/* ============================================================
   Let-Lab Help-Lab · Lab 入驻申请页样式
   ============================================================ */

:root {
  --royal: #0F4E9B;
  --royal-dark: #0B3A75;
  --royal-deep: #072A57;
  --cyan: #0891B2;
  --cyan-light: #22D3EE;
  --gold: #F59E0B;
  --ink: #101828;
  --ink-soft: #475467;
  --gray-bg: #F8FAFC;
  --gray-line: #E4E7EC;
  --white: #FFFFFF;
  --danger: #DC2626;
  --success: #067647;
  --radius: 14px;
  --shadow: 0 12px 40px rgba(7, 42, 87, .10);
  --font-cn: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-en: 'Inter', 'Helvetica Neue', sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: var(--font-cn); color: var(--ink); background: var(--gray-bg); line-height: 1.7; -webkit-font-smoothing: antialiased; }
a { text-decoration: none; color: inherit; }

/* ---------- 顶部条 ---------- */
.topbar {
  background: var(--white);
  border-bottom: 1px solid var(--gray-line);
  padding: 12px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
}
.topbar-brand { display: flex; align-items: center; gap: 12px; }
.topbar-logo { width: 44px; height: 44px; object-fit: contain; }
.topbar-brand strong { font-family: var(--font-en); font-size: 17px; color: var(--royal-dark); }
.topbar-brand strong em { font-style: normal; color: var(--cyan); }
.topbar-brand small { display: block; font-size: 11px; color: var(--ink-soft); }
.topbar-back { font-size: 14px; color: var(--royal); font-weight: 600; padding: 8px 14px; border-radius: 8px; transition: background .2s; }
.topbar-back:hover { background: rgba(15,78,155,.08); }

/* ---------- 步骤指示 ---------- */
.stepper {
  display: flex;
  justify-content: center;
  gap: 8px;
  padding: 26px 16px 10px;
  max-width: 900px;
  margin: 0 auto;
  flex-wrap: wrap;
}
.stepper .step {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: 100px;
  font-size: 13.5px;
  font-weight: 600;
  color: var(--ink-soft);
  background: var(--white);
  border: 1.5px solid var(--gray-line);
  transition: all .25s;
}
.stepper .step span {
  width: 24px; height: 24px;
  display: grid; place-items: center;
  border-radius: 50%;
  background: var(--gray-line);
  color: var(--ink-soft);
  font-size: 12.5px;
  font-weight: 700;
}
.stepper .step.active { border-color: var(--royal); color: var(--royal); background: rgba(15,78,155,.05); }
.stepper .step.active span { background: var(--royal); color: var(--white); }
.stepper .step.done { border-color: var(--cyan); color: var(--cyan); }
.stepper .step.done span { background: var(--cyan); color: var(--white); }

/* ---------- 表单主体 ---------- */
.apply-main { max-width: 860px; margin: 18px auto 60px; padding: 0 20px; }
.apply-form {
  background: var(--white);
  border: 1px solid var(--gray-line);
  border-radius: 20px;
  box-shadow: var(--shadow);
  overflow: hidden;
}
.form-step { display: none; padding: 36px 38px; }
.form-step.active { display: block; animation: fadeIn .3s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: none; } }

.step-head { margin-bottom: 26px; }
.step-head h2 { font-size: 24px; font-weight: 800; color: var(--ink); margin-bottom: 6px; letter-spacing: -0.5px; }
.step-head p { font-size: 14px; color: var(--ink-soft); }
.revenue-note {
  margin-top: 14px;
  background: rgba(15,78,155,.06);
  border: 1px solid rgba(15,78,155,.18);
  border-left: 4px solid var(--royal);
  border-radius: 10px;
  padding: 12px 16px;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.revenue-note strong { font-size: 14px; font-weight: 700; color: var(--royal); }
.revenue-note span { font-size: 13.5px; color: var(--ink-soft); }
.revenue-note b { color: var(--success); font-weight: 700; }

.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { display: flex; flex-direction: column; gap: 6px; }
.field.full { grid-column: 1 / -1; }
.field label { font-size: 14px; font-weight: 600; color: var(--ink); }
.field .hint { font-weight: 400; color: var(--ink-soft); font-size: 12.5px; }
.field input, .field select, .field textarea {
  padding: 12px 14px;
  border: 1.5px solid var(--gray-line);
  border-radius: 10px;
  font-family: var(--font-cn);
  font-size: 15px;
  color: var(--ink);
  background: var(--white);
  transition: border-color .2s, box-shadow .2s;
  width: 100%;
}
.field textarea { resize: vertical; min-height: 76px; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: none;
  border-color: var(--royal);
  box-shadow: 0 0 0 4px rgba(15,78,155,.1);
}
.field input.invalid, .field select.invalid, .field textarea.invalid { border-color: var(--danger); }

.field .check { display: flex; align-items: flex-start; gap: 10px; font-weight: 500; font-size: 14px; cursor: pointer; line-height: 1.6; }
.check input { width: 18px; height: 18px; margin-top: 3px; accent-color: var(--royal); flex-shrink: 0; }

/* ---------- 文件上传 ---------- */
.file-drop {
  border: 2px dashed var(--gray-line);
  border-radius: 14px;
  padding: 32px 20px;
  text-align: center;
  cursor: pointer;
  transition: all .25s;
  background: var(--gray-bg);
}
.file-drop:hover, .file-drop.drag { border-color: var(--royal); background: rgba(15,78,155,.05); }
.fd-ico { font-size: 34px; display: block; margin-bottom: 8px; }
.fd-title { font-size: 15px; font-weight: 600; color: var(--ink); }
.fd-sub { font-size: 12.5px; color: var(--ink-soft); margin-top: 4px; }
.file-name { margin-top: 10px; font-size: 13.5px; color: var(--success); display: none; }
.file-name.show { display: block; }
.file-name.bad { color: var(--danger); }

/* ---------- 步骤导航 ---------- */
.step-nav { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-top: 30px; padding-top: 22px; border-top: 1px solid var(--gray-line); }
.btn-next, .btn-submit {
  background: var(--royal);
  color: var(--white);
  border: none;
  padding: 13px 28px;
  border-radius: 10px;
  font-size: 15px;
  font-weight: 600;
  font-family: var(--font-cn);
  cursor: pointer;
  transition: all .25s;
}
.btn-next:hover, .btn-submit:hover { background: var(--royal-dark); transform: translateY(-2px); box-shadow: 0 8px 20px rgba(15,78,155,.3); }
.btn-prev {
  background: transparent;
  color: var(--ink-soft);
  border: 1.5px solid var(--gray-line);
  padding: 13px 24px;
  border-radius: 10px;
  font-size: 14.5px;
  font-weight: 600;
  font-family: var(--font-cn);
  cursor: pointer;
  transition: all .2s;
}
.btn-prev:hover { border-color: var(--royal); color: var(--royal); }
.btn-submit:disabled { opacity: .6; cursor: not-allowed; transform: none; }
.submit-note { margin-top: 16px; font-size: 14px; color: var(--ink-soft); text-align: center; }
.submit-note.error { color: var(--danger); }

/* ---------- 成功弹层 ---------- */
.modal {
  position: fixed;
  inset: 0;
  z-index: 500;
  background: rgba(7,42,87,.55);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}
.modal-box {
  background: var(--white);
  border-radius: 20px;
  padding: 44px 40px;
  max-width: 460px;
  text-align: center;
  box-shadow: 0 30px 80px rgba(7,42,87,.35);
  animation: popIn .35s ease;
}
@keyframes popIn { from { opacity: 0; transform: scale(.92); } to { opacity: 1; transform: scale(1); } }
.modal-ico { font-size: 52px; display: block; margin-bottom: 14px; }
.modal-box h2 { font-size: 24px; font-weight: 800; color: var(--ink); margin-bottom: 10px; }
.modal-box p { font-size: 15px; color: var(--ink-soft); }
.modal-box .modal-sub { font-size: 13.5px; margin-top: 10px; }
.modal-actions { display: flex; gap: 12px; justify-content: center; margin-top: 26px; }
.modal-actions a { padding: 11px 22px; border-radius: 10px; font-size: 14px; font-weight: 600; }
.btn-primary { background: var(--royal); color: var(--white); }
.btn-primary:hover { background: var(--royal-dark); }
.btn-ghost { border: 1.5px solid var(--gray-line); color: var(--ink-soft); }
.btn-ghost:hover { border-color: var(--royal); color: var(--royal); }

/* ---------- 响应式 ---------- */
@media (max-width: 720px) {
  .form-grid { grid-template-columns: 1fr; }
  .form-step { padding: 26px 22px; }
  .stepper { gap: 6px; }
  .stepper .step { font-size: 12px; padding: 6px 10px; }
  .step-nav { flex-wrap: wrap; }
}