/* 凉风Lab 后台 · 登录页
   布局呼应 liangfenglab.com 首屏：左侧品牌陈述，右侧卡片；窄屏堆叠。 */

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: var(--font-size);
  line-height: var(--line);
  -webkit-font-smoothing: antialiased;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 24px;
}

.lf-login {
  width: 100%;
  max-width: 940px;
  display: grid;
  grid-template-columns: 1fr 400px;
  gap: 72px;
  align-items: center;
}

/* ---------- 左：品牌陈述 ---------- */
.lf-brand .lf-lockup {
  display: flex; align-items: center; gap: 10px;
  margin-bottom: 34px;
}
.lf-brand .lf-mark { width: 30px; height: 30px; color: var(--fg); flex: none; }
.lf-brand .lf-wordmark {
  font-family: var(--font-display);
  font-weight: 700; font-size: 20px; letter-spacing: .02em;
}
.lf-eyebrow {
  font-family: var(--font-mono);
  font-size: 12px; letter-spacing: .14em;
  text-transform: uppercase; color: var(--accent);
}
.lf-brand h1 {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 42px;
  line-height: 1.25;
  letter-spacing: .01em;
  margin: 16px 0 0;
}
.lf-brand .lf-lead {
  color: var(--muted);
  margin: 18px 0 0;
  max-width: 380px;
}

/* ---------- 右：登录卡片 ---------- */
.lf-card {
  background: var(--card-bg, #fff);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-2);
  padding: 30px 28px;
}
.lf-card .lf-card-title {
  font-family: var(--font-display);
  font-weight: 700; font-size: 20px;
  margin: 0 0 22px;
}

.lf-field { margin-bottom: 16px; }
.lf-label {
  display: block; font-size: 13.5px; font-weight: 500;
  margin: 0 0 6px; color: var(--fg);
}
.lf-input {
  width: 100%; min-height: 44px;
  padding: 10px 12px;
  background: var(--bg);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font: 400 var(--font-size)/1.5 var(--font-body);
  transition: border-color .15s ease, box-shadow .15s ease;
}
.lf-input::placeholder { color: var(--muted); opacity: .7; }
.lf-input:hover { border-color: var(--muted); }
.lf-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-bg);
}

/* 验证码：输入框 + 图片并排 */
.lf-captcha { display: flex; gap: 10px; }
.lf-captcha .lf-input { flex: 1; min-width: 0; }
/* 验证码原图为 250x62（5 位字符），必须保持宽高比，
   否则两端字符被裁掉导致无法辨认。 */
.lf-captcha img {
  width: 178px; height: 44px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: #fff;
  object-fit: contain;
  flex: none;
}
.lf-captcha img:hover { border-color: var(--accent); }

.lf-submit {
  width: 100%; min-height: 44px; margin-top: 6px;
  border: 1px solid transparent; border-radius: var(--radius);
  background: var(--btn-bg); color: #fff;
  font: 500 var(--font-size)/1 var(--font-body);
  cursor: pointer;
  box-shadow: var(--shadow-1);
  transition: background-color .15s ease, box-shadow .15s ease;
}
.lf-submit:hover { background: var(--btn-hover); box-shadow: var(--shadow-2); }
.lf-submit:active { background: var(--btn-active); }

.lf-foot {
  margin-top: 18px; padding-top: 16px;
  border-top: 1px dashed var(--border);
  font-family: var(--font-mono);
  font-size: 11.5px; letter-spacing: .06em;
  color: var(--muted);
  text-align: center;
}

/* ---------- 主题切换 ---------- */
.lf-theme-toggle {
  position: fixed; top: 20px; right: 20px;
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px;
  border: 1px solid var(--border); border-radius: var(--radius-sm);
  background: transparent; color: var(--muted);
  cursor: pointer; transition: all .15s ease;
}
.lf-theme-toggle:hover { color: var(--accent); border-color: var(--accent); }
.lf-theme-toggle svg { width: 16px; height: 16px; }
html[data-theme="dark"] .lf-theme-toggle .lf-icon-moon { display: none; }
html:not([data-theme="dark"]) .lf-theme-toggle .lf-icon-sun { display: none; }

/* ---------- 窄屏 ---------- */
@media (max-width: 860px) {
  .lf-login { grid-template-columns: 1fr; gap: 36px; max-width: 400px; }
  .lf-brand h1 { font-size: 32px; }
  .lf-brand .lf-lead { max-width: none; }
}