:root {
    --bg-primary: #0d1117;
    --bg-secondary: #161b22;
    --bg-tertiary: #21262d;
    --border-color: #30363d;
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --green: #3fb950;
    --red: #f85149;
    --blue: #58a6ff;
    --gold: #d4a647;
    --accent: #1f6feb;
    --hover-bg: rgba(88, 166, 255, 0.04);
    --current-row-bg: rgba(31, 111, 235, 0.08);
}

[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #f6f8fa;
    --bg-tertiary: #eef1f5;
    --border-color: #d0d7de;
    --text-primary: #1f2328;
    --text-secondary: #656d76;
    --green: #1a7f37;
    --red: #cf222e;
    --blue: #0969da;
    --gold: #9a6700;
    --accent: #0969da;
    --hover-bg: rgba(31, 111, 235, 0.04);
    --current-row-bg: rgba(31, 111, 235, 0.06);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    min-height: 100vh;
}

/* Navbar */
.navbar {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 0 24px;
    display: flex;
    align-items: center;
    height: 56px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-brand {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-right: 32px;
    white-space: nowrap;
}

.nav-links { display: flex; gap: 4px; }

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 8px 16px;
    border-radius: 6px;
    font-size: 14px;
    transition: all 0.15s;
}

.nav-links a:hover { color: var(--text-primary); background: var(--bg-tertiary); }
.nav-links a.active { color: #fff; background: var(--accent); }

.nav-right { margin-left: auto; display: flex; align-items: center; }

/* Theme Toggle */
.theme-toggle {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    width: 36px;
    height: 36px;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.15s;
}

.theme-toggle:hover { color: var(--text-primary); border-color: var(--text-secondary); }
.theme-toggle svg { width: 18px; height: 18px; }

[data-theme="light"] .icon-sun { display: none; }
[data-theme="light"] .icon-moon { display: block; }
:root .icon-sun { display: block; }
:root .icon-moon { display: none; }
body:not([data-theme="light"]) .icon-moon { display: none; }

/* Container */
.container { max-width: 1400px; margin: 0 auto; padding: 24px; }

/* Page Header */
.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    flex-wrap: wrap;
    gap: 12px;
}

.page-header h1 { font-size: 24px; font-weight: 600; }

.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.update-time {
    color: var(--text-secondary);
    font-size: 13px;
}

/* Buttons */
.btn {
    padding: 6px 16px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 13px;
    cursor: pointer;
    transition: all 0.15s;
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn:hover { border-color: var(--text-secondary); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-primary:hover { background: #388bfd; }
.btn-secondary { background: var(--bg-tertiary); }

/* Section */
.section {
    margin-bottom: 32px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.section-title {
    font-size: 16px;
    font-weight: 600;
    padding: 12px 16px;
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 8px;
}

.badge {
    font-size: 11px;
    padding: 2px 8px;
    border-radius: 12px;
    background: rgba(88, 166, 255, 0.15);
    color: var(--blue);
    font-weight: 500;
}

.badge-gold {
    background: rgba(212, 166, 71, 0.15);
    color: var(--gold);
}

/* Table */
.table-wrapper { overflow-x: auto; }

.rate-table, .history-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}

.rate-table th, .rate-table td,
.history-table th, .history-table td {
    padding: 8px 12px;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
    white-space: nowrap;
}

.rate-table th, .history-table th {
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-weight: 600;
    font-size: 12px;
    position: sticky;
    top: 0;
}

/* Exchange header with logo */
.ex-header {
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.ex-icon {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    object-fit: cover;
    vertical-align: middle;
}

.col-time {
    text-align: left !important;
    min-width: 140px;
    font-weight: 500;
}

.col-exchange { min-width: 90px; }

.current-row {
    background: var(--current-row-bg);
}

.current-row td { border-bottom: 2px solid var(--accent); }

.label-current {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    padding: 1px 10px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
}

/* Rate values - clean numeric font */
.rate {
    font-weight: 600;
    font-variant-numeric: tabular-nums lining-nums;
    color: var(--text-primary);
}

.rate.negative { color: var(--green); }
.rate.rate-max { color: var(--red) !important; }

.fee {
    display: block;
    font-size: 11px;
    color: var(--text-secondary);
    font-variant-numeric: tabular-nums lining-nums;
}

.fee-cell {
    font-weight: 600;
    font-variant-numeric: tabular-nums lining-nums;
}
.fee-cell.positive { color: var(--green); }
.fee-cell.negative { color: var(--red); }

.symbol-cell { font-weight: 600; color: var(--blue); }

.no-data { color: var(--text-secondary); }

.no-data-msg {
    padding: 40px;
    text-align: center;
    color: var(--text-secondary);
}

/* History table specific */
.history-table td { text-align: center; }
.history-table td:first-child { text-align: left; font-weight: 500; }

/* 按天汇总：星期六、星期日仅日期列加粗红色（两种主题均使用主题红） */
.history-period-weekend {
    color: var(--red);
    font-weight: 700;
}

.rate-table tbody tr:hover,
.history-table tbody tr:hover {
    background: var(--hover-bg);
}

/* Filters */
.filters {
    margin-bottom: 24px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 16px;
}

.filter-form {
    display: flex;
    align-items: flex-end;
    gap: 16px;
    flex-wrap: wrap;
}

.filter-group { display: flex; flex-direction: column; gap: 4px; }

.filter-group label {
    font-size: 12px;
    color: var(--text-secondary);
    font-weight: 500;
}

.filter-group select {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 13px;
    min-width: 120px;
}

/* Settings */
.settings-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 24px;
    max-width: 600px;
    margin-bottom: 24px;
}

.form-group { margin-bottom: 20px; }

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 6px;
}

.form-group input[type="text"] {
    width: 100%;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 14px;
}

.form-group input[type="text"]:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(31, 111, 235, 0.15);
}

.help-text {
    font-size: 12px;
    color: var(--text-secondary);
    margin-top: 4px;
}

.toggle-group {
    display: flex;
    gap: 16px;
}

.radio-label {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    cursor: pointer;
}

.settings-info {
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 24px;
    max-width: 600px;
}

.settings-info h3 {
    font-size: 16px;
    margin-bottom: 12px;
}

.settings-info ul {
    list-style: none;
    padding: 0;
}

.settings-info li {
    padding: 4px 0;
    font-size: 13px;
    color: var(--text-secondary);
}

.settings-info li::before {
    content: "•";
    color: var(--accent);
    margin-right: 8px;
}

/* Tabs */
.tab-nav {
    display: flex;
    gap: 2px;
    margin-bottom: 0;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-bottom: none;
    border-radius: 8px 8px 0 0;
    padding: 4px 4px 0;
    overflow: hidden;
}

.tab-btn {
    padding: 10px 24px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    border-radius: 6px 6px 0 0;
    transition: all 0.15s;
    position: relative;
}

.tab-btn:hover { color: var(--text-primary); background: var(--bg-tertiary); }

.tab-btn.active {
    color: var(--text-primary);
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-bottom-color: var(--bg-primary);
    margin-bottom: -1px;
    z-index: 1;
}

.tab-panel {
    display: none;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: 0 0 8px 8px;
    padding: 0;
    overflow: hidden;
}

.tab-panel.active { display: block; }

/* Chart */
.chart-section {
    margin: 20px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    overflow: hidden;
}

.chart-container {
    padding: 16px 20px 20px;
    height: 420px;
    position: relative;
}

/* Chart HTML legend (fixed, doesn't scroll) */
.chart-legend {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: 6px 16px;
    padding: 14px 20px 6px;
}

.chart-legend-item {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 12px;
    color: var(--text-primary);
    white-space: nowrap;
}

.chart-legend-dot {
    display: inline-block;
    width: 14px;
    height: 10px;
    border-radius: 3px;
    flex-shrink: 0;
}

/* Scrollable chart */
.chart-scroll-wrap {
    overflow-x: auto;
    overflow-y: hidden;
    padding: 0 0 12px;
}

.chart-scroll-wrap::-webkit-scrollbar { height: 8px; }
.chart-scroll-wrap::-webkit-scrollbar-track { background: var(--bg-tertiary); border-radius: 4px; }
.chart-scroll-wrap::-webkit-scrollbar-thumb { background: var(--text-secondary); border-radius: 4px; min-width: 40px; }
.chart-scroll-wrap::-webkit-scrollbar-thumb:hover { background: var(--text-primary); }

.chart-scroll-inner {
    height: 400px;
    position: relative;
}

/* Footer */
footer {
    text-align: center;
    padding: 24px;
    color: var(--text-secondary);
    font-size: 12px;
    border-top: 1px solid var(--border-color);
    margin-top: 40px;
}

/* Responsive */
@media (max-width: 768px) {
    .navbar { padding: 0 12px; flex-wrap: wrap; height: auto; padding: 8px 12px; }
    .nav-brand { font-size: 15px; }
    .container { padding: 12px; }
    .page-header { flex-direction: column; align-items: flex-start; }
    .header-actions { width: 100%; }
    .filter-form { flex-direction: column; }
    .filter-group { width: 100%; }
    .filter-group select { width: 100%; }
}