:root {
    --bg: #0f172a; --card: #1e293b; --text: #f8fafc; --accent: #38bdf8; --border: #334155;
    --font: 'Inter', sans-serif;
}

[data-theme="light"] {
    --bg: #f1f5f9; --card: #ffffff; --text: #0f172a; --accent: #2563eb; --border: #e2e8f0;
}

[data-theme="synthwave"] {
    --bg: #2d0b5a; --card: #420d8d; --text: #00fff2; --accent: #ff00ff; --border: #ff00ff;
}

[data-theme="matrix"] {
    --bg: #000000; --card: #000000; --text: #00ff41; --accent: #008f11; --border: #00ff41;
    --font: 'Fira Code', monospace;
}

[data-theme="dracula"] {
    --bg: #282a36; --card: #44475a; --text: #f8f8f2; --accent: #bd93f9; --border: #6272a4;
}

* { box-sizing: border-box; margin: 0; padding: 0; -webkit-tap-highlight-color: transparent; }

body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--font);
    line-height: 1.5;
    transition: background 0.3s;
}

header {
    background: rgba(0,0,0,0.2);
    backdrop-filter: blur(10px);
    position: sticky; top: 0; z-index: 100;
    padding: 15px;
    border-bottom: 1px solid var(--border);
}

.header-main { display: flex; justify-content: space-between; align-items: center; margin-bottom: 15px; }
h1 { font-size: 1.4rem; font-weight: 800; }
h1 span { color: var(--accent); }

#theme-select {
    background: var(--card); color: var(--text); border: 1px solid var(--accent);
    padding: 5px; border-radius: 5px;
}

.search-bar input {
    width: 100%; padding: 12px; border-radius: 10px; border: 1px solid var(--border);
    background: var(--card); color: var(--text); font-size: 1rem; margin-bottom: 10px;
}

.filter-nav { display: flex; overflow-x: auto; gap: 10px; padding-bottom: 5px; }
.filter-btn {
    white-space: nowrap; background: var(--card); border: 1px solid var(--border);
    color: var(--text); padding: 6px 15px; border-radius: 20px; font-size: 0.8rem;
}
.filter-btn.active { background: var(--accent); color: #000; border-color: var(--accent); }

.substance-grid {
    display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; padding: 15px;
}

.card {
    background: var(--card); border: 1px solid var(--border);
    padding: 15px; border-radius: 15px; text-align: center;
    transition: transform 0.1s; animation: fadeIn 0.3s ease;
}
.card:active { transform: scale(0.95); }
.card h3 { font-size: 0.9rem; margin: 5px 0; }
.card .label { font-size: 0.6rem; text-transform: uppercase; opacity: 0.7; color: var(--accent); }

/* Modal */
.modal {
    display: none; position: fixed; z-index: 1001; left: 0; top: 0;
    width: 100%; height: 100%; background: rgba(0,0,0,0.9);
}
.modal-content {
    background: var(--bg); margin: 10% auto; width: 90%; max-width: 500px;
    padding: 25px; border-radius: 20px; border: 1px solid var(--accent);
    max-height: 80vh; overflow-y: auto;
}
.close-btn { float: right; font-size: 28px; cursor: pointer; color: var(--accent); }

.dose-table {
    display: flex; justify-content: space-between; margin: 20px 0; gap: 8px;
}
.dose-box {
    flex: 1; background: var(--card); padding: 10px; border-radius: 10px;
    text-align: center; border-bottom: 4px solid var(--accent);
}
.dose-box small { font-size: 0.7rem; display: block; opacity: 0.7; }

.info-section { margin-bottom: 15px; }
.info-section h4 { color: var(--accent); font-size: 0.9rem; margin-bottom: 5px; }
.info-section p { font-size: 0.85rem; opacity: 0.9; }

footer { text-align: center; padding: 20px; opacity: 0.5; font-size: 0.7rem; }

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

@media (min-width: 768px) {
    .substance-grid { grid-template-columns: repeat(4, 1fr); }
}