* {
  box-sizing: border-box;
}
html, body{
  width: 100%;
  max-width: 100%;
  overflow-x: hidden;
}

body {
  margin: 0;
  font-family: "Poppins", sans-serif;
  background: linear-gradient(180deg, #cfeaff, #e9f6ff);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 25px;
}

/* Card */
.card {
  width: 100%;
  max-width: 420px;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  border-radius: 22px;
  padding: 20px;
  box-shadow: 0 12px 35px rgba(90, 160, 210, 0.35);
}

/* Tabs */
.tabs {
  position: relative;
  display: flex;
  gap: 10px;
  background: rgba(210, 238, 255, 0.65);
  border-radius: 999px;
  padding: 10px;
  overflow: hidden;
  margin-bottom: 18px;
}

.tab-btn {
  flex: 1;
  border: none;
  background: transparent;
  font-weight: 700;
  color: #145a86;
  padding: 12px 10px;
  border-radius: 999px;
  cursor: pointer;
  z-index: 2;
  font-size: 14px;
}

.pill-bg {
  position: absolute;
  top: 10px;
  left: 10px;
  width: calc(50% - 5px);
  height: calc(100% - 20px);
  background: linear-gradient(90deg, #7fc8ff, #9ee0ff);
  border-radius: 999px;
  transition: all 0.35s ease;
  box-shadow: 0 6px 16px rgba(0, 120, 255, 0.25);
  z-index: 1;
}

/* Slider */
.slider {
  overflow: hidden;
  width: 100%;
}

.slider-inner {
  display: flex;
  width: 200%;
  transition: transform 0.4s ease;
}

.tab-panel {
  width: 50%;
  padding: 10px;
}

h1 {
  text-align: center;
  font-size: 34px;
  margin: 10px 0 5px;
  font-weight: 800;
  color: #2d6f9f;
}

.desc {
  text-align: center;
  font-size: 14px;
  margin-bottom: 18px;
  color: #3b7aa2;
}

/* Form */
label {
  display: block;
  margin-bottom: 12px;
  font-weight: 600;
  color: #1c4d6d;
  font-size: 15px;
}

input {
  width: 100%;
  padding: 12px 14px;
  margin-top: 6px;
  border-radius: 14px;
  border: 2px solid rgba(130, 200, 255, 0.35);
  outline: none;
  font-size: 15px;
  font-family: "Poppins", sans-serif;
  background: rgba(255, 255, 255, 0.75);
  transition: 0.2s;
}

input:focus {
  border-color: rgba(70, 160, 255, 0.6);
  box-shadow: 0 4px 12px rgba(70, 160, 255, 0.2);
}

/* Buttons */
.btn {
  width: 100%;
  margin-top: 12px;
  padding: 14px;
  border: none;
  border-radius: 18px;
  background: linear-gradient(90deg, #7fc8ff, #9ee0ff);
  color: #0c3b55;
  font-weight: 800;
  font-size: 15px;
  cursor: pointer;
  box-shadow: 0 8px 20px rgba(80, 150, 220, 0.25);
  transition: 0.2s;
}

.btn:active {
  transform: scale(0.98);
}

.hasil {
  margin-top: 18px;
  padding-top: 18px;
  border-top: 2px solid rgba(130, 200, 255, 0.35);
  text-align: center;
}

.hasil h2 {
  margin: 0 0 8px;
  font-size: 22px;
  font-weight: 800;
  color: #0b2d44;
}

#output,
#outputHari {
  display: inline-block;
  font-size: 26px;
  font-weight: 800;
  color: #004a7f;
  background: rgba(159, 210, 255, 0.35);
  padding: 10px 18px;
  border-radius: 16px;
  box-shadow: 0 6px 14px rgba(0, 0, 0, 0.06);
  margin: 10px auto 0;
}

.rumus {
  font-size: 13px;
  color: #336a88;
  margin: 14px 0 14px;
  line-height: 1.4;
}

.btn-row {
  display: flex;
  gap: 10px;
  margin-top: 10px;
}

.btn2 {
  flex: 1;
  padding: 12px;
  border-radius: 14px;
  border: none;
  background: linear-gradient(90deg, #7fc8ff, #9ee0ff);
  color: #003a64;
  font-weight: 800;
  cursor: pointer;
  box-shadow: 0 3px 8px rgba(0, 0, 0, 0.08);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.btn2:active {
  opacity: 0.85;
  transform: scale(0.97);
}

.detail {
  margin-top: 10px;
  font-size: 13px;
  color: #2e5d78;
  line-height: 1.45;
}

/* Credit */
.credit {
  margin-top: 14px;
  font-size: 12px;
  color: #327ab7;
  opacity: 0.9;
}

.credit-link {
  text-decoration: none;
  font-weight: 800;
  color: #145a86;
}

.credit-link:active {
  opacity: 0.7;
}

/* Fix khusus input tanggal biar ga nyambung & lengkungan normal */
input[type="date"]{
  appearance: none;
  -webkit-appearance: none;
  background-color: #fff;
  border-radius: 16px !important;
  border: 2px solid rgba(0, 140, 255, 0.18) !important;
  padding: 14px 16px !important;
  font-size: 16px;
  outline: none;
  box-shadow: none !important;
}

/* saat klik/focus biar rapih */
input[type="date"]:focus{
  border-color: rgba(0, 140, 255, 0.35) !important;
  box-shadow: 0 0 0 4px rgba(0, 140, 255, 0.10) !important;
}