:root {
    --accent: #2979ff;
    --accent-soft: rgba(41, 121, 255, 0.12);
    --text: #263238;
    --muted: #607d8b;
    --bg: #f7f9fc;
    --surface: #ffffff;
    --border: #d7e0ea;
    --danger: #d32f2f;
    --shadow: 0 18px 50px rgba(38, 50, 56, 0.08);
    --radius: 16px;
    --font: "Commissioner", "Segoe UI", sans-serif;
}

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

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

body {
    font-family: var(--font);
    color: var(--text);
    background:
        radial-gradient(1200px 600px at 10% -10%, rgba(41, 121, 255, 0.16), transparent 55%),
        radial-gradient(900px 500px at 100% 0%, rgba(41, 121, 255, 0.08), transparent 45%),
        linear-gradient(180deg, #ffffff 0%, var(--bg) 100%);
    -webkit-font-smoothing: antialiased;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

.progress {
    position: fixed;
    inset: 0 0 auto;
    height: 4px;
    background: rgba(38, 50, 56, 0.08);
    z-index: 20;
}

.progress__bar {
    height: 100%;
    width: 0;
    background: linear-gradient(90deg, #1e88e5, var(--accent));
    transition: width 320ms cubic-bezier(0.22, 1, 0.36, 1);
}

.shell {
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 72px 20px 48px;
}

.step {
    width: min(680px, 100%);
    background: color-mix(in srgb, var(--surface) 92%, transparent);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.7);
    border-radius: calc(var(--radius) + 4px);
    box-shadow: var(--shadow);
    padding: clamp(28px, 5vw, 48px);
    animation: rise-in 420ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.step[hidden] {
    display: none !important;
}

.step__counter {
    margin: 0 0 14px;
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.02em;
}

.step__counter span {
    opacity: 0.55;
}

.step__title {
    margin: 0;
    font-size: clamp(1.7rem, 4vw, 2.35rem);
    line-height: 1.2;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: -0.02em;
}

.step__hint {
    margin: 14px 0 0;
    color: var(--muted);
    font-size: 1.05rem;
    line-height: 1.5;
}

.field {
    display: block;
    margin-top: 28px;
}

.field input {
    width: 100%;
    border: 0;
    border-bottom: 2px solid var(--border);
    background: transparent;
    color: var(--text);
    font: inherit;
    font-size: 1.35rem;
    padding: 12px 2px;
    outline: none;
    transition: border-color 180ms ease, box-shadow 180ms ease;
}

.field input::placeholder {
    color: #90a4ae;
}

.field input:focus {
    border-color: var(--accent);
    box-shadow: 0 2px 0 var(--accent);
}

.choices {
    display: grid;
    gap: 12px;
    margin-top: 28px;
}

.choice {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 18px;
    border: 1.5px solid var(--border);
    border-radius: 14px;
    background: #fff;
    cursor: pointer;
    transition: border-color 160ms ease, background 160ms ease, transform 160ms ease;
}

.choice:hover {
    border-color: color-mix(in srgb, var(--accent) 55%, var(--border));
    transform: translateY(-1px);
}

.choice:has(input:checked) {
    border-color: var(--accent);
    background: var(--accent-soft);
}

.choice input {
    accent-color: var(--accent);
    width: 18px;
    height: 18px;
}

.choice span {
    font-size: 1.05rem;
    font-weight: 500;
}

.step__error {
    margin: 14px 0 0;
    color: var(--danger);
    font-size: 0.95rem;
}

.step__actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 32px;
}

.btn {
    appearance: none;
    border: 0;
    border-radius: 999px;
    font: inherit;
    font-weight: 600;
    font-size: 1rem;
    padding: 14px 22px;
    cursor: pointer;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: transform 160ms ease, background 160ms ease, opacity 160ms ease;
}

.btn:active {
    transform: translateY(1px);
}

.btn--primary {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 10px 24px rgba(41, 121, 255, 0.28);
}

.btn--primary:hover {
    background: #1e6cf0;
}

.btn--primary:disabled {
    opacity: 0.65;
    cursor: wait;
}

.btn--ghost {
    background: transparent;
    color: var(--muted);
    border: 1px solid var(--border);
}

.btn span {
    opacity: 0.75;
    font-size: 0.95rem;
}

.toast {
    position: fixed;
    left: 50%;
    bottom: 24px;
    transform: translateX(-50%);
    background: #263238;
    color: #fff;
    padding: 12px 18px;
    border-radius: 999px;
    font-size: 0.95rem;
    z-index: 30;
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.18);
}

.toast[hidden] {
    display: none !important;
}

@keyframes rise-in {
    from {
        opacity: 0;
        transform: translateY(18px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (prefers-reduced-motion: reduce) {
    .step,
    .progress__bar,
    .btn,
    .choice {
        animation: none !important;
        transition: none !important;
    }
}

@media (max-width: 640px) {
    .shell {
        padding: 56px 14px 32px;
        place-items: start center;
    }

    .step {
        padding: 24px 18px 28px;
        box-shadow: none;
        border: 0;
        background: transparent;
        backdrop-filter: none;
    }

    .step__title {
        font-size: 1.65rem;
    }

    .field input {
        font-size: 1.2rem;
    }
}