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

:root {
  --bg-gradient-start: #0a0a0a;
  --bg-gradient-end: #000000;
  --card-bg: rgba(0, 0, 0, 0.6);
  --card-border: rgba(102, 255, 102, 0.3);
  --text-primary: #66ff66;
  --text-secondary: rgba(102, 255, 102, 0.7);
  --input-bg: rgba(0, 0, 0, 0.7);
  --input-border: rgba(102, 255, 102, 0.4);
  --input-focus: rgba(102, 255, 102, 0.6);
  --primary: #66ff66;
  --primary-hover: #7fff7f;
  --success: #66ff66;
  --danger: #ff0000;
  --warning: #ffaa00;
  --shadow: 0 8px 32px rgba(102, 255, 102, 0.2);
  --shadow-lg: 0 12px 48px rgba(102, 255, 102, 0.3);
}

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background: linear-gradient(135deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
  background-attachment: fixed;
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  position: relative;
}

/* Canvas cho hiệu ứng code bay bay */
#code-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
  opacity: 0.4;
  transition: opacity 0.3s ease;
}

.container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 40px 20px;
  position: relative;
  z-index: 1;
}

/* Logo Header */
.logo-header {
  text-align: center;
  margin-bottom: 30px;
  animation: fadeInDown 0.6s ease-out;
  position: relative;
}

.logo-text {
  font-size: 36px;
  font-weight: 800;
  letter-spacing: 3px;
  margin: 0;
  display: inline-block;
  position: relative;
  font-family: 'Segoe UI', 'Roboto', 'Arial', sans-serif;
  text-transform: uppercase;
  font-stretch: condensed;
  line-height: 1.2;
  background: linear-gradient(135deg, #00d4ff 0%, #00ff88 25%, #00d4ff 50%, #0088ff 75%, #00d4ff 100%);
  background-size: 200% auto;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  animation: gradientShift 3s ease infinite;
  filter: drop-shadow(0 0 8px rgba(0, 212, 255, 0.8)) 
          drop-shadow(0 0 16px rgba(0, 255, 136, 0.6)) 
          drop-shadow(0 0 24px rgba(0, 136, 255, 0.4));
}

.logo-text::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, #00d4ff, transparent);
  box-shadow: 0 0 10px #00d4ff;
  animation: shimmer 3s infinite;
}

/* Language Selector */
.language-selector {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 20px;
  flex-wrap: wrap;
}

.lang-btn {
  background: rgba(0, 0, 0, 0.6);
  border: 1px solid rgba(102, 255, 102, 0.4);
  border-radius: 8px;
  padding: 8px 16px;
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  font-family: 'Courier New', monospace;
  min-width: 50px;
}

.lang-btn:hover {
  border-color: #66ff66;
  color: #66ff66;
  background: rgba(102, 255, 102, 0.1);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(102, 255, 102, 0.3);
}

.lang-btn.active {
  background: rgba(102, 255, 102, 0.2);
  border-color: #66ff66;
  color: #66ff66;
  box-shadow: 0 0 10px rgba(102, 255, 102, 0.4);
}

/* Main Content */
.main-content {
  width: 100%;
  max-width: 500px;
  animation: fadeInUp 0.6s ease-out;
}

.check-card {
  background: rgba(0, 0, 0, 0.8);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(102, 255, 102, 0.4);
  border-radius: 20px;
  padding: 40px 30px;
  box-shadow: 0 0 20px rgba(102, 255, 102, 0.3), var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.check-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, #66ff66, transparent);
  box-shadow: 0 0 10px #66ff66;
  animation: shimmer 3s infinite;
}

.card-title {
  font-size: 42px;
  font-weight: 700;
  letter-spacing: 4px;
  text-transform: uppercase;
  color: #00d4ff;
  text-shadow: 0 0 10px #00d4ff, 0 0 20px #00d4ff, 0 0 30px #00d4ff;
  margin: 0 0 30px 0;
  text-align: center;
  animation: fadeInDown 0.6s ease-out;
  font-family: 'Courier New', monospace;
}

/* Form */
.check-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form-field {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.input-label {
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}

.input-group {
  position: relative;
  display: flex;
  align-items: center;
  background: var(--input-bg);
  border: 1px solid var(--input-border);
  border-radius: 12px;
  padding: 0 15px;
  transition: all 0.3s ease;
}

.input-group:focus-within {
  border-color: #66ff66;
  box-shadow: 0 0 0 3px rgba(102, 255, 102, 0.2), 0 0 10px rgba(102, 255, 102, 0.3);
  background: rgba(0, 0, 0, 0.8);
}

.input-icon {
  color: var(--text-secondary);
  font-size: 18px;
  margin-right: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
}

.form-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-size: 14px;
  padding: 16px 0;
  font-weight: 500;
}

.form-input::placeholder {
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-size: 12px;
}

/* Submit Button */
.submit-btn {
  background: rgba(102, 255, 102, 0.1);
  border: 2px solid #66ff66;
  border-radius: 12px;
  padding: 18px 24px;
  color: #66ff66;
  font-size: 16px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 0 15px rgba(102, 255, 102, 0.4), inset 0 0 15px rgba(102, 255, 102, 0.1);
  position: relative;
  overflow: hidden;
  margin-top: 10px;
  font-family: 'Courier New', monospace;
  text-shadow: 0 0 10px #66ff66;
}

.submit-btn::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(102, 255, 102, 0.3), transparent);
  transition: left 0.5s ease;
}

.submit-btn:hover::before {
  left: 100%;
}

.submit-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 0 25px rgba(102, 255, 102, 0.6), inset 0 0 20px rgba(102, 255, 102, 0.2);
  background: rgba(102, 255, 102, 0.2);
}

.submit-btn:active:not(:disabled) {
  transform: translateY(0);
}

.submit-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* Social Icons */
.social-icons {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-top: 20px;
  padding-top: 20px;
  border-top: 1px solid var(--card-border);
}

.social-icon {
  width: 45px;
  height: 45px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
  font-size: 20px;
  text-decoration: none;
  transition: all 0.3s ease;
  border: 2px solid var(--input-border);
  background: var(--input-bg);
}

.social-icon:hover {
  transform: translateY(-3px) scale(1.1);
  border-color: var(--primary);
  box-shadow: 0 4px 15px rgba(0, 212, 255, 0.3);
}

.telegram-icon:hover {
  background: #0088cc;
  border-color: #0088cc;
}

.zalo-icon:hover {
  background: #0068ff;
  border-color: #0068ff;
}

/* Result Box */
.result-box {
  margin-top: 20px;
  padding: 16px 20px;
  border-radius: 12px;
  border: 1px solid var(--card-border);
  background: rgba(0, 0, 0, 0.2);
  color: var(--text-secondary);
  font-size: 14px;
  min-height: 50px;
  display: flex;
  align-items: center;
  text-align: center;
  justify-content: center;
  transition: all 0.3s ease;
}

.result-box:empty {
  display: none;
}

.result-box.success {
  color: var(--success);
  background: rgba(0, 255, 136, 0.1);
  border-color: var(--success);
}

.result-box.error {
  color: var(--danger);
  background: rgba(255, 68, 68, 0.1);
  border-color: var(--danger);
}

.result-box.warning {
  color: var(--warning);
  background: rgba(255, 170, 0, 0.1);
  border-color: var(--warning);
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1000;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal.active {
  display: flex;
  animation: fadeIn 0.3s ease;
}

.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(3px);
}

/* Khi cảnh báo hiển thị, overlay thành màu đỏ */
.warning-modal .modal-overlay {
  background: rgba(255, 0, 0, 0.7) !important;
  backdrop-filter: blur(5px);
}

/* Khi cảnh báo: các nút và viền thành màu đỏ, nền giữ bình thường */
body.warning-active .submit-btn {
  border-color: #ff0000 !important;
  color: #ff0000 !important;
  box-shadow: 0 0 15px rgba(255, 0, 0, 0.4), inset 0 0 15px rgba(255, 0, 0, 0.1) !important;
  text-shadow: 0 0 10px #ff0000 !important;
}

body.warning-active .submit-btn::before {
  background: linear-gradient(90deg, transparent, rgba(255, 0, 0, 0.3), transparent) !important;
}

body.warning-active .submit-btn:hover:not(:disabled) {
  box-shadow: 0 0 25px rgba(255, 0, 0, 0.6), inset 0 0 20px rgba(255, 0, 0, 0.2) !important;
  background: rgba(255, 0, 0, 0.2) !important;
}

body.warning-active .activate-btn {
  border-color: #ff0000 !important;
  color: #ff0000 !important;
  box-shadow: 0 0 15px rgba(255, 0, 0, 0.4), inset 0 0 15px rgba(255, 0, 0, 0.1) !important;
  text-shadow: 0 0 10px #ff0000 !important;
}

body.warning-active .activate-btn:hover:not(:disabled) {
  box-shadow: 0 0 25px rgba(255, 0, 0, 0.6), inset 0 0 20px rgba(255, 0, 0, 0.2) !important;
  background: rgba(255, 0, 0, 0.2) !important;
}

body.warning-active .result-close-btn {
  border-color: #ff0000 !important;
  color: #ff0000 !important;
  box-shadow: 0 0 15px rgba(255, 0, 0, 0.4), inset 0 0 15px rgba(255, 0, 0, 0.1) !important;
  text-shadow: 0 0 10px #ff0000 !important;
}

body.warning-active .result-close-btn:hover {
  box-shadow: 0 0 25px rgba(255, 0, 0, 0.6), inset 0 0 20px rgba(255, 0, 0, 0.2) !important;
  background: rgba(255, 0, 0, 0.2) !important;
}

/* Viền input và card thành đỏ khi cảnh báo */
body.warning-active .input-group {
  border-color: #ff0000 !important;
}

body.warning-active .input-group:focus-within {
  border-color: #ff0000 !important;
  box-shadow: 0 0 0 3px rgba(255, 0, 0, 0.2), 0 0 10px rgba(255, 0, 0, 0.3) !important;
}

body.warning-active .check-card {
  border-color: rgba(255, 0, 0, 0.4) !important;
  box-shadow: 0 0 20px rgba(255, 0, 0, 0.3), var(--shadow-lg) !important;
}

body.warning-active .check-card::before {
  background: linear-gradient(90deg, transparent, #ff0000, transparent) !important;
  box-shadow: 0 0 10px #ff0000 !important;
}

.modal-content {
  position: relative;
  background: rgba(0, 0, 0, 0.95);
  backdrop-filter: blur(20px);
  border: 2px solid rgba(102, 255, 102, 0.4);
  border-radius: 20px;
  padding: 30px;
  max-width: 400px;
  width: 100%;
  box-shadow: 0 0 30px rgba(102, 255, 102, 0.4), var(--shadow-lg);
  z-index: 1001;
  animation: slideUp 0.3s ease;
}

/* Viền modal màu đỏ khi cảnh báo */
.warning-modal .modal-content,
.warning-modal .result-modal-content {
  border-color: #ff0000 !important;
  box-shadow: 0 0 30px rgba(255, 0, 0, 0.4), var(--shadow-lg) !important;
}

/* Viền modal màu xanh khi hoàn thành */
.success-modal .modal-content,
.success-modal .result-modal-content {
  border-color: #66ff66 !important;
  box-shadow: 0 0 30px rgba(102, 255, 102, 0.4), var(--shadow-lg) !important;
}

.modal-header {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 25px;
  position: relative;
}

.modal-title-main {
  font-size: 36px;
  font-weight: 700;
  letter-spacing: 4px;
  text-transform: uppercase;
  color: #00d4ff;
  text-shadow: 0 0 10px #00d4ff, 0 0 20px #00d4ff, 0 0 30px #00d4ff;
  margin: 0 0 10px 0;
  text-align: center;
  font-family: 'Courier New', monospace;
}

.modal-title-sub {
  font-size: 18px;
  font-weight: 600;
  color: var(--text-secondary);
  margin: 0;
  text-align: center;
}

.modal-header .modal-close {
  position: absolute;
  top: 0;
  right: 0;
}

.modal-close {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 24px;
  cursor: pointer;
  padding: 5px;
  transition: color 0.3s ease;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
}

.modal-close:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.1);
}

.modal-body {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

/* Modal Result Box */
.modal-result {
  padding: 12px 16px;
  border-radius: 10px;
  border: 1px solid var(--card-border);
  background: rgba(0, 0, 0, 0.2);
  color: var(--text-secondary);
  font-size: 13px;
  min-height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  transition: all 0.3s ease;
  position: relative;
}

.modal-result.loading::after {
  content: "";
  display: inline-block;
  width: 12px;
  height: 12px;
  border: 2px solid var(--text-secondary);
  border-top-color: transparent;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin-left: 8px;
}

.modal-result:empty {
  display: none;
}

.modal-result.error {
  color: var(--danger);
  background: rgba(255, 68, 68, 0.15);
  border-color: var(--danger);
}

.modal-result.success {
  color: var(--success);
  background: rgba(0, 255, 136, 0.15);
  border-color: var(--success);
}

.modal-result.warning {
  color: var(--warning);
  background: rgba(255, 170, 0, 0.15);
  border-color: var(--warning);
}

.activate-btn {
  background: rgba(102, 255, 102, 0.1);
  border: 2px solid #66ff66;
  border-radius: 12px;
  padding: 16px 24px;
  color: #66ff66;
  font-size: 16px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 0 15px rgba(102, 255, 102, 0.4), inset 0 0 15px rgba(102, 255, 102, 0.1);
  font-family: 'Courier New', monospace;
  text-shadow: 0 0 10px #66ff66;
}

.activate-btn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 0 25px rgba(102, 255, 102, 0.6), inset 0 0 20px rgba(102, 255, 102, 0.2);
  background: rgba(102, 255, 102, 0.2);
}

.activate-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Result Modal - Bảng thông báo kết quả */
.result-modal-content {
  max-width: 500px;
  text-align: center;
  padding: 40px 30px;
  background: rgba(0, 0, 0, 0.95);
  backdrop-filter: blur(20px);
  border: 2px solid rgba(102, 255, 102, 0.4);
  box-shadow: 0 0 30px rgba(102, 255, 102, 0.4);
}

.result-modal-icon {
  width: 100px;
  height: 100px;
  margin: 0 auto 25px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 50px;
  animation: scaleIn 0.5s ease-out;
  position: relative;
}

.result-modal-icon::before {
  content: "";
  position: absolute;
  width: 100%;
  height: 100%;
  border-radius: 50%;
  opacity: 0.3;
  animation: pulse 2s ease-in-out infinite;
}

.result-modal-icon.success {
  background: rgba(102, 255, 102, 0.2);
  color: #66ff66;
  border: 3px solid #66ff66;
  box-shadow: 0 0 20px rgba(102, 255, 102, 0.5);
}

.result-modal-icon.error {
  background: linear-gradient(135deg, rgba(255, 68, 68, 0.2) 0%, rgba(255, 68, 68, 0.1) 100%);
  color: var(--danger);
  border: 3px solid var(--danger);
}

.result-modal-icon.warning {
  background: linear-gradient(135deg, rgba(255, 0, 0, 0.2) 0%, rgba(255, 0, 0, 0.1) 100%) !important;
  color: #ff0000 !important;
  border: 3px solid #ff0000 !important;
  animation: warningBlink 1.5s ease-in-out infinite;
}

.result-modal-icon.warning * {
  color: #ff0000 !important;
}

@keyframes warningBlink {
  0%, 100% {
    color: #ff0000 !important;
    border-color: #ff0000 !important;
    box-shadow: 0 0 20px rgba(255, 0, 0, 0.5), 0 0 40px rgba(255, 0, 0, 0.3) !important;
    background: linear-gradient(135deg, rgba(255, 0, 0, 0.2) 0%, rgba(255, 0, 0, 0.1) 100%) !important;
  }
  50% {
    color: #ff0000 !important;
    border-color: #ff0000 !important;
    box-shadow: 0 0 30px rgba(255, 0, 0, 0.8), 0 0 60px rgba(255, 0, 0, 0.5) !important;
    background: linear-gradient(135deg, rgba(255, 0, 0, 0.3) 0%, rgba(255, 0, 0, 0.2) 100%) !important;
  }
}

.result-modal-icon i {
  position: relative;
  z-index: 1;
  animation: bounceIn 0.6s ease-out;
}

.result-modal-icon.warning i {
  color: #ff0000 !important;
  animation: bounceIn 0.6s ease-out, warningIconBlink 1.5s ease-in-out infinite 0.6s;
}

@keyframes warningIconBlink {
  0%, 100% {
    color: #ff0000 !important;
    text-shadow: 0 0 10px #ff0000, 0 0 20px #ff0000, 0 0 30px #ff0000 !important;
  }
  50% {
    color: #ff0000 !important;
    text-shadow: 0 0 15px #ff0000, 0 0 30px #ff0000, 0 0 45px #ff0000 !important;
  }
}

.result-modal-title {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 15px;
  color: var(--text-primary);
  text-transform: uppercase;
  letter-spacing: 1px;
  animation: fadeInUp 0.5s ease-out 0.2s both;
}

.result-modal-message-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
  text-transform: uppercase;
  letter-spacing: 1px;
  padding-left: 0 !important;
}

.result-modal-message {
  font-size: 16px;
  line-height: 1.8;
  color: var(--text-secondary);
  margin-bottom: 30px;
  padding: 0 10px;
  animation: fadeInUp 0.5s ease-out 0.3s both;
  text-align: left;
  min-height: 200px;
}

.result-modal-message div {
  font-size: 15px;
  margin-bottom: 8px;
  padding-left: 20px;
  position: relative;
}

.result-modal-message div::before {
  content: "=>";
  position: absolute;
  left: 0;
  color: #66ff66;
  font-weight: bold;
  text-shadow: 0 0 5px #66ff66;
}

.result-modal-message .result-modal-message-title::before {
  content: none;
}

.result-modal-message .warning-step {
  color: #ff0000 !important;
}

.result-modal-message .warning-step::before {
  color: #ff0000 !important;
  text-shadow: 0 0 5px #ff0000 !important;
}

.result-modal-message.warning .warning-step {
  color: #ff0000 !important;
}

.result-modal-message .warning-step .typing-cursor {
  color: #ff0000 !important;
  text-shadow: 0 0 5px #ff0000 !important;
}

/* Cursor nhấp nháy khi đang typing */
.typing-cursor {
  display: inline-block;
  color: #66ff66;
  font-weight: bold;
  animation: blink 1s infinite;
  margin-left: 2px;
  text-shadow: 0 0 5px #66ff66;
}

@keyframes blink {
  0%, 50% {
    opacity: 1;
    text-shadow: 0 0 5px #66ff66;
  }
  51%, 100% {
    opacity: 0;
    text-shadow: none;
  }
}

.result-modal-message.success {
  color: var(--success);
}

.result-modal-message.error {
  color: var(--danger);
}

.result-modal-message.warning {
  color: #ff0000;
}

.result-close-btn {
  background: rgba(102, 255, 102, 0.1);
  border: 2px solid #66ff66;
  border-radius: 12px;
  padding: 14px 40px;
  color: #66ff66;
  font-size: 15px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 0 15px rgba(102, 255, 102, 0.4), inset 0 0 15px rgba(102, 255, 102, 0.1);
  animation: fadeInUp 0.5s ease-out 0.4s both;
  font-family: 'Courier New', monospace;
  text-shadow: 0 0 10px #66ff66;
}

.result-close-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 25px rgba(102, 255, 102, 0.6), inset 0 0 20px rgba(102, 255, 102, 0.2);
  background: rgba(102, 255, 102, 0.2);
}

.result-close-btn:active {
  transform: translateY(0);
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes shimmer {
  0% {
    transform: translateX(-100%);
  }
  100% {
    transform: translateX(100%);
  }
}

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

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

@keyframes scaleIn {
  from {
    transform: scale(0);
    opacity: 0;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}

@keyframes bounceIn {
  0% {
    transform: scale(0);
    opacity: 0;
  }
  50% {
    transform: scale(1.2);
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

@keyframes pulse {
  0%, 100% {
    transform: scale(1);
    opacity: 0.3;
  }
  50% {
    transform: scale(1.1);
    opacity: 0.1;
  }
}

/* Responsive */
@media (max-width: 600px) {
  .header__title {
    font-size: 36px;
    letter-spacing: 2px;
  }

  .check-card {
    padding: 30px 20px;
    border-radius: 16px;
  }

  .form-input::placeholder {
    font-size: 11px;
  }

  .submit-btn {
    padding: 16px 20px;
    font-size: 14px;
  }

  .modal-content {
    padding: 25px 20px;
  }

  .result-modal-content {
    padding: 30px 20px;
  }
}