/* ============================================
   Welcome / Loading Screen
   ============================================ */

.welcome-screen {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.welcome-screen.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.welcome-content {
    max-width: 560px;
    width: 90%;
    background: var(--color-surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 40px;
    position: relative;
}

.welcome-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 200px;
}

.welcome-loading.hidden {
    display: none;
}

.loading-spinner {
    width: 48px;
    height: 48px;
    border: 3px solid rgba(37, 99, 235, 0.2);
    border-top-color: var(--color-accent);
    border-radius: 50%;
    animation: spin 1s cubic-bezier(0.55, 0.055, 0.675, 0.19) infinite;
    margin-bottom: 16px;
}

.loading-text {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    color: var(--color-text-muted);
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.welcome-ready {
    text-align: center;
}

.welcome-ready.hidden {
    display: none;
}

.welcome-ready h2 {
    font-family: var(--font-serif);
    font-size: 2rem;
    font-weight: 400;
    margin: 0 0 28px;
    color: var(--color-text);
}

.welcome-description {
    font-family: var(--font-mono);
    font-size: 1rem;
    line-height: 1.5;
    color: var(--color-text);
    margin: 0 0 20px;
}

.welcome-description .methods-link {
    color: var(--color-accent);
    text-decoration: none;
    transition: opacity 0.2s;
}

.welcome-description .methods-link:hover {
    opacity: 0.7;
}

.welcome-note {
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.4;
    color: var(--color-text-muted);
    font-style: italic;
    margin: 0 0 24px;
}

.welcome-attribution {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--color-text-muted);
    margin: 20px 0 0;
    text-align: center;
}

.welcome-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    min-height: 48px;
    /* Stable height to prevent layout shift */
}

.welcome-buttons.hidden {
    display: none;
}

.buttons-loading {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    min-height: 48px;
    /* Matches button height to prevent layout shift */
}

.buttons-loading.hidden {
    display: none;
}

.small-spinner {
    width: 20px;
    height: 20px;
    border: 2px solid rgba(37, 99, 235, 0.2);
    border-top-color: var(--color-accent);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.loading-message {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--color-text-muted);
}

.btn-primary,
.btn-secondary {
    padding: 14px 36px;
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.95rem;
    font-weight: 500;
    line-height: 1;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
}

.btn-primary {
    background: #0f3b5f;
    color: white;
    animation: welcome-guide-pulse 2.4s ease-out infinite;
}

.btn-primary:hover {
    background: #0b2f4a;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(15, 59, 95, 0.4);
}

@keyframes welcome-guide-pulse {
    0% {
        box-shadow: 0 0 0 0 rgba(15, 59, 95, 0.45);
        transform: translateY(0);
    }
    70% {
        box-shadow: 0 0 0 14px rgba(15, 59, 95, 0);
        transform: translateY(-1px);
    }
    100% {
        box-shadow: 0 0 0 0 rgba(15, 59, 95, 0);
        transform: translateY(0);
    }
}

.btn-secondary {
    background: #1d4d2b;
    color: white;
    border: none;
}

.btn-secondary:hover {
    background: #173e22;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(29, 77, 43, 0.4);
}