:root {
    --primary: #5b4dd4;
    --primary-light: #efedfd;
    --text-main: #1f2937;
    --text-sub: #6b7280;
    --bg-page: #f9fafb;
    --bg-card: #ffffff;
    --border: #e5e7eb;
    --dark-card-bg: #111827; 
    --success: #10b981; 
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--bg-page);
    color: var(--text-main);
    margin: 0;
    padding: 0;
}

/* --- Shared Components --- */
.mode-toggle-container { display: flex; align-items: center; justify-content: flex-end; gap: 10px; }
.mode-label { font-weight: 600; font-size: 0.85rem; color: var(--text-main); }
.switch { position: relative; display: inline-block; width: 40px; height: 22px; }
.switch input { opacity: 0; width: 0; height: 0; }
.slider { position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0; background-color: #e5e7eb; transition: .4s; border-radius: 34px; }
.slider:before { position: absolute; content: ""; height: 16px; width: 16px; left: 3px; bottom: 3px; background-color: white; transition: .4s; border-radius: 50%; box-shadow: 0 1px 2px rgba(0,0,0,0.1); }
input:checked + .slider { background-color: var(--primary); }
input:checked + .slider:before { transform: translateX(18px); }

/* --- Navigation --- */
header {
    padding: 20px 0;
    border-bottom: 1px solid var(--border);
    background: rgba(255,255,255,0.7);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 100; /* High Z-index so it sits above scrolling content */
    margin-bottom: 20px;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 0 auto;
    padding: 0 20px; /* Ensure padding on small screens */
}

.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-main);
}

.brand-icon {
    width: 36px;
    height: 36px;
    background: var(--text-main);
    color: white;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.brand-text {
    font-weight: 700;
    font-size: 1.2rem;
    letter-spacing: -0.5px;
}

.brand-text span {
    opacity: 0.5;
    font-weight: 400;
}

.nav-link {
    text-decoration: none;
    color: var(--text-sub);
    font-size: 0.9rem;
    font-weight: 500;
    margin-left: 20px;
    transition: color 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.nav-link:hover {
    color: var(--text-main);
}

/* --- Selection Grid --- */
#selectionView { padding: 40px 20px; }
.hero { text-align: center; margin-bottom: 40px; }
.search-container { position: relative; max-width: 600px; margin: 20px auto 0; }
.search-input { width: 100%; padding: 18px 24px 18px 50px; border-radius: 12px; border: 1px solid var(--border); font-size: 1rem; outline: none; box-shadow: 0 4px 20px rgba(91, 77, 212, 0.1); box-sizing: border-box; }
.search-icon { position: absolute; left: 20px; top: 50%; transform: translateY(-50%); color: #9ca3af; }

.grid-container { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 24px; max-width: 1200px; margin: 0 auto; }
.card { background: var(--bg-card); border: 1px solid var(--border); border-radius: 16px; padding: 24px; cursor: pointer; transition: transform 0.2s, box-shadow 0.2s; }
.card:hover { transform: translateY(-4px); box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05); border-color: #dbeafe; }
.tags { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 15px; }
.tag { background: #f3f4f6; color: #4b5563; padding: 4px 10px; border-radius: 6px; font-size: 0.75rem; font-weight: 500; }

/* --- Calculator Layout --- */
#calculatorView { display: none; max-width: 1200px; margin: 0 auto; padding: 40px 20px; }
.back-link { cursor: pointer; color: var(--text-sub); display: flex; align-items: center; gap: 5px; margin-bottom: 20px; font-weight: 500; transition: color 0.2s; }
.back-link:hover { color: var(--primary); }

.calc-layout { display: grid; grid-template-columns: 1.5fr 1fr; gap: 40px; align-items: start; }
.section-card { background: white; border: 1px solid var(--border); border-radius: 12px; padding: 25px; margin-bottom: 25px; }
.section-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.header-title { display: flex; align-items: center; gap: 10px; font-size: 1.1rem; font-weight: 700; }
.step-num { 
    background: var(--primary-light); 
    color: var(--primary); 
    width: 28px; 
    height: 28px; 
    border-radius: 6px; 
    display: flex; 
    align-items: center; 
    justify-content: center; 
    font-size: 0.9rem; 
    font-weight: 700; 
}

.background-grid {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1; /* Puts it behind everything else */
    
    /* The "Dots" Pattern */
    background-image: radial-gradient(#CBD5E1 1px, transparent 1px);
    background-size: 24px 24px; 
    
    /* Fades out at the bottom */
    opacity: 0.6;
    mask-image: linear-gradient(to bottom, black 40%, transparent 100%);
    -webkit-mask-image: linear-gradient(to bottom, black 40%, transparent 100%);
    pointer-events: none; /* Ensures you can click through it */
}
/* --- THE "TOWER" INPUT ROW STYLES --- */
.input-row {
    display: grid;
    /* Grid: Label (Fill Space) | Cost (120px) | Qty (110px) | Total (80px) */
    grid-template-columns: 1fr 130px 120px 90px;
    gap: 15px;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid #f3f4f6;
}
.input-row:last-child { border-bottom: none; }

.row-label { font-size: 0.9rem; font-weight: 500; color: var(--text-main); display: flex; align-items: center; gap: 8px; }
.adv-badge { font-size: 0.65rem; color: var(--primary); background: var(--primary-light); padding: 2px 6px; border-radius: 4px; font-weight: 700; white-space: nowrap; }

/* Input Wrappers */
.input-wrapper {
    display: flex;
    align-items: center;
    background: #f9fafb; /* CHANGE: Light gray background instead of white */
    border: 1px solid #e5e7eb; 
    border-radius: 8px; /* Slightly rounder */
    padding: 0 12px; /* More breathing room */
    height: 42px; /* Slightly taller for modern feel */
    transition: all 0.2s ease;
}
.input-wrapper:focus-within {
    background: #ffffff;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(91, 77, 212, 0.1); /* Soft purple halo */
}
.input-wrapper input { width: 100%; border: none; outline: none; font-size: 0.9rem; font-weight: 500; background: transparent; text-align: center; }
/* Chrome, Safari, Edge, Opera - Hide arrows */
.input-wrapper input::-webkit-outer-spin-button, .input-wrapper input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.input-wrapper span { font-size: 0.75rem; color: #9ca3af; user-select: none; white-space: nowrap; }
.row-total { text-align: right; font-weight: 700; color: var(--text-main); font-size: 0.95rem; }

/* Sub-headers for the grid columns */
.tower-header { display: grid; grid-template-columns: 1fr 130px 120px 90px; gap: 15px; margin-bottom: 10px; padding-bottom: 5px; border-bottom: 2px solid #f3f4f6; }
.col-header { font-size: 0.7rem; font-weight: 700; color: var(--text-sub); text-transform: uppercase; letter-spacing: 0.05em; }

/* --- Summary Card --- */
.summary-card { background: var(--dark-card-bg); color: white; border-radius: 16px; padding: 30px; position: sticky; top: 20px; box-shadow: 0 20px 25px -5px rgba(0,0,0,0.1); }
.big-price { font-size: 3rem; font-weight: 800; line-height: 1; margin-top: 5px; }
.summary-row { display: flex; justify-content: space-between; padding: 12px 0; border-bottom: 1px solid rgba(255,255,255,0.1); font-size: 0.9rem; }
.summary-row.profit {
    color: #10b981; /* Keep the green text */
    background: rgba(16, 185, 129, 0.1); /* Very faint green background */
    padding: 12px 15px; /* Add padding inside the highlight */
    margin: 10px -15px; /* Negative margin to pull it to the edges of the card */
    border-radius: 8px;
    border-bottom: none;
    align-items: center; /* Vertically center */
}

.summary-row.profit span:last-child {
    font-size: 1.2rem; /* Make the $ amount bigger */
    font-weight: 800;
}

/* Chart */
.chart-container { display: flex; justify-content: center; margin: 30px 0; }
.doughnut { width: 140px; height: 140px; border-radius: 50%; background: conic-gradient(var(--primary) 0% 30%, var(--text-sub) 30% 40%, var(--success) 40% 100%); position: relative; }
.doughnut::after { content: ""; position: absolute; width: 100px; height: 100px; background: var(--dark-card-bg); border-radius: 50%; top: 50%; left: 50%; transform: translate(-50%, -50%); }

/* Slider & Mobile */
input[type=range] { width: 100%; cursor: pointer; accent-color: var(--success); margin-top: 10px; }
@media (max-width: 900px) {
    .calc-layout { grid-template-columns: 1fr; }
    .summary-card { position: static; order: 1; margin-bottom: 30px; }
    /* Collapse grid on mobile */
    .tower-header { display: none; }
    .input-row { grid-template-columns: 1fr 1fr; grid-template-rows: auto auto; gap: 10px; }
    .row-label { grid-column: 1 / -1; margin-bottom: 5px; }
    .row-total { grid-column: 1 / -1; text-align: left; background: #f9fafb; padding: 8px; border-radius: 6px; margin-top: 5px; display:flex; justify-content:space-between; }
    .row-total::before { content: "Total:"; font-weight: 400; color: #6b7280; }
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    background: linear-gradient(135deg, var(--text-main) 0%, #4b5563 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    color: var(--text-sub);
    font-size: 1.1rem;
    margin-bottom: 30px;
}

/* --- COMING SOON CARDS --- */
.card.coming-soon {
    opacity: 0.7;
    background: #f3f4f6;
    border-style: dashed;
    cursor: default;
    position: relative;
    overflow: hidden;
}

.card.coming-soon:hover {
    transform: none;
    box-shadow: none;
    border-color: var(--border);
}

.badge-soon {
    display: inline-block;
    background: #e5e7eb;
    color: #6b7280;
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    padding: 4px 8px;
    border-radius: 4px;
    margin-bottom: 10px;
}

/* Empty State (Hidden by default) */
#noResults {
    display: none;
    text-align: center;
    color: var(--text-sub);
    margin-top: 40px;
    grid-column: 1 / -1; /* Spans full width of grid */
}

.category-header {
    /* TYPOGRAPHY */
    font-size: 0.85rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--primary); /* Purple text to match brand */

    /* BOX MODEL */
    background-color: var(--primary-light); /* Light purple background */
    padding: 10px 15px;
    border-radius: 8px; /* Smooth corners */
    
    /* SPACING */
    margin-top: 30px; /* Push it away from the previous section */
    margin-bottom: 15px; /* Space between header and first item */
    
    /* VISUAL ACCENT */
    border-left: 5px solid var(--primary); /* A solid left bar to anchor the eye */
    display: flex;
    align-items: center;
}

/* Ensure the first category header doesn't have extra top margin */
.category-header:first-of-type {
    margin-top: 10px;
}

.row-hidden {
    display: none !important;
}


/* 1. The Track: Thin and Neutral */
#profitMargin {
    -webkit-appearance: none;
    width: 100%;
    height: 6px; /* Much thinner (was 12px) */
    border-radius: 3px;
    background: #e5e7eb; /* Solid light gray */
    outline: none;
    margin: 25px 0 15px 0; /* Good spacing */
    cursor: pointer;
}

/* 2. The Handle: Clean, White, with Green Accent */
#profitMargin::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%; 
    background: #ffffff; /* White center */
    border: 2px solid var(--success); /* Green ring matches your "Profit" theme */
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1); /* Soft shadow for depth */
    transition: transform 0.2s, box-shadow 0.2s;
    
    /* Center the handle vertically on the thin track */
    /* (Thumb Height 24px - Track Height 6px) / 2 = 9px offset */
    margin-top: 0px; 
}

/* 3. Interaction: Hover Effect */
#profitMargin:hover::-webkit-slider-thumb {
    transform: scale(1.1);
    box-shadow: 0 6px 10px -2px rgba(16, 185, 129, 0.3); /* Green glow on hover */
}