/* ══════════════════════════════════════════════════════════════════
   TraceCurrent (pcb-trace-ampacity) — Bespoke Electronics Theme
   Domain: Electronics & Electrical Engineering / PCB Design
   ══════════════════════════════════════════════════════════════════ */

:root {
    --bg-primary: #090d16;
    --bg-surface: #111827;
    --bg-card: #162032;
    --bg-hover: #1f2937;
    --text-primary: #f9fafb;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --accent: #f59e0b;           /* Copper Gold */
    --accent-glow: rgba(245, 158, 11, 0.15);
    --accent-pcb: #10b981;        /* Soldermask Green */
    --accent-cyan: #06b6d4;       /* Lab Cyan */
    --border: rgba(255, 255, 255, 0.1);
    --border-hover: rgba(245, 158, 11, 0.4);
    --success: #22c55e;
    --warning: #f59e0b;
    --error: #ef4444;

    /* Fonts */
    --font-heading: 'Outfit', system-ui, sans-serif;
    --font-body: 'Inter', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', Consolas, monospace;
}

body {
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--font-body);
    margin: 0;
    padding: 0;
    line-height: 1.6;
}

.app-header {
    text-align: center;
    padding: 2.5rem 1rem 1.5rem;
    background: linear-gradient(180deg, rgba(245, 158, 11, 0.05) 0%, transparent 100%);
    border-bottom: 1px solid var(--border);
}

.header-inner {
    max-width: 800px;
    margin: 0 auto;
}

.badge-category {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-radius: 9999px;
    background: rgba(6, 182, 212, 0.15);
    color: var(--accent-cyan);
    margin-bottom: 0.75rem;
}

.app-header h1 {
    font-family: var(--font-heading);
    font-size: clamp(2rem, 5vw, 3.25rem);
    font-weight: 800;
    margin: 0 0 0.5rem;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.app-header .subtitle {
    font-size: clamp(1rem, 2.5vw, 1.25rem);
    color: var(--text-secondary);
    margin: 0;
}

.app-main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.5rem 1rem 4rem;
}

/* Calculator Card */
.calculator-card {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: 1rem;
    overflow: hidden;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.5);
    margin-bottom: 3rem;
}

/* Mode Switcher Tabs */
.mode-tabs {
    display: flex;
    background: rgba(0, 0, 0, 0.3);
    border-bottom: 1px solid var(--border);
}

.tab-btn {
    flex: 1;
    padding: 1rem 1.25rem;
    background: transparent;
    border: none;
    border-bottom: 3px solid transparent;
    color: var(--text-secondary);
    font-family: var(--font-heading);
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.03);
}

.tab-btn.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
    background: var(--bg-surface);
}

/* Layout Grid */
.calculator-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
    padding: 2rem;
}

@media (min-width: 900px) {
    .calculator-grid {
        grid-template-columns: 460px 1fr;
    }
}

.section-title {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    margin: 0 0 1.25rem;
    color: var(--accent);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Form Controls */
.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.field-hint {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.35rem;
    line-height: 1.4;
}

.input-with-unit {
    display: flex;
    align-items: center;
    border: 1px solid var(--border);
    border-radius: 0.5rem;
    background: var(--bg-primary);
    overflow: hidden;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.input-with-unit:focus-within {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.input-with-unit input,
.input-with-unit select {
    flex: 1;
    background: transparent;
    border: none;
    padding: 0.75rem 1rem;
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 1rem;
    outline: none;
}

.input-with-unit select {
    font-family: var(--font-body);
    cursor: pointer;
}

.unit-badge {
    padding: 0.75rem 1rem;
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-secondary);
    font-family: var(--font-mono);
    font-size: 0.875rem;
    font-weight: 600;
    border-left: 1px solid var(--border);
}

.unit-select {
    border-left: 1px solid var(--border) !important;
    background: rgba(255, 255, 255, 0.05) !important;
    width: auto !important;
    flex: none !important;
}

/* Radio Segmented Switcher */
.radio-segmented {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
    background: var(--bg-primary);
    padding: 0.35rem;
    border-radius: 0.5rem;
    border: 1px solid var(--border);
}

.radio-segmented input {
    display: none;
}

.radio-segmented label {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.6rem 0.5rem;
    margin: 0;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-secondary);
    border-radius: 0.375rem;
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: center;
}

.radio-segmented input:checked + label {
    background: var(--bg-card);
    color: var(--accent);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(245, 158, 11, 0.3);
}

/* Slider Component */
.slider-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.slider-header label {
    margin: 0;
}

.slider-value-display {
    font-family: var(--font-mono);
    font-weight: 700;
    color: var(--accent);
    font-size: 0.95rem;
    background: var(--accent-glow);
    padding: 0.15rem 0.6rem;
    border-radius: 0.35rem;
    border: 1px solid rgba(245, 158, 11, 0.3);
}

.slider-container input[type="range"] {
    width: 100%;
    height: 8px;
    border-radius: 4px;
    background: var(--bg-primary);
    outline: none;
    -webkit-appearance: none;
}

.slider-container input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: var(--accent);
    cursor: pointer;
    box-shadow: 0 0 10px var(--accent);
    transition: transform 0.1s ease;
}

.slider-container input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.15);
}

/* Checkbox Card */
.checkbox-card {
    background: rgba(245, 158, 11, 0.04);
    border: 1px solid rgba(245, 158, 11, 0.2);
    border-radius: 0.5rem;
    padding: 0.85rem 1rem;
    transition: border-color 0.2s ease;
}

.checkbox-card:hover {
    border-color: var(--accent);
}

.checkbox-label {
    display: flex !important;
    align-items: flex-start;
    gap: 0.75rem;
    cursor: pointer;
    margin: 0 !important;
}

.checkbox-label input[type="checkbox"] {
    width: 1.2rem;
    height: 1.2rem;
    margin-top: 0.15rem;
    accent-color: var(--accent);
    cursor: pointer;
}

.checkbox-text {
    display: flex;
    flex-direction: column;
}

.checkbox-text strong {
    color: var(--accent);
    font-size: 0.875rem;
}

.checkbox-text span {
    font-size: 0.75rem;
    color: var(--text-secondary);
    font-weight: normal;
}

/* Results Output Styling */
.warning-banner {
    display: flex;
    align-items: flex-start;
    gap: 0.85rem;
    background: rgba(239, 68, 68, 0.12);
    border: 1px solid var(--error);
    border-radius: 0.75rem;
    padding: 1rem 1.25rem;
    margin-bottom: 1.5rem;
    animation: fadeIn 0.3s ease;
}

.warning-banner.hidden {
    display: none;
}

.warning-icon {
    font-size: 1.5rem;
    line-height: 1;
}

.warning-content strong {
    color: var(--error);
    display: block;
    margin-bottom: 0.25rem;
}

.warning-content p {
    margin: 0;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Hero Result Card */
.result-hero-card {
    background: linear-gradient(135deg, rgba(245, 158, 11, 0.12) 0%, rgba(16, 185, 129, 0.05) 100%);
    border: 1px solid rgba(245, 158, 11, 0.35);
    border-radius: 0.85rem;
    padding: 1.75rem 1.5rem;
    text-align: center;
    margin-bottom: 1.5rem;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
}

.result-hero-label {
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--accent-cyan);
    margin-bottom: 0.5rem;
}

.result-hero-primary {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 0.4rem;
    margin-bottom: 0.5rem;
}

.hero-number {
    font-family: var(--font-mono);
    font-size: clamp(2.5rem, 6vw, 3.75rem);
    font-weight: 800;
    color: var(--accent);
    line-height: 1;
}

.hero-unit {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-secondary);
}

.result-hero-secondary {
    font-family: var(--font-mono);
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.result-hero-secondary .separator {
    margin: 0 0.5rem;
    color: var(--text-muted);
}

/* Results Grid Tiles */
.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.result-tile {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 0.65rem;
    padding: 1rem;
    display: flex;
    flex-direction: column;
}

.tile-label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.03em;
    margin-bottom: 0.35rem;
}

.tile-value {
    font-family: var(--font-mono);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.2rem;
}

.tile-sub {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Canvas Diagram Card */
.diagram-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 0.85rem;
    padding: 1.25rem;
    margin-bottom: 1.5rem;
}

.diagram-card h3 {
    font-family: var(--font-heading);
    font-size: 1rem;
    font-weight: 700;
    margin: 0 0 1rem;
    color: var(--text-primary);
}

.canvas-wrapper {
    width: 100%;
    overflow-x: auto;
    border-radius: 0.5rem;
    background: #04070d;
    border: 1px solid var(--border);
}

canvas {
    display: block;
    max-width: 100%;
    height: auto;
    margin: 0 auto;
}

.diagram-caption {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin: 0.75rem 0 0;
    text-align: center;
}

/* Matrix Comparison Table */
.comparison-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 0.85rem;
    padding: 1.25rem;
}

.comparison-card h3 {
    font-family: var(--font-heading);
    font-size: 1rem;
    font-weight: 700;
    margin: 0 0 1rem;
    color: var(--text-primary);
}

.table-responsive {
    overflow-x: auto;
}

.matrix-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.85rem;
    text-align: left;
}

.matrix-table th,
.matrix-table td {
    padding: 0.75rem 0.85rem;
    border-bottom: 1px solid var(--border);
}

.matrix-table th {
    background: rgba(0, 0, 0, 0.3);
    color: var(--accent-cyan);
    font-family: var(--font-heading);
    font-weight: 700;
}

.matrix-table td {
    color: var(--text-secondary);
    font-family: var(--font-mono);
}

.matrix-table td:first-child {
    font-family: var(--font-body);
    color: var(--text-primary);
}

/* Article Styling */
.explanatory-article {
    background: var(--bg-surface);
    border: 1px solid var(--border);
    border-radius: 1rem;
    padding: 2.5rem 2rem;
    margin-top: 3rem;
}

.explanatory-article h2 {
    font-family: var(--font-heading);
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--accent);
    margin-top: 0;
    margin-bottom: 1.25rem;
}

.explanatory-article h3 {
    font-family: var(--font-heading);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-top: 2rem;
    margin-bottom: 0.75rem;
}

.explanatory-article p {
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
}

.explanatory-article ul,
.explanatory-article ol {
    color: var(--text-secondary);
    padding-left: 1.5rem;
    margin-bottom: 1.5rem;
}

.explanatory-article li {
    margin-bottom: 0.5rem;
}

.math-block {
    background: var(--bg-primary);
    border-left: 3px solid var(--accent);
    padding: 1rem 1.25rem;
    font-family: var(--font-mono);
    font-size: 1.05rem;
    color: var(--accent-cyan);
    border-radius: 0 0.5rem 0.5rem 0;
    margin: 1.25rem 0;
}

.hidden {
    display: none !important;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-6px); }
    to { opacity: 1; transform: translateY(0); }
}