/* ===== 云涌世纪 · AI 基本功考试 设计系统 ===== */
:root {
  --primary: #1b66f0;
  --primary-dark: #0e3ea8;
  --primary-light: #63c0f5;
  --navy: #0a1f44;
  --navy-2: #122c5e;
  --bg: #f3f6fc;
  --card: #ffffff;
  --border: #e3e9f4;
  --text: #1c2434;
  --muted: #64748b;
  --ok: #16a34a;
  --bad: #dc2626;
  --warn: #d97706;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(16, 42, 100, 0.06), 0 6px 24px rgba(16, 42, 100, 0.05);
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-text-size-adjust: 100%; }
body {
  font-family: -apple-system, "PingFang SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  background: var(--bg); color: var(--text); line-height: 1.65; font-size: 15px;
}
.container { max-width: 880px; margin: 0 auto; padding: 28px 20px; }
h1 { font-size: 22px; font-weight: 700; }
h2 { font-size: 17px; font-weight: 600; margin-bottom: 12px; }
.muted { color: var(--muted); font-size: 13px; }
a { color: var(--primary); text-decoration: none; }

/* ---- 卡片 ---- */
.card {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 22px; margin-bottom: 16px;
  box-shadow: var(--shadow);
}

/* ---- 按钮 ---- */
button {
  background: var(--primary); color: #fff; border: none; border-radius: 10px;
  padding: 10px 20px; font-size: 14px; font-weight: 500; cursor: pointer;
  font-family: inherit; transition: all 0.15s ease;
}
button:hover { background: var(--primary-dark); }
button:active { transform: scale(0.98); }
button.secondary {
  background: #fff; color: var(--text); border: 1px solid var(--border);
}
button.secondary:hover { border-color: var(--primary); color: var(--primary); background: #fff; }
button.ghost { background: transparent; color: var(--muted); }
button.ghost:hover { background: rgba(27, 102, 240, 0.06); color: var(--primary); }
button.danger { background: var(--bad); }
button.danger:hover { background: #b91c1c; }
button:disabled { background: #cbd5e1; color: #fff; cursor: not-allowed; transform: none; }

/* ---- 表单 ---- */
input, select, textarea {
  width: 100%; padding: 11px 14px; border: 1.5px solid var(--border); border-radius: 10px;
  font-size: 14px; margin-bottom: 12px; font-family: inherit; background: #fff;
  transition: border-color 0.15s; color: var(--text);
}
input:focus, select:focus, textarea:focus {
  outline: none; border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(27, 102, 240, 0.12);
}
textarea { min-height: 130px; resize: vertical; line-height: 1.7; }

/* ---- 布局辅助 ---- */
.row { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; }
.spread { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }

/* ---- 顶栏 ---- */
.topbar {
  background: #fff; border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 40;
}
.topbar-inner {
  max-width: 880px; margin: 0 auto; padding: 12px 20px;
  display: flex; justify-content: space-between; align-items: center; gap: 12px;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand img { height: 30px; }
.brand .brand-name { font-weight: 700; font-size: 15px; color: var(--navy); }
.brand .brand-sub { font-size: 12px; color: var(--muted); }

/* ---- 徽标 ---- */
.badge {
  display: inline-block; padding: 3px 10px; border-radius: 20px;
  font-size: 12px; font-weight: 500; background: #e8f1ff; color: var(--primary);
}
.badge.warn { background: #fef3c7; color: var(--warn); }
.badge.ok { background: #dcfce7; color: var(--ok); }
.badge.bad { background: #fee2e2; color: var(--bad); }

/* ---- 表格 ---- */
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { text-align: left; padding: 10px 8px; border-bottom: 1px solid var(--border); }
th { color: var(--muted); font-weight: 500; font-size: 13px; }
tr:last-child td { border-bottom: none; }
.correct { color: var(--ok); }
.wrong { color: var(--bad); }
.hidden { display: none !important; }

/* ===== 登录页（左右分屏） ===== */
.login-split { display: flex; min-height: 100vh; }
.login-brand {
  flex: 1.1; background: linear-gradient(150deg, var(--navy) 0%, var(--navy-2) 55%, var(--primary-dark) 100%);
  color: #fff; display: flex; flex-direction: column; justify-content: center;
  padding: 60px 56px; position: relative; overflow: hidden;
}
.login-brand::after {
  content: ""; position: absolute; right: -120px; bottom: -120px; width: 380px; height: 380px;
  border-radius: 50%; background: radial-gradient(circle, rgba(99,192,245,0.25), transparent 70%);
}
.login-brand img.wordmark { width: 300px; max-width: 80%; margin-bottom: 28px; }
.login-brand h2 { font-size: 26px; font-weight: 700; margin-bottom: 12px; line-height: 1.4; }
.login-brand p { color: rgba(255,255,255,0.75); font-size: 14px; max-width: 380px; }
.login-form-side {
  flex: 1; display: flex; align-items: center; justify-content: center;
  padding: 40px 24px; background: var(--bg);
}
.login-box { width: 100%; max-width: 360px; }
.login-box .mark { height: 52px; margin-bottom: 18px; display: none; }
.login-box h1 { margin-bottom: 4px; }
.login-box .sub { margin-bottom: 24px; }
@media (max-width: 760px) {
  .login-brand { display: none; }
  .login-box .mark { display: block; }
}

/* ===== 考试页 ===== */
.exam-topbar {
  background: #fff; border-bottom: 1px solid var(--border);
  position: sticky; top: 0; z-index: 40;
}
.exam-topbar-inner {
  max-width: 1080px; margin: 0 auto; padding: 10px 20px;
  display: flex; align-items: center; justify-content: space-between; gap: 14px;
}
.exam-topbar .title { font-size: 15px; font-weight: 600; color: var(--navy); }
.progress-track { height: 4px; background: var(--border); }
.progress-fill {
  height: 100%; width: 0%;
  background: linear-gradient(90deg, var(--primary-light), var(--primary));
  transition: width 0.3s ease;
}
.timer-pill {
  background: var(--navy); color: #fff; padding: 6px 16px; border-radius: 20px;
  font-size: 15px; font-variant-numeric: tabular-nums; font-weight: 600;
}
.timer-pill.urgent { background: var(--bad); animation: pulse 1s infinite; }
@keyframes pulse { 50% { opacity: 0.75; } }

.exam-layout {
  max-width: 1080px; margin: 0 auto; padding: 24px 20px;
  display: grid; grid-template-columns: 220px 1fr; gap: 20px; align-items: start;
}
@media (max-width: 820px) { .exam-layout { grid-template-columns: 1fr; } }

/* 答题卡 */
.palette-card { position: sticky; top: 76px; }
.palette-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 8px; margin: 12px 0; }
.palette-btn {
  aspect-ratio: 1; padding: 0; border-radius: 8px; font-size: 13px; font-weight: 600;
  background: #fff; color: var(--muted); border: 1.5px solid var(--border);
}
.palette-btn:hover { border-color: var(--primary); color: var(--primary); background: #fff; }
.palette-btn.answered { background: #e8f1ff; color: var(--primary); border-color: #bcd6ff; }
.palette-btn.current { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(27,102,240,0.15); color: var(--primary); }
.legend { display: flex; gap: 14px; font-size: 12px; color: var(--muted); margin-bottom: 12px; }
.legend i { display: inline-block; width: 10px; height: 10px; border-radius: 3px; margin-right: 4px; }
.legend .l-a { background: #e8f1ff; border: 1px solid #bcd6ff; }
.legend .l-u { background: #fff; border: 1px solid var(--border); }

/* 题目卡（一屏一题） */
.q-card { padding: 30px 32px; }
.q-meta { display: flex; gap: 8px; align-items: center; margin-bottom: 14px; }
.q-num { font-size: 13px; font-weight: 600; color: var(--primary); }
.q-text { font-size: 18px; font-weight: 600; line-height: 1.7; margin-bottom: 22px; }
.q-text .pts { font-size: 13px; font-weight: 400; color: var(--muted); }
.option {
  display: flex; align-items: flex-start; gap: 12px; padding: 14px 16px;
  border: 1.5px solid var(--border); border-radius: 12px; margin-bottom: 10px;
  cursor: pointer; transition: all 0.12s ease; background: #fff; user-select: none;
}
.option:hover { border-color: var(--primary-light); background: #f7fbff; }
.option.selected { border-color: var(--primary); background: #e8f1ff; }
.option .key {
  flex: none; width: 26px; height: 26px; border-radius: 8px; display: flex;
  align-items: center; justify-content: center; font-size: 13px; font-weight: 600;
  background: var(--bg); color: var(--muted); margin-top: 1px;
}
.option.selected .key { background: var(--primary); color: #fff; }
.q-nav { display: flex; justify-content: space-between; margin-top: 26px; gap: 10px; }

/* 弹层 */
.overlay {
  position: fixed; inset: 0; background: rgba(10, 31, 68, 0.66);
  backdrop-filter: blur(3px); z-index: 100;
  display: flex; align-items: center; justify-content: center; padding: 20px;
}
.overlay .card { max-width: 500px; width: 100%; padding: 28px; margin: 0; }
.overlay .card h2 { font-size: 19px; }

/* ===== 成绩页 ===== */
.score-hero {
  background: linear-gradient(150deg, var(--navy) 0%, var(--navy-2) 60%, var(--primary-dark) 100%);
  color: #fff; border: none;
}
.score-hero .muted { color: rgba(255, 255, 255, 0.66); }
.score-ring {
  width: 120px; height: 120px; border-radius: 50%; flex: none;
  display: flex; align-items: center; justify-content: center;
}
.score-ring .inner {
  width: 96px; height: 96px; border-radius: 50%; background: var(--navy-2);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
}
.score-ring .num { font-size: 32px; font-weight: 700; line-height: 1.1; }
.score-ring .cap { font-size: 11px; color: rgba(255,255,255,0.6); }
.explain {
  background: #f6f9ff; border-left: 3px solid var(--primary-light);
  border-radius: 0 10px 10px 0; padding: 10px 14px; font-size: 13px; margin-top: 10px;
}

/* ===== 管理后台 ===== */
.tabs { display: flex; gap: 6px; margin-bottom: 18px; }
.tabs button { background: transparent; color: var(--muted); border-radius: 10px; padding: 8px 16px; }
.tabs button:hover { background: rgba(27,102,240,0.07); color: var(--primary); }
.tabs button.active { background: var(--navy); color: #fff; }