/* ============================================================
   Design Tokens
   ============================================================ */
:root {
    /* Colors */
    --color-primary: #2563eb;
    --color-primary-hover: #1d4ed8;
    --color-success: #16a34a;
    --color-warning: #d97706;
    --color-error: #dc2626;

    --color-bg: #f8f9fa;
    --color-surface: #ffffff;
    --color-surface-alt: #f3f4f6;

    --color-border: #e5e7eb;
    --color-border-strong: #d1d5db;

    --color-text-primary: #111827;
    --color-text-secondary: #6b7280;
    --color-text-tertiary: #9ca3af;
    --color-text-on-primary: #ffffff;

    /* Typography */
    --text-xs: 12px;
    --text-sm: 14px;
    --text-base: 16px;
    --text-lg: 20px;
    --text-xl: 24px;
    --text-2xl: 32px;

    --fw-regular: 400;
    --fw-semibold: 600;

    --lh-body: 1.5;
    --lh-heading: 1.25;

    /* Spacing */
    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-6: 24px;
    --space-8: 32px;
    --space-12: 48px;
    --space-16: 64px;

    /* Radius */
    --radius-sm: 6px;
    --radius-md: 8px;

    /* Shadow */
    --shadow-1: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-2: 0 4px 12px rgba(0,0,0,0.10);
}

/* ============================================================
   Reset
   ============================================================ */
* { margin: 0; padding: 0; box-sizing: border-box; }
html, body { height: 100%; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
    font-size: var(--text-sm);
    line-height: var(--lh-body);
    color: var(--color-text-primary);
    background: var(--color-bg);
    -webkit-font-smoothing: antialiased;
}
a { color: var(--color-primary); text-decoration: none; }
a:hover { color: var(--color-primary-hover); }

/* ============================================================
   Typography
   ============================================================ */
.text-xs { font-size: var(--text-xs); }
.text-sm { font-size: var(--text-sm); }
.text-base { font-size: var(--text-base); }
.text-lg { font-size: var(--text-lg); }
.text-xl { font-size: var(--text-xl); }
.text-2xl { font-size: var(--text-2xl); }

.text-secondary { color: var(--color-text-secondary); }
.text-tertiary { color: var(--color-text-tertiary); }
.text-success { color: var(--color-success); }
.text-error { color: var(--color-error); }

h1, h2, h3, h4 { font-weight: var(--fw-semibold); line-height: var(--lh-heading); }
h1 { font-size: var(--text-2xl); }
h2 { font-size: var(--text-xl); }
h3 { font-size: var(--text-lg); }
h4 { font-size: var(--text-base); }

/* ============================================================
   Card
   ============================================================ */
.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-6);
}
.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding-bottom: var(--space-4);
    margin-bottom: var(--space-6);
    border-bottom: 1px solid var(--color-border);
}
.card-header h3 { font-size: var(--text-base); font-weight: var(--fw-semibold); }

/* ============================================================
   Button
   ============================================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    height: 36px;
    padding: 0 var(--space-4);
    font-size: var(--text-sm);
    font-weight: var(--fw-regular);
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background-color .15s, border-color .15s, color .15s;
    text-decoration: none;
    line-height: 1;
}
.btn-primary { background: var(--color-primary); color: var(--color-text-on-primary); }
.btn-primary:hover { background: var(--color-primary-hover); color: var(--color-text-on-primary); }

.btn-secondary {
    background: var(--color-surface);
    color: var(--color-text-primary);
    border-color: var(--color-border-strong);
}
.btn-secondary:hover { background: var(--color-surface-alt); color: var(--color-text-primary); }

.btn-danger { background: var(--color-error); color: var(--color-text-on-primary); }
.btn-danger:hover { background: #b91c1c; color: var(--color-text-on-primary); }

.btn-ghost { background: transparent; color: var(--color-text-secondary); }
.btn-ghost:hover { background: var(--color-surface-alt); color: var(--color-text-primary); }

.btn-sm { height: 28px; padding: 0 var(--space-3); font-size: var(--text-xs); }
.btn-block { width: 100%; }
.btn:disabled { background: var(--color-border); color: var(--color-text-tertiary); cursor: not-allowed; border-color: var(--color-border); }

/* ============================================================
   Form
   ============================================================ */
.form-group { margin-bottom: var(--space-4); }
.form-label {
    display: block;
    margin-bottom: var(--space-2);
    font-size: var(--text-sm);
    color: var(--color-text-primary);
}
.form-input, .form-select {
    width: 100%;
    height: 36px;
    padding: 0 var(--space-3);
    font-size: var(--text-sm);
    color: var(--color-text-primary);
    background: var(--color-surface);
    border: 1px solid var(--color-border-strong);
    border-radius: var(--radius-sm);
    outline: none;
    transition: border-color .15s;
}
.form-input:focus, .form-select:focus {
    border-color: var(--color-primary);
    outline: 2px solid rgba(37, 99, 235, 0.15);
}
.form-hint {
    margin-top: var(--space-1);
    font-size: var(--text-xs);
    color: var(--color-text-tertiary);
}

/* ============================================================
   Table
   ============================================================ */
.table { width: 100%; border-collapse: collapse; }
.table th, .table td {
    padding: var(--space-3) var(--space-4);
    text-align: left;
    font-size: var(--text-sm);
    border-bottom: 1px solid var(--color-border);
}
.table th {
    font-weight: var(--fw-semibold);
    color: var(--color-text-secondary);
    background: var(--color-surface-alt);
}
.table tbody tr:hover { background: var(--color-surface-alt); }

/* ============================================================
   Badge
   ============================================================ */
.badge {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-2);
    font-size: var(--text-xs);
    border-radius: var(--radius-sm);
    font-weight: var(--fw-semibold);
}
.badge-success { background: #dcfce7; color: var(--color-success); }
.badge-error { background: #fee2e2; color: var(--color-error); }

/* ============================================================
   Alert
   ============================================================ */
.alert {
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-sm);
    font-size: var(--text-sm);
    margin-bottom: var(--space-4);
}
.alert-error { background: #fee2e2; color: var(--color-error); }
.alert-success { background: #dcfce7; color: var(--color-success); }

/* ============================================================
   Auth Layout (login pages)
   ============================================================ */
.auth-wrap {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-4);
}
.auth-card {
    width: 100%;
    max-width: 400px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-8);
}
.auth-card h1 {
    font-size: var(--text-xl);
    margin-bottom: var(--space-2);
    text-align: center;
}
.auth-card .auth-subtitle {
    text-align: center;
    color: var(--color-text-secondary);
    margin-bottom: var(--space-6);
}

.slider-captcha { position: relative; width: 100%; height: 40px; background: var(--color-surface-alt); border: 1px solid var(--color-border-strong); border-radius: var(--radius-sm); user-select: none; overflow: hidden; touch-action: none; }
.slider-captcha .slider-track { position: absolute; top: 0; left: 0; height: 100%; background: #d1fae5; border-radius: var(--radius-sm); transition: none; }
.slider-captcha .slider-text { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; font-size: var(--text-xs); color: var(--color-text-tertiary); pointer-events: none; }
.slider-captcha .slider-thumb { position: absolute; top: 0; left: 0; width: 40px; height: 40px; background: #ffffff; border: 1px solid var(--color-border-strong); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; cursor: grab; z-index: 2; transition: none; }
.slider-captcha .slider-thumb:active { cursor: grabbing; }
.slider-captcha .slider-thumb svg { width: 18px; height: 18px; color: var(--color-text-secondary); }
.slider-captcha.success { border-color: var(--color-success); }
.slider-captcha.success .slider-track { background: #a7f3d0; }
.slider-captcha.success .slider-thumb { background: var(--color-success); border-color: var(--color-success); }
.slider-captcha.success .slider-thumb svg { color: #ffffff; }
.slider-captcha.success .slider-text { color: #065f46; }

.form-checkbox { display: flex; align-items: center; gap: var(--space-3); cursor: pointer; font-size: var(--text-sm); color: var(--color-text-secondary); }
.form-checkbox input[type="checkbox"] { position: absolute; opacity: 0; width: 0; height: 0; }
.form-checkbox-check { width: 18px; height: 18px; border: 1.5px solid var(--color-border-strong); border-radius: 4px; display: inline-flex; align-items: center; justify-content: center; transition: all 0.2s ease; flex-shrink: 0; }
.form-checkbox input[type="checkbox"]:checked + .form-checkbox-check { background: var(--color-primary); border-color: var(--color-primary); }
.form-checkbox input[type="checkbox"]:checked + .form-checkbox-check::after { content: '\2713'; color: #ffffff; font-size: 12px; font-weight: bold; line-height: 1; }
.form-checkbox input[type="checkbox"]:focus + .form-checkbox-check { outline: 2px solid var(--color-primary); outline-offset: 2px; }

/* ============================================================
   Admin Layout (sidebar + topbar)
   ============================================================ */
.layout { display: flex; min-height: 100vh; }

.sidebar {
    width: 220px;
    flex-shrink: 0;
    background: var(--color-surface);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
}
.sidebar-brand {
    height: 56px;
    display: flex;
    align-items: center;
    padding: 0 var(--space-6);
    font-size: var(--text-base);
    font-weight: var(--fw-semibold);
    color: var(--color-text-primary);
    border-bottom: 1px solid var(--color-border);
}
.sidebar-nav {
    flex: 1;
    padding: var(--space-4) var(--space-3);
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
}
.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    height: 36px;
    padding: 0 var(--space-3);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    border-radius: var(--radius-sm);
    text-decoration: none;
    transition: background-color .15s, color .15s;
}
.nav-item:hover {
    background: var(--color-surface-alt);
    color: var(--color-text-primary);
}
.nav-item.active {
    background: var(--color-surface-alt);
    color: var(--color-primary);
    font-weight: var(--fw-semibold);
}
.nav-item .icon { color: currentColor; }

.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.topbar {
    height: 56px;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 var(--space-6);
}
.topbar-title { font-size: var(--text-base); font-weight: var(--fw-semibold); }
.topbar-user {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
}
.topbar-user .user-name { color: var(--color-text-primary); }
.content { flex: 1; padding: var(--space-6); }

/* Stat cards */
.stat-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-4); }
.stat-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-6);
}
.stat-label { font-size: var(--text-sm); color: var(--color-text-secondary); }
.stat-value { font-size: var(--text-2xl); font-weight: var(--fw-semibold); margin-top: var(--space-2); }

/* Toolbar */
.toolbar { display: flex; align-items: center; justify-content: space-between; margin-bottom: var(--space-4); }
.toolbar h2 { font-size: var(--text-lg); }

/* Narrow form */
.form-narrow { max-width: 420px; }

/* ============================================================
   Install Layout
   ============================================================ */
.install-wrap {
    min-height: 100vh;
    padding: var(--space-8) var(--space-4);
    display: flex;
    align-items: flex-start;
    justify-content: center;
}
.install-card {
    width: 100%;
    max-width: 640px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
}
.install-header {
    padding: var(--space-6) var(--space-8);
    border-bottom: 1px solid var(--color-border);
}
.install-header h1 {
    font-size: var(--text-xl);
    margin-bottom: var(--space-1);
}
.install-header p { color: var(--color-text-secondary); font-size: var(--text-sm); }

.install-body { padding: var(--space-8); }
.install-footer {
    padding: var(--space-4) var(--space-8);
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--color-surface-alt);
    border-bottom-left-radius: var(--radius-md);
    border-bottom-right-radius: var(--radius-md);
}

/* Stepper */
.stepper {
    display: flex;
    align-items: center;
    padding: var(--space-6) var(--space-8);
    background: var(--color-surface-alt);
    border-bottom: 1px solid var(--color-border);
    gap: var(--space-3);
}
.step {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--color-text-tertiary);
    flex-shrink: 0;
}
.step-num {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--color-surface);
    border: 1px solid var(--color-border-strong);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-xs);
    font-weight: var(--fw-semibold);
    flex-shrink: 0;
}
.step.active { color: var(--color-primary); font-weight: var(--fw-semibold); }
.step.active .step-num {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-text-on-primary);
}
.step.done { color: var(--color-success); }
.step.done .step-num {
    background: var(--color-success);
    border-color: var(--color-success);
    color: var(--color-text-on-primary);
}
.step-sep { flex: 1; height: 1px; background: var(--color-border-strong); }

/* Check list */
.check-list { list-style: none; }
.check-list li {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-3) 0;
    border-bottom: 1px solid var(--color-border);
    font-size: var(--text-sm);
}
.check-list li:last-child { border-bottom: none; }
.check-list .check-name { color: var(--color-text-primary); }
.check-list .check-value {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-text-secondary);
}

/* Install section title */
.section-title {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    margin-bottom: var(--space-4);
    padding-bottom: var(--space-2);
    border-bottom: 1px solid var(--color-border);
}

/* Done state */
.done-state {
    text-align: center;
    padding: var(--space-8) 0;
}
.done-state .done-icon {
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: #dcfce7;
    color: var(--color-success);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--space-4);
}
.done-state h2 { font-size: var(--text-lg); margin-bottom: var(--space-2); }
.done-state p { color: var(--color-text-secondary); margin-bottom: var(--space-6); }

/* ============================================================
   Utility
   ============================================================ */
.flex { display: flex; }
.flex-between { display: flex; align-items: center; justify-content: space-between; }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.mt-2 { margin-top: var(--space-2); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

/* Icon */
.icon { width: 16px; height: 16px; stroke-width: 2; flex-shrink: 0; }
.icon-lg { width: 20px; height: 20px; }