/* =======================================
   VOLUME CALCULATOR - MODERNE STIJL
   ======================================= */

.volume-calculator-card {
  max-width: 1400px;
  margin: 0 auto;
  padding: 35px;
  background: linear-gradient(
    145deg,
    var(--card-bg) 0%,
    var(--secondary-bg) 100%
  );
  border: 1px solid var(--border-color);
  border-radius: 20px;
  box-shadow:
    0 20px 60px rgba(0, 0, 0, 0.5),
    0 0 0 1px rgba(255, 255, 255, 0.05) inset;
  color: var(--text-color);
  position: relative;
  overflow: hidden;
  box-sizing: border-box;
  font-family: 'Inter', sans-serif;
}

.volume-calculator-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(
    90deg,
    var(--accent-purple),
    var(--accent-blue),
    var(--accent-purple)
  );
  background-size: 200% 100%;
  animation: volumeGradientShift 3s ease infinite;
}

@keyframes volumeGradientShift {
  0%, 100% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
}

.volume-calculator-card h1 {
  color: var(--text-primary);
  font-size: 2rem;
  margin-bottom: 8px;
  text-align: center;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.volume-calculator-card .intro {
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 25px;
  font-weight: 400;
  line-height: 1.6;
}

/* =======================================
   SHAPE SELECTOR
   ======================================= */

.volume-calculator-selector {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 15px;
  margin-bottom: 30px;
  padding: 20px;
  background: var(--overlay-medium);
  border-radius: 12px;
  border: 1px solid rgba(45, 55, 72, 0.5);
}

.volume-calculator-shape-btn {
  padding: 16px 12px;
  border: 2px solid var(--border-dark);
  border-radius: 12px;
  background: var(--overlay-dark);
  color: var(--text-color);
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 0.9rem;
}

.volume-calculator-shape-btn:hover {
  border-color: var(--accent-purple);
  transform: translateY(-2px);
  box-shadow: 0 4px 15px rgba(147, 51, 234, 0.3);
}

.volume-calculator-shape-btn.active {
  border-color: var(--accent-purple);
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-blue) 100%);
  color: white;
  box-shadow: 0 4px 20px rgba(147, 51, 234, 0.5);
}

.volume-calculator-shape-icon {
  font-size: 2rem;
}

.volume-calculator-shape-name {
  font-size: 0.85rem;
}

/* =======================================
   SHAPE CONTAINERS
   ======================================= */

.volume-calculator-shape-container {
  display: none;
  background: var(--overlay-medium);
  border: 1px solid rgba(45, 55, 72, 0.5);
  border-radius: 12px;
  padding: 25px;
  margin-bottom: 30px;
}

.volume-calculator-shape-container.active {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 25px;
  align-items: start;
}

.volume-calculator-shape-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 25px;
  background: var(--overlay-dark);
  border-radius: 12px;
  border: 1px solid var(--border-dark);
  height: 100%;
}

.volume-calculator-shape-svg {
  width: 100%;
  max-width: 250px;
  height: auto;
}

.volume-calculator-shape-right {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* =======================================
   INPUTS SECTION
   ======================================= */

.volume-calculator-shape-inputs {
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.volume-calculator-input-group {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.volume-calculator-input-group label {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 8px;
}

/* INPUT WRAPPER met pijltjes */
.volume-calculator-input-with-unit {
  display: flex;
  align-items: center;
  background: var(--overlay-dark);
  border: 2px solid var(--border-dark);
  border-radius: 12px;
  overflow: hidden;
  height: 56px;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
  position: relative;
}

.volume-calculator-input-with-unit:focus-within {
  border-color: var(--accent-purple);
  box-shadow: 0 0 20px rgba(147, 51, 234, 0.2);
}

.volume-calculator-input-group input {
  flex-grow: 1;
  border: none;
  background: transparent;
  text-align: center;
  font-size: 1.1rem;
  padding: 0 15px;
  height: 100%;
  color: var(--text-primary);
  font-weight: 600;
  font-family: "Roboto Mono", monospace;
  outline: none;
  box-sizing: border-box;
}

.volume-calculator-input-group input::-webkit-inner-spin-button,
.volume-calculator-input-group input::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.volume-calculator-input-group input {
  -moz-appearance: textfield;
}

.volume-calculator-input-group input::placeholder {
  color: var(--text-secondary);
  opacity: 0.5;
  font-weight: 400;
}

.volume-calculator-unit {
  padding-right: 15px;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  white-space: nowrap;
}

/* =======================================
   FORMULA SECTION
   ======================================= */

.volume-calculator-shape-formula {
  padding: 16px 20px;
  background: var(--overlay-dark);
  border: 1px solid var(--border-dark);
  border-radius: 10px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  text-align: center;
}

.volume-calculator-shape-formula strong {
  color: var(--accent-blue);
  font-weight: 700;
  margin-right: 8px;
}

/* =======================================
   RESULT SECTION
   ======================================= */

.volume-calculator-result {
  background: var(--overlay-medium);
  border: 2px solid var(--accent-purple);
  border-radius: 12px;
  padding: 25px;
  margin-bottom: 25px;
}

.volume-calculator-result-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.volume-calculator-result-label {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.volume-calculator-result-value {
  font-family: "Roboto Mono", monospace;
  font-size: 2.2rem;
  font-weight: 700;
  color: var(--accent-purple);
}

/* =======================================
   BUTTONS
   ======================================= */

.volume-calculator-actions {
  text-align: center;
  margin-bottom: 20px;
}

.volume-calculator-reset-btn {
  padding: 14px 25px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-weight: 600;
  font-size: 1rem;
  transition: all 0.2s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  position: relative;
  overflow: hidden;
  color: white;
  background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
  box-shadow: 0 4px 15px rgba(239, 68, 68, 0.4);
}

.volume-calculator-reset-btn::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.2);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

.volume-calculator-reset-btn:hover::before {
  width: 300px;
  height: 300px;
}

.volume-calculator-reset-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(239, 68, 68, 0.6);
}

.volume-calculator-reset-btn:active {
  transform: translateY(0);
}

/* =======================================
   NOTE SECTION
   ======================================= */

.volume-calculator-note {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-secondary);
  padding: 12px;
  background: var(--overlay-dark);
  border-radius: 10px;
  border: 1px solid var(--border-dark);
}

.volume-calculator-note small {
  display: block;
}

/* =======================================
   RESPONSIVE
   ======================================= */

@media (max-width: 899px) {
  .volume-calculator-card {
    padding: 20px 12px;
  }

  .volume-calculator-card h1 {
    font-size: 1.5rem;
  }

  .volume-calculator-card .intro {
    font-size: 0.85rem;
  }

  .volume-calculator-selector {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    padding: 15px;
  }

  .volume-calculator-shape-btn {
    padding: 12px 8px;
  }

  .volume-calculator-shape-icon {
    font-size: 1.6rem;
  }

  .volume-calculator-shape-name {
    font-size: 0.8rem;
  }

  .volume-calculator-shape-container {
    padding: 15px;
  }

  .volume-calculator-shape-container.active {
    grid-template-columns: 1fr;
    gap: 15px;
  }

  .volume-calculator-shape-visual {
    padding: 15px;
  }

  .volume-calculator-shape-svg {
    max-width: 180px;
  }

  .volume-calculator-input-with-unit {
    height: 50px;
  }

  .volume-calculator-result-value {
    font-size: 1.8rem;
  }
}

@media (max-width: 480px) {
  .volume-calculator-card {
    padding: 15px 10px;
  }

  .volume-calculator-card h1 {
    font-size: 1.3rem;
  }

  .volume-calculator-input-with-unit {
    height: 48px;
  }

  .volume-calculator-result-value {
    font-size: 1.5rem;
  }
}