:root {
    --primary: #ff4757;
    --primary-dark: #ff3838;
    --primary-soft: #ff6b7a;
    --bg-dark: #0f1419;
    --bg-card: #1a1f2e;
    --bg-alt: #252d3d;
    --line: #2f455f;
    --text-main: #ffffff;
    --text-muted: #b8c5d6;
    --ok: #74dfa7;
    --warn: #ffd27f;
    --danger: #ff9797;
}

* {
    box-sizing: border-box;
}

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

body {
    font-family: 'Trebuchet MS', 'Gill Sans', 'Segoe UI', sans-serif;
    color: var(--text-main);
    background:
        radial-gradient(circle at 14% 10%, rgba(255, 71, 87, 0.24), transparent 34%),
        radial-gradient(circle at 90% 6%, rgba(255, 107, 122, 0.14), transparent 28%),
        linear-gradient(130deg, var(--bg-dark), #151c27 58%, #101620);
    background-attachment: fixed;
    padding: 24px 16px 44px;
}

.solo-wrap {
    width: min(980px, 100%);
    margin: 0 auto;
    display: grid;
    gap: 14px;
}

.top-bar {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 12px;
}

.eyebrow {
    margin: 0;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-size: 0.76rem;
    color: var(--primary-soft);
}

h1 {
    margin: 5px 0 8px;
    font-size: clamp(1.75rem, 2.1vw + 1rem, 2.7rem);
}

.subtitle {
    margin: 0;
    color: var(--text-muted);
}

.header-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.home-link {
    text-decoration: none;
    color: var(--text-main);
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 9px 12px;
    background: rgba(255, 255, 255, 0.04);
    font-weight: 700;
}

.home-link:hover {
    border-color: var(--primary-soft);
}

.card {
    background: linear-gradient(150deg, var(--bg-card), var(--bg-alt));
    border: 1px solid var(--line);
    border-radius: 16px;
    padding: 18px;
    box-shadow: 0 18px 44px rgba(0, 0, 0, 0.36);
}

h2 {
    margin: 0 0 10px;
}

.settings-grid {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: 10px;
}

.theme-picker {
    margin-top: 14px;
    padding-top: 12px;
    border-top: 1px dashed rgba(255, 255, 255, 0.16);
}

.theme-picker-label {
    margin: 0;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.76rem;
}

.theme-pills {
    margin-top: 8px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.theme-pill {
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-main);
    padding: 7px 11px;
    cursor: pointer;
    font-weight: 700;
    font-size: 0.82rem;
}

.theme-pill.is-active {
    border-color: var(--primary-soft);
    background: rgba(255, 107, 122, 0.22);
}

label {
    display: grid;
    gap: 6px;
    color: var(--text-muted);
    font-size: 0.9rem;
}

input[type='number'],
input[type='text'] {
    border: 1px solid var(--line);
    border-radius: 10px;
    background: rgba(0, 0, 0, 0.22);
    color: var(--text-main);
    padding: 10px 11px;
}

.settings-actions,
.answer-actions {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 12px;
}

.btn {
    border: none;
    border-radius: 10px;
    padding: 10px 13px;
    font-weight: 800;
    cursor: pointer;
}

.btn.primary {
    color: #fff;
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
}

.btn.subtle {
    color: var(--text-main);
    background: rgba(255, 255, 255, 0.12);
    border: 1px solid var(--line);
}

.btn:hover {
    filter: brightness(1.07);
}

.stats-row {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 8px;
}

.stats-row p {
    margin: 0;
    color: var(--text-muted);
}

.stats-row strong {
    color: var(--text-main);
}

.timer-bar {
    margin: 12px 0 10px;
    width: 100%;
    height: 12px;
    border-radius: 999px;
    border: 1px solid var(--line);
    overflow: hidden;
    background: rgba(255, 255, 255, 0.08);
}

.timer-bar span {
    display: block;
    width: 0;
    height: 100%;
    background: linear-gradient(90deg, #69dda9 0%, #ffd685 60%, #ff8f8f 100%);
    transition: width 0.22s linear;
}

.label {
    margin: 0;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.74rem;
    color: var(--text-muted);
}

.prompt-value,
.solution-value {
    margin: 8px 0 0;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: rgba(0, 0, 0, 0.2);
    padding: 14px;
    font-size: clamp(1.1rem, 1.2vw + 0.8rem, 1.5rem);
    min-height: 64px;
}

.answer-zone {
    margin-top: 14px;
}

.solution-box {
    margin-top: 10px;
}

.rating-row {
    margin-top: 12px;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 8px;
}

.rating-btn {
    border: none;
    border-radius: 10px;
    padding: 10px;
    font-weight: 800;
    cursor: pointer;
}

.rating-btn.again {
    background: #ff5f6a;
    color: #ffffff;
}

.rating-btn.hard {
    background: #ff8c42;
    color: #1b232d;
}

.rating-btn.good {
    background: #62d39e;
    color: #12212d;
}

.rating-btn.easy {
    background: #7ec3ff;
    color: #0f2434;
}

.rating-btn:hover {
    filter: brightness(1.08);
}

.feedback {
    margin: 10px 0 0;
    min-height: 1.3em;
}

.feedback.muted {
    color: var(--text-muted);
}

.feedback.success {
    color: var(--ok);
}

.feedback.warning {
    color: var(--warn);
}

.feedback.error {
    color: var(--danger);
}

.hidden {
    display: none !important;
}

@media (max-width: 980px) {
    .settings-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 680px) {
    body {
        padding: 18px 12px 28px;
    }

    .top-bar {
        flex-direction: column;
        align-items: flex-start;
    }

    .stats-row {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .rating-row {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}