* {
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, sans-serif;
}

body {
  margin: 0;
  min-height: 100vh;
  background: radial-gradient(circle at top, #7c3aed, #2e1065);
}

.wrapper {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
}

.card {
  background: #ffffff;
  width: 100%;
  max-width: 420px;
  padding: 32px 28px;
  border-radius: 20px;
  box-shadow: 0 25px 60px rgba(0,0,0,.35);
}

.logo {
  width: 100px;
  display: block;
  margin: 0 auto 12px;
}

h1 {
  text-align: center;
  margin: 8px 0 6px;
  color: #2e1065;
}

.desc {
  text-align: center;
  color: #555;
  margin-bottom: 22px;
  font-size: 14px;
}

label {
  font-size: 13px;
  font-weight: 600;
  margin-top: 14px;
  display: block;
  color: #333;
}

input {
  width: 100%;
  padding: 12px 14px;
  margin-top: 6px;
  border-radius: 12px;
  border: 1px solid #ddd;
  outline: none;
  font-size: 14px;
}

input:focus {
  border-color: #7c3aed;
}

button {
  width: 100%;
  margin-top: 22px;
  padding: 14px;
  border-radius: 14px;
  border: none;
  background: linear-gradient(135deg, #7c3aed, #9333ea);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
}

button:hover {
  filter: brightness(1.05);
}

#result {
  margin-top: 22px;
}

.success {
  background: #f5f3ff;
  border: 1px solid #ddd6fe;
  padding: 14px;
  border-radius: 12px;
  font-size: 14px;
}

.success a {
  display: block;
  margin-top: 6px;
  font-weight: 700;
  color: #5b21b6;
  word-break: break-all;
}
/* ================= INTRO ================= */

#intro {
  position: fixed;
  inset: 0;
  z-index: 99999;
  background: radial-gradient(circle at center, #020617, #000);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

/* LOGO */
.intro-logo {
  width: 260px;
  max-width: 80vw;
  z-index: 2;

  transform-style: preserve-3d;
  animation: logoIdle 1.2s ease-in-out infinite alternate;

  filter:
    drop-shadow(0 0 8px rgba(255,200,80,.6))
    drop-shadow(0 0 25px rgba(255,150,0,.8))
    drop-shadow(0 0 55px rgba(255,120,0,.6));
}

/* Logo đập + xoay nhẹ */
@keyframes logoIdle {
  from {
    transform: scale(1) rotateX(0deg) rotateY(0deg);
    opacity: .9;
  }
  to {
    transform: scale(1.08) rotateX(6deg) rotateY(-8deg);
    opacity: 1;
  }
}

/* FLASH NỔ */
.flash {
  position: absolute;
  inset: 0;
  background: radial-gradient(circle, #fff 0%, transparent 60%);
  opacity: 0;
  z-index: 3;
}

/* Khi nổ */
.explode .intro-logo {
  animation: logoExplode .5s ease forwards;
}

.explode .flash {
  animation: flashExplode .6s ease forwards;
}

/* Logo bay + tan */
@keyframes logoExplode {
  to {
    transform: scale(3) rotateY(35deg);
    opacity: 0;
    filter: blur(2px)
      drop-shadow(0 0 120px rgba(255,200,120,1));
  }
}

/* Flash trắng */
@keyframes flashExplode {
  0% { opacity: 0; }
  30% { opacity: 1; }
  100% { opacity: 0; }
}

/* Kết thúc intro */
.intro-end {
  animation: introFade .8s ease forwards;
}

@keyframes introFade {
  to {
    opacity: 0;
  }
}

/* ================= DEMO CONTENT ================= */

.wrapper {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.card {
  background: #fff;
  padding: 40px;
  border-radius: 20px;
}