:root {
  color-scheme: light;
  --bg: #f3efe7;
  --panel: #fffdf9;
  --ink: #1f2933;
  --muted: #6b7280;
  --accent: #0f766e;
  --accent-hover: #115e59;
  --border: rgba(15, 118, 110, 0.16);
  --shadow: 0 24px 60px rgba(31, 41, 51, 0.12);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  font-family: "Segoe UI", Arial, sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top, rgba(15, 118, 110, 0.1), transparent 35%),
    linear-gradient(180deg, #f7f3ec 0%, var(--bg) 100%);
}

button,
input,
textarea,
select {
  font: inherit;
}

.shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.shell--compact {
  min-height: 100%;
  padding: 16px;
}

.panel {
  width: min(100%, 560px);
  padding: 40px 32px;
  border: 1px solid var(--border);
  border-radius: 24px;
  background: var(--panel);
  box-shadow: var(--shadow);
  text-align: center;
}

.panel--activity {
  width: min(100%, 480px);
}

.eyebrow {
  margin: 0 0 12px;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent);
}

h1 {
  margin: 0;
  font-size: clamp(2rem, 4vw, 2.6rem);
  line-height: 1.05;
}

.copy {
  margin: 16px auto 0;
  max-width: 42ch;
  color: var(--muted);
  line-height: 1.6;
}

.action-button {
  margin-top: 28px;
  border: 0;
  border-radius: 999px;
  padding: 14px 24px;
  min-width: 220px;
  font-weight: 700;
  color: #ffffff;
  background: var(--accent);
  cursor: pointer;
  transition: transform 0.18s ease, background-color 0.18s ease, opacity 0.18s ease;
}

.action-button:hover,
.action-button:focus-visible {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.action-button:disabled {
  opacity: 0.7;
  cursor: wait;
  transform: none;
}

.activity-overlay {
  position: fixed;
  inset: 0;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: rgba(17, 24, 39, 0.54);
}

.activity-overlay--active {
  display: flex;
}

.activity-frame-wrap {
  width: min(100%, 900px);
  height: min(100%, 640px);
  border-radius: 24px;
  overflow: hidden;
  box-shadow: var(--shadow);
  background: #ffffff;
}

#activity-frame {
  width: 100%;
  height: 100%;
  border: 0;
}

.activity-page {
  background: linear-gradient(180deg, #f9fafb 0%, #eef4f2 100%);
}

@media (max-width: 640px) {
  .panel {
    padding: 32px 20px;
    border-radius: 20px;
  }

  .activity-overlay {
    padding: 12px;
  }

  .activity-frame-wrap {
    height: min(100%, 520px);
    border-radius: 18px;
  }

  .action-button {
    width: 100%;
    min-width: 0;
  }
}