/* ========== 响应式主卡片与全局 ========== */
body {
    background: linear-gradient(135deg, #22293b 0%, #16191d 100%) center top !important;
}

.container {
    max-width: 700px;
    margin: 0 auto;
}

.panel {
    background: #181d25;
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.35);
    border-radius: 1.5rem;
    padding: 1.5rem 2rem 1.5rem 2rem;
}

@media (max-width: 600px) {
    .panel {
        max-width: 99vw;
        padding: 0.8rem 1.6rem;
    }
}

.avatar-big {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    object-fit: cover;
    margin: 0.3rem 1rem 0.3rem 0;
    background: #293651;
}

@media (max-width: 600px) {
    .avatar-big {
        width: 32px;
        height: 32px;
    }
}

/* ======== 平台nav与客户端btn ======== */
.nav-platforms {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
    justify-content: center;
}

.nav-platforms .nav-link {
    flex: 1 1 auto;
    min-width: 80px;
    padding: 0.5rem 0.75rem;
    font-size: 0.95rem;
}

.nav-platforms .nav-link.active {
    color: #fff !important;
    background: linear-gradient(90deg, #19acf4 50%, #13e5ce 150%);
    font-weight: 700;
    border-radius: 9px;
}

.nav-platforms .nav-link {
    color: #2ec2e6 !important;
    border-radius: 8px;
    margin-right: 4px;
    font-weight: 500;
    background: #191e2e;
    font-size: 1rem;
    min-width: 64px;
    text-align: center;
}

.info-label {
    color: #fff;
}

.info-value {
    color: #fff;
}

#apps-tab {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 1rem;
}

#apps-tab .btn-app.selected,
#apps-tab .btn-app.btn-primary {
    background: linear-gradient(83deg, #24a4fa 20%, #23e1b7 150%) !important;
    color: #fff !important;
    border: none;
    font-weight: 600;
}

#apps-tab .btn-app {
    margin-right: 8px;
    margin-bottom: 6px;
    border: 1.1px solid #1ed6eb40;
    background: #1a283b;
    color: #65e8fc;
    min-width: 96px;
    text-align: center;
    font-weight: 500;
}

/* ======= stepper主线和icon完美对齐 ======= */
.stepper {
    margin-top: 2em;
}

@media (max-width: 600px) {
    .stepper {
        margin-top: 1em;
    }
}

.stepper {
    position: relative;
    --dot-width: 36px;
    --line-width: 4px;
}

.stepper::before {
    content: "";
    position: absolute;
    top: calc(var(--dot-width) / 2);
    bottom: calc(var(--dot-width) / 2);
    left: calc((var(--dot-width) - var(--line-width)) / 2);
    width: var(--line-width);
    background: #29dbe236;
    border-radius: 3px;
    z-index: 0;
}

.step-item {
    display: flex;
    align-items: flex-start;
    position: relative;
    margin-bottom: 2.5rem;
}

.step-dot {
    width: var(--dot-width);
    height: var(--dot-width);
    min-width: var(--dot-width);
    min-height: var(--dot-width);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    position: relative;
    z-index: 2;
    margin-right: 1.2rem;
    margin-left: 0;
    box-shadow: 0 0 8px rgba(34, 202, 236, 0.8);
    background: linear-gradient(145deg, #30b1ef 0%, #50edaf 100%);
    color: #fff;
    font-size: 1.2rem;
    font-weight: bold;
}

.step-title {
    font-weight: 600;
    margin-bottom: 0.2em;
    color: #e0f2ff;
    font-size: 1.15em;
}

.step-desc {
    color: #b1c9de;
    font-size: 0.98em;
    margin-bottom: 0.33em;
}

.btn-group .btn, .btn-round-sm,
.addsub-btn {
    border-radius: 9px !important;
}

.dropdown-menu {
    border-radius: 12px;
}

.app-download {
    display: flex;
    justify-content: center;
}

.addsub-btn {
    background: linear-gradient(83deg, #24a4fa 20%, #23e1b7 150%) !important;
    color: #fff !important;
    border: none;
    font-weight: 600;
    font-size: 1.12em;
    margin-top: 0.5em;
    padding: 0.57em 1.55em !important;
}

.addsub-btn:not(.selected):hover,
#apps-tab .btn-app:not(.selected):hover,
.nav-platforms .nav-link:not(.active):hover {
    transform: translateY(-2px);
    transition: all 0.2s ease-in-out;
}

#apps-tab .btn-app:not(.selected):hover,
.nav-platforms .nav-link:not(.active):hover {
    filter: brightness(1.2);
}

@media (max-width: 400px) {
    .step-dot {
        width: 29px;
        height: 29px;
    }
}