@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

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

:root{
  --primary:#2D3436;--secondary:#636E72;--accent:#6C5CE7;
  --bg-light:#FAFAFA;--bg-dark:#1A1A2E;
  --surface-light:#FFFFFF;--surface-dark:#16213E;
  --text-light:#2D3436;--text-dark:#DFE6E9;
  --border-light:#DFE6E9;--border-dark:#2C3E50;
  --radius:12px;--font:'Inter',system-ui,sans-serif;
  /* Active theme */
  --bg:var(--bg-dark);--surface:var(--surface-dark);
  --text:var(--text-dark);--border:var(--border-dark);
}
.light-theme{
  --bg:var(--bg-light);--surface:var(--surface-light);
  --text:var(--text-light);--border:var(--border-light);
}

html{font-family:var(--font);background:var(--bg);color:var(--text);line-height:1.6;transition:background .3s,color .3s}
body{min-height:100vh;display:flex;flex-direction:column}

.header{padding:1.25rem 2rem;display:flex;align-items:center;justify-content:space-between;gap:1rem;border-bottom:1px solid var(--border);flex-wrap:wrap}
.header-left{display:flex;align-items:center;gap:.75rem}
.header h1{font-size:1.15rem;font-weight:800}
.header p{font-size:.8rem;color:var(--secondary)}
.header-actions{display:flex;gap:.5rem;flex-wrap:wrap}

.btn{padding:.5rem 1rem;border-radius:var(--radius);font-size:.82rem;font-weight:600;cursor:pointer;border:none;transition:all .2s;display:inline-flex;align-items:center;gap:.4rem;font-family:var(--font)}
.btn-primary{background:var(--accent);color:#fff}
.btn-primary:hover{transform:translateY(-1px);box-shadow:0 4px 12px rgba(108,92,231,.3)}
.btn-ghost{background:transparent;color:var(--secondary);border:1px solid var(--border)}
.btn-ghost:hover{background:var(--surface);color:var(--text)}
.btn-sm{padding:.35rem .7rem;font-size:.75rem}
.theme-btn{width:36px;height:36px;border-radius:10px;border:1px solid var(--border);background:var(--surface);cursor:pointer;font-size:1rem;display:flex;align-items:center;justify-content:center;transition:all .2s}

.layout{display:grid;grid-template-columns:320px 1fr;gap:1.5rem;max-width:1200px;width:100%;margin:0 auto;padding:1.5rem}

/* Sidebar */
.sidebar{display:flex;flex-direction:column;gap:1rem}
.search-input{width:100%;padding:.6rem .75rem;border-radius:var(--radius);border:1px solid var(--border);background:var(--surface);color:var(--text);font-size:.85rem;outline:none;transition:border-color .2s;font-family:var(--font)}
.search-input:focus{border-color:var(--accent)}
.category-filters{display:flex;gap:.3rem;flex-wrap:wrap}
.cat-btn{padding:.3rem .6rem;border-radius:8px;font-size:.72rem;font-weight:600;cursor:pointer;border:1px solid var(--border);background:transparent;color:var(--secondary);transition:all .15s;font-family:var(--font)}
.cat-btn:hover{background:var(--surface);color:var(--text)}
.cat-btn.active{background:var(--accent);color:#fff;border-color:transparent}
.pair-list{display:flex;flex-direction:column;gap:.5rem;overflow-y:auto;max-height:calc(100vh - 280px)}
.pair-card{padding:.75rem;border-radius:var(--radius);border:1px solid var(--border);background:var(--surface);cursor:pointer;transition:all .2s}
.pair-card:hover{border-color:var(--accent);transform:translateX(2px)}
.pair-card.active{border-color:var(--accent);background:rgba(108,92,231,.08)}
.pair-heading{font-size:.88rem;font-weight:700}
.pair-body{font-size:.78rem;color:var(--secondary);margin-top:.1rem}
.pair-cat{font-size:.65rem;font-weight:600;color:var(--accent);text-transform:uppercase;letter-spacing:.04em;margin-top:.25rem}

/* Preview */
.preview-panel{display:flex;flex-direction:column;gap:1rem}
.preview-area{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:2rem;min-height:300px;transition:all .3s}
.preview-heading{font-size:2.5rem;font-weight:700;margin-bottom:.5rem;line-height:1.2}
.preview-body{font-size:1rem;line-height:1.8;color:var(--secondary)}

/* Controls */
.controls{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:.75rem;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);padding:1rem}
.control{display:flex;flex-direction:column;gap:.25rem}
.control label{font-size:.72rem;font-weight:600;color:var(--secondary);text-transform:uppercase;letter-spacing:.04em}
.control input[type=range]{width:100%;accent-color:var(--accent)}
.control-value{font-size:.72rem;color:var(--accent);font-weight:600}

/* Code output */
.code-output{background:rgba(0,0,0,.3);border:1px solid var(--border);border-radius:var(--radius);padding:1rem;font-family:'Courier New',monospace;font-size:.78rem;color:var(--accent);position:relative;overflow-x:auto;white-space:pre}
.code-output .copy-btn{position:absolute;top:.5rem;right:.5rem;padding:.25rem .5rem;border-radius:6px;border:1px solid var(--border);background:var(--surface);cursor:pointer;font-size:.72rem;color:var(--secondary);font-family:var(--font)}
.code-output .copy-btn:hover{border-color:var(--accent);color:var(--accent)}

/* Favorites */
.fav-btn{width:28px;height:28px;border-radius:50%;border:none;background:transparent;cursor:pointer;font-size:1rem;display:flex;align-items:center;justify-content:center;transition:transform .15s}
.fav-btn:hover{transform:scale(1.2)}

.toast{position:fixed;bottom:2rem;right:2rem;background:var(--surface);border:1px solid var(--accent);color:var(--accent);padding:.65rem 1.1rem;border-radius:var(--radius);font-size:.82rem;font-weight:500;z-index:200;transform:translateY(100px);opacity:0;transition:all .3s}
.toast.show{transform:translateY(0);opacity:1}

@keyframes fadeIn{from{opacity:0;transform:translateY(6px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:768px){.layout{grid-template-columns:1fr;padding:1rem}.header{padding:1rem;flex-wrap:wrap}.pair-list{max-height:200px}.preview-heading{font-size:1.8rem}}