/* ==================== VARIABLES & RESET ==================== */
:root {
    --c-light-gray: #E0E0E0;
    --c-dark-1: #1A1A1A;
    --c-dark-2: #0D0D0D;
    --c-black: #000000;
    --c-gray: #737373;
    --c-white: #FFFFFF;
    --c-pink: #E5356A;
    --c-green: #E9FFC7;

    --bg-main: var(--c-black);
    --bg-card: var(--c-dark-2);
    --bg-input: var(--c-dark-1);
    --border-color: var(--c-dark-1);

    --text-main: var(--c-white);
    --text-muted: var(--c-gray);

    --accent-buy: var(--c-green);
    --accent-sell: var(--c-pink);

    --radius: 16px;
    --radius-lg: 16px;
}

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

/* ==================== GLOBAL STYLES ==================== */
body {
    background-color: var(--bg-main);
    color: var(--text-main);
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", Helvetica, Arial, sans-serif;
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    min-height: 100vh;
    padding: 20px;
    display: flex;
    flex-direction: column;
}

/* ==================== HEADER ==================== */
.header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border: 2px solid var(--c-light-gray);
    border-radius: var(--radius-lg);
    padding: 12px 20px;
    margin-bottom: 20px;
    background: var(--bg-card);
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 12px;
}

.custom-logo {
    height: 36px;
    width: auto;
    object-fit: contain;
    display: block;
    border: none;
    outline: none;
}

.logo-text {
    font-weight: 600;
    font-size: 15px;
    letter-spacing: -0.02em;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    font-size: 13px;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--c-light-gray);
}

.nav-links a.active-btn {
    background: var(--text-main);
    color: var(--c-black);
    padding: 6px 16px;
    border-radius: 20px;
    font-weight: 600;
}

/* ==================== LAYOUT & CHART ==================== */
.layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    flex: 1;
    align-items: start;
}

.chart-section {
    width: 100%;
    height: 100%;
    min-height: 650px;
    border: 2px solid var(--c-light-gray);
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--bg-card);
}

/* ==================== CALCULATOR UI ==================== */
.calc-section {
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 16px;
}

.card-label {
    font-size: 11px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.grid2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.grid3 {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 12px;
}

.field label {
    display: block;
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 6px;
}

input, select {
    width: 100%;
    height: 44px;
    background: var(--bg-input);
    border: 1px solid var(--c-light-gray);
    border-radius: var(--radius);
    color: var(--text-main);
    padding: 0 12px;
    font-family: inherit;
    font-size: 13px;
    outline: none;
    transition: border 0.2s;
}

input:focus, select:focus {
    border-color: var(--c-white);
}

select {
    appearance: none;
    cursor: pointer;
    background: var(--bg-input) url("data:image/svg+xml;utf8,<svg fill='%23E0E0E0' height='20' viewBox='0 0 24 24' width='20' xmlns='http://www.w3.org/2000/svg'><path d='M7 10l5 5 5-5z'/></svg>") no-repeat right 10px center;
}

input::placeholder {
    color: var(--c-gray);
}

.dir-grid {
    display: flex;
    gap: 12px;
}

.dir-btn {
    flex: 1;
    height: 44px;
    background: var(--bg-input);
    border: 1px solid var(--c-gray);
    border-radius: var(--radius);
    color: var(--text-muted);
    font-family: inherit;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.dir-btn.buy.active {
    border: 1px solid var(--accent-buy);
    color: var(--accent-buy);
    background: rgba(233, 255, 199, 0.05);
}

.dir-btn.sell.active {
    border: 1px solid var(--accent-sell);
    color: var(--accent-sell);
    background: rgba(229, 53, 106, 0.05);
}

.calc-btn {
    width: 100%;
    height: 54px;
    background: var(--c-light-gray);
    color: var(--c-black);
    font-family: inherit;
    font-size: 16px;
    font-weight: 700;
    border: 2px solid var(--c-light-gray);
    border-radius: var(--radius-lg);
    cursor: pointer;
    margin-top: 5px;
    transition: transform 0.1s, background 0.2s;
}

.calc-btn:hover {
    background: var(--c-white);
    border-color: var(--c-white);
}

.calc-btn:active {
    transform: scale(0.98);
}

/* ==================== RESULTS & ALERTS ==================== */
#results, .warn {
    display: none;
    margin-top: 10px;
}

.warn {
    background: var(--bg-input);
    border: 2px solid var(--accent-sell);
    color: var(--accent-sell);
    padding: 12px;
    border-radius: var(--radius);
    font-size: 13px;
    font-weight: 500;
}

.result-card {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 16px;
    animation: fadeIn 0.3s ease;
}

.res-row {
    display: flex;
    justify-content: space-between;
    padding: 10px 0;
    border-bottom: 2px solid var(--border-color);
    font-size: 13px;
}

.res-row:last-child {
    border-bottom: none;
    padding-bottom: 0;
}

.res-label {
    color: var(--text-muted);
}

.res-val {
    font-family: 'JetBrains Mono', ui-monospace, SFMono-Regular, monospace;
    font-weight: 500;
    color: var(--c-light-gray);
}

.res-val.hl {
    color: var(--accent-buy);
    font-size: 16px;
    font-weight: 600;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* ==================== RESPONSIVE ==================== */
@media (max-width: 900px) {
    .layout { grid-template-columns: 1fr; }
    .chart-section { min-height: 400px; }
}