body {
    font-family: Arial, sans-serif;
    background: #f3f3f3;
    margin: 0;
    padding: 30px;
}

.page {
    display: flex;
    gap: 25px;
    max-width: 900px;
    margin: auto;
    align-items: flex-start;
}

.signup-card,
.list-card,
.courts-section {
    background: white;
    padding: 30px;
    border-radius: 12px;
    box-sizing: border-box;
}

.signup-card {
    width: 380px;
}

.list-card {
    flex: 1;
}

h1, h2 {
    margin-top: 0;
}

.subtitle {
    font-size: 20px;
}

input {
    width: 100%;
    padding: 14px;
    margin-top: 12px;
    box-sizing: border-box;
    font-size: 18px;
}

button {
    width: 100%;
    padding: 16px;
    margin-top: 15px;
    font-size: 20px;
    cursor: pointer;
    border: none;
    border-radius: 8px;
    background: #2f855a;
    color: white;
}

button.cancel {
    background: #c53030;
}

#status {
    font-size: 18px;
    font-weight: bold;
    margin: 15px 0;
}

#spots-left {
    font-weight: bold;
    font-size: 18px;
}

li {
    font-size: 18px;
    margin-bottom: 8px;
}

.courts-section {
    max-width: 1100px;
    margin: 30px auto 0 auto;
}

.court-note {
    color: #555;
    font-size: 16px;
}

.courts-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 18px;
    margin-top: 20px;
}

.court-card {
    position: relative;
    min-height: 230px;
    border: 4px solid #2f855a;
    border-radius: 14px;
    background: #e6f4ea;
    overflow: hidden;
    padding: 18px;
    box-sizing: border-box;
}

.court-card::before {
    content: "";
    position: absolute;
    inset: 12px;
    border: 2px solid rgba(47, 133, 90, 0.45);
    pointer-events: none;
}

.court-card::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 12px;
    right: 12px;
    border-top: 2px solid rgba(47, 133, 90, 0.45);
    pointer-events: none;
}

.court-number {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 120px;
    font-weight: bold;
    color: rgba(47, 133, 90, 0.16);
    z-index: 0;
}

.court-content {
    position: relative;
    z-index: 1;
}

.court-title {
    font-size: 24px;
    font-weight: bold;
    margin-bottom: 16px;
}

.pair-box {
    background: rgba(255, 255, 255, 0.82);
    border-radius: 10px;
    padding: 12px;
    margin-bottom: 12px;
}

.pair-title {
    font-weight: bold;
    margin-bottom: 6px;
}

.player-name {
    font-size: 18px;
    margin: 4px 0;
}

.empty-court {
    color: #666;
    font-style: italic;
}

@media (max-width: 900px) {
    .courts-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 700px) {
    body {
        padding: 15px;
    }

    .page {
        flex-direction: column;
    }

    .signup-card,
    .list-card {
        width: 100%;
    }

    .courts-grid {
        grid-template-columns: 1fr;
    }
}