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

:root {
  --bg-deep: #e8f4f2;
  --bg-panel: #ffffff;
  --bg-sidebar: #f4faf9;
  --bg-input: #ffffff;

  --border-subtle: rgba(95, 182, 170, 0.22);
  --border-strong: rgba(95, 182, 170, 0.42);

  --text: #1b3a37;
  --text-muted: #5a7d79;

  --accent: #5fb6aa;
  --accent-dark: #469c91;
  --accent-soft: rgba(95, 182, 170, 0.16);

  --pink-border: rgba(214, 138, 150, 0.42);
  --pink-deep: #ad6e7a;

  --canvas-shadow: 0 12px 32px rgba(24, 49, 47, 0.09);

  --radius: 12px;
  --radius-sm: 8px;

  --font: "Plus Jakarta Sans", system-ui, -apple-system, sans-serif;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font);
  font-size: 14px;
  line-height: 1.5;
  background: var(--bg-deep);
  background-image:
    radial-gradient(ellipse 100% 70% at 50% -15%, rgba(95, 182, 170, 0.14), transparent 55%),
    radial-gradient(ellipse 70% 45% at 100% 100%, rgba(243, 199, 208, 0.12), transparent 50%);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
}

.app {
  max-width: 1280px;
  margin: 0 auto;
  padding: 20px 20px 24px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.app-header {
  text-align: center;
  margin-bottom: 20px;
  flex-shrink: 0;
}

.app-title {
  margin: 0;
  font-size: clamp(1.55rem, 4vw, 2.05rem);
  font-weight: 700;
  letter-spacing: 0.05em;
  color: #17403c;
}

.app-credits {
  margin-top: auto;
  padding-top: 32px;
  padding-bottom: 10px;
  text-align: center;
  flex-shrink: 0;
}

.app-credits__line {
  margin: 0;
  font-size: 12px;
  color: #3e6f6a;
  font-weight: 600;
  letter-spacing: 0.04em;
}

.app-credits__line + .app-credits__line {
  margin-top: 6px;
}

.app-credits__author {
  font-weight: 600;
  color: var(--pink-deep);
}

.app-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 18px;
  align-items: start;
  flex: 1;
  min-height: 0;
}

.workspace {
  display: flex;
  flex-direction: column;
  min-width: 0;
  gap: 12px;
}

.top-tools {
  flex-shrink: 0;
}

.top-tools .hint {
  display: block;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--text-muted);
  margin-bottom: 8px;
  line-height: 1.4;
}

.btn-row {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 8px;
}

.tool-btn {
  padding: 8px 10px;
  min-height: 36px;
  border-radius: 999px;
  border: 1px solid var(--border-subtle);
  background: linear-gradient(180deg, #ffffff, #f0faf8);
  color: var(--text);
  font-family: inherit;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: background 0.18s, border-color 0.18s, box-shadow 0.18s, transform 0.06s;
  text-align: center;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 1px 2px rgba(24, 49, 47, 0.04);
}

.tool-btn:hover {
  background: linear-gradient(180deg, #ffffff, #e8f6f3);
  border-color: var(--border-strong);
}

.tool-btn.active {
  background: linear-gradient(180deg, #7ccbc0, var(--accent));
  border-color: rgba(70, 156, 145, 0.55);
  color: #fff;
  box-shadow: 0 2px 8px rgba(70, 156, 145, 0.28);
}

.canvas-wrap {
  position: relative;
  flex: 1;
  min-height: 560px;
  background: #fff;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--canvas-shadow);
  border: 1px solid rgba(95, 182, 170, 0.15);
}

.canvas-toolbar {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  z-index: 2;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
  padding: 8px 10px;
  pointer-events: none;
  background: linear-gradient(to bottom, rgba(255, 255, 255, 0.95), rgba(255, 255, 255, 0.5), transparent);
}

.canvas-toolbar .canvas-icon-btn {
  pointer-events: auto;
}

.canvas-icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  height: 32px;
  padding: 0 8px;
  border: 1px solid var(--pink-border);
  border-radius: 999px;
  background: linear-gradient(180deg, #fce8ec, #f3c7d0);
  color: #6b343e;
  font-family: inherit;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(107, 52, 62, 0.1);
  transition: background 0.18s, border-color 0.18s, transform 0.08s, box-shadow 0.18s;
}

.canvas-icon-btn:hover:not(:disabled) {
  background: linear-gradient(180deg, #f8d8df, #e8a9b7);
  border-color: rgba(214, 138, 150, 0.65);
  box-shadow: 0 2px 10px rgba(107, 52, 62, 0.14);
}

.canvas-icon-btn:active:not(:disabled) {
  transform: scale(0.96);
}

.canvas-icon-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.canvas-icon-btn__glyph {
  font-size: 18px;
  line-height: 1;
  color: #6b343e;
}

#canvas {
  display: block;
  width: 100%;
  height: 100%;
  vertical-align: middle;
  cursor: crosshair;
  touch-action: none;
}

.canvas-label {
  position: absolute;
  left: 12px;
  bottom: 8px;
  z-index: 1;
  font-size: 10px;
  font-weight: 500;
  letter-spacing: 0.07em;
  color: #c5cad3;
  pointer-events: none;
}

.bottom-tools {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-shrink: 0;
}

.tool-btn.wide {
  flex: 1;
  min-height: 40px;
  font-size: 12px;
}

.tool-btn.secondary {
  background: linear-gradient(180deg, #fce8ec, #f3c7d0);
  border-color: var(--pink-border);
  color: #6b343e;
}

.tool-btn.secondary:hover {
  background: linear-gradient(180deg, #f8d8df, #e8a9b7);
  border-color: rgba(214, 138, 150, 0.65);
  box-shadow: 0 2px 10px rgba(107, 52, 62, 0.12);
}

.tool-btn.secondary:active {
  transform: scale(0.99);
}

.sidebar {
  background: var(--bg-sidebar);
  border-radius: var(--radius);
  padding: 16px 16px 18px;
  border: 1px solid var(--border-subtle);
  box-shadow: 0 8px 28px rgba(24, 49, 47, 0.08);
  overflow-y: auto;
  overflow-x: hidden;
  align-self: start;
  max-height: calc(100vh - 40px);
}

.sidebar-title {
  margin: 0 0 6px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--text);
}

.sidebar-note {
  font-size: 11px;
  font-weight: 500;
  color: var(--text-muted);
  margin: 0 0 14px;
  line-height: 1.4;
}

.sidebar-note--plain {
  letter-spacing: 0.01em;
}

.panel-block {
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border-subtle);
}

.panel-block:last-of-type {
  border-bottom: none;
  margin-bottom: 0;
  padding-bottom: 0;
}

.panel-block h3 {
  margin: 0 0 8px;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  font-weight: 700;
  color: #244744;
}

.panel-block h3::after {
  content: "";
  display: block;
  width: 28px;
  height: 2px;
  margin-top: 5px;
  background: linear-gradient(90deg, var(--accent), rgba(95, 182, 170, 0.35));
  border-radius: 2px;
}

.field-label {
  display: block;
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  margin-top: 8px;
  margin-bottom: 4px;
}

.field-label:first-of-type {
  margin-top: 0;
}

.num-input {
  width: 100%;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  background: #ffffff;
  color: var(--text);
  font-family: inherit;
  font-size: 13px;
  font-weight: 500;
  transition: border-color 0.15s, box-shadow 0.15s;
}

.num-input--block {
  display: block;
}

.num-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

.btn-apply {
  width: 100%;
  padding: 9px 12px;
  margin-top: 10px;
  border: none;
  border-radius: var(--radius-sm);
  background: linear-gradient(180deg, #7ccbc0, var(--accent));
  color: #ffffff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.15);
  font-family: inherit;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.04em;
  cursor: pointer;
  text-transform: capitalize;
  transition: filter 0.15s, transform 0.06s, box-shadow 0.15s;
  box-shadow: 0 2px 8px rgba(70, 156, 145, 0.22);
}

.btn-apply:hover {
  filter: brightness(1.05);
}

.btn-apply:active {
  transform: scale(0.99);
  filter: brightness(0.97);
}

.btn-refl {
  width: 100%;
  padding: 9px 12px;
  margin-top: 6px;
  border: none;
  border-radius: var(--radius-sm);
  background: linear-gradient(180deg, #7ccbc0, var(--accent));
  color: #ffffff;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.15);
  font-family: inherit;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.04em;
  cursor: pointer;
  text-transform: capitalize;
  transition: filter 0.15s, transform 0.06s;
  box-shadow: 0 2px 8px rgba(70, 156, 145, 0.2);
}

.btn-refl:first-of-type {
  margin-top: 0;
}

.btn-refl:hover {
  filter: brightness(1.05);
}

.btn-refl:active {
  transform: scale(0.99);
}

@media (max-width: 960px) {
  .app-grid {
    grid-template-columns: 1fr;
  }

  .sidebar {
    max-height: none;
    order: 2;
  }

  .workspace {
    order: 1;
  }

  .btn-row {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 520px) {
  .btn-row {
    grid-template-columns: 1fr;
  }
}