:root {
    --bg: #0f1115;
    --panel: #171a21;
    --muted: #a9b1bd;
    --text: #e6e6e6;
    --accent: #7c9cff;
    --accent-2: #71e1c2;
    --danger: #ff6b6b;
    --warn: #f8c555;
    --ok: #8be38b;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.45);
    --radius: 18px;
}
* {
    box-sizing: border-box;
}
html,
body {
    height: 100%;
}
body {
    margin: 0;
    font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto,
        Ubuntu, Cantarell, Noto Sans, Helvetica Neue, Arial, "Apple Color Emoji",
        "Segoe UI Emoji";
    color: var(--text);
    /* fond principal + couleur de secours */
    background-color: var(--bg);
    background-image: radial-gradient(
        1200px 600px at 80% -10%,
        #1a2030 0%,
        var(--bg) 60%
    );
    background-repeat: no-repeat; /* empêche la répétition */
    background-attachment: fixed; /* fond “collé” au viewport (facultatif) */
    background-size: cover; /* couvre toute la fenêtre */
}
header {
    display: flex;
    gap: 12px;
    align-items: center;
    justify-content: space-between;
    padding: 14px 18px;
    position: sticky;
    top: 0;
    z-index: 30;
    background: linear-gradient(
        180deg,
        rgba(23, 26, 33, 0.95),
        rgba(23, 26, 33, 0.65) 70%,
        rgba(23, 26, 33, 0)
    );
    backdrop-filter: blur(6px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}
.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    letter-spacing: 0.2px;
}
.brand .logo {
    width: 28px;
    height: 28px;
    object-fit: contain;
}
.muted {
    color: var(--muted);
    font-size: 0.9rem;
}

.wrap {
    max-width: 980px;
    margin: 0 auto;
    padding: 22px;
}

.panel {
    background: linear-gradient(
        180deg,
        rgba(255, 255, 255, 0.04),
        rgba(255, 255, 255, 0.02)
    );
    border: 1px solid rgba(255, 255, 255, 0.06);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.controls {
    display: grid;
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 16px;
}
@media (min-width: 760px) {
    .controls {
        grid-template-columns: 1.4fr 1fr 1fr;
    }
}
@media (max-width: 480px) {
    .controls {
        grid-template-columns: 1fr;
    }
}

.control-block {
    padding: 12px;
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.03);
    border: 1px dashed rgba(255, 255, 255, 0.08);
}
.control-block h3 {
    margin: 0 0 8px;
    font-size: 1rem;
    font-weight: 700;
}

.btn {
    cursor: pointer;
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.06);
    color: var(--text);
    padding: 10px 14px;
    border-radius: 12px;
    font-weight: 600;
    transition: 0.15s ease;
}
.btn:hover {
    transform: translateY(-1px);
    background: rgba(255, 255, 255, 0.1);
}
.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}
.btn-light {
    background: transparent;
}

.file-zone {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}
@media (max-width: 480px) {
    .file-zone {
        flex-direction: column;
        align-items: stretch;
    }
    .file-name {
        width: 100%;
    }
}
#csvFile {
    display: none;
}
.file-label {
    padding: 10px 14px;
    border-radius: 12px;
    border: 1px dashed rgba(255, 255, 255, 0.18);
    cursor: pointer;
}
.file-name {
    font-size: 0.9rem;
    color: var(--muted);
    max-width: 320px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.flex {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}
.grow {
    flex: 1;
}
.right {
    margin-left: auto;
}

.card-space {
    margin-top: 18px;
    padding: 18px;
}

.card {
    user-select: none;
    margin: 0 auto;
    max-width: 720px;
    min-height: clamp(200px, 35vh, 360px);
    border-radius: 22px;
    padding: 28px;
    text-align: center;
    display: grid;
    align-items: center;
    justify-content: center;
    background: radial-gradient(
        800px 400px at 50% -10%,
        #21283a 0%,
        var(--panel) 55%
    );
    border: 1px solid rgba(255, 255, 255, 0.08);
    box-shadow: 0 12px 50px rgba(0, 0, 0, 0.35);
    position: relative;
}
.card .side {
    font-size: clamp(18px, 4.2vw, 38px);
    line-height: 1.25;
    letter-spacing: 0.2px;
}
.card .back {
    display: none;
}
.card.flipped .front {
    display: none;
}
.card.flipped .back {
    display: block;
}

.card .hint {
    position: absolute;
    bottom: 12px;
    left: 0;
    right: 0;
    color: var(--muted);
    font-size: 0.9rem;
}

.actions {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    margin-top: 14px;
}
@media (max-width: 560px) {
    .actions {
        grid-template-columns: repeat(2, 1fr);
    }
}
.actions .btn {
    padding: 12px;
    font-weight: 800;
}
.again {
    border-color: rgba(255, 0, 0, 0.35);
    background: rgba(255, 0, 0, 0.09);
}
.hard {
    border-color: rgba(255, 165, 0, 0.35);
    background: rgba(255, 165, 0, 0.08);
}
.good {
    border-color: rgba(100, 200, 120, 0.35);
    background: rgba(100, 200, 120, 0.08);
}
.easy {
    border-color: rgba(120, 160, 255, 0.35);
    background: rgba(120, 160, 255, 0.09);
}

.status {
    display: flex;
    gap: 14px;
    align-items: center;
    flex-wrap: wrap;
    margin-top: 16px;
    color: var(--muted);
    font-size: 0.95rem;
}
@media (max-width: 560px) {
    .status {
        font-size: 0.85rem;
    }
}
.pill {
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.1);
    padding: 6px 10px;
    border-radius: 999px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
}

.hidden {
    display: none;
}

.footer {
    margin-top: 24px;
    padding: 14px;
    color: var(--muted);
    text-align: center;
    font-size: 0.9rem;
}

.kbd {
    font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas,
        "Liberation Mono", "Courier New", monospace;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-bottom-width: 2px;
    padding: 2px 6px;
    border-radius: 6px;
}

.progress {
    height: 8px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.07);
    overflow: hidden;
}
.progress > div {
    height: 100%;
    width: 0%;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    transition: width 0.3s ease;
}

details {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid rgba(255, 255, 255, 0.08);
    padding: 10px 12px;
    border-radius: 10px;
}
details summary {
    cursor: pointer;
    font-weight: 700;
}

/* Search panel */
.search-panel {
    margin-top: 18px;
    padding: 16px;
}
.search-input::placeholder {
    color: rgba(255, 255, 255, 0.6);
}
.search-row {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 10px;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px dashed rgba(255, 255, 255, 0.06);
}
@media (max-width: 560px) {
    .search-row {
        grid-template-columns: 1fr;
    }
    .search-row .btn {
        width: 100%;
    }
}
.search-row:last-child {
    border-bottom: none;
}
.search-meta {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    font-size: 0.9rem;
    color: var(--muted);
}
.search-input {
    width: 100%;
    padding: 10px 12px;
    border-radius: 10px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.05);
    color: var(--text);
}
.tag {
    padding: 2px 6px;
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.05);
    font-size: 0.8rem;
}

/* SRS params styling */
details[open] {
    background: rgba(255, 255, 255, 0.06);
    border-color: rgba(255, 255, 255, 0.15);
}
.srs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 12px;
    margin-top: 12px;
}
.srs-param {
    display: flex;
    flex-direction: column;
    gap: 4px;
}
.srs-param label {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text);
}
.srs-param input {
    padding: 8px 10px;
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.05);
    color: var(--text);
    font-size: 0.9rem;
    width: 100%;
}
.srs-param input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px rgba(124, 156, 255, 0.2);
}
.srs-param small {
    color: var(--muted);
    font-size: 0.8rem;
    line-height: 1.3;
}