/* iOS-Inspired Liquid / Glass Buttons */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    font-size: 0.95rem;
    font-weight: 600;
    line-height: 1.2;
    border-radius: var(--radius-full);
    border: 1px solid transparent;
    transition: transform var(--transition-micro), background-color var(--transition-micro), box-shadow var(--transition-micro), opacity var(--transition-micro);
    user-select: none;
    white-space: nowrap;
}

.btn:active:not(:disabled) {
    transform: scale(0.975);
}

.btn:disabled {
    opacity: 0.55;
    cursor: not-allowed;
    transform: none;
}

/* Primary Glass Gradient Button */
.btn-primary {
    background-image: var(--brand-gradient);
    color: #ffffff;
    border: 1px solid rgba(255, 255, 255, 0.25);
    box-shadow: 0 4px 16px var(--brand-glow), inset 0 1px 1px rgba(255, 255, 255, 0.35);
}

.btn-primary:hover:not(:disabled) {
    box-shadow: 0 6px 22px var(--brand-glow), inset 0 1px 1px rgba(255, 255, 255, 0.5);
    filter: brightness(1.05);
}

/* Secondary Frosted Glass Button */
.btn-glass {
    background-color: var(--surface-glass);
    color: var(--text-primary);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--surface-border-glass);
    box-shadow: var(--shadow-sm), inset 0 1px 1px rgba(255, 255, 255, 0.4);
}

.btn-glass:hover:not(:disabled) {
    background-color: var(--surface-elevated);
    box-shadow: var(--shadow-md);
}

/* Compact Button */
.btn-sm {
    padding: 6px 14px;
    font-size: 0.85rem;
    border-radius: var(--radius-md);
}

/* Large CTA Button */
.btn-lg {
    padding: 14px 28px;
    font-size: 1.05rem;
    border-radius: var(--radius-full);
}

/* Small Floating Theme Switcher Button (Right Bottom Corner) */
.btn-theme-floating {
    position: fixed;
    right: 18px;
    bottom: 82px; /* Sits cleanly above 64px mobile bottom nav */
    z-index: 1050;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-full);
    background: var(--surface-glass);
    border: 1.5px solid var(--surface-border);
    color: var(--text-primary);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 6px 22px rgba(0, 0, 0, 0.16);
    transition: transform var(--transition-micro), background var(--transition-micro), box-shadow var(--transition-micro);
}

.btn-theme-floating:hover {
    transform: scale(1.08);
    background: var(--surface-elevated);
    box-shadow: 0 8px 26px rgba(0, 0, 0, 0.22);
}

.btn-theme-floating:active {
    transform: scale(0.92);
}

.btn-theme-floating i,
.btn-theme-floating svg {
    width: 20px;
    height: 20px;
    color: var(--brand-primary);
    transition: transform 0.3s ease;
}

[data-theme="dark"] .btn-theme-floating {
    box-shadow: 0 6px 26px rgba(0, 0, 0, 0.45);
    background: rgba(18, 24, 38, 0.9);
    border-color: rgba(255, 255, 255, 0.14);
}

[data-theme="dark"] .btn-theme-floating i,
[data-theme="dark"] .btn-theme-floating svg {
    color: #facc15; /* Golden sun in dark mode */
}

@media (min-width: 769px) {
    .btn-theme-floating {
        bottom: 24px;
        right: 24px;
        width: 48px;
        height: 48px;
    }
}