* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: #edf1f3;
  color: #2b2b2b;
}

body {
  min-width: 320px;
}

a {
  text-decoration: none;
}

.container {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 18px;
}

/* TOP BAR */
.topbar {
  background: #24384d;
  min-height: 44px;
  display: flex;
  align-items: center;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.topbar-download-inner {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  padding: 0 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.topbar-left,
.topbar-right {
  display: flex;
  align-items: center;
  gap: 14px;
  min-height: 44px;
}

.topbar-brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #ffffff;
  margin-right: 8px;
}

.topbar-logo {
  width: 24px;
  height: 24px;
  border-radius: 6px;
  background: #21c7b6;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: #ffffff;
  font-size: 16px;
  font-weight: 700;
  line-height: 1;
  text-transform: lowercase;
}

.topbar-brand-text {
  font-size: 15px;
  font-weight: 700;
  line-height: 1;
  color: #ffffff;
}

.topbar-brand-text span {
  font-weight: 400;
}

.topbar-link {
  color: rgba(255, 255, 255, 0.95);
  font-size: 13px;
  font-weight: 600;
  line-height: 1;
}

.topbar-link:hover,
.topbar-brand:hover {
  opacity: 0.92;
}

/* HERO */
.hero {
  text-align: center;
  padding: 64px 0 42px;
}

.hero-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hero-logo {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 26px;
}

.hero-logo-icon {
  width: 84px;
  height: 84px;
  border-radius: 18px;
  background: #21c7b6;
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 50px;
  font-weight: 700;
  line-height: 1;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
}

.hero-logo-text {
  text-align: left;
}

.hero-title {
  font-size: 42px;
  font-weight: 700;
  color: #25374c;
  line-height: 1.05;
  margin: 0;
}

.hero-title span {
  font-size: 28px;
  font-weight: 600;
  color: #5a6877;
}

.hero-subtitle {
  margin-top: 8px;
  font-size: 22px;
  font-weight: 700;
  color: #33485d;
  line-height: 1.3;
}

.hero-desc {
  margin-top: 6px;
  font-size: 16px;
  color: #8c98a5;
  line-height: 1.4;
}

/* DOWNLOAD FORM */
.download-form {
  width: 100%;
  max-width: 980px;
  margin: 12px auto 8px;
  display: flex;
  align-items: stretch;
  justify-content: center;
}

.download-form input {
  flex: 1;
  min-width: 0;
  height: 72px;
  border: 1px solid #d5dde5;
  border-right: none;
  border-radius: 6px 0 0 6px;
  background: #ffffff;
  padding: 0 22px;
  font-size: 20px;
  color: #33485d;
  outline: none;
}

.download-form input::placeholder {
  color: #9aa6b2;
  font-size: 19px;
}

.download-form button {
  height: 72px;
  border: none;
  background: #24384d;
  color: #ffffff;
  padding: 0 34px;
  font-size: 20px;
  font-weight: 700;
  cursor: pointer;
  border-radius: 0 6px 6px 0;
  transition: background 0.2s ease, opacity 0.2s ease;
}

.download-form button:hover {
  background: #1d2f40;
}

.download-form button:disabled {
  opacity: 0.8;
  cursor: not-allowed;
}

.form-status {
  min-height: 22px;
  margin: 0 0 14px;
  font-size: 14px;
  color: #64748b;
  font-weight: 600;
}

.howto-btn {
  display: inline-block;
  background: #42a8ee;
  color: #ffffff;
  padding: 13px 24px;
  border-radius: 5px;
  font-size: 17px;
  font-weight: 700;
  margin-top: 2px;
  transition: background 0.2s ease;
}

.howto-btn:hover {
  background: #309ae6;
}

/* CONTENT */
.content-section {
  padding: 26px 0 34px;
}

.two-col {
  width: 100%;
  max-width: 1180px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 34px;
  align-items: start;
}

.panel {
  width: 100%;
}

.panel-header {
  padding: 13px 16px;
  color: #ffffff;
  font-size: 20px;
  font-weight: 700;
  border-radius: 4px 4px 0 0;
  line-height: 1.2;
}

.panel-header.dark {
  background: #24384d;
}

.panel-header.light {
  background: #42a8ee;
}

.update-box {
  margin-top: 10px;
  padding: 20px 18px;
  color: #ffffff;
  font-size: 18px;
  line-height: 1.6;
  border-radius: 4px;
  font-weight: 600;
}

.update-box.blue {
  background: #4ba8f0;
}

.update-box.green {
  background: #20c8a5;
}

.update-box.teal {
  background: #1cb8ae;
}

/* FAQ */
.faq-list {
  background: #ffffff;
  border: 1px solid #d6dde4;
  border-top: none;
}

.faq-item {
  border-top: 1px solid #dce3e8;
}

.faq-item:first-child {
  border-top: none;
}

.faq-question {
  width: 100%;
  border: none;
  background: #ffffff;
  padding: 17px 16px;
  text-align: left;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 14px;
  font-size: 18px;
  font-weight: 700;
  color: #36485b;
}

.faq-question span {
  color: #7b8794;
  font-size: 16px;
  flex-shrink: 0;
}

.faq-answer {
  display: none;
  padding: 0 16px 18px;
  font-size: 17px;
  line-height: 1.7;
  color: #5b6774;
  background: #ffffff;
}

.faq-item.active .faq-answer {
  display: block;
}

/* FOOTER */
.footer-box {
  padding: 58px 0 70px;
}

.footer-content {
  max-width: 900px;
  margin: 0 auto;
  background: #e5eaee;
  border: 1px solid #d8dfe6;
  padding: 28px 26px;
  text-align: center;
  border-radius: 4px;
}

.footer-content h2 {
  margin: 0 0 14px;
  font-size: 28px;
  color: #37495c;
  line-height: 1.3;
}

.footer-content p {
  margin: 10px 0;
  font-size: 17px;
  line-height: 1.7;
  color: #596777;
}

.footer-content a {
  color: #2f9be7;
  font-weight: 700;
}

/* RESPONSIVE */
@media (max-width: 1100px) {
  .hero-title {
    font-size: 36px;
  }

  .hero-title span {
    font-size: 24px;
  }

  .hero-subtitle {
    font-size: 20px;
  }

  .download-form {
    max-width: 860px;
  }

  .download-form input,
  .download-form button {
    height: 66px;
    font-size: 18px;
  }

  .download-form input::placeholder {
    font-size: 18px;
  }

  .two-col {
    max-width: 980px;
    gap: 24px;
  }
}

@media (max-width: 820px) {
  .topbar {
    padding: 8px 0;
  }

  .topbar-download-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .topbar-left,
  .topbar-right {
    flex-wrap: wrap;
    gap: 10px;
    min-height: auto;
  }

  .hero {
    padding: 48px 0 30px;
  }

  .hero-logo {
    flex-direction: column;
    text-align: center;
  }

  .hero-logo-text {
    text-align: center;
  }

  .hero-title {
    font-size: 32px;
  }

  .hero-title span {
    font-size: 22px;
  }

  .hero-subtitle {
    font-size: 19px;
  }

  .hero-desc {
    font-size: 15px;
  }

  .download-form {
    max-width: 100%;
  }

  .download-form input,
  .download-form button {
    height: 62px;
  }

  .two-col {
    grid-template-columns: 1fr;
    max-width: 760px;
  }

  .footer-content h2 {
    font-size: 24px;
  }

  .footer-content p {
    font-size: 16px;
  }
}
@media (max-width: 560px) {
  .container {
    padding: 0 14px;
  }

  .topbar-download-inner {
    padding: 0 14px;
  }

  .topbar-brand-text {
    font-size: 14px;
  }

  .topbar-link {
    font-size: 12px;
  }

  .hero {
    padding: 40px 0 24px;
  }

  .hero-logo-icon {
    width: 74px;
    height: 74px;
    font-size: 44px;
  }

  .hero-title {
    font-size: 28px;
  }

  .hero-title span {
    font-size: 20px;
  }

  .hero-subtitle {
    font-size: 17px;
  }

  .download-form {
    flex-direction: column;
    gap: 8px;
    width: 100%;
    max-width: 100%;
  }

  .download-form input,
  #urlInput {
    width: 100%;
    border: 1px solid #d5dde5;
    border-radius: 10px;
    height: 62px;
    min-height: 62px;
    padding: 0 18px;
    font-size: 18px;
    box-sizing: border-box;
  }

  .download-form input::placeholder {
    font-size: 17px;
  }

  .download-form button,
#downloadBtn {
    width: 33%;
    min-width: 140px;
    max-width: 180px;
    height: 42px;
    min-height: 42px;
    padding: 0 16px;
    font-size: 16px;
    line-height: 42px;
    font-weight: 700;
    border-radius: 10px;
    box-sizing: border-box;
    margin: 0 auto;
    display: block;
}

  .form-status {
    font-size: 13px;
    min-height: 20px;
  }

  .howto-btn {
    font-size: 15px;
    padding: 11px 18px;
  }

  .panel-header {
    font-size: 18px;
  }

  .update-box {
    font-size: 16px;
  }

  .faq-question {
    font-size: 16px;
  }

  .faq-answer {
    font-size: 15px;
  }

  .footer-content {
    padding: 22px 16px;
  }

  .footer-content h2 {
    font-size: 22px;
  }

  .footer-content p {
    font-size: 15px;
  }
}

#status {
  margin-top: 14px;
  min-height: 24px;
  font-size: 15px;
  line-height: 1.5;
  text-align: center;
}

/* ===== DOWNLOAD BUTTON UX NOTE =====
1. Hiển thị loading khi bấm Download
2. Hiển thị lỗi đẹp hơn
3. Chặn bấm liên tục nhiều lần
4. Dùng cùng với script.js
==================================== */
.status-message.info {
  color: #1f2937;
}

.status-message.loading {
  color: #2563eb;
  font-weight: 600;
}

.status-message.warning {
  color: #b45309;
  font-weight: 600;
}

.status-message.error {
  color: #dc2626;
  font-weight: 600;
}

#downloadBtn.is-loading {
  opacity: 0.85;
  cursor: not-allowed;
}