diff --git a/public/style.css b/public/style.css
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+/* =========================================================
+   CYBER BEATS — Koyu Neon Stüdyo Teması
+   ========================================================= */
+:root {
+  --bg: #07070f;
+  --bg2: #0d0d1a;
+  --panel: #12121f;
+  --panel2: #1a1a2c;
+  --neon-cyan: #00f0ff;
+  --neon-pink: #ff2bd6;
+  --neon-green: #39ff88;
+  --neon-yellow: #ffe14d;
+  --neon-red: #ff3d5e;
+  --neon-orange: #ffa34d;
+  --neon-purple: #b26bff;
+  --text: #e8e8f4;
+  --dim: #6a6a85;
+  --grid-line: rgba(0, 240, 255, 0.12);
+}
+
+* { margin: 0; padding: 0; box-sizing: border-box; }
+
+html, body { height: 100%; }
+
+body {
+  font-family: 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
+  background: var(--bg);
+  color: var(--text);
+  overflow: hidden;
+  background-image:
+    radial-gradient(circle at 20% 10%, rgba(0, 240, 255, 0.08), transparent 40%),
+    radial-gradient(circle at 80% 90%, rgba(255, 43, 214, 0.08), transparent 45%),
+    radial-gradient(circle at 50% 50%, rgba(57, 255, 136, 0.04), transparent 60%);
+}
+
+.stage {
+  display: flex;
+  flex-direction: column;
+  max-width: 1040px;
+  min-height: 100vh;
+  margin: 0 auto;
+  padding: 20px 30px 14px;
+  background: linear-gradient(160deg, rgba(18, 18, 31, 0.92), rgba(10, 10, 20, 0.97));
+  border-left: 1px solid var(--grid-line);
+  border-right: 1px solid var(--grid-line);
+  box-shadow:
+    0 0 40px rgba(0, 240, 255, 0.07),
+    0 0 90px rgba(255, 43, 214, 0.05);
+}
+
+/* ---- Üst bar ---- */
+.topbar {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding-bottom: 12px;
+  border-bottom: 1px solid var(--grid-line);
+}
+.brand { display: flex; align-items: center; gap: 12px; }
+.brand-icon {
+  font-size: 26px;
+  color: var(--neon-cyan);
+  text-shadow: 0 0 14px var(--neon-cyan);
+}
+.brand h1 {
+  font-size: 22px;
+  letter-spacing: 3px;
+  font-weight: 800;
+}
+.brand h1 .accent { color: var(--neon-pink); text-shadow: 0 0 12px var(--neon-pink); }
+
+.led-grid {
+  display: flex;
+  gap: 5px;
+  margin-left: 16px;
+}
+.led-grid .led {
+  width: 7px;
+  height: 7px;
+  border-radius: 50%;
+  background: rgba(120, 120, 160, 0.35);
+  transition: all 90ms ease;
+}
+.led-grid .led.on {
+  background: var(--neon-green);
+  box-shadow: 0 0 8px var(--neon-green);
+}
+
+.status { display: flex; align-items: center; gap: 8px; }
+.play-indicator {
+  font-size: 14px;
+  color: var(--dim);
+  transition: all 150ms ease;
+}
+.play-indicator.running {
+  color: var(--neon-green);
+  text-shadow: 0 0 10px var(--neon-green);
+  animation: pulse 900ms infinite alternate;
+}
+@keyframes pulse { from { opacity: 0.45; } to { opacity: 1; } }
+.status-text {
+  font-size: 12px;
+  letter-spacing: 2px;
+  color: var(--dim);
+}
+.status-text.running { color: var(--neon-green); }
+
+/* ---- Kontroller ---- */
+.controls {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 14px;
+  padding: 14px 0;
+}
+.transport { display: flex; align-items: center; gap: 10px; }
+
+.btn {
+  border: none;
+  cursor: pointer;
+  font-family: inherit;
+  font-weight: 700;
+  border-radius: 10px;
+  transition: transform 80ms ease, box-shadow 150ms ease, background 150ms ease;
+}
+.btn:active { transform: translateY(1px) scale(0.97); }
+
+.btn-play, .btn-stop {
+  width: 52px;
+  height: 48px;
+  font-size: 18px;
+  background: linear-gradient(145deg, #18d8e8, #0aa0c0);
+  color: #04222a;
+  box-shadow: 0 0 18px rgba(0, 240, 255, 0.35);
+}
+.btn-play:hover { box-shadow: 0 0 26px rgba(0, 240, 255, 0.7); }
+.btn-play.running { background: linear-gradient(145deg, #ffe14d, #ffb300); color: #332500; box-shadow: 0 0 20px rgba(255, 225, 77, 0.6); }
+.btn-stop { background: linear-gradient(145deg, #ff5166, #e02b44); color: #2b0006; box-shadow: 0 0 18px rgba(255, 61, 94, 0.4); }
+.btn-clear {
+  padding: 0 16px;
+  height: 42px;
+  font-size: 12px;
+  letter-spacing: 1px;
+  background: rgba(255, 255, 255, 0.04);
+  color: var(--dim);
+  border: 1px solid rgba(255, 255, 255, 0.1);
+}
+.btn-clear:hover { border-color: var(--neon-red); color: var(--neon-red); box-shadow: 0 0 12px rgba(255, 61, 94, 0.3); }
+
+.bpm-box {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  flex: 1;
+  justify-content: flex-end;
+}
+.bpm-label { font-size: 12px; letter-spacing: 2px; color: var(--dim); }
+input[type="range"] {
+  -webkit-appearance: none;
+  appearance: none;
+  width: 210px;
+  height: 6px;
+  border-radius: 4px;
+  background: linear-gradient(90deg, #0aa0c0, var(--neon-pink));
+  outline: none;
+  cursor: pointer;
+}
+input[type="range"]::-webkit-slider-thumb {
+  -webkit-appearance: none;
+  appearance: none;
+  width: 18px;
+  height: 18px;
+  border-radius: 50%;
+  background: var(--text);
+  border: 2px solid var(--neon-pink);
+  box-shadow: 0 0 12px var(--neon-pink);
+  cursor: pointer;
+}
+.bpm-value {
+  font-size: 30px;
+  font-weight: 800;
+  min-width: 62px;
+  text-align: right;
+  color: var(--neon-cyan);
+  text-shadow: 0 0 12px rgba(0, 240, 255, 0.5);
+  font-variant-numeric: tabular-nums;
+}
+.bpm-unit { font-size: 12px; color: var(--dim); letter-spacing: 1px; }
+
+/* ---- Adım başlıkları ---- */
+.step-labels {
+  display: grid;
+  grid-template-columns: 108px repeat(16, 1fr);
+  gap: 5px;
+  padding: 0 2px 6px 2px;
+}
+.step-labels .step-num {
+  text-align: center;
+  font-size: 12px;
+  color: var(--dim);
+  font-variant-numeric: tabular-nums;
+  font-weight: 600;
+}
+.step-labels .step-num.group { color: var(--neon-cyan); text-shadow: 0 0 6px rgba(0, 240, 255, 0.4); }
+
+/* ---- Matris sarmalayıcı ---- */
+.matrix-wrap { display: flex; gap: 10px; align-items: stretch; }
+.row-labels {
+  display: flex;
+  flex-direction: column;
+  gap: 5px;
+  width: 98px;
+  flex-shrink: 0;
+}
+.row-name {
+  height: 44px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  font-size: 13px;
+  font-weight: 800;
+  letter-spacing: 1px;
+  border-radius: 8px;
+  background: rgba(255, 255, 255, 0.03);
+  border: 1px solid rgba(255, 255, 255, 0.07);
+}
+.row-name.kick  { color: var(--neon-red);    border-color: rgba(255, 61, 94, 0.3); }
+.row-name.snare { color: var(--neon-orange); border-color: rgba(255, 163, 77, 0.3); }
+.row-name.hat   { color: var(--neon-cyan);   border-color: rgba(0, 240, 255, 0.3); }
+.row-name.synth { color: var(--neon-purple); border-color: rgba(178, 107, 255, 0.3); }
+
+/* ---- Ana matris ---- */
+.matrix {
+  display: flex;
+  flex-direction: column;
+  gap: 5px;
+  flex: 1;
+  position: relative;
+}
+
+.step-row {
+  display: grid;
+  grid-template-columns: repeat(16, 1fr);
+  gap: 5px;
+}
+
+.step-cell {
+  position: relative;
+  height: 44px;
+  border-radius: 7px;
+  background: rgba(255, 255, 255, 0.025);
+  border: 1px solid rgba(255, 255, 255, 0.06);
+  cursor: pointer;
+  transition: background 90ms ease, box-shadow 90ms ease, transform 70ms ease;
+}
+.step-cell:hover { background: rgba(255, 255, 255, 0.07); }
+.step-cell:active { transform: scale(0.94); }
+
+/* hücre içi neon ışık dolgusu */
+.step-cell .cell-glow {
+  position: absolute;
+  inset: 6px;
+  border-radius: 5px;
+  opacity: 0;
+  transition: opacity 90ms ease;
+}
+
+/* ---- aktif (ON) hücreler ---- */
+.step-row.kick-row  .step-cell.on { background: rgba(255, 61, 94, 0.14); border-color: rgba(255, 61, 94, 0.7); }
+.step-row.snare-row .step-cell.on { background: rgba(255, 163, 77, 0.14); border-color: rgba(255, 163, 77, 0.7); }
+.step-row.hat-row   .step-cell.on { background: rgba(0, 240, 255, 0.14);  border-color: rgba(0, 240, 255, 0.7); }
+.step-row.synth-row .step-cell.on { background: rgba(178, 107, 255, 0.16); border-color: rgba(178, 107, 255, 0.7); }
+
+.step-cell.on .cell-glow { opacity: 1; }
+.step-row.kick-row  .step-cell.on .cell-glow { background: radial-gradient(circle, rgba(255,61,94,0.65), transparent 70%); box-shadow: 0 0 12px rgba(255,61,94,0.9); }
+.step-row.snare-row .step-cell.on .cell-glow { background: radial-gradient(circle, rgba(255,163,77,0.6), transparent 70%); box-shadow: 0 0 12px rgba(255,163,77,0.9); }
+.step-row.hat-row   .step-cell.on .cell-glow { background: radial-gradient(circle, rgba(0,240,255,0.6), transparent 70%); box-shadow: 0 0 12px rgba(0,240,255,0.85); }
+.step-row.synth-row .step-cell.on .cell-glow { background: radial-gradient(circle, rgba(178,107,255,0.6), transparent 70%); box-shadow: 0 0 12px rgba(178,107,255,0.85); }
+
+/* ---- Playhead sütun ışığı ---- */
+.step-col-head {
+  position: absolute;
+  top: 0;
+  bottom: 0;
+  width: calc((100% - 75px) / 16);
+  pointer-events: none;
+  background: linear-gradient(180deg, rgba(255, 255, 255, 0.25), rgba(255, 255, 255, 0.02));
+  border-radius: 7px;
+  box-shadow: 0 0 22px rgba(255, 255, 255, 0.55), 0 0 8px rgba(0, 240, 255, 0.6);
+  opacity: 0;
+  transition: opacity 60ms ease, left 40ms linear;
+  z-index: 2;
+}
+.step-col-head.active { opacity: 1; }
+
+/* tıklandığında tetik parlaması */
+.step-cell.hit .cell-glow { opacity: 1; transform: scale(1.06); }
+
+/* ---- Alt bilgi ---- */
+.footbar {
+  display: flex;
+  justify-content: center;
+  gap: 22px;
+  flex-wrap: wrap;
+  padding-top: 14px;
+  margin-top: auto;
+  border-top: 1px solid rgba(255, 255, 255, 0.05);
+}
+.hint {
+  font-size: 11px;
+  color: var(--dim);
+  letter-spacing: 0.5px;
+}
+.hint:first-child::before { content: "▶ "; color: var(--neon-green); }
+.hint:last-child::before { content: "♪ "; color: var(--neon-pink); }
+
+@media (max-width: 860px) {
+  body { overflow: auto; }
+  .stage { padding: 14px; }
+  .step-cell { height: 36px; }
+  .row-name { height: 36px; font-size: 11px; }
+  .controls { flex-direction: column; align-items: stretch; }
+  .bpm-box { justify-content: center; }
+  input[type="range"] { width: 60%; }
+}