diff --git a/src/styles.css b/src/styles.css
index 8a7c263..a1baaee 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -1,3 +1,560 @@
+/* Grid-based TV-Optimized Layout Framework */
+
+:root {
+  color-scheme: dark;
+  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
+  background:
+    radial-gradient(circle at top, rgba(48, 72, 104, 0.35), transparent 42%),
+    linear-gradient(180deg, #0b1220 0%, #070b13 100%);
+  color: #f4f7fb;
+  
+  /* Layout constants */
+  --bottom-bar-height: 100px;
+  --sidebar-min-width: 280px;
+  --sidebar-max-width: 380px;
+  --gap-size: 0.75rem;
+  --padding-size: 0.75rem;
+}
+
+* {
+  box-sizing: border-box;
+  margin: 0;
+  padding: 0;
+}
+
+html, body {
+  height: 100%;
+  width: 100%;
+  overflow: hidden;
+  background: transparent;
+}
+
+/* Main App Container - fills viewport accounting for browser chrome */
+#app {
+  width: 100%;
+  height: 100%;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  padding: 0.5rem;
+}
+
+#app > * {
+  width: 100%;
+  height: calc(100vh - 100px);
+  max-width: 100%;
+  max-height: calc(100vh - 100px);
+  min-width: 0;
+  min-height: 0;
+}
+
+/* Main Layout Grid */
+.layout {
+  width: 100%;
+  height: 100%;
+  display: grid;
+  grid-template-areas:
+    "main sidebar"
+    "bottom bottom";
+  grid-template-columns: 1fr minmax(var(--sidebar-min-width), var(--sidebar-max-width));
+  grid-template-rows: 1fr var(--bottom-bar-height);
+  gap: var(--gap-size);
+  padding: var(--padding-size);
+  overflow: hidden;
+}
+
+/* Game Area - Main left section */
+.game-area {
+  grid-area: main;
+  display: flex;
+  flex-direction: column;
+  min-width: 0;
+  min-height: 0;
+  overflow: hidden;
+}
+
+/* Board shell fills the game area */
+.board-shell {
+  flex: 1;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  border-radius: 1.25rem;
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  background: rgba(9, 16, 29, 0.72);
+  backdrop-filter: blur(20px);
+  padding: 0.5rem;
+  min-height: 0;
+  overflow: hidden;
+}
+
+/* Board - fits within shell */
+.board {
+  position: relative;
+  width: 100%;
+  height: 100%;
+  max-width: 100%;
+  max-height: 100%;
+  aspect-ratio: var(--board-columns) / var(--board-rows);
+  display: grid;
+  grid-template-columns: repeat(var(--board-columns), 1fr);
+  grid-template-rows: repeat(var(--board-rows), 1fr);
+  gap: clamp(2px, 0.3cqmin, 4px);
+  margin: 0 auto;
+}
+
+/* Sidebar - Right panel */
+.sidebar {
+  grid-area: sidebar;
+  display: flex;
+  flex-direction: column;
+  gap: 0.75rem;
+  min-width: 0;
+  overflow: hidden;
+}
+
+/* Bottom bar - Fixed height player scores */
+.scoreboard {
+  grid-area: bottom;
+  display: grid;
+  grid-template-columns: repeat(var(--player-count, 3), 1fr);
+  gap: 0.75rem;
+  height: 100%;
+  overflow: hidden;
+}
+
+.score-card {
+  border: 1px solid rgba(255, 255, 255, 0.1);
+  border-radius: 1rem;
+  padding: 0.75rem 1rem;
+  background: linear-gradient(180deg, rgba(255, 255, 255, 0.08), rgba(255, 255, 255, 0.02));
+  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.06);
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  min-height: 0;
+}
+
+.score-card.active {
+  border-color: color-mix(in srgb, var(--player-color) 55%, white);
+  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.08), 0 0 24px var(--player-glow);
+}
+
+/* Sidebar panels */
+.panel {
+  border-radius: 1.25rem;
+  border: 1px solid rgba(255, 255, 255, 0.08);
+  background: rgba(9, 16, 29, 0.72);
+  backdrop-filter: blur(20px);
+  padding: 0.75rem;
+  display: flex;
+  flex-direction: column;
+  min-height: 0;
+}
+
+.controls-panel {
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  gap: 0.6rem;
+  overflow: auto;
+}
+
+.log-panel {
+  max-height: 120px;
+  flex-shrink: 0;
+}
+
+/* Cell styling */
+.cell {
+  position: relative;
+  background: rgba(255, 255, 255, 0.03);
+  border-radius: clamp(4px, 15%, 0.6rem);
+  border: 1px solid rgba(255, 255, 255, 0.05);
+  overflow: hidden;
+  min-width: 0;
+  min-height: 0;
+}
+
+.cell__shade {
+  position: absolute;
+  inset: 0;
+  background: linear-gradient(180deg, rgba(255, 255, 255, 0.03), var(--column-tint));
+}
+
+.cell__root-ring {
+  position: absolute;
+  inset: 18% 18%;
+  border: 1px dashed rgba(255, 255, 255, 0.28);
+  border-radius: 999px;
+}
+
+.cell__node,
+.cell__target-label {
+  position: absolute;
+  inset: 50% auto auto 50%;
+  transform: translate(-50%, -50%);
+}
+
+.cell__node {
+  width: min(40%, 1.4rem);
+  height: min(40%, 1.4rem);
+  min-width: 8px;
+  min-height: 8px;
+  border-radius: 50%;
+  background: var(--node-color);
+  box-shadow: 0 0 0 0.15rem rgba(255, 255, 255, 0.06), 0 0 1rem var(--node-glow);
+}
+
+.cell.selected {
+  border-color: rgba(255, 255, 255, 0.55);
+  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.22);
+}
+
+.cell.pending {
+  border-color: rgba(255, 255, 255, 0.28);
+  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.12), 0 0 18px rgba(255, 255, 255, 0.08);
+}
+
+.cell.pending .cell__node {
+  box-shadow: 0 0 0 0.18rem rgba(255, 255, 255, 0.08), 0 0 1.1rem var(--node-glow), 0 0 1.5rem rgba(255, 255, 255, 0.08);
+}
+
+.cell.target {
+  border-color: rgba(255, 255, 255, 0.22);
+  background: rgba(255, 255, 255, 0.05);
+}
+
+.cell.target:hover {
+  transform: translateY(-1px);
+}
+
+.cell__target-label {
+  width: min(60%, 1.5rem);
+  height: min(60%, 1.5rem);
+  display: grid;
+  place-items: center;
+  border-radius: 999px;
+  background: rgba(255, 255, 255, 0.09);
+  border: 1px solid rgba(255, 255, 255, 0.18);
+  font-weight: 700;
+  font-size: clamp(0.6rem, 2cqmin, 0.9rem);
+}
+
+/* Board overlays */
+.board__lines {
+  position: absolute;
+  inset: 0;
+  width: 100%;
+  height: 100%;
+  pointer-events: none;
+  filter: drop-shadow(0 0 8px rgba(255, 255, 255, 0.18));
+  z-index: 1;
+}
+
+.board__fx {
+  position: absolute;
+  inset: 0;
+  width: 100%;
+  height: 100%;
+  pointer-events: none;
+  z-index: 4;
+}
+
+.board__drop-layer {
+  position: absolute;
+  inset: 0;
+  pointer-events: none;
+  overflow: hidden;
+  z-index: 5;
+}
+
+.board__energy-layer {
+  position: absolute;
+  inset: 0;
+  pointer-events: none;
+  z-index: 4;
+}
+
+.board__energy-cell {
+  position: absolute;
+  border-radius: clamp(4px, 15%, 0.6rem);
+  background:
+    radial-gradient(circle at 50% 50%, rgba(255, 255, 255, 0.95), color-mix(in srgb, var(--flash-color) 70%, #ffe08a) 34%, rgba(255, 224, 138, 0.18) 72%, transparent 100%),
+    linear-gradient(180deg, rgba(255, 255, 255, 0.18), transparent);
+  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.12), 0 0 18px color-mix(in srgb, var(--flash-color) 55%, #ffe08a);
+  opacity: 0;
+}
+
+.board__energy-cell--sunlight {
+  inset: 12%;
+  background:
+    linear-gradient(180deg, rgba(255, 244, 214, 0.05), rgba(255, 244, 214, 0.008)),
+    radial-gradient(circle at 50% 50%, rgba(255, 242, 196, 0.11), color-mix(in srgb, var(--flash-color) 10%, #ffe3a3) 42%, rgba(255, 221, 128, 0.03) 72%, transparent 100%);
+  box-shadow: inset 0 0 0 1px rgba(255, 245, 224, 0.02), 0 0 6px color-mix(in srgb, var(--flash-color) 8%, #ffe3a3);
+}
+
+.board--sunlight .board__energy-cell--sunlight,
+.board--branches .board__energy-cell,
+.board--bonus .board__energy-cell--bonus {
+  animation: energy-cell-flash 0.48s ease forwards;
+  animation-delay: var(--flash-delay, 0ms);
+}
+
+.board__energy-cell--bonus {
+  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.18), 0 0 22px rgba(255, 216, 94, 0.9);
+}
+
+.board--bonus .board__drop--bonus {
+  animation: sunlight-drop 0.85s cubic-bezier(0.2, 0.7, 0.2, 1) forwards;
+}
+
+.board__drop-core,
+.board__drop-spark {
+  position: absolute;
+  inset: 0;
+  border-radius: 999px;
+}
+
+.board__drop-core {
+  background: radial-gradient(circle at 35% 30%, rgba(255, 255, 255, 0.98), color-mix(in srgb, var(--drop-color) 72%, #ffe38a) 45%, rgba(255, 227, 138, 0.18) 100%);
+  box-shadow: 0 0 18px color-mix(in srgb, var(--drop-color) 40%, #ffe38a), 0 0 32px rgba(255, 236, 174, 0.65);
+}
+
+.board__drop-spark {
+  inset: 35%;
+  border: 1px solid rgba(255, 248, 220, 0.95);
+  opacity: 0.9;
+}
+
+.board__drop-spark--a { transform: translate(-0.8rem, -0.15rem) scale(0.55); }
+.board__drop-spark--b { transform: translate(0.75rem, -0.1rem) scale(0.45); }
+.board__drop-spark--c { transform: translate(0.1rem, -0.75rem) scale(0.35); }
+
+.board__root-burst,
+.board__disease-mark,
+.board__sunbeam-burst {
+  opacity: 0;
+}
+
+.board__root-burst circle,
+.board__sunbeam-burst {
+  fill: color-mix(in srgb, var(--burst-color, #ffd85e) 70%, white);
+  stroke: rgba(255, 255, 255, 0.65);
+  stroke-width: 0.35;
+}
+
+.board__root-burst text {
+  fill: #08111c;
+  font-size: 2.1px;
+  font-weight: 800;
+}
+
+.board__disease-mark circle {
+  fill: rgba(162, 255, 142, 0.2);
+  stroke: rgba(162, 255, 142, 0.9);
+  stroke-width: 0.35;
+}
+
+.board__disease-mark path {
+  stroke: rgba(162, 255, 142, 1);
+  stroke-width: 0.5;
+  stroke-linecap: round;
+}
+
+.board--branches .board__root-burst,
+.board--events .board__root-burst,
+.board--events .board__disease-mark,
+.board--bonus .board__sunbeam-burst,
+.board--events .board__sunbeam-burst {
+  animation: pop-fade 0.8s ease forwards;
+  animation-delay: var(--trace-delay, 0ms);
+}
+
+.board__sunbeam-burst text {
+  fill: #08111c;
+  font-size: 2.1px;
+  font-weight: 800;
+}
+
+/* Score card content */
+.score-card__head,
+.score-card__numbers,
+.panel__title-row,
+.button-row,
+.setup-grid,
+.toggle-row,
+.active-turn {
+  display: flex;
+  align-items: center;
+}
+
+.score-card__head,
+.panel__title-row,
+.button-row,
+.toggle-row {
+  justify-content: space-between;
+}
+
+.score-card__identity {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.score-card__head h2,
+.panel h1,
+.panel h2,
+.active-turn h2 {
+  margin: 0;
+  font-size: clamp(0.9rem, 2.5cqmin, 1.2rem);
+}
+
+.score-card__numbers {
+  margin-top: 0.5rem;
+  gap: 0.75rem;
+}
+
+.score-card__footer {
+  margin-top: 0.5rem;
+  padding-top: 0.4rem;
+  border-top: 1px solid rgba(255, 255, 255, 0.08);
+  color: rgba(231, 238, 247, 0.72);
+  font-size: 0.75rem;
+}
+
+.score-card__numbers div {
+  display: grid;
+  gap: 0.1rem;
+}
+
+.score-card__numbers span,
+.eyebrow,
+label span,
+.log-list p,
+.status-panel p,
+.active-turn p,
+.effect-empty {
+  color: rgba(231, 238, 247, 0.72);
+}
+
+.score-card__meta {
+  font-size: 0.75rem;
+  color: rgba(231, 238, 247, 0.7);
+}
+
+.score-card__numbers strong {
+  font-size: 1.2rem;
+}
+
+.score-value {
+  display: inline-block;
+}
+
+.score-value.changed {
+  animation: score-pop 0.7s ease;
+}
+
+.player-dot {
+  width: 0.85rem;
+  height: 0.85rem;
+  border-radius: 999px;
+  background: var(--player-color);
+  box-shadow: 0 0 16px var(--player-glow);
+}
+
+/* Sidebar content */
+.panel__actions {
+  display: flex;
+  gap: 0.5rem;
+}
+
+.eyebrow {
+  margin: 0 0 0.25rem;
+  font-size: 0.75rem;
+  letter-spacing: 0.1em;
+  text-transform: uppercase;
+}
+
+.button-row {
+  gap: 0.5rem;
+}
+
+.button-row button,
+.ghost-button {
+  min-height: 2.4rem;
+  padding: 0.5rem 0.75rem;
+  border-radius: 0.85rem;
+  background: #f4f7fb;
+  color: #0a1020;
+  font-weight: 700;
+  font-size: 0.9rem;
+  border: none;
+  cursor: pointer;
+}
+
+.ghost-button,
+#finish-game {
+  background: rgba(255, 255, 255, 0.08);
+  color: #f4f7fb;
+  border: 1px solid rgba(255, 255, 255, 0.1);
+}
+
+button:disabled {
+  opacity: 0.45;
+  cursor: not-allowed;
+}
+
+.log-list {
+  display: grid;
+  gap: 0.4rem;
+  font-size: 0.8rem;
+  overflow: auto;
+}
+
+.log-list p,
+.status-panel p,
+.active-turn p {
+  margin: 0;
+}
+
+.event-note {
+  color: #ffd577;
+}
+
+.active-turn {
+  flex-direction: column;
+  align-items: flex-start;
+  gap: 0.25rem;
+  padding: 0.6rem;
+  border-radius: 0.85rem;
+  background: linear-gradient(135deg, color-mix(in srgb, var(--player-color) 22%, rgba(255, 255, 255, 0.04)), rgba(255, 255, 255, 0.04));
+  border: 1px solid color-mix(in srgb, var(--player-color) 35%, rgba(255, 255, 255, 0.08));
+}
+
+/* Form elements */
+button,
+input,
+select {
+  font: inherit;
+}
+
+input[type="number"],
+input[type="text"],
+select {
+  width: 100%;
+  min-height: 2.4rem;
+  padding: 0.5rem 0.75rem;
+  border-radius: 0.75rem;
+  border: 1px solid rgba(255, 255, 255, 0.12);
+  background: rgba(255, 255, 255, 0.05);
+  color: #f4f7fb;
+  font-size: 0.9rem;
+}
+
+input[type="range"] {
+  width: 100%;
+}
 
 /* Modal styles */
 .modal-backdrop {