:root {
    --bg-gradient-start: #f6f9fc;
    --bg-gradient-end: #edf2fa;
    --surface-card: rgba(255, 255, 255, 0.88);
    --text-primary: #13294b;
    --text-secondary: #3e4b62;
    --text-muted: #5b6f8c;
    --accent-primary: #2563eb;
    --accent-soft: rgba(37, 99, 235, 0.1);
    --accent-gradient: linear-gradient(145deg, #2563eb, #1d4ed8);
    --border-light: rgba(100, 116, 139, 0.18);
    --shadow-elevation: 0 20px 35px -8px rgba(15, 23, 42, 0.12), 0 6px 12px -4px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 26px 40px -12px rgba(37, 99, 235, 0.22);
    --radius-main: 32px;
    --radius-card: 24px;
    --radius-element: 18px;
    --transition-standard: all 0.25s ease;
}

.card-page {
    max-width: 1240px;
    margin: 0 auto;
    position: relative;
}

.card-shell {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 28px;
    align-items: stretch;
}

.panel {
    background: var(--surface-card);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.5);
    border-radius: var(--radius-main);
    box-shadow: var(--shadow-elevation);
    transition: var(--transition-standard);
    padding: 32px;
}

.panel:hover {
    box-shadow: var(--shadow-hover);
    border-color: rgba(255, 255, 255, 0.8);
}

.panel-badge {
    display: inline-flex;
    align-items: center;
    padding: 8px 18px;
    border-radius: 40px;
    background: var(--accent-soft);
    color: var(--accent-primary);
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 0.3px;
    border: 1px solid rgba(37,99,235,0.2);
    width: fit-content;
}

.panel-title {
    margin: 18px 0 10px;
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    line-height: 1.15;
    color: var(--text-primary);
}

.panel-desc {
    margin: 0;
    color: var(--text-secondary);
    line-height: 1.8;
    font-size: 14px;
}

.action-grid {
    display: grid;
    gap: 16px;
    margin-top: 28px;
}

.action-btn,
.submit-btn {
    border: 1px solid rgba(255,255,255,0.24);
    border-radius: 22px;
    padding: 18px 20px;
    background: var(--accent-gradient);
    color: #fff;
    cursor: pointer;
    box-shadow: 0 18px 30px -8px rgba(37,99,235,0.3);
    transition: var(--transition-standard);
    text-align: left;
    width: 100%;
}

.action-btn:hover,
.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 22px 38px -8px rgba(37,99,235,0.36);
}

.action-btn:disabled,
.submit-btn:disabled,
.copy-btn:disabled {
    opacity: 0.7;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.action-title {
    display: block;
    font-size: 18px;
    font-weight: 800;
    letter-spacing: 0.2px;
}

.action-subtitle {
    display: block;
    margin-top: 6px;
    font-size: 13px;
    opacity: 0.92;
    line-height: 1.6;
}

.card-form {
    margin-top: 28px;
    display: grid;
    gap: 18px;
}

.field-group {
    display: grid;
    gap: 10px;
}

.field-group textarea {
    width: 100%;
    min-height: 140px;
    padding: 14px 16px;
    border-radius: var(--radius-element);
    border: 1px solid var(--border-light);
    background: rgba(255,255,255,0.95);
    color: var(--text-primary);
    font-size: 15px;
    line-height: 1.7;
    resize: vertical;
    box-sizing: border-box;
    transition: var(--transition-standard);
}

.field-group textarea:focus {
    outline: none;
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 4px rgba(37,99,235,0.15);
    background: #fff;
}

.helper-text {
    color: var(--text-muted);
    font-size: 13px;
    line-height: 1.6;
}

.invite-share {
    margin-top: 24px;
    padding: 20px 22px;
    border-radius: var(--radius-card);
    background: rgba(255,255,255,0.72);
    border: 1px solid rgba(255,255,255,0.9);
    box-shadow: 0 12px 24px -14px rgba(15, 23, 42, 0.22);
}

.invite-share-title {
    margin: 0 0 10px;
    font-size: 18px;
    font-weight: 800;
    color: var(--text-primary);
}

.invite-share-row {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 12px;
    align-items: center;
    margin-top: 14px;
}

.invite-link-box {
    min-height: 54px;
    padding: 14px 16px;
    border-radius: 16px;
    border: 1px solid var(--border-light);
    background: rgba(255,255,255,0.94);
    color: var(--text-primary);
    font-size: 14px;
    line-height: 1.7;
    word-break: break-all;
}

.copy-btn {
    border: 0;
    border-radius: 16px;
    padding: 14px 18px;
    background: linear-gradient(145deg, #0f766e, #0d9488);
    color: #fff;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition-standard);
    white-space: nowrap;
}

.copy-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 16px 26px -12px rgba(13, 148, 136, 0.45);
}

.result-box {
    display: none;
    margin-top: 18px;
    padding: 16px 20px;
    border-radius: 20px;
    font-size: 14px;
    line-height: 1.7;
    font-weight: 500;
    white-space: pre-line;
}

.result-box.show {
    display: block;
    animation: fadeSlide 0.3s ease;
}

.result-box.success {
    background: rgba(15, 157, 88, 0.12);
    color: #0c7b45;
    border: 1px solid rgba(15, 157, 88, 0.25);
}

.result-box.error {
    background: rgba(217, 48, 37, 0.1);
    color: #b0281a;
    border: 1px solid rgba(217, 48, 37, 0.2);
}

@keyframes fadeSlide {
    from {
        opacity: 0;
        transform: translateY(-6px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

#inviteBox {
    position: fixed;
    top: 80px;
    left: 24px;
    background: rgba(255,255,255,0.9);
    backdrop-filter: blur(16px);
    padding: 14px 22px;
    border-radius: 40px;
    border: 1px solid rgba(255,255,255,0.8);
    box-shadow: 0 12px 28px -8px rgba(0,0,0,0.15);
    font-size: 15px;
    font-weight: 600;
    color: #1e3a8a;
    cursor: move;
    z-index: 200;
    user-select: none;
    border-left: 4px solid var(--accent-primary);
}

.invite-text span {
    background: var(--accent-primary);
    color: white;
    padding: 4px 12px;
    border-radius: 40px;
    margin-left: 8px;
    font-weight: 700;
}

@media (max-width: 960px) {
    .card-shell {
        grid-template-columns: 1fr;
    }

    body {
        padding: 20px 16px 100px;
    }

    .panel {
        padding: 28px;
    }

    .invite-share-row {
        grid-template-columns: 1fr;
    }

    #inviteBox {
        top: 70px;
        left: 16px;
        padding: 10px 18px;
    }
}