/* ══════════════════════════════════════
   Forecast Engine — Dark Theme
   ══════════════════════════════════════ */
:root {
    --bg: #0b1120;
    --surface: #111827;
    --card: rgba(17, 24, 39, .9);
    --border: rgba(255, 255, 255, .08);
    --text: #e2e8f0;
    --muted: #94a3b8;
    --accent: #3b82f6;
    --green: #22c55e;
    --red: #ef4444;
    --yellow: #f59e0b;
    --orange: #f97316;
    --purple: #a78bfa;
    --radius: 14px
}

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

body {
    font-family: 'Inter', system-ui, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.5;
    min-height: 100vh
}

.topbar {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 16px 30px;
    position: sticky;
    top: 0;
    z-index: 100
}

.topbar__inner {
    display: flex;
    align-items: center;
    justify-content: space-between
}

.brand h1 {
    font-size: 1.4rem;
    font-weight: 800;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent
}

.api-status {
    font-size: .82rem;
    padding: 4px 12px;
    border-radius: 20px;
    background: rgba(255, 255, 255, .04);
    border: 1px solid var(--border)
}

.wrap {
    padding: 24px;
    max-width: 1200px;
    margin: 0 auto
}

/* Cards */
.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    backdrop-filter: blur(10px)
}

.step-card {
    position: relative;
    overflow: visible;
    margin-bottom: 20px
}

.step-num {
    position: absolute;
    top: -12px;
    left: 20px;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 800;
    font-size: .9rem
}

.card h2 {
    font-size: 1.15rem;
    font-weight: 800;
    margin-bottom: 4px
}

.card h3 {
    font-size: 1rem;
    font-weight: 700;
    margin-bottom: 12px
}

.muted {
    color: var(--muted)
}

.small {
    font-size: .8rem
}

/* Drop zone */
.drop-zone {
    border: 2px dashed var(--border);
    border-radius: 12px;
    padding: 40px 20px;
    text-align: center;
    cursor: pointer;
    transition: .2s;
    margin-top: 16px
}

.drop-zone:hover {
    border-color: var(--accent);
    background: rgba(59, 130, 246, .04)
}

.drop-zone.dragover {
    border-color: var(--accent);
    background: rgba(59, 130, 246, .08)
}

.drop-icon {
    font-size: 2rem;
    margin-bottom: 8px
}

.upload-info {
    margin-top: 12px;
    padding: 10px;
    border-radius: 8px;
    font-size: .88rem;
    display: none
}

.upload-info.ok {
    display: block;
    background: rgba(34, 197, 94, .1);
    border: 1px solid rgba(34, 197, 94, .2);
    color: var(--green)
}

.upload-info.err {
    display: block;
    background: rgba(239, 68, 68, .1);
    border: 1px solid rgba(239, 68, 68, .2);
    color: var(--red)
}

/* Config */
.config-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 12px;
    margin: 16px 0
}

.config-block label {
    display: block;
    font-size: .78rem;
    font-weight: 700;
    color: var(--muted);
    margin-bottom: 4px;
    text-transform: uppercase;
    letter-spacing: .3px
}

.config-block input,
.config-block select {
    width: 100%;
    padding: 8px 10px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, .04);
    color: var(--text);
    font-size: .88rem;
    outline: none
}

.config-block input:focus,
.config-block select:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, .15)
}

.horizon-tabs {
    display: flex;
    gap: 4px
}

.h-tab {
    flex: 1;
    padding: 7px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--muted);
    border-radius: 8px;
    cursor: pointer;
    font-weight: 700;
    font-size: .82rem;
    transition: .15s
}

.h-tab:hover {
    border-color: var(--accent);
    color: var(--text)
}

.h-tab.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff
}

.btn-run {
    width: 100%;
    padding: 14px;
    border: none;
    border-radius: 12px;
    background: linear-gradient(135deg, #3b82f6, #8b5cf6);
    color: #fff;
    font-weight: 800;
    font-size: 1rem;
    cursor: pointer;
    margin-top: 16px;
    transition: .2s
}

.btn-run:hover {
    filter: brightness(1.1);
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, .3)
}

.btn-run:disabled {
    opacity: .5;
    cursor: wait
}

.loader {
    display: none;
    text-align: center;
    padding: 30px;
    color: var(--muted)
}

.loader.active {
    display: block
}

.spinner {
    width: 32px;
    height: 32px;
    border: 3px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin .8s linear infinite;
    margin: 0 auto 12px
}

@keyframes spin {
    to {
        transform: rotate(360deg)
    }
}

/* KPIs */
.kpi-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
    gap: 12px
}

.kpi {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px;
    position: relative;
    overflow: hidden
}

.kpi::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px
}

.kpi.orange::before {
    background: linear-gradient(90deg, #f97316, #f59e0b)
}

.kpi.blue::before {
    background: linear-gradient(90deg, #3b82f6, #6366f1)
}

.kpi.purple::before {
    background: linear-gradient(90deg, #a78bfa, #8b5cf6)
}

.kpi.green::before {
    background: linear-gradient(90deg, #22c55e, #10b981)
}

.kpi.yellow::before {
    background: linear-gradient(90deg, #f59e0b, #eab308)
}

.kpi-label {
    font-size: .75rem;
    color: var(--muted);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: .3px
}

.kpi-val {
    display: block;
    font-size: 1.5rem;
    font-weight: 800;
    color: #fff;
    margin-top: 4px
}

/* Backtest */
.bt-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 10px
}

.bt-card {
    padding: 12px;
    border-radius: 10px;
    border: 1px solid var(--border);
    background: rgba(255, 255, 255, .02)
}

.bt-name {
    font-weight: 700;
    font-size: .88rem;
    margin-bottom: 6px
}

.bt-metric {
    font-size: .78rem;
    color: var(--muted)
}

.bt-metric span {
    color: var(--text);
    font-weight: 600
}

.bt-badge {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 12px;
    font-size: .7rem;
    font-weight: 700;
    margin-left: 6px
}

.bt-badge.best {
    background: rgba(34, 197, 94, .15);
    color: var(--green)
}

.bt-badge.weight {
    background: rgba(59, 130, 246, .12);
    color: var(--accent)
}

/* Chart */
.chart-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 12px;
    flex-wrap: wrap;
    gap: 10px
}

.chart-tabs {
    display: flex;
    gap: 3px
}

.ct {
    padding: 5px 12px;
    border: 1px solid var(--border);
    background: transparent;
    color: var(--muted);
    border-radius: 6px;
    cursor: pointer;
    font-size: .78rem;
    font-weight: 700;
    transition: .15s
}

.ct:hover {
    color: var(--text);
    border-color: var(--accent)
}

.ct.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff
}

.chart-wrap {
    position: relative;
    height: 360px
}

/* Table */
.table-scroll {
    overflow-x: auto;
    max-height: 450px;
    overflow-y: auto
}

.fc-table {
    width: 100%;
    border-collapse: collapse;
    font-size: .8rem;
    white-space: nowrap
}

.fc-table thead {
    position: sticky;
    top: 0;
    z-index: 3
}

.fc-table th {
    padding: 10px 12px;
    background: var(--surface);
    color: var(--muted);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .3px;
    font-size: .7rem;
    border-bottom: 2px solid var(--border);
    text-align: right
}

.fc-table th:first-child {
    text-align: left
}

.fc-table td {
    padding: 8px 12px;
    border-bottom: 1px solid rgba(255, 255, 255, .03);
    text-align: right
}

.fc-table td:first-child {
    text-align: left;
    font-weight: 700
}

.fc-table tbody tr:hover {
    background: rgba(59, 130, 246, .04)
}

.band {
    display: inline-block;
    padding: 1px 6px;
    border-radius: 4px;
    font-size: .72rem;
    background: rgba(139, 92, 246, .1);
    color: var(--purple)
}

.btn-export {
    padding: 6px 14px;
    border: 1px solid var(--border);
    background: rgba(34, 197, 94, .08);
    color: var(--green);
    border-radius: 8px;
    cursor: pointer;
    font-weight: 700;
    font-size: .82rem;
    transition: .15s
}

.btn-export:hover {
    background: rgba(34, 197, 94, .18)
}