei", "Microsoft YaHei", sans-serif;
  --mq-mono: ui-monospace, "Cascadia Mono", "Consolas", monospace;
  min-height: 100vh;
  width: 100%;
  max-width: 100%;
  background: var(--mq-ink);
  color: var(--mq-paper);
  font-family: var(--mq-sans);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}

.mq-style4-root html[lang="zh-Hans"],
.mq-style4-root:lang(zh-Hans) {
  --mq-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

/* Style4：覆盖 parentSigin 的 html/body overflow:hidden + height:100%，允许小屏纵向滚动 */
html.mq-style4-active,
#login_bg.mq-style4-active,
body.mq-style4-active {
  height: auto;
  min-height: 100%;
  overflow-x: hidden;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

body.mq-style4-active #app {
  height: auto;
  min-height: 100%;
  overflow: visible;
}

/* Style4 使用 shell 内 footer，隐藏旧版全局 tinytext */
body.mq-style4-active #tinytext {
  display: none !important;
}

.mq-style4-root #mq-bg {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  display: block;
  pointer-events: none;
  background: var(--mq-ink);
}

.mq-style4-root .bgblur {
  display: none;
}

@media (max-width: 900px) {
  .mq-style4-root .bgblur {
    display: block;
    position: fixed;
    inset: 0;
    z-index: 1;
    pointer-events: none;
    /* 与原型一致：小屏不用初始模糊盖住光弧；滚动后再柔化 */
    backdrop-filter: blur(var(--bgb, 0px));
    -webkit-backdrop-filter: blur(var(--bgb, 0px));
    background: transparent;
  }
}

.mq-style4-root .vig {
  position: fixed;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: radial-gradient(135% 105% at 50% 45%, transparent 58%, rgba(3, 7, 14, .34) 100%);
}

.mq-style4-root .shell {
  position: relative;
  z-index: 2;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding: 20px clamp(20px, 3.4vw, 64px) 0 clamp(16px, 2.6vw, 44px);
  overflow-x: hidden;
  max-width: 100vw;
}

.mq-style4-root .top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
}

.mq-style4-root .mark {
  display: flex;
  align-items: center;
  gap: 13px;
  text-decoration: none;
  color: inherit;
}

.mq-style4-root .mark .mq {
  font-weight: 900;
  font-size: clamp(30px, 3.2vw, 42px);
  letter-spacing: -2.5px;
  line-height: 1;
  flex: none;
}

.mq-style4-root .mark .mq .m { color: var(--mq-coral); }
.mq-style4-root .mark .mq .q { color: var(--mq-cyan); }
.mq-style4-root .mark .mq sup {
  font-size: .3em;
  letter-spacing: 0;
  color: var(--mq-mist);
  top: -1.4em;
  position: relative;
}

.mq-style4-root .mark .lock {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding-left: 13px;
  border-left: 1px solid rgba(200, 214, 228, .22);
}

.mq-style4-root .mark .full {
  font-weight: 700;
  font-size: clamp(14px, 1.25vw, 18px);
  /* 与原型一致：不加 letter-spacing，避免英文标题被拉开 */
  letter-spacing: normal;
  color: var(--mq-paper);
  line-height: 1.15;
}

.mq-style4-root .mark .full sup {
  font-size: .52em;
  color: var(--mq-mist);
  top: -.85em;
  position: relative;
}

.mq-style4-root .mark .by {
  font-size: 11.5px;
  color: var(--mq-dim);
  letter-spacing: normal;
  line-height: 1.2;
}

.mq-style4-root .top nav {
  display: flex;
  gap: 26px;
  font-size: 14px;
}

.mq-style4-root .top nav a {
  color: var(--mq-mist);
  text-decoration: none;
  transition: color .2s;
  white-space: nowrap;
}

.mq-style4-root .top nav a:hover { color: var(--mq-paper); }

.mq-style4-root .main {
  flex: 1;
  min-width: 0;
  max-width: 100%;
  display: grid;
  grid-template-areas: "a c" "b c";
  grid-template-columns: minmax(0, 1fr) clamp(366px, 28vw, 438px);
  grid-template-rows: auto auto;
  align-content: center;
  gap: clamp(4px, 0.8vh, 12px) clamp(26px, 3.2vw, 54px);
  padding: clamp(12px, 2.5vh, 38px) 0;
}

.mq-style4-root .hero-a {
  grid-area: a;
  align-self: end;
  will-change: transform;
  text-align: center;
  min-width: 0;
}

.mq-style4-root .hero-b {
  grid-area: b;
  align-self: start;
  text-align: center;
  min-width: 0;
}

.mq-style4-root .lede {
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 0;
}

.mq-style4-root .method {
  justify-content: center;
}

.mq-style4-root .keys {
  justify-content: center;
}

.mq-style4-root .card {
  grid-area: c;
  align-self: center;
  justify-self: start;
  min-width: 0;
  width: 100%;
  max-width: 438px;
  background: linear-gradient(160deg, rgba(19, 32, 52, .93), rgba(10, 18, 31, .96));
  border: 1px solid rgba(212, 228, 244, .38);
  border-radius: 20px;
  padding: clamp(32px, 3.2vw, 46px) clamp(28px, 3vw, 42px) clamp(26px, 2.6vw, 36px);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  box-shadow: 0 54px 120px -40px rgba(0, 0, 0, .98),
    inset 0 1px 0 rgba(255, 255, 255, .10),
    inset 0 -1px 0 rgba(0, 0, 0, .4);
  position: relative;
  overflow: hidden;
}

.mq-style4-root h1 {
  font-weight: 800;
  font-size: clamp(32px, 4.4vw, 62px);
  line-height: 0.60;
  letter-spacing: .005em;
  margin: 0;
  text-shadow: 0 0 44px rgba(255, 196, 140, .3), 0 0 96px rgba(255, 150, 90, .17);
}

.mq-style4-root h1 #mq-h1a,
.mq-style4-root h1 #mq-h1b {
  display: block;
  white-space: nowrap;
}

.mq-style4-root h1 .u {
  display: inline-block;
  vertical-align: top;
  line-height: .9;
  opacity: 0;
  transform: translateY(20px);
  animation: mqPop .8s cubic-bezier(.2, .9, .3, 1) forwards;
}

.mq-style4-root .lede {
  margin-top: clamp(24px, 3.4vh, 40px);
  color: var(--mq-mist);
  font-size: clamp(14.5px, 1.12vw, 18.5px);
  line-height: 1.8;
  max-width: 64ch;
}

.mq-style4-root .method {
  margin-top: 0;
  display: flex;
  align-items: center;
  gap: clamp(9px, 1.15vw, 16px);
  flex-wrap: nowrap;
  white-space: nowrap;
  font-weight: 700;
  font-size: clamp(18px, 1.95vw, 28px);
}

.mq-style4-root .method .m1 { color: var(--mq-red); }
.mq-style4-root .method .m2 { color: var(--mq-blue); }
.mq-style4-root .method .m3 { color: var(--mq-teal); }
.mq-style4-root .method .x {
  color: var(--mq-dim);
  font-weight: 400;
  font-size: .8em;
}
.mq-style4-root .method span { text-shadow: 0 0 26px currentColor; }

.mq-style4-root .keys {
  display: flex;
  align-items: stretch;
  flex-wrap: nowrap;
  margin-top: clamp(96px, 15vh, 215px);
}

.mq-style4-root .key {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 6px clamp(10px, 1.35vw, 22px) 14px;
  color: var(--mq-dim);
  transition: color .5s ease, transform .5s ease;
}

.mq-style4-root .key + .key { border-left: 1px solid var(--mq-line); }

.mq-style4-root .key svg {
  width: clamp(30px, 3.1vw, 44px);
  height: clamp(30px, 3.1vw, 44px);
  stroke-width: 1.55;
  opacity: .82;
  filter: saturate(.82);
}

.mq-style4-root .key b {
  font-weight: 600;
  font-size: clamp(15px, 1.55vw, 21px);
  white-space: nowrap;
}

.mq-style4-root .key::after {
  content: "";
  position: absolute;
  left: clamp(10px, 1.35vw, 22px);
  right: clamp(10px, 1.35vw, 22px);
  bottom: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--mq-cyan);
  transform: scaleX(0);
  transition: transform .5s cubic-bezier(.2, .9, .3, 1);
}

.mq-style4-root .key.on {
  color: var(--mq-paper);
  transform: translateY(-2px);
}

.mq-style4-root .key.on svg {
  color: var(--mq-cyan);
  opacity: .9;
  filter: saturate(.85) drop-shadow(0 0 9px rgba(55, 182, 233, .34));
}

.mq-style4-root .key.on::after { transform: scaleX(1); }

.mq-style4-root .card::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 18px;
  pointer-events: none;
  padding: 1.6px;
  background: linear-gradient(134deg, rgba(255, 255, 255, .88) 0%, rgba(130, 220, 250, .5) 20%,
    rgba(255, 255, 255, .14) 44%, rgba(255, 255, 255, .06) 70%, rgba(255, 255, 255, .16) 100%);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  mask-composite: exclude;
}

.mq-style4-root .card::before {
  content: "";
  position: absolute;
  top: 0;
  left: -30%;
  width: 60%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--mq-cyan), transparent);
  animation: mqEdge 9s linear infinite;
}

@keyframes mqEdge { to { left: 130%; } }
@keyframes mqPop { to { opacity: 1; transform: none; } }

.mq-style4-root .card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 20px;
}

.mq-style4-root .card-top.tight { margin-bottom: 20px; }

.mq-style4-root .card h2 {
  font-size: clamp(24px, 2.1vw, 30px);
  font-weight: 700;
  letter-spacing: .01em;
  margin: 0;
  /* 与原型一致：用默认行高，避免「登录」被压扁 */
  line-height: normal;
}

.mq-style4-root .card h2 small {
  display: block;
  font-size: 14.5px;
  font-weight: 400;
  color: #C6D6E6;
  margin-top: 8px;
  letter-spacing: 0;
}

.mq-style4-root .card .hint {
  font-size: 14.5px;
  color: #C6D6E6;
  line-height: 1.8;
  margin: -6px 0 22px;
}

.mq-style4-root .lang {
  font-size: 13.5px;
  color: #DCE7F2;
  background: rgba(255, 255, 255, .05);
  font-family: var(--mq-sans);
  border: 1px solid var(--mq-line);
  border-radius: 9px;
  padding: 8px 11px;
  cursor: pointer;
  /* 与原型一致：保留原生下拉箭头 */
  -webkit-appearance: menulist;
  -moz-appearance: menulist;
  appearance: menulist;
  flex: none;
  max-width: 160px;
  height: auto;
  line-height: normal;
}

.mq-style4-root .lang:hover { border-color: rgba(55, 182, 233, .55); }

.mq-style4-root .lang option { background: #0C2136; color: var(--mq-paper); }

/* 自定义语言选择：隐藏原生 select，避免移动端系统白底弹层 */
.mq-style4-root .mq-lang {
  position: relative;
  flex: none;
  z-index: 20;
}

.mq-style4-root .mq-lang-native {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  border: 0 !important;
  opacity: 0 !important;
  pointer-events: none !important;
}

.mq-style4-root .mq-lang-trigger {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--mq-sans);
  font-size: 13.5px;
  color: #DCE7F2;
  background: rgba(255, 255, 255, .05);
  border: 1px solid var(--mq-line);
  border-radius: 9px;
  padding: 8px 11px;
  cursor: pointer;
  max-width: 150px;
  transition: color .2s, border-color .2s, background .2s;
}

.mq-style4-root .mq-lang-trigger:hover,
.mq-style4-root .mq-lang.is-open .mq-lang-trigger {
  color: var(--mq-paper);
  border-color: rgba(69, 190, 220, .55);
  background: rgba(69, 190, 220, .1);
}

.mq-style4-root .mq-lang-label {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.mq-style4-root .mq-lang-chevron {
  display: inline-flex;
  flex: none;
  opacity: .75;
  transition: transform .2s ease;
}

.mq-style4-root .mq-lang.is-open .mq-lang-chevron {
  transform: rotate(180deg);
}

.mq-style4-root .mq-lang-backdrop {
  position: fixed;
  inset: 0;
  z-index: 80;
  background: rgba(4, 10, 18, .55);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity .2s ease, visibility .2s;
}

@media (min-width: 901px) {
  .mq-style4-root .mq-lang-backdrop {
    display: none;
  }
}

.mq-style4-root .mq-lang-backdrop.is-open {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.mq-style4-root .mq-lang-panel {
  position: fixed;
  z-index: 90;
  min-width: 188px;
  padding: 6px;
  border-radius: 14px;
  background: linear-gradient(165deg, rgba(12, 33, 54, .98), rgba(8, 20, 32, .98));
  border: 1px solid rgba(182, 200, 216, .22);
  box-shadow: 0 16px 40px rgba(0, 0, 0, .45), 0 0 0 1px rgba(69, 190, 220, .08);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px) scale(.98);
  transform-origin: top right;
  transition: opacity .18s ease, transform .18s ease, visibility .18s;
  pointer-events: none;
}

.mq-style4-root .mq-lang-panel.is-open {
  opacity: 1;
  visibility: visible;
  transform: none;
  pointer-events: auto;
}

.mq-style4-root .mq-lang-option {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  width: 100%;
  border: 0;
  background: transparent;
  color: var(--mq-mist2);
  font-family: var(--mq-sans);
  font-size: 14px;
  text-align: left;
  padding: 11px 12px;
  border-radius: 10px;
  cursor: pointer;
  transition: background .15s, color .15s;
}

.mq-style4-root .mq-lang-option:hover,
.mq-style4-root .mq-lang-option:focus {
  outline: none;
  background: rgba(69, 190, 220, .12);
  color: var(--mq-paper);
}

.mq-style4-root .mq-lang-option.is-active {
  color: var(--mq-paper);
  background: rgba(69, 190, 220, .16);
}

.mq-style4-root .mq-lang-check {
  display: inline-flex;
  color: var(--mq-cyan);
  opacity: 0;
  flex: none;
}

.mq-style4-root .mq-lang-option.is-active .mq-lang-check {
  opacity: 1;
}

/* 表单字段型下拉（学校/角色等）：与输入框同宽同高 */
.mq-style4-root .mq-lang--field {
  width: 100%;
  display: block;
}

.mq-style4-root .mq-lang--field .mq-lang-trigger {
  width: 100%;
  max-width: none;
  height: 49px;
  box-sizing: border-box;
  justify-content: space-between;
  gap: 10px;
  padding: 0 14px;
  border-radius: 11px;
  border: 1.5px solid rgba(217, 232, 241, .34);
  background: rgba(8, 20, 32, .5);
  color: var(--mq-paper);
  font-family: var(--mq-sans);
  font-size: 15.5px;
}

.mq-style4-root .mq-lang--field.is-placeholder .mq-lang-label {
  color: rgba(220, 232, 241, .62);
}

.mq-style4-root .mq-lang--field .mq-lang-trigger:hover,
.mq-style4-root .mq-lang--field.is-open .mq-lang-trigger {
  border-color: var(--mq-cyan);
  background: rgba(69, 190, 220, .12);
  box-shadow: 0 0 0 3px rgba(69, 190, 220, .22);
  color: var(--mq-paper);
}

.mq-style4-root .mq-lang--field .mq-lang-chevron {
  opacity: .85;
  color: var(--mq-mist2);
}

.mq-style4-root .mq-lang-panel {
  max-height: min(60vh, 360px);
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.mq-style4-root .mq-lang-option.is-disabled {
  opacity: .45;
  cursor: default;
}

.mq-style4-root .field { margin-bottom: 18px; }

.mq-style4-root .field label {
  display: block;
  font-size: 15px;
  color: #DDE8F2;
  margin-bottom: 10px;
  font-weight: 500;
  letter-spacing: 0;
  text-transform: none;
  font-family: var(--mq-sans);
}

.mq-style4-root .field label i {
  font-style: normal;
  color: var(--mq-coral);
  margin-left: 3px;
}

.mq-style4-root .pair {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

.mq-style4-root .wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.mq-style4-root .wrap .lead {
  position: absolute;
  left: 16px;
  color: #B9CCDE;
  line-height: 0;
  pointer-events: none;
  z-index: 1;
  transition: color .2s;
}

.mq-style4-root .field input:not([type="button"]):not([type="submit"]),
.mq-style4-root .field select.mq-select {
  width: 100%;
  height: 58px;
  padding: 0 50px;
  font-size: 16.5px;
  font-family: var(--mq-sans);
  color: #F2F7FC;
  background: rgba(255, 255, 255, .06);
  border: 1px solid rgba(206, 222, 238, .26);
  border-radius: 11px;
  outline: none;
  transition: border-color .2s, background .2s, box-shadow .2s;
}

.mq-style4-root .field input.plain-left { padding-left: 14px; }
/* 带左侧图标的输入框：保证文字不被图标遮挡 */
.mq-style4-root .wrap > .lead + input:not([type="button"]),
.mq-style4-root .wrap > .lead + select { padding-left: 40px; }

.mq-style4-root .field input:not([type="button"])::placeholder { color: rgba(198, 214, 232, .62); }

.mq-style4-root .field input:not([type="button"]):not([type="submit"]):focus,
.mq-style4-root .field select.mq-select:focus {
  border-color: var(--mq-cyan);
  background: rgba(55, 182, 233, .09);
  box-shadow: 0 0 0 3px rgba(55, 182, 233, .2);
}

/* 浏览器自动填充：覆盖 Chrome 默认浅蓝底/黑字，保持 Style4 深色输入框与左侧图标可见 */
.mq-style4-root .field input:not([type="button"]):not([type="submit"]):-webkit-autofill,
.mq-style4-root .field input:not([type="button"]):not([type="submit"]):-webkit-autofill:hover,
.mq-style4-root .field input:not([type="button"]):not([type="submit"]):-webkit-autofill:focus,
.mq-style4-root .field input:not([type="button"]):not([type="submit"]):-webkit-autofill:active {
  -webkit-text-fill-color: var(--mq-paper) !important;
  caret-color: var(--mq-paper);
  border: 1.5px solid rgba(217, 232, 241, .34);
  -webkit-box-shadow: 0 0 0 1000px rgba(8, 20, 32, .5) inset !important;
  box-shadow: 0 0 0 1000px rgba(8, 20, 32, .5) inset !important;
  transition: background-color 600000s ease-in-out 0s;
}

.mq-style4-root .field input:not([type="button"]):not([type="submit"]):-webkit-autofill:focus {
  border-color: var(--mq-cyan);
  -webkit-box-shadow: 0 0 0 1000px rgba(69, 190, 220, .12) inset, 0 0 0 3px rgba(69, 190, 220, .22) !important;
  box-shadow: 0 0 0 1000px rgba(69, 190, 220, .12) inset, 0 0 0 3px rgba(69, 190, 220, .22) !important;
}

.mq-style4-root .wrap:has(input:-webkit-autofill) .lead {
  color: var(--mq-mist2);
  opacity: .95;
}

/* 原生下拉展开列表：避免白底继承白字导致选项不可见 */
.mq-style4-root .field select.mq-select option {
  background: #0C2136;
  color: var(--mq-paper);
}

.mq-style4-root .wrap:focus-within .lead { color: var(--mq-cyan); }

/* Style4 邮箱验证按钮：勿继承 field input 的 width:100% */
.mq-style4-root .mq-verify-btn,
.mq-style4-root input.mq-verify-btn[type="button"] {
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  z-index: 3;
  width: auto;
  min-width: 64px;
  max-width: 90px;
  white-space: nowrap;
  cursor: pointer;
  background: rgba(69, 190, 220, .35);
  border: 1px solid rgba(69, 190, 220, .65);
  color: var(--mq-paper);
  font-family: var(--mq-sans);
  font-size: 12.5px;
  font-weight: 600;
  border-radius: 9px;
  padding: 0 12px;
  height: 36px;
  line-height: 36px;
  box-shadow: none;
  -webkit-appearance: none;
  appearance: none;
}
.mq-style4-root .mq-verify-btn:hover {
  background: rgba(69, 190, 220, .5);
}
.mq-style4-root .mq-verify-btn.verify-btn-disabled,
.mq-style4-root .mq-verify-btn:disabled {
  background: rgba(182, 200, 216, .2);
  border-color: rgba(182, 200, 216, .3);
  color: var(--mq-mist);
  cursor: not-allowed;
}
.mq-style4-root .wrap.has-verify > input:not([type="button"]) {
  padding-right: 96px;
}

.mq-style4-root .peek {
  position: absolute;
  right: 7px;
  background: none;
  border: 0;
  cursor: pointer;
  color: var(--mq-mist2);
  opacity: .85;
  padding: 9px;
  line-height: 0;
  border-radius: 9px;
}

.mq-style4-root .peek:hover { color: var(--mq-cyan); }

.mq-style4-root .row,
.mq-style4-root .row-links {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin: 16px 0 24px;
  font-size: 14.5px;
  flex-wrap: wrap;
}

.mq-style4-root .keep {
  display: flex;
  align-items: center;
  gap: 10px;
  color: #D2DFEC;
  font-size: 14.5px;
  cursor: pointer;
  user-select: none;
}

.mq-style4-root .keep input {
  accent-color: var(--mq-cyan);
  width: 15px;
  height: 15px;
  cursor: pointer;
  flex: none;
}

.mq-style4-root a.link,
.mq-style4-root a.mq-link {
  color: var(--mq-cyan);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .2s;
}

.mq-style4-root a.link:hover,
.mq-style4-root a.mq-link:hover { border-color: var(--mq-cyan); }

.mq-style4-root .links { display: flex; gap: 16px; flex-wrap: wrap; }

.mq-style4-root .go {
  width: 100%;
  height: 60px;
  border: 0;
  border-radius: 12px;
  cursor: pointer;
  color: #fff;
  font-family: var(--mq-sans);
  font-size: 17.5px;
  font-weight: 700;
  letter-spacing: .1em;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 11px;
  padding: 0;
  background: linear-gradient(96deg, var(--mq-btn1), var(--mq-btn2));
  background-size: 180% 100%;
  box-shadow: 0 16px 38px -16px rgba(230, 47, 82, .9);
  transition: transform .18s ease, box-shadow .18s ease, background-position .8s ease;
  margin-top: 0;
}

.mq-style4-root .go svg { transition: transform .22s ease; flex: none; }

.mq-style4-root .go:hover {
  transform: translateY(-2px);
  background-position: 100% 0;
  box-shadow: 0 22px 46px -16px rgba(244, 113, 46, .85);
}

.mq-style4-root .go:hover svg { transform: translateX(5px); }
.mq-style4-root .go:active { transform: translateY(0); }

.mq-style4-root .card-foot {
  margin-top: 22px;
  padding-top: 20px;
  border-top: 1px solid var(--mq-line);
  text-align: center;
  font-size: 15px;
  color: #DCE7F2;
}

.mq-style4-root .card-foot .alt {
  color: var(--mq-btn1);
  text-decoration: none;
  font-weight: 500;
}

.mq-style4-root .card-foot .alt:hover { text-decoration: underline; }

.mq-style4-root .note {
  margin-top: 16px;
  font-size: 13px;
  line-height: 1.8;
  color: #B6C7D8;
}

.mq-style4-root .mq-error {
  margin: 0 0 12px;
  font-size: 13px;
  line-height: 1.5;
  color: #ffb4b4;
}

.mq-style4-root .mq-error:empty {
  display: none;
}

.mq-style4-root .mq-error .validation-summary-valid {
  display: none;
}

.mq-style4-root .mq-error .validation-summary-errors ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

.mq-style4-root .mq-error .validation-summary-errors li {
  margin: 0;
  padding: 0;
  color: inherit;
}

.mq-style4-root .bottom {
  padding: 16px 0 18px;
  font-size: 11.5px;
  letter-spacing: .05em;
  color: var(--mq-dim);
  opacity: .75;
  display: flex;
  justify-content: space-between;
  gap: 14px;
  flex-wrap: wrap;
}

.mq-style4-root .bottom a { color: inherit; text-decoration: none; }
.mq-style4-root .bottom a:hover { color: var(--mq-cyan); }

.mq-style4-root .bottom-links {
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
}

.mq-style4-root .bottom-dot {
  margin: 0 8px;
  opacity: .75;
}

.mq-style4-root .rise {
  opacity: 0;
  transform: translateY(18px);
  animation: mqRise .9s cubic-bezier(.22, 1, .36, 1) forwards;
}

@keyframes mqRise { to { opacity: 1; transform: none; } }

.mq-style4-root :focus-visible {
  outline: 2px solid var(--mq-cyan);
  outline-offset: 3px;
  border-radius: 7px;
}

.mq-style4-root .session-name {
  font-size: 14px;
  color: var(--mq-mist2);
  margin-bottom: 12px;
}

@media (prefers-reduced-motion: reduce) {
  .mq-style4-root .rise,
  .mq-style4-root h1 .u { animation: none; opacity: 1; transform: none; }
  .mq-style4-root .card::before { animation: none; }
  .mq-style4-root .key { color: var(--mq-mist); }
}

@media (max-width: 1080px) {
  .mq-style4-root .main {
    grid-template-areas: "a" "c" "b";
    grid-template-columns: 1fr;
    justify-items: center;
    text-align: center;
    gap: 26px;
  }
  .mq-style4-root .hero-a,
  .mq-style4-root .hero-b { max-width: 100%; padding-left: 0; }
  .mq-style4-root .method,
  .mq-style4-root .keys { justify-content: center; }
  .mq-style4-root .card { text-align: left; justify-self: center; }
  .mq-style4-root .lede { max-width: 54ch; margin-left: auto; margin-right: auto; }
}

@media (max-width: 900px) {
  .mq-style4-root .card {
    max-width: 100%;
    width: 100%;
    background: linear-gradient(160deg, rgba(17, 29, 48, .40), rgba(9, 16, 29, .56));
    backdrop-filter: blur(22px) saturate(128%);
    -webkit-backdrop-filter: blur(22px) saturate(128%);
    border-color: rgba(212, 228, 244, .32);
  }
  .mq-style4-root .field input:not([type="button"]):not([type="submit"]),
  .mq-style4-root .field select.mq-select {
    background: rgba(8, 16, 28, .50);
  }
  .mq-style4-root .main { width: 100%; }
  .mq-style4-root .lede { max-width: 46ch; }
  .mq-style4-root .shell {
    min-height: auto;
    padding-bottom: max(20px, env(safe-area-inset-bottom));
  }
  .mq-style4-root .mq-lang-backdrop { background: rgba(4, 10, 18, .62); }
  .mq-style4-root .mq-lang-panel {
    top: auto !important;
    left: 12px !important;
    right: 12px !important;
    bottom: max(12px, env(safe-area-inset-bottom));
    width: auto !important;
    min-width: 0;
    padding: 10px 8px calc(10px + env(safe-area-inset-bottom));
    border-radius: 18px;
    transform: translateY(18px);
    transform-origin: bottom center;
    box-shadow: 0 -8px 40px rgba(0, 0, 0, .5);
  }
  .mq-style4-root .mq-lang-panel.is-open { transform: none; }
  .mq-style4-root .mq-lang-option {
    font-size: 16px;
    padding: 14px 14px;
    border-radius: 12px;
  }
}

@media (max-width: 860px) {
  /* 小屏：隐藏导航，顶部 MQ 品牌居中 */
  .mq-style4-root .top {
    justify-content: center;
  }
  .mq-style4-root .top nav { display: none; }
}

@media (max-width: 640px) {
  .mq-style4-root .shell { padding: 18px 16px 0; }
  .mq-style4-root .mark .mq { font-size: 29px; }
  .mq-style4-root .mark .full { font-size: 14px; }
  .mq-style4-root .main { padding: 12px 0 0; gap: 20px; }
  .mq-style4-root h1 { line-height: 0.6; }
  .mq-style4-root h1 #mq-h1a,
  .mq-style4-root h1 #mq-h1b { margin-bottom: -.02em; }
  .mq-style4-root .lede {
    max-width: 46ch;
    font-size: 15.5px;
    line-height: 1.75;
    margin-top: 14px;
    color: #F5F9FD;
    text-shadow: 0 1px 12px rgba(4, 10, 20, .92), 0 0 30px rgba(4, 10, 20, .8);
    display: -webkit-box;
    -webkit-line-clamp: 4;
    -webkit-box-orient: vertical;
    overflow: hidden;
  }
  .mq-style4-root .hero-a { position: relative; }
  .mq-style4-root .hero-a::before {
    content: "";
    position: absolute;
    inset: -22px -16px -14px -16px;
    z-index: -1;
    background: radial-gradient(130% 100% at 28% 50%, rgba(5, 11, 22, .74), rgba(5, 11, 22, 0) 76%);
  }
  .mq-style4-root .method span {
    text-shadow: 0 1px 10px rgba(4, 10, 20, .8), 0 0 20px currentColor;
  }
  .mq-style4-root .card { max-width: 100%; padding: 22px 18px 18px; }
  .mq-style4-root .method { margin-top: 2px; font-size: 17px; gap: 8px; }
  .mq-style4-root .card-foot { font-size: 14.5px; }
  .mq-style4-root .keys {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 14px 4px;
    width: 100%;
    margin-top: clamp(26px, 4.2vh, 44px);
    overflow: visible;
  }
  .mq-style4-root .key {
    padding: 8px 6px 12px;
    gap: 0;
    flex-direction: row;
    justify-content: center;
  }
  .mq-style4-root .key svg { display: none; }
  .mq-style4-root .key + .key { border-left: 0; }
  .mq-style4-root .key:nth-child(odd) { border-right: 1px solid var(--mq-line); }
  .mq-style4-root .key::after { left: 9px; right: 9px; }
  .mq-style4-root .key b { font-size: 15px; font-weight: 600; }
  .mq-style4-root .field input:not([type="button"]):not([type="submit"]),
  .mq-style4-root .field select.mq-select { height: 50px; }
  .mq-style4-root .go { height: 52px; }
  .mq-style4-root .pair { grid-template-columns: 1fr; }
  .mq-style4-root .bottom {
    font-size: 10.5px;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    /* 与原型一致：沿用桌面 gap:14px，不再压成 8px */
  }
  .mq-style4-root .bottom-links {
    justify-content: center;
  }
}