/* 专业技能智能考试系统 - 全局样式 */
:root {
    --primary: #4f46e5;
    --primary-light: #6366f1;
    --primary-dark: #3730a3;
    --secondary: #0ea5e9;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #6366f1;
    --dark: #1e293b;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-500: #64748b;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
    --shadow: 0 1px 3px rgba(0,0,0,.08), 0 4px 12px rgba(0,0,0,.04);
    --shadow-md: 0 4px 6px rgba(0,0,0,.05), 0 10px 24px rgba(0,0,0,.08);
    --shadow-lg: 0 10px 40px rgba(0,0,0,.12);
    --transition: all .25s cubic-bezier(.4,0,.2,1);
}

* { margin: 0; padding: 0; box-sizing: border-box; }
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", "Microsoft YaHei", sans-serif; background: var(--gray-50); color: var(--gray-800); line-height: 1.6; -webkit-font-smoothing: antialiased; }
a { color: var(--primary); text-decoration: none; transition: var(--transition); }
a:hover { color: var(--primary-dark); }

/* Layout */
.app-layout { display: flex; min-height: 100vh; }
.sidebar { width: 260px; background: linear-gradient(180deg, var(--gray-900) 0%, var(--gray-800) 100%); color: #fff; position: fixed; top: 0; left: 0; bottom: 0; z-index: 200; display: flex; flex-direction: column; overflow-y: auto; }
.sidebar-brand { padding: 24px 20px 20px; border-bottom: 1px solid rgba(255,255,255,.08); }
.sidebar-brand h1 { font-size: 17px; font-weight: 700; letter-spacing: .5px; }
.sidebar-brand p { font-size: 11px; color: rgba(255,255,255,.45); margin-top: 4px; }
.sidebar-nav { flex: 1; padding: 12px 0; }
.sidebar-nav a { display: flex; align-items: center; gap: 12px; padding: 11px 20px; color: rgba(255,255,255,.6); font-size: 14px; transition: var(--transition); border-left: 3px solid transparent; }
.sidebar-nav a:hover { color: #fff; background: rgba(255,255,255,.06); }
.sidebar-nav a.active { color: #fff; background: rgba(79,70,229,.25); border-left-color: var(--primary-light); }
.sidebar-nav a .nav-icon { width: 20px; text-align: center; font-size: 16px; flex-shrink: 0; }
.sidebar-footer { padding: 16px 20px; border-top: 1px solid rgba(255,255,255,.08); font-size: 12px; color: rgba(255,255,255,.35); }

.main-area { flex: 1; margin-left: 260px; display: flex; flex-direction: column; min-height: 100vh; }
.topbar { background: #fff; padding: 0 32px; height: 64px; display: flex; align-items: center; justify-content: space-between; border-bottom: 1px solid var(--gray-200); position: sticky; top: 0; z-index: 100; }
.topbar h2 { font-size: 18px; font-weight: 600; color: var(--gray-900); }
.topbar-right { display: flex; align-items: center; gap: 16px; }
.topbar-user { display: flex; align-items: center; gap: 10px; font-size: 14px; color: var(--gray-600); }
.topbar-avatar { width: 36px; height: 36px; border-radius: 50%; background: linear-gradient(135deg, var(--primary), var(--secondary)); color: #fff; display: flex; align-items: center; justify-content: center; font-size: 14px; font-weight: 600; }

.content { flex: 1; padding: 28px 32px; }

/* Cards */
.card { background: #fff; border-radius: var(--radius); border: 1px solid var(--gray-200); box-shadow: var(--shadow); overflow: hidden; }
.card-header { padding: 18px 24px; border-bottom: 1px solid var(--gray-100); display: flex; align-items: center; justify-content: space-between; }
.card-header h3 { font-size: 16px; font-weight: 600; color: var(--gray-900); }
.card-body { padding: 24px; }

/* Stats */
.stats-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 20px; margin-bottom: 28px; }
.stat-card { background: #fff; border-radius: var(--radius); padding: 24px; border: 1px solid var(--gray-200); box-shadow: var(--shadow); display: flex; align-items: center; gap: 16px; transition: var(--transition); }
.stat-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.stat-icon { width: 52px; height: 52px; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; font-size: 24px; }
.stat-icon.blue { background: #eef2ff; }
.stat-icon.green { background: #ecfdf5; }
.stat-icon.orange { background: #fffbeb; }
.stat-icon.purple { background: #f5f3ff; }
.stat-icon.red { background: #fef2f2; }
.stat-icon.cyan { background: #ecfeff; }
.stat-info .stat-value { font-size: 28px; font-weight: 700; color: var(--gray-900); line-height: 1.2; }
.stat-info .stat-label { font-size: 13px; color: var(--gray-500); margin-top: 2px; }

/* Buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 9px 20px; border-radius: var(--radius-sm); font-size: 14px; font-weight: 500; border: none; cursor: pointer; transition: var(--transition); text-decoration: none; line-height: 1.4; }
.btn-sm { padding: 6px 14px; font-size: 13px; }
.btn-lg { padding: 12px 28px; font-size: 15px; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); color: #fff; box-shadow: 0 4px 12px rgba(79,70,229,.3); }
.btn-success { background: var(--success); color: #fff; }
.btn-success:hover { background: #059669; color: #fff; }
.btn-warning { background: var(--warning); color: #fff; }
.btn-warning:hover { background: #d97706; color: #fff; }
.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { background: #dc2626; color: #fff; }
.btn-outline { background: transparent; color: var(--primary); border: 1.5px solid var(--gray-300); }
.btn-outline:hover { border-color: var(--primary); background: #eef2ff; color: var(--primary); }
.btn-ghost { background: transparent; color: var(--gray-600); }
.btn-ghost:hover { background: var(--gray-100); color: var(--gray-900); }
.btn-block { width: 100%; }

/* Forms */
.form-group { margin-bottom: 20px; }
.form-label { display: block; font-size: 14px; font-weight: 500; color: var(--gray-700); margin-bottom: 6px; }
.form-input, .form-select, .form-textarea { width: 100%; padding: 10px 14px; border: 1.5px solid var(--gray-300); border-radius: var(--radius-sm); font-size: 14px; color: var(--gray-800); background: #fff; transition: var(--transition); font-family: inherit; }
.form-input:focus, .form-select:focus, .form-textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(79,70,229,.1); }
.form-textarea { min-height: 100px; resize: vertical; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.form-row-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 16px; }
.form-hint { font-size: 12px; color: var(--gray-400); margin-top: 4px; }

/* Table */
.table-wrap { overflow-x: auto; }
table.data-table { width: 100%; border-collapse: collapse; font-size: 14px; }
table.data-table th { background: var(--gray-50); padding: 12px 16px; text-align: left; font-weight: 600; color: var(--gray-600); font-size: 12px; text-transform: uppercase; letter-spacing: .5px; border-bottom: 1px solid var(--gray-200); }
table.data-table td { padding: 14px 16px; border-bottom: 1px solid var(--gray-100); color: var(--gray-700); }
table.data-table tr:hover td { background: var(--gray-50); }
table.data-table tr:last-child td { border-bottom: none; }

/* Badges */
.badge { display: inline-flex; align-items: center; padding: 3px 10px; border-radius: 20px; font-size: 12px; font-weight: 500; }
.badge-draft { background: var(--gray-100); color: var(--gray-500); }
.badge-pending { background: #fffbeb; color: #b45309; }
.badge-active { background: #ecfdf5; color: #047857; }
.badge-ended { background: var(--gray-100); color: var(--gray-500); }
.badge-closed { background: #fef2f2; color: #b91c1c; }
.badge-success { background: #ecfdf5; color: #047857; }
.badge-danger { background: #fef2f2; color: #b91c1c; }
.badge-warning { background: #fffbeb; color: #b45309; }
.badge-info { background: #eef2ff; color: #4338ca; }
.badge-primary { background: var(--primary); color: #fff; }

/* Alert */
.alert { padding: 14px 18px; border-radius: var(--radius-sm); margin-bottom: 20px; font-size: 14px; display: flex; align-items: center; gap: 10px; }
.alert-success { background: #ecfdf5; color: #065f46; border: 1px solid #a7f3d0; }
.alert-error { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-warning { background: #fffbeb; color: #92400e; border: 1px solid #fde68a; }
.alert-info { background: #eef2ff; color: #3730a3; border: 1px solid #c7d2fe; }

/* Empty */
.empty-state { text-align: center; padding: 60px 20px; color: var(--gray-400); }
.empty-state .empty-icon { font-size: 56px; margin-bottom: 16px; opacity: .5; }
.empty-state p { font-size: 15px; }

/* Page Header */
.page-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 24px; }
.page-header h2 { font-size: 22px; font-weight: 700; color: var(--gray-900); }

/* Grid */
.grid-2 { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }

/* Login Page */
.login-page { min-height: 100vh; display: flex; align-items: center; justify-content: center; background: linear-gradient(135deg, #1e1b4b 0%, #312e81 40%, #4338ca 100%); position: relative; overflow: hidden; }
.login-page::before { content: ''; position: absolute; width: 600px; height: 600px; border-radius: 50%; background: radial-gradient(circle, rgba(99,102,241,.15) 0%, transparent 70%); top: -200px; right: -100px; }
.login-page::after { content: ''; position: absolute; width: 400px; height: 400px; border-radius: 50%; background: radial-gradient(circle, rgba(14,165,233,.1) 0%, transparent 70%); bottom: -100px; left: -50px; }
.login-card { background: rgba(255,255,255,.97); border-radius: 20px; padding: 48px 40px; width: 440px; max-width: 92%; box-shadow: 0 25px 60px rgba(0,0,0,.3); position: relative; z-index: 1; }
.login-card .login-logo { text-align: center; margin-bottom: 36px; }
.login-card .login-logo .logo-icon { width: 64px; height: 64px; border-radius: 16px; background: linear-gradient(135deg, var(--primary), var(--secondary)); display: inline-flex; align-items: center; justify-content: center; font-size: 28px; color: #fff; margin-bottom: 16px; }
.login-card .login-logo h1 { font-size: 24px; font-weight: 700; color: var(--gray-900); }
.login-card .login-logo p { font-size: 14px; color: var(--gray-500); margin-top: 6px; }

/* Exam Cards (Student) */
.exam-card { background: #fff; border-radius: var(--radius); border: 1px solid var(--gray-200); padding: 24px; transition: var(--transition); position: relative; overflow: hidden; }
.exam-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--primary-light); }
.exam-card .exam-type-tag { position: absolute; top: 16px; right: 16px; padding: 4px 12px; border-radius: 20px; font-size: 12px; font-weight: 600; }
.exam-type-theory { background: #eef2ff; color: #4338ca; }
.exam-type-practical { background: #ecfdf5; color: #047857; }

/* Progress Bar */
.progress-bar { height: 6px; background: var(--gray-200); border-radius: 3px; overflow: hidden; }
.progress-bar .progress-fill { height: 100%; background: linear-gradient(90deg, var(--primary), var(--secondary)); border-radius: 3px; transition: width .4s ease; }

/* Timer */
.timer-display { font-size: 20px; font-weight: 700; color: var(--primary); font-variant-numeric: tabular-nums; }
.timer-display.warning { color: var(--danger); animation: timerPulse 1s infinite; }
@keyframes timerPulse { 0%,100% { opacity: 1; } 50% { opacity: .5; } }

/* Face Verification */
.face-verify-box { width: 320px; height: 240px; border-radius: var(--radius); background: var(--gray-100); border: 2px dashed var(--gray-300); display: flex; align-items: center; justify-content: center; margin: 0 auto 24px; position: relative; overflow: hidden; }
.face-verify-box video { width: 100%; height: 100%; object-fit: cover; }
.face-verify-box .face-overlay { position: absolute; top: 50%; left: 50%; transform: translate(-50%,-50%); width: 180px; height: 180px; border: 3px solid rgba(79,70,229,.5); border-radius: 50%; }

/* Responsive */
@media (max-width: 1024px) {
    .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); }
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
    .sidebar { display: none; }
    .main-area { margin-left: 0; }
    .content { padding: 20px 16px; }
    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .form-row, .form-row-3 { grid-template-columns: 1fr; }
    .stats-grid { grid-template-columns: 1fr; }
    .topbar { padding: 0 16px; }
}