/* =========================================
   Slide 20: 商业合作与服务支持 (v2)
   风格：三段式服务旅程 / 企业级合作链路
   母版：三段式流程 / 能力链路（母版 6）
   ========================================= */

#slide-20 {
    position: absolute;
    overflow: hidden;
    padding: 48px 60px 28px;
    color: var(--color-text-main);
    display: flex;
    flex-direction: column;
    background:
        radial-gradient(circle at 10% 14%, rgba(30, 96, 248, 0.11) 0%, rgba(30, 96, 248, 0) 24%),
        radial-gradient(circle at 88% 16%, rgba(14, 165, 233, 0.09) 0%, rgba(14, 165, 233, 0) 22%),
        radial-gradient(circle at 56% 88%, rgba(16, 185, 129, 0.08) 0%, rgba(16, 185, 129, 0) 24%),
        linear-gradient(180deg, #FFFFFF 0%, #F7FAFF 54%, #EEF5FF 100%);
}

/* ── 背景层 ── */
.slide-20-bg-grid,
.slide-20-bg-glow,
.slide-20-bg-orbit {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.slide-20-bg-grid {
    background-image:
        linear-gradient(rgba(30, 96, 248, 0.032) 1px, transparent 1px),
        linear-gradient(90deg, rgba(30, 96, 248, 0.032) 1px, transparent 1px);
    background-size: 52px 52px;
    mask-image: radial-gradient(circle at center, rgba(0, 0, 0, 0.95) 36%, rgba(0, 0, 0, 0.5) 72%, transparent 100%);
    animation: slide-20-grid-drift 34s linear infinite;
}

.slide-20-bg-glow {
    background:
        radial-gradient(circle at 22% 76%, rgba(59, 130, 246, 0.09) 0%, rgba(59, 130, 246, 0) 22%),
        radial-gradient(circle at 72% 32%, rgba(14, 165, 233, 0.07) 0%, rgba(14, 165, 233, 0) 20%),
        radial-gradient(circle at 50% 48%, rgba(255, 255, 255, 0.6) 0%, rgba(255, 255, 255, 0) 50%);
}

.slide-20-bg-orbit::before,
.slide-20-bg-orbit::after {
    content: '';
    position: absolute;
    border-radius: 50%;
    left: 50%;
    transform: translateX(-50%);
}

.slide-20-bg-orbit::before {
    top: 220px;
    width: 1080px;
    height: 420px;
    border: 1px solid rgba(30, 96, 248, 0.06);
}

.slide-20-bg-orbit::after {
    top: 280px;
    width: 780px;
    height: 280px;
    border: 1px dashed rgba(30, 96, 248, 0.04);
}

/* ── 全局 z-index 分层 ── */
.slide-20-header,
.slide-20-body,
.slide-20-footer {
    position: relative;
    z-index: 2;
}

/* ── Header ── */
.slide-20-header {
    margin-bottom: 30px;
    opacity: 0;
    transform: translateY(-22px);
    transition: opacity 0.72s ease 0.12s, transform 0.72s ease 0.12s;
}

.slide-20-title {
    position: relative;
    display: inline-block;
    margin-bottom: 8px;
    font-size: 44px;
    font-weight: 800;
    color: #0F172A;
    line-height: 1.2;
}

.slide-20-title::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -12px;
    width: 114px;
    height: 6px;
    border-radius: 999px;
    background: linear-gradient(90deg, #1E60F8, #0EA5E9, #10B981);
}

.slide-20-subtitle {
    max-width: 1620px;
    font-size: 19px;
    line-height: 1.54;
    color: #475569;;
}

/* ── Body ── */
.slide-20-body {
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding-bottom: 72px;
}

/* ── Phase cards grid ── */
.slide-20-phases {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 26px;
}

/* ── Individual phase card ── */
.slide-20-phase-card {
    position: relative;
    padding: 52px 44px 48px;
    border-radius: 22px;
    background: rgba(255, 255, 255, 0.98);
    border: 1px solid rgba(30, 96, 248, 0.1);
    box-shadow:
        0 8px 32px rgba(15, 23, 42, 0.07),
        0 2px 8px rgba(15, 23, 42, 0.04);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    min-height: 480px;
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 0.72s ease, transform 0.72s ease,
                box-shadow 0.3s ease, border-color 0.3s ease;
}

/* Colored top accent strip */
.slide-20-phase-card::before {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    height: 4px;
    border-radius: 22px 22px 0 0;
}

.phase-discovery::before {
    background: linear-gradient(90deg, #1E60F8, #0EA5E9);
}

.phase-delivery::before {
    background: linear-gradient(90deg, #1E60F8 20%, #10B981);
}

.phase-operations::before {
    background: linear-gradient(90deg, #0EA5E9, #10B981);
}

/* ── Per-card semantic background illustrations ── */
.phase-discovery {
    background-image: url("<svg width='220' height='220' viewBox='0 0 220 220' xmlns='http://www.w3.org/2000/svg'> <line x1='44' y1='140' x2='110' y2='66' stroke='%231E60F8' stroke-width='1.5' opacity='0.18'/> <line x1='110' y1='66' x2='178' y2='110' stroke='%230EA5E9' stroke-width='1.5' opacity='0.18'/> <line x1='44' y1='140' x2='150' y2='170' stroke='%231E60F8' stroke-width='1' opacity='0.13'/> <line x1='178' y1='110' x2='150' y2='170' stroke='%230EA5E9' stroke-width='1' opacity='0.13'/> <line x1='110' y1='66' x2='150' y2='170' stroke='%231E60F8' stroke-width='0.8' opacity='0.1'/> <circle cx='110' cy='66' r='11' fill='%231E60F8' opacity='0.08'/> <circle cx='110' cy='66' r='5.5' fill='%231E60F8' opacity='0.22'/> <circle cx='44' cy='140' r='9' fill='%231E60F8' opacity='0.08'/> <circle cx='44' cy='140' r='4.5' fill='%231E60F8' opacity='0.2'/> <circle cx='178' cy='110' r='9' fill='%230EA5E9' opacity='0.08'/> <circle cx='178' cy='110' r='4.5' fill='%230EA5E9' opacity='0.2'/> <circle cx='150' cy='170' r='8' fill='%230EA5E9' opacity='0.08'/> <circle cx='150' cy='170' r='4' fill='%230EA5E9' opacity='0.2'/> </svg>");
    background-repeat: no-repeat;
    background-position: right -10px bottom -10px;
    background-size: 220px 220px;
}

.phase-delivery {
    background-image: url("<svg width='220' height='220' viewBox='0 0 220 220' xmlns='http://www.w3.org/2000/svg'> <path d='M 30 100 L 88 100 L 88 148 L 170 148' stroke='%231E60F8' stroke-width='1.5' fill='none' opacity='0.18'/> <path d='M 88 100 L 88 54 L 180 54' stroke='%2310B981' stroke-width='1.5' fill='none' opacity='0.18'/> <path d='M 170 148 L 170 188 L 124 188' stroke='%2310B981' stroke-width='1' fill='none' opacity='0.14'/> <circle cx='88' cy='100' r='5.5' fill='%231E60F8' opacity='0.26'/> <circle cx='88' cy='148' r='4.5' fill='%231E60F8' opacity='0.2'/> <circle cx='170' cy='148' r='6.5' fill='%2310B981' opacity='0.26'/> <circle cx='88' cy='54' r='4.5' fill='%2310B981' opacity='0.2'/> <rect x='180' y='46' width='14' height='14' rx='3' stroke='%2310B981' stroke-width='1.2' fill='%2310B981' fill-opacity='0.08' opacity='0.55'/> <rect x='22' y='92' width='14' height='14' rx='3' stroke='%231E60F8' stroke-width='1.2' fill='%231E60F8' fill-opacity='0.08' opacity='0.55'/> </svg>");
    background-repeat: no-repeat;
    background-position: right -10px bottom -10px;
    background-size: 220px 220px;
}

.phase-operations {
    background-image: url("<svg width='220' height='220' viewBox='0 0 220 220' xmlns='http://www.w3.org/2000/svg'> <path d='M 110 28 L 164 56 L 164 112 Q 164 168 110 192 Q 56 168 56 112 L 56 56 Z' stroke='%230EA5E9' stroke-width='1.5' fill='none' opacity='0.12'/> <path d='M 72 122 Q 91 104 110 122 Q 129 104 148 122' stroke='%2310B981' stroke-width='1.5' fill='none' opacity='0.2' stroke-linecap='round'/> <path d='M 83 136 Q 96 120 110 136 Q 124 120 137 136' stroke='%2310B981' stroke-width='1.5' fill='none' opacity='0.26' stroke-linecap='round'/> <circle cx='110' cy='147' r='4.5' fill='%2310B981' opacity='0.3'/> <circle cx='110' cy='147' r='8' fill='none' stroke='%2310B981' stroke-width='1' opacity='0.16'/> </svg>");
    background-repeat: no-repeat;
    background-position: right -10px bottom -10px;
    background-size: 220px 220px;
}

/* Hover only when already active (avoids transform conflict) */
#slide-20.active .slide-20-phase-card:hover {
    box-shadow:
        0 16px 48px rgba(15, 23, 42, 0.12),
        0 4px 16px rgba(30, 96, 248, 0.08);
    border-color: rgba(30, 96, 248, 0.22);
}

/* ── Card header ── */
.phase-card-top {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 24px;
}

.phase-badge {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    background: rgba(30, 96, 248, 0.08);
    color: #1E60F8;
    font-size: 17px;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.phase-operations .phase-badge {
    background: rgba(16, 185, 129, 0.08);
    color: #059669;
}

.phase-en-label {
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: #94A3B8;
}

/* ── Card content ── */
.slide-20-phase-card h3 {
    font-size: 32px;
    font-weight: 800;
    color: #0F172A;
    line-height: 1.3;
    margin-bottom: 16px;
}

.slide-20-phase-card > p {
    font-size: 20px;
    line-height: 1.72;
    color: #475569;
    margin-bottom: 22px;
}

.slide-20-phase-card ul {
    padding-left: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 14px;
    margin-top: auto;
}

.slide-20-phase-card li {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    font-size: 20px;
    font-weight: 600;
    color: #334155;
    line-height: 1.52;
}

.slide-20-phase-card li::before {
    content: '';
    flex-shrink: 0;
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: #1E60F8;
    margin-top: 8px;
}

.phase-operations li::before {
    background: #059669;
}

/* ── Active state triggers ── */
#slide-20.active .slide-20-header {
    opacity: 1;
    transform: translateY(0);
}

#slide-20.active .phase-discovery {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 0.38s;
}

#slide-20.active .phase-delivery {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 0.52s;
}

#slide-20.active .phase-operations {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 0.66s;
}

/* ── Background grid animation ── */
@keyframes slide-20-grid-drift {
    0% { transform: translate3d(0, 0, 0); }
    100% { transform: translate3d(-52px, -52px, 0); }
}