body {
    background: linear-gradient(135deg, #74ebd5 0%, #9fa4c4 100%);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-radius: 24px !important;
    transition: transform 0.3s ease;
}

.text-gradient {
    background: linear-gradient(45deg, #1e3c72, #2a5298);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.timer-display {
    border: 2px solid rgba(0,0,0,0.05);
    transition: all 0.5s ease;
}

/* Estado ativo: muda de cor igual ao Tkinter antigo */
.timer-active {
    background-color: #e8f5e9 !important;
    border-color: #a5d6a7 !important;
}

.timer-active h2 {
    color: #2e7d32 !important;
}

.timer-paused {
    background-color: #fff3e0 !important;
    border-color: #ffe0b2 !important;
}

.timer-paused h2 {
    color: #ef6c00 !important;
}

.form-control:focus {
    border-color: #2a5298;
    box-shadow: 0 0 0 0.25rem rgba(42, 82, 152, 0.25);
}