/* =============================================
   Pixel Density Calculator — Styles
   ============================================= */

:root {
    --bg: #0c0a1a;
    --bg-card: #13111f;
    --bg-elevated: #1a1730;
    --border: #24203d;
    --border-light: #342f58;
    --text: #e0dff0;
    --text-secondary: #9b97b8;
    --text-muted: #6b6690;
    --purple-400: #a78bfa;
    --purple-500: #8b5cf6;
    --purple-600: #7c3aed;
    --green-400: #4ade80;
    --orange-400: #fb923c;
    --blue-400: #60a5fa;

    --font-sans: 'Inter', -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --transition: 0.2s ease;
}

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

html {
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
}

.app-header {
    background: var(--bg-card);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 50;
}

.header-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0.75rem 1.25rem;
    display: flex;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo h1 {
    font-size: 1rem;
    font-weight: 700;
}

.app-main {
    max-width: 1100px;
    margin: 0 auto;
    padding: 1.5rem 1.25rem;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.25rem;
    align-items: start;
}

.panel {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
}

.panel-title {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 0.75rem;
}

.form-group {
    margin-bottom: 0.75rem;
}

.form-group label {
    display: block;
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
}

.input {
    width: 100%;
    background: var(--bg-elevated);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 0.45rem 0.625rem;
    font-size: 0.875rem;
    font-family: var(--font-sans);
    transition: var(--transition);
}

.input:focus {
    outline: none;
    border-color: var(--purple-500);
    box-shadow: 0 0 0 2px rgba(139, 92, 246, 0.15);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

.divider {
    height: 1px;
    background: var(--border);
    margin: 1rem 0;
}

/* Results */
.results-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.5rem;
    margin-top: 1rem;
}

.result-card {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 0.75rem;
    text-align: center;
}

.result-label {
    display: block;
    font-size: 0.625rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.25rem;
}

.result-value {
    font-size: 1.125rem;
    font-weight: 700;
    font-family: var(--font-mono);
    color: var(--purple-400);
}

.result-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-family: var(--font-mono);
}

/* Recs Grid */
.recs-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.5rem;
}

.rec-card {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 0.625rem;
}

.rec-card .rec-purpose {
    font-size: 0.6875rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 0.25rem;
}

.rec-card .rec-size {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--text);
    font-family: var(--font-mono);
}

/* Devices */
.devices-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 0.75rem;
}

.devices-table-wrap {
    overflow-x: auto;
}

.devices-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8125rem;
}

.devices-table th {
    text-align: left;
    padding: 0.5rem;
    font-size: 0.6875rem;
    font-weight: 700;
    color: var(--text-muted);
    text-transform: uppercase;
    border-bottom: 1px solid var(--border);
}

.devices-table td {
    padding: 0.5rem;
    border-bottom: 1px solid var(--border);
    color: var(--text-secondary);
}

.devices-table tbody tr:hover {
    background: var(--bg-elevated);
}

.devices-table .ppi-val {
    font-family: var(--font-mono);
    font-weight: 600;
    color: var(--purple-400);
}

.devices-table .current-row {
    background: rgba(139, 92, 246, 0.08);
    border-left: 3px solid var(--purple-500);
}

.devices-table .current-row td {
    color: var(--text);
    font-weight: 600;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    padding: 0.4rem 0.75rem;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.8125rem;
    font-weight: 600;
    font-family: var(--font-sans);
    cursor: pointer;
    transition: var(--transition);
}

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

.btn-ghost:hover {
    background: var(--bg-elevated);
    color: var(--text);
}

.btn-sm {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    padding: 0.2rem 0.5rem;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
    font-family: var(--font-sans);
    cursor: pointer;
    transition: var(--transition);
}

.btn-accent {
    background: rgba(139, 92, 246, 0.15);
    color: var(--purple-400);
}

.btn-accent:hover {
    background: rgba(139, 92, 246, 0.25);
}

/* Toast */
.toast {
    position: fixed;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%) translateY(80px);
    background: var(--bg-card);
    color: var(--text);
    border: 1px solid var(--border);
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius-md);
    font-size: 0.8125rem;
    font-weight: 500;
    z-index: 300;
    opacity: 0;
    transition: all 0.3s;
    pointer-events: none;
}

.toast.visible {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

@media (max-width: 800px) {
    .app-main {
        grid-template-columns: 1fr;
    }

    .results-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .form-row {
        grid-template-columns: 1fr;
    }

    .results-grid {
        grid-template-columns: 1fr 1fr;
    }

    .recs-grid {
        grid-template-columns: 1fr;
    }
}