/* ════ SETUP ════ */
#setup-screen { background: var(--bg); animation: fadeIn .25s ease; }

.setup-body {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 32px 28px;
  text-align: center;
  overflow-y: auto;
}

.setup-icon {
  width: 68px;
  height: 68px;
  background: var(--orange-light);
  border-radius: 22px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 24px;
  color: var(--orange);
}

.setup-title { font-size: 24px; font-weight: 700; margin-bottom: 10px; }

.setup-desc {
  font-size: 15px;
  color: var(--text-dim);
  line-height: 1.65;
  max-width: 310px;
  margin: 0 auto 32px;
}

.how-card {
  background: var(--surface);
  border-radius: 16px;
  padding: 18px 20px;
  text-align: left;
  width: 100%;
  max-width: 340px;
  box-shadow: var(--btn-shadow);
  margin-bottom: 28px;
}

.how-label { font-size: 11px; font-weight: 700; letter-spacing: .07em; text-transform: uppercase; color: var(--text-dim); margin-bottom: 12px; }

.how-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 14px;
  color: var(--text);
  margin-bottom: 8px;
  line-height: 1.4;
}
.how-row:last-child { margin-bottom: 0; }

.how-dot {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--orange);
  color: white;
  font-size: 11px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 1px;
}

.inp-wrap { width: 100%; max-width: 340px; margin-bottom: 14px; }
.inp-lbl { font-size: 12px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--text-dim); margin-bottom: 8px; display: block; text-align: left; }

.inp {
  width: 100%;
  background: var(--surface);
  border: 2px solid transparent;
  border-radius: 14px;
  padding: 16px;
  font-size: 28px;
  font-family: 'Roboto', monospace;
  font-weight: 500;
  color: var(--text);
  letter-spacing: .18em;
  text-align: center;
  outline: none;
  box-shadow: var(--btn-shadow);
  transition: border-color .2s;
  -webkit-text-security: disc;
}
.inp.vis { -webkit-text-security: none; letter-spacing: .1em; }
.inp:focus { border-color: var(--orange); }

.err { font-size: 13px; color: #e05555; margin-top: 6px; min-height: 18px; }

.main-btn {
  width: 100%;
  max-width: 340px;
  padding: 18px;
  border-radius: 16px;
  background: var(--orange);
  color: white;
  font-size: 16px;
  font-weight: 700;
  border: none;
  cursor: pointer;
  box-shadow: 0 4px 16px rgba(255,122,0,.3);
  transition: background .12s, transform .1s;
  font-family: 'Roboto', sans-serif;
}
.main-btn:active { background: var(--orange-dark); transform: scale(.98); }
.main-btn:disabled { background: #ccc; box-shadow: none; cursor: default; }

/* ════ CALCULATOR ════ */
#calc-screen { background: var(--bg); animation: fadeIn .2s ease; }

.calc-display {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 0 24px 20px;
}

.disp-expr {
  text-align: right;
  font-size: 36px;
  font-weight: 400;
  color: var(--text);
  min-height: 48px;
  line-height: 1.2;
  word-break: break-all;
}

.disp-result {
  text-align: right;
  font-size: 22px;
  color: var(--text-dim);
  min-height: 30px;
  margin-top: 4px;
  font-weight: 300;
}

.calc-grid {
  padding: 10px 14px max(28px, env(safe-area-inset-bottom));
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}

.cbtn {
  all: unset;
  cursor: pointer;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--surface);
  box-shadow: var(--btn-shadow);
  font-size: 26px;
  font-weight: 400;
  color: var(--text);
  aspect-ratio: 1;
  transition: transform .08s, opacity .08s;
  position: relative;
  overflow: hidden;
}
.cbtn:active { transform: scale(.91); opacity: .8; }

.cbtn.op { color: var(--orange); font-size: 28px; }
.cbtn.fn { color: var(--text-dim); font-size: 20px; font-weight: 500; }
.cbtn.fn-icon { color: var(--orange); }

.cbtn.eq {
  background: var(--orange);
  color: white;
  font-size: 32px;
  box-shadow: 0 4px 16px rgba(255,122,0,.3), var(--btn-shadow);
}
.cbtn.eq:active { background: var(--orange-dark); }

.del-icon { width: 24px; height: 24px; color: var(--orange); }