:root {
  --color-bg: #0f1720;
  --color-bg-soft: #16212c;
  --color-surface: #1c2a37;
  --color-border: #2a3a48;
  --color-text: #eef3f7;
  --color-text-muted: #9fb0bd;
  --color-primary: #2fb8a6;
  --color-primary-hover: #26a394;
  --color-accent: #4f8ef7;
  --color-error: #ef6a6a;
  --color-success: #3fcf8e;
  --radius: 14px;
  --shadow: 0 12px 30px rgba(0, 0, 0, 0.35);
  --max-width: 640px;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
}

body {
  min-height: 100vh;
  background:
    radial-gradient(1200px 600px at 50% -10%, rgba(79, 142, 247, 0.18), transparent),
    radial-gradient(900px 500px at 90% 10%, rgba(47, 184, 166, 0.14), transparent),
    var(--color-bg);
  color: var(--color-text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5;
  display: flex;
  flex-direction: column;
}

/* -------------------- Header -------------------- */

.site-header {
  padding: 20px 24px;
  display: flex;
  justify-content: center;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
}

.brand-mark {
  font-size: 1.4rem;
}

.brand-name {
  color: var(--color-text);
}

/* -------------------- Main / Hero -------------------- */

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 24px 20px 60px;
}

.hero {
  width: 100%;
  max-width: var(--max-width);
  text-align: center;
  margin-top: 28px;
  margin-bottom: 40px;
}

.hero h1 {
  font-size: clamp(2.4rem, 6vw, 3.4rem);
  margin: 0 0 12px;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(90deg, var(--color-accent), var(--color-primary));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.subtitle {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--color-text);
  margin: 0 0 10px;
}

.description {
  font-size: 1rem;
  color: var(--color-text-muted);
  margin: 0 auto;
  max-width: 480px;
}

/* -------------------- Tester zone -------------------- */

.tester-zone {
  width: 100%;
  max-width: var(--max-width);
  display: flex;
  justify-content: center;
}

.card {
  width: 100%;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px 24px;
  text-align: center;
}

.card h2 {
  margin: 0 0 18px;
  font-size: 1.25rem;
  font-weight: 700;
}

.access-form {
  display: flex;
  flex-direction: column;
  gap: 12px;
  align-items: stretch;
}

.access-form label {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  text-align: left;
}

.access-form input {
  background: var(--color-bg-soft);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  padding: 12px 14px;
  color: var(--color-text);
  font-size: 1rem;
  outline: none;
  transition: border-color 0.15s ease;
}

.access-form input:focus {
  border-color: var(--color-accent);
}

.access-form input::placeholder {
  color: var(--color-text-muted);
}

.btn {
  border: none;
  border-radius: 10px;
  padding: 13px 20px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.1s ease, background-color 0.15s ease, opacity 0.15s ease;
}

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

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

.btn-primary {
  background: var(--color-primary);
  color: #06201c;
}

.btn-primary:hover {
  background: var(--color-primary-hover);
}

.btn-download {
  background: var(--color-accent);
  color: #08172f;
  width: 100%;
}

.btn-download:hover {
  opacity: 0.9;
}

.error-message {
  color: var(--color-error);
  font-size: 0.9rem;
  margin: 2px 0 0;
  text-align: left;
}

.access-granted {
  display: flex;
  flex-direction: column;
  gap: 14px;
  align-items: stretch;
}

.access-granted[hidden] {
  display: none;
}

.success-message {
  color: var(--color-success);
  font-weight: 700;
  font-size: 1.05rem;
  margin: 0;
}

.download-note {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin: 0;
}

/* -------------------- Footer -------------------- */

.site-footer {
  padding: 18px 20px 28px;
  text-align: center;
}

.site-footer p {
  margin: 0;
  font-size: 0.78rem;
  color: var(--color-text-muted);
  max-width: 520px;
  margin: 0 auto;
}

/* -------------------- Responsive -------------------- */

@media (min-width: 640px) {
  .site-header {
    padding: 28px 32px;
  }

  .card {
    padding: 36px 40px;
  }
}

@media (max-width: 380px) {
  .hero h1 {
    font-size: 2.1rem;
  }

  .card {
    padding: 22px 18px;
  }
}