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

:root {
  --bg: #f9fafb;
  --card: #ffffff;
  --border: rgba(4, 44, 103, 0.12);
  --text: #0f172a;
  --muted: rgba(15, 23, 42, 0.65);

  --accent-1: #042c67;
  --accent-2: #1e4fa3;
  --accent-3: #93b4e8;

  --shadow: 0 18px 50px rgba(4, 44, 103, 0.18);
  --radius: 16px;
}

body {
  font-family:
    "Segoe UI",
    system-ui,
    -apple-system,
    sans-serif;
  background-color: #f9fafb;
  color: #0f172a;
  min-height: 100vh;
  margin: 0;
}

body.embed {
  background: transparent;
  min-height: 0;
}

body.embed .container {
  min-height: 0;
  padding: 12px;
  justify-content: flex-start;
  gap: 12px;
}

body.embed .calculator {
  width: 100%;
  max-width: 560px;
  margin: 0 auto;
}

body.embed .footer {
  display: none;
}

.container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;

  padding: 20px;
  gap: 16px;
}

.calculator {
  width: 100%;
  max-width: 420px;
  padding: 18px;

  border-radius: var(--radius);
  background: linear-gradient(180deg, #ffffff, rgba(4, 44, 103, 0.015));

  border: 1px solid var(--border);
  box-shadow: var(--shadow);

  transition:
    transform 0.2s ease,
    box-shadow 0.2s ease,
    border-color 0.2s ease;
}

.calculator:hover {
  transform: translateY(-2px);
  border-color: rgba(4, 44, 103, 0.18);
  box-shadow: 0 22px 60px rgba(4, 44, 103, 0.2);
}

h1 {
  font-size: 1.35rem;
  margin-bottom: 14px;
  text-align: center;
  font-weight: 800;
  letter-spacing: 0.2px;

  background: linear-gradient(90deg, var(--accent-1), var(--accent-2));

  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

label {
  display: block;
  margin-bottom: 12px;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--muted);
}

input,
select {
  width: 100%;
  padding: 11px 12px;
  margin-top: 6px;
  font-size: 1rem;

  border-radius: 12px;
  border: 1px solid var(--border);
  background: #ffffff;
  color: var(--text);

  outline: none;
  transition:
    box-shadow 0.15s ease,
    border-color 0.15s ease,
    background-color 0.15s ease;
}

input::placeholder {
  color: rgba(15, 23, 42, 0.45);
}

input:focus,
select:focus {
  border-color: rgba(4, 44, 103, 0.55);
  box-shadow: 0 0 0 4px rgba(4, 44, 103, 0.16);
}

input:hover,
select:hover {
  border-color: rgba(4, 44, 103, 0.22);
}

#calculateBtn {
  width: 100%;
  padding: 12px;
  margin-top: 14px;
  border: none;
  border-radius: 12px;

  font-size: 1rem;
  font-weight: 800;
  cursor: pointer;
  color: #fff;

  background: linear-gradient(180deg, var(--accent-2), var(--accent-1));

  box-shadow: 0 12px 28px rgba(4, 44, 103, 0.28);

  transition:
    transform 0.15s ease,
    box-shadow 0.15s ease,
    filter 0.15s ease;
}

#calculateBtn:hover {
  filter: brightness(1.03);
  box-shadow: 0 14px 34px rgba(4, 44, 103, 0.35);
  transform: translateY(-1px);
}

#calculateBtn:active {
  transform: translateY(0);
  box-shadow: 0 8px 18px rgba(4, 44, 103, 0.25);
}

#calculateBtn:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 3px rgba(255, 255, 255, 0.9),
    0 0 0 6px rgba(4, 44, 103, 0.45);
}

.reset-btn {
  width: 100%;
  padding: 12px;
  margin-top: 10px;

  border-radius: 12px;
  border: 1px solid var(--border);

  background: #ffffff;
  color: var(--accent-1);

  font-weight: 700;
  cursor: pointer;

  transition:
    background-color 0.15s ease,
    border-color 0.15s ease,
    box-shadow 0.15s ease;
}

.reset-btn:hover {
  background: rgba(4, 44, 103, 0.04);
  border-color: rgba(4, 44, 103, 0.25);
}

.reset-btn:active {
  background: rgba(4, 44, 103, 0.08);
}

.reset-btn:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 3px rgba(255, 255, 255, 0.9),
    0 0 0 6px rgba(4, 44, 103, 0.35);
}

.separator {
  margin: 16px 0;
  border: none;
  height: 1px;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(15, 23, 42, 0.14),
    transparent
  );
}

.footer {
  text-align: center;
  font-size: 0.9rem;
  color: rgba(15, 23, 42, 0.6);
  padding-top: 14px;
  border-top: 1px solid rgba(15, 23, 42, 0.08);
  width: 100%;
  max-width: 420px;
}

.footer-links {
  margin-top: 8px;
}

.footer-links a {
  margin: 0 10px;
  color: var(--accent-1);
  text-decoration: none;
  font-weight: 600;
  transition:
    color 0.15s ease,
    text-decoration-color 0.15s ease;
}

.footer-links a:hover {
  color: var(--accent-2);
  text-decoration: underline;
}

/* ===============================
   MODAL – wyniki obliczeń
   =============================== */

.modal.hidden {
  display: none;
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 999;
  display: grid;
  place-items: center;
  padding: 16px;
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(2, 6, 23, 0.55);
}

.modal-content {
  position: relative;
  z-index: 1;
  width: min(92vw, 420px);
  border-radius: 16px;
  padding: 18px;

  background: #ffffff;
  border: 1px solid rgba(4, 44, 103, 0.12);
  box-shadow: 0 24px 70px rgba(4, 44, 103, 0.18);
  animation: modalIn 0.25s ease;
}

.modal-content:focus {
  outline: none;
  box-shadow:
    0 24px 70px rgba(4, 44, 103, 0.18),
    0 0 0 4px rgba(4, 44, 103, 0.16);
}

.modal-content h2 {
  text-align: center;
  margin-bottom: 16px;
  color: var(--accent-1);
  letter-spacing: 0.2px;
}

.modal-results {
  display: grid;
  gap: 12px;
  margin-bottom: 16px;
}

.modal-results div {
  display: flex;
  justify-content: space-between;
  align-items: center;

  background: rgba(4, 44, 103, 0.03);
  border: 1px solid rgba(4, 44, 103, 0.1);
  padding: 10px 12px;
  border-radius: 12px;
}

.modal-results strong {
  color: var(--accent-1);
}

.modal-summary {
  text-align: center;
  font-weight: 500;
  margin-bottom: 16px;
  color: rgba(15, 23, 42, 0.9);
}

.modal-close {
  width: 100%;
  padding: 12px;

  border: none;
  border-radius: 12px;

  cursor: pointer;
  font-weight: 800;
  color: #fff;

  background: linear-gradient(180deg, var(--accent-2), var(--accent-1));
  box-shadow: 0 10px 24px rgba(4, 44, 103, 0.25);

  transition:
    transform 0.15s ease,
    box-shadow 0.15s ease,
    filter 0.15s ease;
}

.modal-close:hover {
  filter: brightness(1.03);
  box-shadow: 0 12px 30px rgba(4, 44, 103, 0.32);
  transform: translateY(-1px);
}

.modal-close:active {
  transform: translateY(0);
  box-shadow: 0 8px 18px rgba(4, 44, 103, 0.22);
}

.modal-close:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 3px #ffffff,
    0 0 0 6px rgba(4, 44, 103, 0.45);
}

body.modal-open {
  overflow: hidden;
}

@keyframes modalIn {
  from {
    opacity: 0;
    transform: translateY(12px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@media (max-width: 600px) {
  .calculator {
    padding: 16px;
    box-shadow: none;
    border-radius: 0;
    max-width: 100%;
  }

  h1 {
    font-size: 1.2rem;
  }

  input,
  select,
  button {
    font-size: 0.95rem;
  }

  #result {
    font-size: 0.95rem;
  }
}

@media (min-width: 601px) and (max-width: 1024px) {
  body {
    padding: 40px;
  }

  .calculator {
    max-width: 500px;
  }

  h1 {
    font-size: 1.6rem;
  }
}

@media (min-width: 1025px) {
  .calculator {
    max-width: 450px;
  }

  h1 {
    font-size: 1.8rem;
  }
}

@keyframes shake {
  0% {
    transform: translateX(0);
  }
  25% {
    transform: translateX(-6px);
  }
  50% {
    transform: translateX(6px);
  }
  75% {
    transform: translateX(-6px);
  }
  100% {
    transform: translateX(0);
  }
}

.shake {
  animation: shake 0.4s ease;
}